Introduction
Pores and skin and comfortable tissue issues, together with rashes, are among the many most frequent medical issues of returned vacationers. A number of giant opinions of dermatologic circumstances in returned vacationers have proven that insect chunk reactions, superficial bacterial infections (typically superimposed on insect bites), and non-specific “itchy rashes” are persistently among the many most typical pores and skin issues recognized at post-travel medical visits (Desk 10.5.1).
Desk 10.5.1: Most typical causes of pores and skin lesions in returned vacationers
| Analysis | Proportion of All Dermatologic Diagnoses (n = 4,742) |
|---|---|
| Cutaneous larva migrans | 9.8% |
| Insect chunk | 8.2% |
| Pores and skin abscess | 7.7% |
| Superinfected insect chunk | 6.8% |
| Allergic rash | 5.5% |
| Rash, unknown origin | 5.5% |
| Canine chunk | 4.3% |
| Superficial fungal an infection | 4.0% |
| Dengue | 3.4% |
| Leishmaniasis | 3.3% |
| Myiasis | 2.7% |
| Noticed fever group rickettsiosis | 1.5% |
| Scabies | 1.5% |
| Cellulitis | 1.5% |
| Different | 32.5% |
Notes
Supply: Modified from Lederman, E. R., Weld, L. H., Elyazar, I. R., von Sonnenburg, F., Loutan, L., Schwartz, E., Keystone, J. S., & GeoSentinel Surveillance Community (2008). Dermatologic circumstances of the sick returned traveler: an evaluation from the GeoSentinel Surveillance Community. Worldwide Journal of Infectious Ailments, 12(6), 593–602. The info within the desk characterize returning vacationers who introduced to journey clinics that have been a part of the GeoSentinel community. Many vacationers returned from the Caribbean, so cutaneous larva migrans was probably extra prevalent than what might have been seen after journey to different locations.
Healthcare professionals usually use a number of approaches concurrently when analyzing a returned traveler with a brand new onset pores and skin situation (Field 10.5.1). Few vacationers’ dermatoses represent a medical emergency. Any pores and skin situation accompanied by fever, obtunded psychological standing, petechiae/purpura, or different indicators of systemic sickness wants a immediate, if not pressing, and thorough diagnostic analysis. Journey locations, sorts (and length) of publicity, and security precautions (e.g., vaccinations, use of mattress nets, sanitary circumstances, and so on.) are the subsequent echelon of inquiry. Subsequent, the healthcare skilled ought to take into account the morphology of pores and skin lesions famous on bodily examination. Major lesions (i.e., these which might be unaltered by time, scratching, crusting, or medical remedy) are most helpful. The scientific analysis could also be easy or might require laboratory affirmation utilizing cultures, serologies, pores and skin biopsy, or microscopy.
Field 10.5.1
Assessing returned vacationers presenting with pores and skin issues: important parts
Pertinent Previous Medical Historical past
- Systemic ailments and continual circumstances, together with preexisting pores and skin circumstances
- Present drugs (and any change in drugs or adherence whereas touring)
- Allergy symptoms
Historical past of the Current Sickness
- Time of onset of lesions (throughout or after journey)
- Related signs: fever, ache, pruritus, bleeding
- Evolution of pores and skin lesions (what did they appear to be after they first appeared, and does the affected person have images of early lesions?)
Journey Historical past
- Location and length of journey
- Publicity historical past: freshwater, seawater, bugs, animals, crops, occupational and leisure exposures, sexual and different human-contact exposures
- Companion vacationers with related findings
- Vaccination standing
- Adherence to straightforward journey precautions (e.g., secure meals and water precautions, insect chunk precautions)
- Medicines taken throughout journey (might present satisfactory prophylaxis for particular circumstances or might need cutaneous unwanted side effects)
- Ingestion of aquatic crops, undercooked fish, crustaceans, reptiles, or amphibians
Bodily Examination
- Form of pores and skin lesions (e.g., macules, nodules, papules, plaques, ulcers)
- Quantity, sample, and distribution of lesions
- Location of lesions: uncovered versus unexposed pores and skin surfaces
Many dermatologic issues in returned vacationers characterize a flare of an current situation, typically as a result of the same old remedy routine was interrupted whereas away from house. Different pores and skin issues would possibly coincide with journey or seem shortly thereafter however are unrelated to journey itself, equivalent to the looks of actinic keratoses (sun-induced cutaneous precancers) in older vacationers with in depth solar publicity historical past.
Fever and rash
Many diseases fall into the class of fever with a rash. In returned vacationers, fever and rash are most frequently, however not all the time, on account of viral infections. However, bacterial infections, parasitic infections, systemic fungal infections, and a few noninfectious circumstances may also trigger fever and rash. If the rash is characterised by petechiae/purpura or by ample vesicles, pustules, or widespread blisters, the analysis ought to be immediate and thorough.
Systemic viral infections and diseases
The primary 3 circumstances mentioned—dengue, chikungunya, and Zika—are viral ailments transmitted by Aedes spp. mosquitoes and infrequently current as undifferentiated fevers. Rashes, significantly widespread petechial eruptions, present vital diagnostic info. Viral diseases typically happen in small outbreaks, so epidemiologic clues are vital.
Dengue
Dengue is characterised by an abrupt onset of excessive fever, frontal headache (typically accompanied by retro-orbital ache), and myalgia (see Dengue chapter). A widespread however faint macular rash, interrupted by islands of uninvolved pallid pores and skin, might seem 2–4 days after sickness onset. A petechial rash might happen in basic and extreme dengue (Determine 10.5.1).
Determine 10.5.1
Chikungunya
The rash related to chikungunya resembles that of dengue, however hemorrhage, shock, and demise are uncommon (see Chikungunya chapter). A significant distinguishing function of chikungunya is its related arthritis, arthralgia, or tenosynovitis that may persist for months, significantly in older adults.
Zika
The course of Zika is usually subclinical or gentle, characterised by arthralgia, conjunctivitis, fever, lymphadenopathy, and a morbilliform (“maculopapular”) rash (see Zika chapter).
Different hemorrhagic fever viruses
Many viruses which might be naturally current in rodents, bats, or non-human primates have the potential to spill over into human populations. Ebola and Marburg viruses are examples. Such viruses would possibly trigger critical, hemorrhagic, or in any other case lethal ailments. Subsequently, if the virus is definitely transmitted from individual to individual, then clusters, outbreaks, and even an epidemic would possibly ensue.
Healthcare professionals involved {that a} returned traveler might have a potential viral hemorrhagic fever ought to notify public well being authorities and provoke precautions to guard the affected person and others. Options of a viral hemorrhagic fever embrace morbilliform eruptions, bleeding within the pores and skin equivalent to petechiae (pinpoint bleeding) and ecchymoses (bruises), gingival bleeding, epistaxis, and different options equivalent to jaundice.
Morbilliform eruptions
Measles
Measles sometimes presents with a prodrome that features fever, cough, runny nostril (coryza), and crimson watery eyes (bilateral conjunctivitis). Koplik spots (small crimson spots with bluish/white heart on the buccal mucosa) start 2–3 days after signs first seem. Inside one other few days, the standard rash begins, often first on the top and neck, then spreading downward to the trunk and extremities. The measles rash consists of innumerable small pink-to-red macules and barely elevated papules, known as a morbilliform or maculopapular eruption. Measles could be unfold simply (see Measles [Rubeola] chapter).
COVID-19
In the course of the course of acute COVID-19 an infection, many individuals develop cutaneous findings (see COVID-19 chapter). The info are imperfect however appear to indicate that rashes fall into 2 giant teams:
- Morbilliform and urticarial eruptions that resemble widespread non-specific viral exanthems
- Eruptions related to hypercoagulability; these are areas of net-like erythema (livedo reticularis, presumably on account of altered vascular perfusion) or pathologic hypercoagulability (retiform purpura)
Non-specific acute morbilliform eruptions are broadly reported as the commonest pores and skin discovering in COVID-19. Many different varieties of eruptions have been attributed to COVID-19. Understanding of the scientific significance, pathophysiology, and epidemiology continues to evolve.
Youngsters and younger adults might develop a situation generally known as “COVID toes,” characterised by sudden onset of painful, dusky crimson macules and patches, sometimes on the plantar side of the distal phalanges of a number of toes. The scientific and histological look of COVID toes resembles a situation generally known as chilblains (a sort of chilly publicity harm).
Acute HIV an infection
Acute retroviral syndrome is the preliminary presentation of newly acquired HIV an infection (see Intercourse and Journey chapter). It presents as an influenza-like syndrome that features fever, generalized lymphadenopathy, and malaise, typically accompanied by a generalized pores and skin eruption. In acute HIV an infection, related pores and skin lesions current as pink to deeply crimson macules or papules, or as a morbilliform eruption. Urticarial and pustular lesions even have been described. Oral ulcers is likely to be current. The scientific look is just not diagnostic and resembles rashes seen in lots of acute viral syndromes.
Acute, febrile, vesiculopustular eruptions
This part consists of ailments brought on by true poxviruses (household: Orthopoxviridae) and a way more widespread situation, chickenpox or varicella, brought on by the varicella-zoster virus (household: Herpesviridae). These viral infections could cause an acute sickness with fever and vesiculopustules that may unfold simply from individual to individual.
Early displays of a poxvirus an infection and a case of chickenpox might resemble one another, despite the fact that they’re virologically, clinically, and epidemiologically dissimilar. The scientific look of every sort of an infection resembles the opposite, superficially.
Poxvirus ailments
Orthopoxvirus infections current equally with fever, headache, malaise, and attribute deep-seated, agency, well-circumscribed lesions that evolve by means of numerous phases (together with papules, vesicles, and pustules). After 2–4 weeks (longer in immunocompromised individuals), lesions mature into crusts that resolve in most people.
Probably the most vital orthopoxvirus illness is smallpox, brought on by variola virus. The virus and the illness have been eradicated in nature, largely because of the world marketing campaign utilizing smallpox vaccine, created from a associated orthopoxvirus, vaccinia virus. In 2022, one other orthopoxvirus illness, mpox, which was as soon as thought of a geographically focal zoonosis, emerged worldwide. In the course of the world outbreak, mpox virus contaminated principally males who’ve intercourse with males. Most circumstances have been transmitted by means of skin-to-skin contact. Consequently, the lesions on many sufferers with mpox appeared primarily or solely on anogenital surfaces. In sufferers with superior HIV illness or different immunocompromised states, the illness could be significantly virulent and may trigger demise.
A number of different poxviruses trigger gentle illness with comparatively few lesions, typically 1–5. In northern Europe, cowpox is current and tends to trigger illness when individuals have direct contact with an contaminated home cat that acquired the illness from a lately caught, contaminated rodent.
Orf and milker’s nodule are brought on by carefully associated parapoxviruses. Most individuals purchase these zoonoses occupationally, often by dealing with or feeding contaminated sheep, cattle, or goats. Though much less widespread, there have been parapoxvirus infections in people with latest publicity to white-tail deer by means of dealing with of carcasses in the US. A localized lesion on the web site of inoculation (typically by means of a pores and skin break) presents after 3–7 days of publicity and may evolve by means of a number of scientific phases; decision often occurs after roughly 4–6 weeks. Fever, malaise, or lymphadenopathy might happen however are unusual.
Varicella (chickenpox)
Varicella (chickenpox) could be gentle in youngsters and extra extreme in adults or immunocompromised sufferers. It presents with 1–2 days of fever, adopted by a generalized pruritic rash consisting of macules that evolve by means of the papular stage (crimson bumps) to kind vesicles (small, clear, fluid-filled blisters) and pustules (pus-filled blisters) on an erythematous base, which resolve by crusting. Lesions typically happen in crops, and numerous phases of evolution are sometimes current concurrently, so papules, vesicles, pustules, and crusts might all happen on the similar time.
Systemic bacterial infections and diseases
Meningococcemia
Invasive Neisseria meningitidis illness happens worldwide and is commonly related to outbreaks, particularly within the meningitis belt of Sub-Saharan Africa (see Meningococcal Illness chapter). Meningococcemia is commonly characterised by acute onset of fever and a petechial or purpuric rash, generally accompanied by hypotension, psychological standing modifications, or multiorgan failure. Fast analysis and rapid remedy (typically began empirically earlier than laboratory affirmation is obtained) could be lifesaving.
Rickettsioses
Most rickettsial infections have distinctive geographic and epidemiologic options based mostly on the ecological preferences and behavioral habits of reservoir animals, arthropod vectors, and pathogens. Many of those “geographic rickettsioses” induce a noticed fever that characteristically begins with the chunk of an contaminated tick or mite. After a several-day incubation interval, the primary cutaneous discovering is commonly an eschar on the chunk web site. Typically referred to as a tache noire (black stain), these are mildly painful, darkish brown or black, necrotic lesions with a crimson rim. The systemic sickness begins over the subsequent few days, often accompanied by a maculopapular, petechial, or vesicular rash.
African tick-bite fever
Rickettsia africae, the micro organism liable for African tick-bite fever (South African tick typhus), is transmitted by the chunk of a tough tick (Hyalomma spp.; Determine 10.5.2). Vacationers who hike or camp outside or are on safari are significantly in danger for this illness, a frequent reason for fever and rash in southern Africa (see Rickettsial Ailments chapter).
Determine 10.5.2
The illness is characterised by fever and an eschar on the web site of the tick chunk. The eschar, or tache noire, is a mildly painful, darkish brown or black, necrotic lesion with a crimson rim. A number of lesions is likely to be current as a result of uncovered people typically endure a number of tick bites. Inside a number of days, sufferers develop a wonderful petechial or papular rash, related to regional lymphadenopathy close to the chunk.
Rocky mountain noticed fever
Rocky Mountain noticed fever (RMSF) is a tick-borne rickettsial illness that’s extra extreme than different noticed fevers. RMSF happens in North America (U.S. and Mexico) and elements of Central and South America. Due to its potential severity and lethality and the necessity for early remedy, take into account RMSF when evaluating sufferers with fever and rash.
Most sufferers with RMSF develop a rash 3–5 days after sickness onset. The standard rash of RMSF begins as a blanching maculopapular eruption. Cutaneous blood vessels turn out to be infected and leaky, typically leading to necrosis. Crimson blood cells leak from infected blood vessels, resulting in non-blanching petechiae which might be particularly outstanding on the ankles and wrists. It often spreads to palms and soles, then turns into generalized. Sufferers with RMSF are often very sick with excessive fever and extreme complications.
Bacterial infections localized to pores and skin and comfortable tissues
Bacterial pores and skin infections happen most continuously when pores and skin floor has been interrupted, typically by abrasions, bites, or minor scratches, significantly beneath circumstances when it’s tough to take care of good hygiene. Widespread organisms accountable are Staphylococcus aureus and Streptococcus pyogenes. Ensuing infections are collectively referred to as pyodermas (Greek for “pus pores and skin”) and may current as impetigo, folliculitis, ecthyma (ulcers or open sores), furuncles (additionally referred to as abscesses or boils), cellulitis and erysipelas, or lymphangitis.
Impetigo
Impetigo is a typical, extremely contagious, superficial bacterial pores and skin an infection. S. aureus and S. pyogenes are the commonest pathogens. Streptococcal impetigo classically presents in youngsters with golden or “honey-colored” crusts shaped from dried serum. Staphylococcal impetigo typically seems in physique folds, particularly the axillae, and would possibly current as fragile pustules.
In temperate climates, most impetigo is brought on by S. aureus, both alone or blended with S. pyogenes. In lots of tropical areas, nevertheless, streptococcal impetigo stays particularly widespread in youngsters. It typically arises as a secondary pores and skin an infection after the epidermal barrier is disrupted by insect bites, scabies, or scratches. Therapy for impetigo varies based mostly on the severity or extent of the an infection and by the suspected pathogen. Mupirocin, a topical antibiotic, is a wonderful remedy for gentle, localized impetigo brought on by both pathogen. Extra in depth infections might require oral antibiotics, however the routine differs by pathogen.
Folliculitis (hair follicle infections) and furunculosis (boils or abscesses)
Folks whose pores and skin or nasal mucosa is colonized with S. aureus are in danger for recurrent folliculitis or furunculosis. By its very nature, folliculitis happens solely on hair-bearing surfaces. Folks can simply however unintentionally unfold the an infection (autoinoculation) after they shave the hair from numerous physique surfaces.
Furuncles might proceed occurring weeks or months after a traveler’s return. If staphylococcal boils recur continuously, remedy might require a decolonization routine with nasal mupirocin and a pores and skin wash with an antimicrobial pores and skin cleanser. Some decolonization protocols advise related remedy for family members and shut contacts.
Many vacationers who develop boils when overseas mistakenly attribute the tender lesions to spider bites. Nevertheless, exterior a number of endemic areas (primarily the south-central U.S.), necrotizing spider bites are extraordinarily uncommon. The lesions in these circumstances are way more more likely to be abscesses brought on by methicillin-resistant S. aureus and ought to be handled accordingly.
Cellulitis and erysipelas
Cellulitis and erysipelas manifest as crimson, heat, edematous areas which may begin on the web site of a minor harm, at a gap within the pores and skin, or with out an apparent underlying suppurative focus. Erysipelas tends to have a clearly raised line of demarcation on the fringe of the lesion. This is because of involvement of superficial lymphatics and is extra more likely to be related to fever. Cellulitis, erysipelas, and lymphangitis are often brought on by S. pyogenes and different β-hemolytic streptococci or S. aureus (together with methicillin-resistant strains), however gram-negative cardio micro organism can also trigger cellulitis.
Therapy
Use cleaning soap and water for native cleaning of bacterial pores and skin infections. A topical antibiotic, ideally mupirocin, will also be used; bacitracin zinc and polymyxin sulfate (typically together) are options. Topical antibiotic ointments are broadly out there in different international locations and will comprise neomycin (a well-recognized reason for acute allergic contact dermatitis), fusidic acid, or gentamicin.
In low- and middle-income international locations, “triple cream” merchandise could also be out there over-the-counter. These typically comprise ultrapotent corticosteroids that may intervene with the therapeutic of widespread infections and have their very own unwanted side effects. In lots of low- and middle-income international locations, an software of gentian violet or potassium permanganate is the remedy of selection for impetigo.
Minor pores and skin abscesses typically reply to incision and drainage while not having antibiotics. Oral or parenteral antibiotics is likely to be required if the pores and skin an infection is deep, increasing, in depth, painful, or related to systemic signs (e.g., fever). Contemplate antibiotic resistance if the situation doesn’t reply to empiric remedy. Bites and scratches from animals (each home and wild) can result in infections with anaerobic micro organism or uncommon gram-negative organisms. Acceptable remedy would possibly require care from specialists who can acquire bacterial cultures, prescribe targeted antibiotic remedy, and carry out surgical debridement, as wanted (see Zoonotic Exposures: Bites, Scratches, and Different Hazards chapter).
Pores and skin lesion morphology
Linear lesions
Cutaneous larva migrans
Cutaneous larva migrans, a situation wherein the pores and skin is infested with zoonotic hookworms (typically Ancyclostoma spp.), presents as an especially itchy, linear, or serpiginous lesion (Determine 10.5.3). The migrating larvae advance slowly within the pores and skin’s uppermost layers. Cutaneous larva migrans is often self-limiting after 4–6 weeks. Albendazole and ivermectin are each efficient therapies, and topical corticosteroids can be utilized to alleviate extreme pruritus, which is commonly current. Occasionally, extra critical illness may end up from invasion of deeper organs.
Determine 10.5.3
A deeper lesion that resembles urticarial patches and that progresses quickly is likely to be on account of larva currens (“working larvae”), brought on by cutaneous migration of filariform larva of Strongyloides stercoralis. Name or e-mail the CDC for suggestions on analysis and remedy of cutaneous larva migrans or larva currens (404-718-4745; parasites@cdc.gov).
Lymphocutaneous or sporotrichoid unfold of an infection
Lymphocutaneous or sporotrichoid unfold of an infection happens when organisms ascend proximally alongside superficial cutaneous lymphatics, producing raised, cord-like, linear lesions. Alternatively, this situation can current as an ascending chain of discontinuous, typically ulcerated nodules (termed nodular lymphangitis) that come up after major percutaneous inoculation of particular pathogens. Causative pathogens could be bacterial (e.g., Francisella tularensis; Nocardia spp.; atypical Mycobacterium spp. [such as Mycobacterium marinum after exposure to brackish water or rapidly growing Mycobacteria after pedicure footbaths]); parasitic (e.g., Leishmania spp., significantly these liable for inflicting Western Hemisphere leishmaniasis); or fungal (e.g., Coccidioides spp., Sporothrix spp.).
Phytophotodermatitis and different noninfectious exposures
Phytophotodermatitis is a noninfectious situation ensuing from the interplay of pure psoralens, most typical within the juice of limes, and photo voltaic ultraviolet A radiation. This typically happens on tropical holidays after vacationers are exterior, getting ready meals or drinks with domestically bought limes. A number of days later, the concerned surfaces might develop painful streaks of blisters, primarily the equal of an exaggerated sunburn. The world heals slowly, evolving into asymptomatic hyperpigmented traces which will take weeks or months to resolve. Due to the several-day delay between the publicity to lime juice and daylight, individuals hardly ever self-identify the reason for this painful rash.
Lengthy linear lesions brought on by cnidarian envenomation (e.g., stings from the tentacles of jellyfish or Portuguese man o’ battle [Physalia physalis]), typically resemble phytophotodermatitis (see Poisonings, Envenomations, and Poisonous Exposures Throughout Journey chapter). One other widespread however self-evident reason for an itchy, typically blistering eruption is acute contact dermatitis on account of black henna. In locations the place henna is often used, the compound paraphenylenediamine is commonly added to crimson or brown henna to make a longer-lasting pigment, black henna. Vacationers who obtain short-term tattoos utilizing black henna (somewhat than the extra conventional crimson or brown henna) are in danger for extreme, typically blistering, acute allergic contact dermatitis on account of paraphenylenediamine.
Macular lesions
Macules and patches (flat lesions) are widespread, typically non-specific, and continuously on account of treatment reactions or viral exanthems. Purpura are sometimes macular, and any purpura related to fever might point out a life-threatening emergency (e.g., meningococcemia).
Leprosy/Hansen’s illness
Leprosy continuously presents with hypopigmented or erythematous patches which might be hypoesthetic to pinprick and related to peripheral nerve enlargement. Newly recognized leprosy circumstances happen virtually solely in immigrants arriving from low- or middle-income international locations the place the illness is endemic. Analysis is made by pores and skin lesion biopsies. The Nationwide Hansen’s Illness Scientific Middle in Baton Rouge, Louisiana, gives consultations (nhdped@hrsa.gov; 800-642-2477).
Lyme illness
Lyme illness is brought on by the spirochete Borrelia burgdorferi sensu lato. Endemic to temperate latitudes in North America, Asia, and Europe, the bacterium that causes Lyme illness is transmitted by means of the chunk of contaminated onerous ticks, genus Ixodes.
Contaminated vacationers current with ≥1 giant erythematous patches (erythema migrans). If ≥1 lesions are current, the primary lesion seems the place the tick chunk occurred; subsequent lesions are on account of secondary, in all probability hematogenous, unfold of Borrelia, not a number of tick bites. Erythema migrans typically is described as targetoid, however many circumstances lack central clearing or red-and-white bands. Lesions usually are asymptomatic. Pruritus, if current, is often intermittent and really gentle. Lesions which might be severely or persistently pruritic are unlikely to be erythema migrans.
Tinea (dermatophyte infections)
Tinea (ringworm) is brought on by a a number of carefully associated superficial fungi (Microsporum, Trichophyton, and Epidermophyton). Typical lesions seem as increasing, crimson, raised rings, with an space of central clearing. Diagnostic strategies embrace fungal tradition, microscopy (put together pores and skin scraping samples with a ten% answer of potassium hydroxide [KOH]), and polymerase chain response. Therapy often includes software of a topical antifungal (e.g., clotrimazole, ketoconazole, miconazole, terbinafine) for a number of weeks or a course of an oral antifungal (e.g., terbinafine, fluconazole, itraconazole). Nystatin-based topical brokers are ineffective.
When a returned traveler has a recalcitrant fungal an infection, take into account acquiring tradition for species identification. An extended course of high-dose oral antifungals is likely to be wanted to deal with extreme or recurrent infections brought on by rising drug-resistant Trichophyton species, equivalent to Trichophyton indotineae, which were detected in vacationers getting back from South and Southeast Asia.
Topical drugs that mix an antifungal agent with a potent corticosteroid (e.g., betamethasone, clobetasol) can be found in lots of international locations; warning vacationers in opposition to their use. Adversarial occasions related to steroid-containing antifungal preparations embrace longer-lasting infections; extra in depth unfold of the an infection over giant areas of the physique; invasion of the fungal pathogen into the deeper pores and skin layers; uncommon presentation of an infection (making analysis tougher); and extreme redness and burning (Determine 10.5.4).
Determine 10.5.4
Tinea versicolor (additionally referred to as pityriasis versicolor)
Attributable to a number of species of the fungus Malassezia (e.g., Malassezia furfur [previously Pityrosporum ovale], Malassezia globosa), tinea versicolor is characterised by ample, asymptomatic, spherical to oval pores and skin patches. Lesions are sometimes 1–3 cm in diameter, however dozens of lesions can coalesce to kind a “map-like” look on the higher chest and again. Affected pores and skin sometimes has a dry or dusty floor. Lesions could be skin-colored, barely hypopigmented, or barely hyperpigmented (versicolor means “modified colour”), however all of the lesions on anybody particular person have a uniform colour (Determine 10.5.5).
Determine 10.5.5
Tinea versicolor could be recognized in numerous methods. A scientific analysis typically is predicated on the looks of the lesions. Underneath the sunshine of a Wooden ultraviolet lamp, the lesion produces a delicate yellowish-green hue, corroborating the analysis. Microscopic examination utilizing a KOH preparation could be confirmatory. The fungi that trigger tinea versicolor are tough to develop in commonplace tradition media.
Topical azole merchandise (e.g., clotrimazole cream, ketoconazole shampoo used as a physique wash), selenium sulfide shampoo, or topical zinc pyrithione are advisable therapies. Systemic azoles (e.g., fluconazole) can be utilized to deal with extreme, relapsing infections, or these recalcitrant to first-line therapies. In lots of international locations, the commonest remedy is Whitfield ointment (salicylic acid 3% and benzoic acid 6%, blended in a automobile equivalent to petrolatum). Oral griseofulvin, topical nystatin, and each oral and topical terbinafine are ineffective in opposition to Malassezia.
Nodular and subcutaneous lesions
Gnathostomiasis
Gnathostomiasis is a nematode infection that happens primarily in Southeast Asia, alongside the Pacific coast of Ecuador and Peru, in elements of Mexico, and Sub-Saharan Africa. Folks purchase gnathostomiasis by consuming uncooked or undercooked, contaminated freshwater fish, amphibians, or reptiles. Contaminated people expertise transient, migratory, subcutaneous nodules typically described as each itchy and painful. A number of experiences counsel that preliminary signs can happen weeks and even years after publicity. Signs are on account of nematode larvae migrating by means of cutaneous and subcutaneous comfortable tissues. People are unintentional, dead-end hosts for gnathostomes. Tissue (pores and skin) and peripheral eosinophilia is widespread. Dependable serologic assessments will not be broadly out there however might be used for analysis. Name or e-mail CDC for suggestions on analysis and remedy (404-718-4745; parasites@cdc.gov).
Loiasis
Loiasis is brought on by Loa loa, a filarial nematode transmitted by day-biting African deer flies (Chrysops spp.). Amongst vacationers, the illness is seen principally in individuals who have lived or labored in endemic areas for a number of months or longer. Scientific manifestations fluctuate amongst sufferers; many individuals develop edematous subcutaneous nodules, typically painful or pruritic and positioned round giant joints. These nodules are generally known as Calabar swellings, named for the Nigeria-Cameroon coastal space the place the illness is prevalent. Some individuals with loiasis have generalized itchy pores and skin with no different cutaneous findings. Grownup worms are often noticed crossing the bulbar conjunctivae or the comfortable eyelid tissues, main to a different identify for loiasis, African eyeworm illness. Peripheral eosinophilia is widespread in vacationers.
Loiasis is recognized utilizing standard mild microscopy to seek out microfilariae (larvae of the worm) on a blood smear. The blood ought to be collected throughout noon hours (i.e., between 10 a.m. and a pair of p.m.). In vacationers who’ve crossed time zones, blood ought to be collected throughout noon hours of the placement the place the an infection was acquired. However, microfilaremia is likely to be undetectable; such circumstances require serologic testing, though an infection with different nematodes might produce a false optimistic take a look at end result.
The drug of selection for the remedy of loiasis is diethylcarbamazine (DEC). Most sufferers will obtain treatment, outlined as decision of signs, decision of eosinophilia, and lowering antifilarial antibody titers, with 1 or 2 programs of DEC. Some would require further programs of DEC or a trial of albendazole. DEC is the remedy of selection as a result of there’s strong proof that it kills each the microfilariae and the grownup worms, leading to faster decision of the an infection. The danger of deadly encephalopathy or different extreme adversarial neurologic occasions is said to the microfilarial load. Quantitative blood smears are required earlier than initiating remedy. Prophylactic DEC (300 mg as soon as every week) can be utilized to forestall an infection in long-term vacationers to endemic areas. DEC, which isn’t Meals and Drug Administration (FDA)-approved in the US, could be obtained by means of session with the Parasitic Ailments Department at CDC (parasites@cdc.gov; 404-718-4745). Albendazole might play a job within the remedy of loiasis in circumstances of failed DEC remedy or as a way to attempt to decrease microfilarial hundreds in order that DEC could also be used safely. Ivermectin might play a job in reducing microfilarial hundreds in order that DEC could also be safely utilized in sure circumstances.
Furuncular myiasis
In Sub-Saharan Africa, furuncular myiasis is brought on by a pores and skin infestation with larvae of the tumbu fly, also referred to as the mango or mputsi fly (Cordylobia anthropophaga and associated species; Determine 10.5.6). Within the Western Hemisphere, larvae of the botfly (Dermatobia hominis) trigger similar-appearing furuncular myiasis. The botfly’s vary extends from central Mexico to the northern half of South America. Typical lesions are solitary; there will also be a number of painful nodules that resemble furuncles (boils). Every nodule holds solely a single larva. The middle of a lesion has a small punctum by means of which the larva each breathes and expels waste.
Determine 10.5.6
Extra mature larvae typically exit on their very own, or they are often gently compressed out of nodules. Extracting larvae could be tough and will take a number of strategies. Begin with obstructing the respiration punctum by making use of an occlusive substance or dressing (equivalent to petroleum jelly) for a number of hours. Larvae might emerge from their dermal domicile in the hunt for air to breathe. Elimination might require a small, superficial incision that allows mild extraction of the larvae. The method ought to be carried out fastidiously to keep away from puncturing the larval physique, which might lead to residual elements retained within the pores and skin. As soon as a larva has been extracted, the newly vacant cavity ought to be flushed with sterile water. Further lesions are sometimes hidden within the scalp, significantly within the case of infestation with Dermatobia. The affected person might require remedy for secondary bacterial an infection and applicable prophylaxis for tetanus. Name or e-mail CDC for suggestions on analysis and remedy (404-718-4745; parasites@cdc.gov).
Tungiasis
Tungiasis is a pores and skin infestation brought on by grownup feminine sand fleas (Tunga penetrans) and is endemic to elements of the Caribbean, South America, and Sub-Saharan Africa. Sometimes, 1 or extra gravid feminine fleas burrow into the thick pores and skin on an individual’s sole or across the toes. Most individuals with tungiasis have a number of lesions. Particular person lesions have a strikingly uniform look with a spherical, 5 mm diameter, white, barely elevated floor. Within the heart of the lesion, a minute, continuously black, opening is current, by means of which the embedded flea breathes, eliminates waste, and ultimately extrudes her eggs. Clustered lesions can seem as crusty, soiled, or draining plaques. The lesions, that are itchy and painful, proceed to broaden because the uterus of the sand flea fills with eggs.
Therapy consists of extracting the burrowed fleas, consideration of antibiotics for secondary bacterial an infection, and prophylaxis for tetanus, if required. Extraction carried out in endemic areas utilizing non-sterile procedures has been related to vital issues. Promising rising topical therapies embrace dimeticones (silicone oils) and a neem/coconut oil combination. Name or e-mail CDC for suggestions on analysis and remedy (404-718-4745; parasites@cdc.gov).
Papular lesions
Bites by bugs and different arthropods
Insect bites are in all probability the commonest reason for papular lesions. Biting bugs embrace mattress bugs, fleas, head lice, midges, mosquitoes, and sand flies. Most bites are itchy due to hypersensitivity reactions to proteins and different elements within the insect’s saliva.
Particular person bites often seem as small (4–10 mm diameter), edematous, pink to crimson papules with a delicate “watch-glass” profile. The middle of many bites may have a small, delicate break within the dermis the place the arthropod’s mouth elements entered the floor of the pores and skin. The pink to crimson colour is usually restricted to the elevated a part of the lesion and is surrounded by a subtly pale hypovascular rim.
Lesions are sometimes pruritic, thereby inducing sufferers to scratch their bites. Scratching typically excoriates or erodes the pores and skin’s floor, placing the positioning in danger for secondary bacterial infections, often with Staphylococcus spp. or Streptococcus spp. Many arthropods produce chunk reactions which have attribute shapes, patterns, and distributions. For instance, bites from mattress bugs and fleas typically seem as clusters of discrete crimson papules on unclothed surfaces of the physique (Determine 10.5.7).
Determine 10.5.7a
Determine 10.5.7b
Scabies
Scabies infestation often manifests as a generalized or regional pruritic papular rash with erythema, ample excoriations, and secondarily contaminated pustules. Scabies usually presents in a regionally symmetric method (Determine 10.5.8). For instance, 2 of essentially the most generally concerned websites are the volar wrists and finger net areas; the left and proper sides are often concerned in an almost an identical style. Additionally, boys and males with scabies typically develop nodular lesions on the scrotum and penis. When contemplating scabies in any male older than 2 years, a genital examination could be extraordinarily useful. Scabies burrows are quick, delicate, linear lesions that contain essentially the most superficial a part of the dermis; burrows are pathognomonic however are difficult to detect. See remedy info.
Determine 10.5.8a
Determine 10.5.8b
Different papular lesions
Many different circumstances current as widespread, extraordinarily pruritic eruptions, typically with quite a few wonderful, barely elevated, considerably vague papules. Examples embrace acute allergic contact dermatitis (maybe on account of crops) and photosensitive dermatitis (typically related to photosensitizing drugs, e.g., doxycycline, sulfonamides). Onchocerciasis (particularly onchocercal dermatitis because of the inflammatory response to dying microfilaria within the pores and skin) can happen in expatriates residing in endemic areas in Sub-Saharan Africa. Onchocercal dermatitis manifests as a generalized pruritic, finely papular dermatitis, a uncommon discovering in vacationers that happens years after publicity. Swimmer’s itch (cercarial dermatitis) and hookworm folliculitis are extraordinarily itchy eruptions composed of papules on pores and skin surfaces uncovered to freshwater and fecally-contaminated soils, respectively.
Pores and skin ulcers
Pores and skin ulcers kind when a damaging course of damages or erodes the dermis, the pores and skin’s superficial layer, after which enters the dermis, the pores and skin’s deeper, extra leathery layer. Probably the most frequent causes of acute (length <1 month) cutaneous ulcers are the widespread pyogenic micro organism, Staphylococcus and Streptococcus. An infection with these organisms creates well-demarcated, shallow ulcers with sharp “punched out” borders generally known as bacterial or widespread ecthyma. Therapy for ecthyma is described earlier on this chapter.
Ulcers seen in some circumstances, such because the chancre of major syphilis, are ulcerated after they first seem. Nevertheless, most pores and skin ulcers begin as an elevated lesion, sometimes a papule or vesicle (or maybe a bigger plaque, nodule, or bulla), with an intact floor. Because the epidermal floor breaks down, the lesion evolves into an erosion or an ulcer. That is the case with the subsequent circumstances to be mentioned, anthrax and cutaneous leishmaniasis, together with many different ailments.
Anthrax
Cutaneous anthrax begins as a big, edematous swelling. Inside a number of days, the pores and skin floor develops a shallow ulcer that progresses right into a necrotic black eschar. In all phases, anthrax lesions are surprisingly painless. Most circumstances of travel-associated anthrax are cutaneous (somewhat than inhalational or gastrointestinal) and are acquired by way of publicity to stay ruminants (hoofed mammals that chew their cud, equivalent to cattle, goats, and sheep) or from dealing with unprocessed merchandise created from animal hides or wool.
Any case of human anthrax ought to be reported instantly to public well being authorities. Anthrax spores can be utilized as a bioweapon (in warfare or in bioterrorism). Due to this fact, circumstances of anthrax, that are extraordinarily uncommon within the developed world, will increase concern for a bioterror or biowarfare assault.
Anthrax remedy requires antibiotics to kill the pathogen, Bacillus anthracis, and antitoxins to neutralize the toxins that the pathogen produces. An FDA-approved vaccine is out there to individuals in sure occupations (veterinarians and different animal handlers; floor troopers).
Buruli ulcer (Mycobacterium ulcerans an infection)
Buruli ulcer is uncommon in vacationers. It’s brought on by a toxin produced by Mycobacterium ulcerans, a freshwater bacterium discovered mostly in equatorial Africa (primarily Ghana and Nigeria) and within the Australian state of Victoria. Buruli ulcers sometimes begin as edematous nodules that come up at websites of minor pores and skin harm. The nodules finally break down and kind increasing invasive wounds. Regardless of in depth wounds, Buruli ulcers typically lack indicators of irritation; in different phrases, they’re surprisingly painless and don’t generate a pustular response.
A situation generally known as tropical ulcer has an analogous look, however it’s exceptionally painful. Like Buruli ulcer, it generally seems on the shins. In contrast to Buruli ulcer, tropical ulcer is felt to be brought on by a polymicrobial bacterial an infection, presumably together with some mycobacteria.
Cutaneous leishmaniasis
The primary areas of threat for cutaneous leishmaniasis (CL) are Africa’s northeastern quadrant, Latin America, South Asia, Central Asia, Mediterranean coastal areas, and the Center East (see Leishmaniasis chapter). The chunk of an contaminated sand fly transmits the Leishmania parasite, and CL lesions begin as localized, typical insect chunk reactions which might be papules or nodules. Over a number of weeks, the lesions evolve slowly into shallow ulcers with raised margins. This resembles a broad, shallow, volcanic caldera. The ulcer’s floor is commonly coated by a dried crust or a uncooked, fibrinous coat. Within the absence of secondary bacterial an infection, leishmanial ulcers are usually painless. Lesions might stay as nodules or papules with out ulceration, which is extra generally seen in Outdated World Illness (Determine 10.5.9; Determine 10.5.10).
Determine 10.5.9
Determine 10.5.10
Particular strategies are needed to substantiate a analysis of CL. The best (and office-based) approach is a modified pores and skin scraping with materials positioned on a glass slide and examined by a dermatopathologist. In vacationers, pathogen speciation is commonly needed to find out whether or not the lesion will stay strictly cutaneous and self-healing or if it can require remedy with treatment (i.e., oral, topical, or intravenous) or presumably cryotherapy or warmth remedy. Confer with the CDC webpage or contact CDC for suggestions on analysis and remedy (404-718-4745; parasites@cdc.gov).
Spider bites
An vital consideration when evaluating a affected person who experiences a spider chunk is that the majority alleged spider bites are merely not spider bites (see Poisonings, Envenomations, and Poisonous Exposures Throughout Journey chapter). The sudden look of a heat, tender lesion with a necrotic heart is commonly recognized (by sufferers, relations, and emergency medical employees) as a spider chunk. Nevertheless, few purported spider bites contain a spider noticed to both chunk the affected person or to merely be current. Certainly, a painful necrotic lesion on this context is extra more likely to be a bacterial pores and skin an infection that probably requires antibiotics.
However, necrotizing spider bites can happen and are most frequently brought on by recluse spiders (Loxosceles spp.). In the US, the commonest perpetrator is the brown recluse (or fiddleback) spider (Loxosceles reclusa), discovered within the south-central United States. The Mediterranean recluse spider (Loxosceles rufescens) resembles the brown recluse. It’s native to the Mediterranean basin and the Close to East. This species has turn out to be widespread, resulting in a big, practically worldwide distribution. It hardly ever bites individuals, and its venom has low toxicity, however it has been implicated in true spider bites. In distinction, many research present that exterior a number of endemic areas, most alleged spider bites are, in actual fact, methicillin-resistant S. aureus infections and ought to be handled accordingly.
Unusual causes
A much less widespread reason for pores and skin ulcers is cutaneous diphtheria (Corynebacterium diphtheriae), which creates a shallow ulcer on the pores and skin. Simply as in oropharyngeal diphtheria, the concerned floor sometimes has a grey membranous floor.
Haemophilus ducreyi causes chancroid, a sexually transmitted an infection, however on a number of island teams within the southwestern Pacific, H. ducreyi causes nonvenereal cutaneous ulcers. One other sexually transmitted an infection, syphilis (Treponema pallidum), may also ulcerate the pores and skin.
Trypanosoma brucei rhodesiense, the protozoal pathogen that causes African trypanosomiasis, can produce a chancre on the chunk web site of the transmitting tsetse fly (Glossina spp.).
Miscellaneous pores and skin infections
Chew-associated infections
Wound infections after cat and canine bites are brought on by quite a lot of microorganisms (see Zoonotic Exposures: Bites, Scratches, and Different Hazards chapter). This consists of S. aureus, alpha, beta, and gamma hemolytic streptococci, a number of genera of gram-negative organisms, and a number of other anaerobes. Pasteurella multocida an infection classically happens after cat bites however may also happen after canine bites; lesions brought on by this organism develop shortly and are sometimes painful. Sufferers missing spleens are at specific threat for extreme cellulitis and sepsis on account of Capnocytophaga canimorsus an infection after canine bites. Administration of cat and canine bites consists of consideration of rabies post-exposure prophylaxis (see Rabies chapter), in addition to tetanus immunization and antibiotic remedy. Keep away from major closure of canine bites to the hand or puncture wounds anyplace on the physique.
Monkey chunk administration consists of wound care, tetanus immunization, rabies post-exposure prophylaxis, and consideration of antimicrobial prophylaxis. Bites and scratches from Outdated World macaque monkeys, even people who seem wholesome, have been related to deadly encephalomyelitis on account of B virus an infection in people; valacyclovir is the advisable post-exposure prophylaxis after high-risk macaque publicity.
Water-associated infections
Pores and skin and comfortable tissue infections (SSTI) can happen after publicity to contemporary, brackish, or salt water, significantly if the pores and skin’s floor is compromised. Infections with water-associated organisms can observe from quite a lot of varieties of pores and skin trauma, together with: abrasions or lacerations sustained throughout swimming or wading; bites or stings from marine or aquatic creatures (see Poisonings, Envenomations, and Poisonous Exposures Throughout Journey chapter); and punctures from fishhooks.
Probably the most virulent SSTI related to marine and estuarine exposures are on account of Vibrio vulnificus and associated non-cholera Vibrio spp. For freshwater exposures, Aeromonas hydrophila is essentially the most harmful pathogen. Numerous pores and skin and comfortable tissue manifestations can happen in affiliation with both an infection, together with abscess formation, cellulitis, ecthyma gangrenosum, and necrotizing fasciitis.
Pending identification of a particular organism, deal with acute infections associated to aquatic harm with an antibiotic that gives each gram-positive and gram-negative protection (e.g., fluoroquinolone or third-generation cephalosporin).
Mycobacterium marinum an infection
Mycobacterium marinum is a free-living environmental bacterium discovered worldwide in heat, ideally brackish, water. The standard onset of an infection is when the micro organism enter the pores and skin after a minor abrasion or shallow puncture harm happens in or round open water. Typical areas for M. marinum an infection embrace knees, shins, and the dorsal surfaces of fingers and ft, the place water-associated minor trauma happens mostly.is never painful, heat, or purulent.
Sufferers describe quite a lot of therapeutic patterns after minor water-associated harm—areas that have been injured however not contaminated heal shortly. In distinction, injured areas that have been contaminated with M. marinum will develop the irregularly bordered, increasing, multinodular violaceous plaques attribute of this an infection. Therapy with antimycobacterial brokers for weeks to months is required as a result of lesions don’t resolve spontaneously. Sometimes, the an infection extends proximally alongside superficial lymphatics, a course of generally known as lymphocutaneous or sporotrichoid unfold.
Pseudomonas aeruginosa an infection
So-called scorching tub folliculitis can happen after utilizing inadequately disinfected swimming swimming pools or scorching tubs. Folliculitis (tender or pruritic folliculocentric crimson papules, papulopustules, or nodules) sometimes develops 8–48 hours after publicity to water contaminated with Pseudomonas aeruginosa. Normally, a number of dozen discrete lesions happen on pores and skin surfaces submerged within the infectious water. Most sufferers have malaise; some have a low-grade fever. The situation is self-limited to 2–12 days; antibiotic remedy is never required.
Vibrio vulnificus an infection
Necrotizing Vibrio vulnificus infections could be acquired in 2 methods: (1) when open pores and skin surfaces are uncovered to contaminated brackish or saltwater; and (2) when individuals eat Vibrio-contaminated uncooked or undercooked shellfish, leading to extreme systemic an infection. The sickness is particularly extreme in individuals with underlying liver illness, typically from alcoholism or circumstances equivalent to hemochromatosis. V. vulnificus pores and skin infections often begin as dramatic cellulitis with hemorrhagic bullae, resulting in necrotizing fasciitis and fulminant sepsis. Usually, infections brought on by these organisms could be extra extreme in immunocompromised individuals (see Immunocompromised Vacationers chapter).
Shewanella an infection
Shewanella, a genus of motile gram-negative bacilli present in heat marine waters worldwide, causes SSTIs that clinically and epidemiologically resemble V. vulnificus infections. Sufferers, typically these with continual liver illness, can develop sepsis and a number of organ failure. Small outbreaks of Shewanella infections have been reported amongst individuals who cross the Mediterranean Sea in crowded, unsound boats. Underneath such circumstances, vacationers who’ve had extended publicity of their ft and legs to contaminated seawater are at excessive threat for Shewanella an infection.
