Postgraduate Medicine
ISSN: 0032-5481 (Print) 1941-9260 (Online) Journal homepage: http://www.tandfonline.com/loi/ipgm20
Superficial and cutaneous fungal infections Larry E. Millikan MD To cite this article: Larry E. Millikan MD (1976) Superficial and cutaneous fungal infections, Postgraduate Medicine, 60:1, 52-58, DOI: 10.1080/00325481.1976.11714412 To link to this article: http://dx.doi.org/10.1080/00325481.1976.11714412
Published online: 07 Jul 2016.
Submit your article to this journal
View related articles
Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=ipgm20 Download by: [Flinders University of South Australia]
Date: 08 September 2016, At: 22:34
medical practice today superfitcial and cutaneclus fungal infecticlns diagnosis and treatment Larry E. Millikan, MD School of Medicine University of Missouri-Columbia
Tools for the diagnosis of superficial and Gutaneous fungal infections are readily available and easily used. Ease of diagnosis coupled with recently developed potent, broad-spectrum agents has dramatically improved the outlook for patients with chronic recurring infections.
• The incidence of superficial and cutaneous fungal infection does not seem to have diminished significantly, in spi te of the recent disco very of potent chemotherapeutic agents with broad spectrums of action. This lack of decline is probably related to the vast reservoir of infectious agents in the environment and the perennial susceptibility of the population. Little is known about mechanisms of protection from and immunity to fun gal infections. Rarely, cases of unusual susceptibility to certain organisms have been encountered, and workups of sorne of the se patients have demonstrated defects in host defense that allow one or another species of fungus to proliferate. Further investigations are under way to more carefully delineate the exact role that delayed hypersensitivity plays in fungal infections. Most fungal infections present with characteristic signs and symptoms that allow for ease of diagnosis. Identification of specifie genus and species is usually unnecessary because broad-spectrum agents are now available for therapy. This article discusses general diagnostic methods and therapeutic agents and their application to sorne common types of fungal infections. Confirmatory Diagnostic Tests
Clinical diagnosis of fungal infection can be readily confirmed in the office by the use of elementary laboratory tests. Potassium hydroxide (KOH) in an aqueous 10% to 20% solution can be used to demonstrate the presence of mycelial elements. Infected skin is lightly scraped with a vertically held No. 15 blade and the material is placed on a glass slide. The KOH solution is added, the slide covered with a coverslip, and the preparation allowed to stand until clear. The clearing process can be hastened by gentle heating. The slide is then examined by microscope. Infected hair can be plucked and examined in the same way. Sorne fungal organisms produce fluorescent substances, and a Wood's light (filtered ultraviolet light) can be used to detect fluorescence. The pteridine produced by noninflammatory microsporums fluoresces a bright or yellow green, and use of Wood's light on the scalp permits a rapid diagnosis of the epidemie type of ringworm caused by Microsporum audouinii. Use of the light elsewhere on the body is also helpful. Early
52
POSTGRADUATE MEDICINE • July 1976 • Vol. 60 • No. 1
Pseudomonas superinfection of a chronic candida! paronychia will fluoresce the light green of fluorescein. Erythrasma of the groin is easily confused with fungal infection and can be differentiated by its bright coral red fluorescence when examined un der Wood' s light. Wood' s light accentuates the depigmentation associated with tinea versicolor, and use of the light is helpful in ascertaining the extent of areas to be treated. A recent advance in diagnostic techniques for dermatophytic fungal infection has been the development of a rapidly acting medium called Dermatophyte Test Medium (DTM). This medium changes color markedly when exposed to most dermatophytic fungi and is an extremely useful tool in the busy practitioner' s office. For identification of genus and species, the fungus usually must be cultured on Sabouraud's agar or on a modification of this medium that contains antibiotics. However, as stated previously, such identification is rarely necessary, and a positive DTM culture should be ali that is needed to confirm the diagnosis. Therapeutlc Agents
Therapy for the many fungal infections affecting man has undergone three distinct stages of development. Early attempts at therapy involved the use of complicated agents that acted primarily by causing increased turnover of the skin or by inducing nonspecific inflammation to destroy the fungi. Treatment was primarily the domain of the dermatologist, for the methods used, such as roentgenography (to destroy growing hairs that harbored fungus) and topical application of caustic agents such as benzoic and salicylic acid ointment (Whitfield's ointment), could produce severe reactions. ~
Vol. 60 • No. 1 • July 1976 • POSTGAADUATE MEDICINE
Artist's conception of Treebeard, from J. R. R. Tolkien's Lord of the Rings trilogy.
53
table 1. known spectrum of action of clotrlmazole and rnlconazole nitrate Actinomycosis Aspergillosis Blastomycosis (North and South American) Candidiasis (systemic and mucocutaneous) Chromomycosis Coccidiodomycosis Cryptococcosis Erythrasma Geotrichosis Histoplasmosis Monosporiosis Mycetoma Nocardiosis Phycomycosis Pityrosporosis Sporotrichosis Tine a Trichosporosis
The advent of antibiotic therapy for fungal infections began after World War II with the use of quinolines and the polyene group of antibiotics. The quinolines (including iodochlorhydroxyquin [Vioform]) are still quite useful in day-to-day treatment. Their principal disadvantage is the yellow stain they impart to clothing and treated areas. Agents in the polyene group, such as amphotericin B (Fungizone), affect cell membranes, and although they seem to have a preference for fungal cell walls, they als~damage other cells, especially those of the kidney. Their use is thus limited. Griseofulvin (Fulvicin-U/F, Grifulvin, Grisactin, Gris-PEG), an antibiotic derived from Penicillium patulum, bas a high index of safety but a very low spectrum of activity; it acts strictly on dermatophytes. The final stage of development in the treatment of superficial and cutaneous fungal infection began about five years ago with the disco very of tolnaftate (Tinactin), the first antifungal agent that could be used topieally without causing irritation. This drug is specifie against dermatophytes. Subsequent discovery of clotrimazole (Lotrimin), haloprogin (Halotex), and miconazole nitrate (MieaTin, Monistat) provided agents of increasingly broad spectrum (table 1). Haloprogin is reportedly effective against yeasts, dermatophytes, and sorne contaminant fungi, and miconazole is effective against Gram-
54
positive bacteria and most contaminant fungi, as well as dermatophytes and yeasts. Therapy for fungal infection can be initiated as soon as diagnosis bas been made by means of clinieal signs and symptoms and confirmed with KOH mount examination or DTM culture. As mentioned previously, culture on Sabouraud's agar is useful to identify the exact causative organism, but it is not necessary to wait for these results before initiating prompt and accurate therapy. Specifie diagnosis primarily aids in determining prognosis. Tlnea Capltis
Fungal infection of the scalp used to be extremely common, mainly because man was a reservoir for the anthropophilic fungi that caused ringworm of the scalp. In situations of close physical contact, infection could spread rapidly from person to person, creating epidemies. Much of this reservoir was eradicated when griseofulvin came into use. At the present time, most cases of tinea capitis, including its inflammatory form, kerion, are caused by zoophilie dermatophytes. These organisms are indigenous to animais; when they spread to man they may cause such a severe inflammatory reaction that residual scarring alopecia results. Diagnosis-The epidemie form of tinea capitis is diagnosed by determining the presence of bright green fluorescence in the area of hair loss un der Wood' s light. In unusual cases, infected hair may be plucked and the hair shaft examined for fungal spores. In the more inflammatory, sporadic, zoophilie form of tinea capitis, fluorescence is absent and clinical diagnosis can be confirmed by KOH mount examination or by culture ofplucked hairs. However, confirmation is usually not necessary, for rarely does any other type of organism cause the brisk inflammatory alopecia seen in this type of tinea capitis. Treatment-Griseofulvin is the treatment of choice for tinea capitis at the present time. No topical agent can adequate! y penetrate the hair and clear the infection. Dosage of griseofulvin varies with the type used and the size of the crystals, the new ultramicrocrystal-
POSTGRADUATE MEDICINE • July 1976 • Vol. 60 • No. 1
line preparations allowing the lowest possible dosage. Tinea Corporis, Manuum, Pedis
Diagnosis-Tinea corporis, manuum, and pedis ali involve the glabrous skin and can be easily diagnosed. Tinea corporis is usually caused by zoophilie organisms, such as Microsporum canis; the lesions occur in classic annular (tinea circinata) (figures 1 and 2), arcuate, or other patterns. In sorne cases, however, the use of a home remedy may have obscured the clinical picture and KOH mount examination or a culture may be needed to confirm the clinical impression. Cases of widely disseminated dermatophytic infection are very unusual; differentiai diagnosis of widespread scaly infection should include consideration of scabies, eczema, primary irritant dermatitis, and allergie contact dermatitis. Unusual types of fungal infection can occasionally mimic these, and KOH mount examination or culture on DTM can be used to prove the presence of fun gus. Dermatophytic infection of the feet and bands has a predilection for the intertriginous areas and often involves the nails (figure 3). Fissuring and marked scaling between the toes should prompt a diagnosis of tine a pedis. Treatment- The older therapeutic agents used to treat dermatophytic infections of the glabrous skin, including such irritating peeling agents as Whitfield 's ointment, were effective in the past and are still used (table 2). They do, however, have certain disadvantages that are absent in the new er preparations (table 2). The new topical agents must be applied twice a day for a full three weeks to prevent recurrence of infection.
Figure 1. Tinea corporis (classic ringworm) on trunk of child. Lesion shows moderate clearing in center and activity around periphery.
Figure 2. Tinea corporis caused by Microsporum canis and acquired by playing with pet.
Tlnea Versicolor
Tinea versicolor is caused by the yeast Pityrosporon orbieu/are. Its incidence seems to be increasing, especially among persons of high school and college age. The increase is paradoxical, for only in the last few years has really effective 'therapy for this disorder been available. Diagnosis-The diagnosis of tine a versicolor is easily made by physical examina-
Vol. 60 • No. 1 • July 1976 • POSTGRADUATE MEDICINE
Figure 3. Tinea pedis caused by Trichophyton rubrum. lnvolvement of first and second toes with sparing of third toe is helpful feature in differentiating onychomycosis from psoriasis.
55
table 2. agents used to treat tinea corporis, pedis, manuum, and cruris Ali types of lesions Clotrimazole Haloprogin Miconazole nitrate
Scaly lesions Undecylenate preparations Verdefam cream, solution Whitfield's ointment
Macerated lesions Quinolines Tolnaftate Undecylenate preparations (cream)
table 3. agents us.ed to treat tinea versicolor Acrisorcin Clotrimazole Haloprogin Miconazole nitrate Selenium sulfide Sodium thiosulfate
table 4. agents used to treat candidiasis Topical Amphotericin B Clotrimazole Haloprogin Miconazole nitrate Nystatin Quinolines Thymol
Systemic Amphotericin B Flucytosine
tion. In the winter, the characteristic hyperkeratotic macules on the central trunk and back are fawn-colored; in the summer, the infected are as do not tan and the reverse pattem is seen (figure 4). The diagnosis is confirmed by KOH mount examination of scrapings from pigmented (winter) ordepigmented (summer) areas. Short brittle hyphae and large numbers of· spores, the so-called spaghetti and meatball pattern, will be seen. Culture is not useful in tinea versicolor, for the organism involved is lyophilic and most standard culture media do not support its growth weil. Treatment (table 3 )-The use of selenium
56
sulfide (Exsel, Selsun) or sodium thiosulfate lotion (Komed, Tinver) has always been moderately effective as treatment for tinea versicolor. Both agents, however, are odorous and require repeated and tedious application. The newer agents haloprogin, miconazole, and clotrimazole (table 3) offer an increased cure rate and possibly a decreased rate of recurrence. A full three weeks of twice-daily application to involved areas appears necessary to diminish the recurrence rate, and should be the standard course of therapy for tinea versicolor. Tinea Cruris and Other Lesions of the Groin
Diagnosis-Four different disease entities can cause significant erythema, irritation, and discomfort in the groin. They are tinea cruris, erythrasma, candidiasis, and irritant or allergie contact dermatitis. The initial clinical picture provides perhaps one of the most useful ways to differentiate these conditions. Tinea cruris is characterized by lesions with sharp margins and sorne central clearing, and sparing of the scrotal sac. In contrast, candidiasis is characterized by the presence of many satellite pustules beyond the central involved area and considerable involvement (scaling and erythema) of the scrotal sac. Erythrasma presents as an erythematous plaque without satellite pustules and may or may not involve the scrotal sac. Irritant or allergie contact dermatitis may resemble any of the se infections. The lesions should initially be examined un der Wood' s light. The bacteria causing erythrasma, Corynebacterium minutissimum, characteristically fluoresce a bright coral red. If Wood's light shows no fluorescence, infected material can be examined on KOH mount. Dermatophytes can easily be distinguished from Candida under the microscope and the diagnosis can be confirmed by culture. When results of examination by Wood's light, KOH mount, and culture are ali negative, by exclusion the problem is that of allergie contact or irritant dermatitis. Treatment-Results of screening by Wood's light are especially important for de-
POSTGRADUATE MEDICINE • July 1976 • Vol. 60 • No. 1
termining therapy. Fluorescence indicates the presence of bacterial organisms that will respond to the use of antibacterial soap and erythromycin (Erythrocin, Ilosone). Agents used to treat tinea cruris are shown in table 2. The newer antifungal agents, applied twice a day for two to three weeks, are effective treatment for both candidiasis and tinea cruris. Symptomatic improvement can be seen as early as 24 hours after start of therapy. The infection gradually clears and may be nearly gone within ten days. However, three weeks oftherapy are currently felt necessary to diminish the incidence of recurrence. In contrast to fungal infection, primary irritant or allergie contact dermatitis responds to the use of steroid applied topically.
Figure 4. Tinea versicolor of shoulder. White spots are diagnostic of disease in summer months, when rest of skin tans. ln winter, opposite pattern is seen.
Candidiasis
Diagnosis-Candidiasis flourishes in moist, warm intertriginous areas (figures 5 and 6). In classic form it is easily recognized by its satellite pustules which, when examined on KOH mount, show budding yeast forms and hyphae. Culture is less important in the diagnosis of candidiasis than in that of other infections because saprophytic Candida albicans is commonly found in the human gastrointestinal tract and culture will be positive in up to 60% of the population. To sustain a diagnosis of pathogenic Candida in the gastrointestinal tract, hyphal changes, pseudohyphae, and budding yeast forms must be found. In sorne cases, the clinical characteristics of candidiasis may have been altered by therapy being given for another condition, and careful KOH mount examination is of prime importance to identify the infection. Treatment-Topical treatment (table 4) for extensive candidiasis has been greatly advanced by the development of haloprogin, clotrimazole, and miconazole. These provide alternatives to amphotericin B and nystatin (Mycostatin). Candida! vaginitis can be treated with miconazole (Monistat Cre am), quinolines (Vioform), or nystatin preparations. Topical therapy for the gastrointestinal tract, however, still centers around nystatin in the form of oral tablets or suspension . ..,.
Vol. 60 • No. 1 • July 1976 • POSTGRADUATE MEDICINE
Figure 5. Classic intertriginous candidiasis of submammary area. Note solidity of lesions in and near skin fold and satellite lesions around periphery.
Figure 6. Perlèche caused by candidiasis.
57
Summary
Larry E. Millikan
Dr. Millikan is associate professer, division of dermatology, department of medicine, School of Medicine, University of Missouri-Columbia.
Amphotericin B and flucytosine (Ancobon) are the drugs currently available for systemic therapy of candidiasis (table 4). Miconazole bas been proved effective experimentally and appears to be much Jess toxic than either of these two drugs. No doubt it will become available in the future for systemic treatment of extensive candidiasis. The broad specltrum of different agents shown in table 4 makes possible an aggressive therapeutic approach to generalized candidiasis. Multidrug therapy which is aimed at ali infected areas will eradicate active infection and markedly diminish the rate of recurrence.
58
Fungal infections usually have characteristics that make them easily identifiable. In most cases, clinical diagnosis can be readily confirrned by examining the lesions under Wood' s light or by placing infected mate rial in potassium hydroxide solution and examining the. preparation microscopically. Dermatophytes can be rapidly detected by culturing material on the recently developed Dermatophyte Test Medium. The development of topical antifungal agents with broad spectrums of activity bas considerably simplified treatment. In most cases, culture on Sabouraud's agar to determine exact genus and species before starting therapy is no longer necessary. • Address reprint requests to Larry E. Millikan, MD, Department of Medicine, Division of Dermatology, University of Missouri-Columbia, M752 Medical Center, Columbia, MO 65201.
Reference 1. Taplin D, Zaias N, Rebell G, et al: Isolation and recog-
nition of dermatophytes on a new culture medium (DTM). , Arch Derm 99:203, 1969
POSTGRADUATE MEDICINE • July 1976 • Vol. 60 • No. 1
ISSN: 0032-5481 (Print) 1941-9260 (Online) Journal homepage: http://www.tandfonline.com/loi/ipgm20
Superficial and cutaneous fungal infections Larry E. Millikan MD To cite this article: Larry E. Millikan MD (1976) Superficial and cutaneous fungal infections, Postgraduate Medicine, 60:1, 52-58, DOI: 10.1080/00325481.1976.11714412 To link to this article: http://dx.doi.org/10.1080/00325481.1976.11714412
Published online: 07 Jul 2016.
Submit your article to this journal
View related articles
Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=ipgm20 Download by: [Flinders University of South Australia]
Date: 08 September 2016, At: 22:34
medical practice today superfitcial and cutaneclus fungal infecticlns diagnosis and treatment Larry E. Millikan, MD School of Medicine University of Missouri-Columbia
Tools for the diagnosis of superficial and Gutaneous fungal infections are readily available and easily used. Ease of diagnosis coupled with recently developed potent, broad-spectrum agents has dramatically improved the outlook for patients with chronic recurring infections.
• The incidence of superficial and cutaneous fungal infection does not seem to have diminished significantly, in spi te of the recent disco very of potent chemotherapeutic agents with broad spectrums of action. This lack of decline is probably related to the vast reservoir of infectious agents in the environment and the perennial susceptibility of the population. Little is known about mechanisms of protection from and immunity to fun gal infections. Rarely, cases of unusual susceptibility to certain organisms have been encountered, and workups of sorne of the se patients have demonstrated defects in host defense that allow one or another species of fungus to proliferate. Further investigations are under way to more carefully delineate the exact role that delayed hypersensitivity plays in fungal infections. Most fungal infections present with characteristic signs and symptoms that allow for ease of diagnosis. Identification of specifie genus and species is usually unnecessary because broad-spectrum agents are now available for therapy. This article discusses general diagnostic methods and therapeutic agents and their application to sorne common types of fungal infections. Confirmatory Diagnostic Tests
Clinical diagnosis of fungal infection can be readily confirmed in the office by the use of elementary laboratory tests. Potassium hydroxide (KOH) in an aqueous 10% to 20% solution can be used to demonstrate the presence of mycelial elements. Infected skin is lightly scraped with a vertically held No. 15 blade and the material is placed on a glass slide. The KOH solution is added, the slide covered with a coverslip, and the preparation allowed to stand until clear. The clearing process can be hastened by gentle heating. The slide is then examined by microscope. Infected hair can be plucked and examined in the same way. Sorne fungal organisms produce fluorescent substances, and a Wood's light (filtered ultraviolet light) can be used to detect fluorescence. The pteridine produced by noninflammatory microsporums fluoresces a bright or yellow green, and use of Wood's light on the scalp permits a rapid diagnosis of the epidemie type of ringworm caused by Microsporum audouinii. Use of the light elsewhere on the body is also helpful. Early
52
POSTGRADUATE MEDICINE • July 1976 • Vol. 60 • No. 1
Pseudomonas superinfection of a chronic candida! paronychia will fluoresce the light green of fluorescein. Erythrasma of the groin is easily confused with fungal infection and can be differentiated by its bright coral red fluorescence when examined un der Wood' s light. Wood' s light accentuates the depigmentation associated with tinea versicolor, and use of the light is helpful in ascertaining the extent of areas to be treated. A recent advance in diagnostic techniques for dermatophytic fungal infection has been the development of a rapidly acting medium called Dermatophyte Test Medium (DTM). This medium changes color markedly when exposed to most dermatophytic fungi and is an extremely useful tool in the busy practitioner' s office. For identification of genus and species, the fungus usually must be cultured on Sabouraud's agar or on a modification of this medium that contains antibiotics. However, as stated previously, such identification is rarely necessary, and a positive DTM culture should be ali that is needed to confirm the diagnosis. Therapeutlc Agents
Therapy for the many fungal infections affecting man has undergone three distinct stages of development. Early attempts at therapy involved the use of complicated agents that acted primarily by causing increased turnover of the skin or by inducing nonspecific inflammation to destroy the fungi. Treatment was primarily the domain of the dermatologist, for the methods used, such as roentgenography (to destroy growing hairs that harbored fungus) and topical application of caustic agents such as benzoic and salicylic acid ointment (Whitfield's ointment), could produce severe reactions. ~
Vol. 60 • No. 1 • July 1976 • POSTGAADUATE MEDICINE
Artist's conception of Treebeard, from J. R. R. Tolkien's Lord of the Rings trilogy.
53
table 1. known spectrum of action of clotrlmazole and rnlconazole nitrate Actinomycosis Aspergillosis Blastomycosis (North and South American) Candidiasis (systemic and mucocutaneous) Chromomycosis Coccidiodomycosis Cryptococcosis Erythrasma Geotrichosis Histoplasmosis Monosporiosis Mycetoma Nocardiosis Phycomycosis Pityrosporosis Sporotrichosis Tine a Trichosporosis
The advent of antibiotic therapy for fungal infections began after World War II with the use of quinolines and the polyene group of antibiotics. The quinolines (including iodochlorhydroxyquin [Vioform]) are still quite useful in day-to-day treatment. Their principal disadvantage is the yellow stain they impart to clothing and treated areas. Agents in the polyene group, such as amphotericin B (Fungizone), affect cell membranes, and although they seem to have a preference for fungal cell walls, they als~damage other cells, especially those of the kidney. Their use is thus limited. Griseofulvin (Fulvicin-U/F, Grifulvin, Grisactin, Gris-PEG), an antibiotic derived from Penicillium patulum, bas a high index of safety but a very low spectrum of activity; it acts strictly on dermatophytes. The final stage of development in the treatment of superficial and cutaneous fungal infection began about five years ago with the disco very of tolnaftate (Tinactin), the first antifungal agent that could be used topieally without causing irritation. This drug is specifie against dermatophytes. Subsequent discovery of clotrimazole (Lotrimin), haloprogin (Halotex), and miconazole nitrate (MieaTin, Monistat) provided agents of increasingly broad spectrum (table 1). Haloprogin is reportedly effective against yeasts, dermatophytes, and sorne contaminant fungi, and miconazole is effective against Gram-
54
positive bacteria and most contaminant fungi, as well as dermatophytes and yeasts. Therapy for fungal infection can be initiated as soon as diagnosis bas been made by means of clinieal signs and symptoms and confirmed with KOH mount examination or DTM culture. As mentioned previously, culture on Sabouraud's agar is useful to identify the exact causative organism, but it is not necessary to wait for these results before initiating prompt and accurate therapy. Specifie diagnosis primarily aids in determining prognosis. Tlnea Capltis
Fungal infection of the scalp used to be extremely common, mainly because man was a reservoir for the anthropophilic fungi that caused ringworm of the scalp. In situations of close physical contact, infection could spread rapidly from person to person, creating epidemies. Much of this reservoir was eradicated when griseofulvin came into use. At the present time, most cases of tinea capitis, including its inflammatory form, kerion, are caused by zoophilie dermatophytes. These organisms are indigenous to animais; when they spread to man they may cause such a severe inflammatory reaction that residual scarring alopecia results. Diagnosis-The epidemie form of tinea capitis is diagnosed by determining the presence of bright green fluorescence in the area of hair loss un der Wood' s light. In unusual cases, infected hair may be plucked and the hair shaft examined for fungal spores. In the more inflammatory, sporadic, zoophilie form of tinea capitis, fluorescence is absent and clinical diagnosis can be confirmed by KOH mount examination or by culture ofplucked hairs. However, confirmation is usually not necessary, for rarely does any other type of organism cause the brisk inflammatory alopecia seen in this type of tinea capitis. Treatment-Griseofulvin is the treatment of choice for tinea capitis at the present time. No topical agent can adequate! y penetrate the hair and clear the infection. Dosage of griseofulvin varies with the type used and the size of the crystals, the new ultramicrocrystal-
POSTGRADUATE MEDICINE • July 1976 • Vol. 60 • No. 1
line preparations allowing the lowest possible dosage. Tinea Corporis, Manuum, Pedis
Diagnosis-Tinea corporis, manuum, and pedis ali involve the glabrous skin and can be easily diagnosed. Tinea corporis is usually caused by zoophilie organisms, such as Microsporum canis; the lesions occur in classic annular (tinea circinata) (figures 1 and 2), arcuate, or other patterns. In sorne cases, however, the use of a home remedy may have obscured the clinical picture and KOH mount examination or a culture may be needed to confirm the clinical impression. Cases of widely disseminated dermatophytic infection are very unusual; differentiai diagnosis of widespread scaly infection should include consideration of scabies, eczema, primary irritant dermatitis, and allergie contact dermatitis. Unusual types of fungal infection can occasionally mimic these, and KOH mount examination or culture on DTM can be used to prove the presence of fun gus. Dermatophytic infection of the feet and bands has a predilection for the intertriginous areas and often involves the nails (figure 3). Fissuring and marked scaling between the toes should prompt a diagnosis of tine a pedis. Treatment- The older therapeutic agents used to treat dermatophytic infections of the glabrous skin, including such irritating peeling agents as Whitfield 's ointment, were effective in the past and are still used (table 2). They do, however, have certain disadvantages that are absent in the new er preparations (table 2). The new topical agents must be applied twice a day for a full three weeks to prevent recurrence of infection.
Figure 1. Tinea corporis (classic ringworm) on trunk of child. Lesion shows moderate clearing in center and activity around periphery.
Figure 2. Tinea corporis caused by Microsporum canis and acquired by playing with pet.
Tlnea Versicolor
Tinea versicolor is caused by the yeast Pityrosporon orbieu/are. Its incidence seems to be increasing, especially among persons of high school and college age. The increase is paradoxical, for only in the last few years has really effective 'therapy for this disorder been available. Diagnosis-The diagnosis of tine a versicolor is easily made by physical examina-
Vol. 60 • No. 1 • July 1976 • POSTGRADUATE MEDICINE
Figure 3. Tinea pedis caused by Trichophyton rubrum. lnvolvement of first and second toes with sparing of third toe is helpful feature in differentiating onychomycosis from psoriasis.
55
table 2. agents used to treat tinea corporis, pedis, manuum, and cruris Ali types of lesions Clotrimazole Haloprogin Miconazole nitrate
Scaly lesions Undecylenate preparations Verdefam cream, solution Whitfield's ointment
Macerated lesions Quinolines Tolnaftate Undecylenate preparations (cream)
table 3. agents us.ed to treat tinea versicolor Acrisorcin Clotrimazole Haloprogin Miconazole nitrate Selenium sulfide Sodium thiosulfate
table 4. agents used to treat candidiasis Topical Amphotericin B Clotrimazole Haloprogin Miconazole nitrate Nystatin Quinolines Thymol
Systemic Amphotericin B Flucytosine
tion. In the winter, the characteristic hyperkeratotic macules on the central trunk and back are fawn-colored; in the summer, the infected are as do not tan and the reverse pattem is seen (figure 4). The diagnosis is confirmed by KOH mount examination of scrapings from pigmented (winter) ordepigmented (summer) areas. Short brittle hyphae and large numbers of· spores, the so-called spaghetti and meatball pattern, will be seen. Culture is not useful in tinea versicolor, for the organism involved is lyophilic and most standard culture media do not support its growth weil. Treatment (table 3 )-The use of selenium
56
sulfide (Exsel, Selsun) or sodium thiosulfate lotion (Komed, Tinver) has always been moderately effective as treatment for tinea versicolor. Both agents, however, are odorous and require repeated and tedious application. The newer agents haloprogin, miconazole, and clotrimazole (table 3) offer an increased cure rate and possibly a decreased rate of recurrence. A full three weeks of twice-daily application to involved areas appears necessary to diminish the recurrence rate, and should be the standard course of therapy for tinea versicolor. Tinea Cruris and Other Lesions of the Groin
Diagnosis-Four different disease entities can cause significant erythema, irritation, and discomfort in the groin. They are tinea cruris, erythrasma, candidiasis, and irritant or allergie contact dermatitis. The initial clinical picture provides perhaps one of the most useful ways to differentiate these conditions. Tinea cruris is characterized by lesions with sharp margins and sorne central clearing, and sparing of the scrotal sac. In contrast, candidiasis is characterized by the presence of many satellite pustules beyond the central involved area and considerable involvement (scaling and erythema) of the scrotal sac. Erythrasma presents as an erythematous plaque without satellite pustules and may or may not involve the scrotal sac. Irritant or allergie contact dermatitis may resemble any of the se infections. The lesions should initially be examined un der Wood' s light. The bacteria causing erythrasma, Corynebacterium minutissimum, characteristically fluoresce a bright coral red. If Wood's light shows no fluorescence, infected material can be examined on KOH mount. Dermatophytes can easily be distinguished from Candida under the microscope and the diagnosis can be confirmed by culture. When results of examination by Wood's light, KOH mount, and culture are ali negative, by exclusion the problem is that of allergie contact or irritant dermatitis. Treatment-Results of screening by Wood's light are especially important for de-
POSTGRADUATE MEDICINE • July 1976 • Vol. 60 • No. 1
termining therapy. Fluorescence indicates the presence of bacterial organisms that will respond to the use of antibacterial soap and erythromycin (Erythrocin, Ilosone). Agents used to treat tinea cruris are shown in table 2. The newer antifungal agents, applied twice a day for two to three weeks, are effective treatment for both candidiasis and tinea cruris. Symptomatic improvement can be seen as early as 24 hours after start of therapy. The infection gradually clears and may be nearly gone within ten days. However, three weeks oftherapy are currently felt necessary to diminish the incidence of recurrence. In contrast to fungal infection, primary irritant or allergie contact dermatitis responds to the use of steroid applied topically.
Figure 4. Tinea versicolor of shoulder. White spots are diagnostic of disease in summer months, when rest of skin tans. ln winter, opposite pattern is seen.
Candidiasis
Diagnosis-Candidiasis flourishes in moist, warm intertriginous areas (figures 5 and 6). In classic form it is easily recognized by its satellite pustules which, when examined on KOH mount, show budding yeast forms and hyphae. Culture is less important in the diagnosis of candidiasis than in that of other infections because saprophytic Candida albicans is commonly found in the human gastrointestinal tract and culture will be positive in up to 60% of the population. To sustain a diagnosis of pathogenic Candida in the gastrointestinal tract, hyphal changes, pseudohyphae, and budding yeast forms must be found. In sorne cases, the clinical characteristics of candidiasis may have been altered by therapy being given for another condition, and careful KOH mount examination is of prime importance to identify the infection. Treatment-Topical treatment (table 4) for extensive candidiasis has been greatly advanced by the development of haloprogin, clotrimazole, and miconazole. These provide alternatives to amphotericin B and nystatin (Mycostatin). Candida! vaginitis can be treated with miconazole (Monistat Cre am), quinolines (Vioform), or nystatin preparations. Topical therapy for the gastrointestinal tract, however, still centers around nystatin in the form of oral tablets or suspension . ..,.
Vol. 60 • No. 1 • July 1976 • POSTGRADUATE MEDICINE
Figure 5. Classic intertriginous candidiasis of submammary area. Note solidity of lesions in and near skin fold and satellite lesions around periphery.
Figure 6. Perlèche caused by candidiasis.
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Summary
Larry E. Millikan
Dr. Millikan is associate professer, division of dermatology, department of medicine, School of Medicine, University of Missouri-Columbia.
Amphotericin B and flucytosine (Ancobon) are the drugs currently available for systemic therapy of candidiasis (table 4). Miconazole bas been proved effective experimentally and appears to be much Jess toxic than either of these two drugs. No doubt it will become available in the future for systemic treatment of extensive candidiasis. The broad specltrum of different agents shown in table 4 makes possible an aggressive therapeutic approach to generalized candidiasis. Multidrug therapy which is aimed at ali infected areas will eradicate active infection and markedly diminish the rate of recurrence.
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Fungal infections usually have characteristics that make them easily identifiable. In most cases, clinical diagnosis can be readily confirrned by examining the lesions under Wood' s light or by placing infected mate rial in potassium hydroxide solution and examining the. preparation microscopically. Dermatophytes can be rapidly detected by culturing material on the recently developed Dermatophyte Test Medium. The development of topical antifungal agents with broad spectrums of activity bas considerably simplified treatment. In most cases, culture on Sabouraud's agar to determine exact genus and species before starting therapy is no longer necessary. • Address reprint requests to Larry E. Millikan, MD, Department of Medicine, Division of Dermatology, University of Missouri-Columbia, M752 Medical Center, Columbia, MO 65201.
Reference 1. Taplin D, Zaias N, Rebell G, et al: Isolation and recog-
nition of dermatophytes on a new culture medium (DTM). , Arch Derm 99:203, 1969
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