8/7/2019 TineaPedis

1/4

The Health Care of Homeless Persons - Part I - Tinea Pedis (Athletes Foot) 151

Tinea Pedis(Athletes Foot)

Claire J. Carlo, MD

Patricia MacWilliams Bowe,

RN, MS

Severe Tinea Pedis

This gentleman

lives on Bostons

streets and came

to McInnis House

with this burning

and painful rash o

both feet. Note the

prominent scaling

the reddened sole

his feet.

Photo by

James OConnell M

Tinea pedis, also called athletes foot, is a fungal infection of the foot that isvery common among homeless populations. Fungi are plant-like organismsthat live as parasites or saprophytes (organisms that rely on dead tissue for

their nutrition).

Fungi can exist in two forms: yeasts, which are unicellular; molds, with branched structures called

hyphae.Fungi that cause supercial infections of the

skin and nails are called dermatophytes. These fungiinfect the keratin of the top layer of the epidermis aswell as the nails and are responsible for tinea pedis.

Dermatophytes grow will in moist, occlusiveenvironments. Conditions such as diabetes andHIV/AIDS interfere with the bodys immune func-tion and increase the risk of acquiring dermatophyteinfections. These infections are very commonamong homeless populations, as will be outlined

later.

Prevalence and DistributionNearly everyone in the population is exposed

to the common fungi that cause tinea pedis. Eachpersons immune system determines whether infec-tion results from such exposure. As adults age, tinycracks develop in the skin of the feet, increasing thesusceptibility to tinea infections. Once acquired, afungal infection can linger inactively for years andlater become active when a person reaches the age of

60-70. More than 70% of the US population willhave tinea pedis at some time in their lives. Onethird of all patients are estimated to have toenailinfections as well. Diabetes is a signicant riskfactor, as diabetics are 50% more likely to have afungal infection than non-diabetics.

Limited data is available on the prevalence inthe homeless population. One study that examinedthe prevalence of skin disorders among homelessmen staying in a 450-bed shelter in Boston in 1992found 38% of the residents had tinea pedis, and15.5% had toenail onychomycosis.

Symptoms and Diagnosis

There are three forms of tinea pedis: interdigital - macerated, scaly, ssured skin

occurs between the toes, especially in theweb space between the 4th and 5th toes;

plantar (moccasin foot) - ne, powderyscale is present on a reddened backgroundof the sole, heel, and sides of the foot;

vesicular (bullous) - an acute inammatoryreaction consisting of vesicles and pustules.

Individuals may be asymptomatic or mayexperience burning, itching, or stinging.

8/7/2019 TineaPedis

2/4

152 The Health Care of Homeless Persons - Part I - Tinea Pedis (Athletes Foot)

Tinea Pedis of the

Soles and Toes.

The webs of the toes

are macerated with

prominent scaling.

Photo by

James OConnell MD

The diagnosis of tinea pedis is usually madeclinically and based upon the examination of theaffected area. Denitive diagnosis may be madeby scraping the skin for a KOH preparation, a skinbiopsy, or culture of the affected skin. The KOHpreparation is less likely to be positive in severe

cases with maceration of the skin. In mild cases thefungus can usually be recovered in a scraping. Insevere cases it is recovered less than half the time.

In the evaluation and diagnosis of tinea pedis,clinicians should keep in mind that superinfectionwith bacteria can occur.

Toenails infected with tinea pedis appear thick-ened, discolored, and dystrophic.

Treatment and ComplicationsTreatment modalities come in several forms.

Topical agents include creams, powders, and sprays.The creams and sprays are more effective thanpowders.

Topical agents are generally effective in mildforms of interdigital tinea pedis. Non-prescrip-tion, over-the-counter (OTC) topical agents workmoderately well. The less expensive OTC creams,such as clotrimazole (LotriminTM, MycelexTM) andmiconazole (MonistatTM, MicatinTM), work as wellas the more expensive OTC cream terbinane(LamisilTM), but they require 4 weeks of treatment

compared to 1-2 weeks of treatment with terbinanecream. In our clinical practices, the rst choice oftreatment is usually an OTC cream. If the tineapedis is extensive, a prescription topical antifungalwould be used. Prescription topical antifungalcreams, such as econazole (SpectazoleTM) andnystatin (MycostatinTM), are fungicidal and achievea cure in a shorter time. In more extensive tineapedis or with failure of topical agents, oral medica-tions available by prescription can be used.

The length of treatment with topical agentsmay be as long as 4 weeks depending on the creamchosen. Duration of therapy with oral agents canbe 1-2 weeks depending on the medication used.In cases of tinea pedis with inammatory signsand symptoms (including erythema, pruritis, andburning), a combination steroid/antifungal creamcan be used. The steroid is not necessary when signsof inammation are lacking.

Onychomycosis requires treatment with oralantifungal medication for an extended period oftime.

Modes of TransmissionWarm moist areas are fungi friendly. Optimal

environments are dark, damp, and warm. Poorhygiene, closed footwear, minor skin or nail injuries,and prolonged moist skin create ideal environmentsfor transmission.

Tinea pedis is contagious and spread throughdirect contact with people or objects such as showers,

shoes, socks, locker rooms, or pool surfaces. Petscan carry the fungus and may also be a source oftransmission.

PreventionKeeping the feet clean and dry is one of the

best methods of prevention. Other methods arewell-ventilated shoes that t properly and are nottight. Alternating shoes daily will allow shoes to drythoroughly in between wearing. Socks should bedry and changed frequently. Wool socks draw mois-

ture away from feet and are highly recommended.Wearing sandals or ip-ops in public showers orpool areas may also help prevent tinea pedis. Theuse of foot powders is controversial but may behelpful for persons susceptible to tinea pedis whohave frequent exposures to areas where the fungusis suspected.

Special Considerations for Homeless PopulationsRegular and thorough skin examinations

with emphasis on the feet should be conducted

8/7/2019 TineaPedis

3/4

The Health Care of Homeless Persons - Part I - Tinea Pedis (Athletes Foot) 153

by clinicians caring for homeless persons. Goodpatient education, with simple instructions as to theimportance of good foot hygiene, can help preventand minimize the progression of tinea pedis. Goodeducation consists of proper hygiene instructions,emphasizing the importance of drying the feet,practicing good nail care, and wearing properlytting shoes with clean dry socks. Patients shouldbe shown the correct use of any necessary topical ororal treatments.

Clinicians should be vigilant to treat otherpredisposing factors to tinea pedis that occurin homeless and other populations, includingperipheral vascular disease, peripheral neuropathy,alcoholism, and the use of vasoconstrictive drugssuch as cocaine.

SummaryTinea pedis is commonly called athletes foot.

A fungus that grows predominantly in warm moistenvironments causes this infection that involves thefeet and toes. Shoes, showers, and pool or lockerroom areas are frequent culprits that foster andspread tinea pedis infections. Nearly everyone isexposed to this fungus, but ones immune systemdetermines whether an individual will developinfection. For example, diabetics are 50% morelikely to have tinea pedis.

Tinea pedis may present between the digitsof the toes (interdigital), on the plantar surface(plantar), or as vesicles (vesicular). Patients maybe asymptomatic or experience burning, stinging,or itching. Bacterial superinfection, includingcellulitis of the lower extremity, is a complication oftinea pedis.

Prevention is the best measure, especiallywearing dry shoes and socks, properly tting shoes,and sandals or ip-ops in the shower areas. Treat-ment may be a cream, spray, or powder. If the case isextensive or involves the nails (onychomycosis), oralagents may be necessary.

Regular foot exams should be a routine aspectof health care for homeless persons. Clean and drysocks, as well as shoes that are dry and t properly,

Tinea Pedis of the

Toes.

An example of the

typical ssured ski

and scaling betwe

the toes in tinea

pedis.

Photo courtesy

of the CDC

Standing in

interminable lines

is a daily routine fo

homeless persons,

often exposed to

the extremes of

temperature and

weather. These meare waiting for the

doors of a local

shelter to open in

late afternoon.

Photo by

Melissa Shook

8/7/2019 TineaPedis

4/4

154 The Health Care of Homeless Persons - Part I - Tinea Pedis (Athletes Foot)

ReferencesCrawford F, Hart R, Bell-Syer S, Torgerson D, Young P, Russel I . Athletes foot and fungally infected toenails. British

Medical Journal2001;322(7281):288-289.

Markova T. What is the most effective treatment for tinea pedis (athletess foot)? Journal of Family Practice

2002;51(1):21.

Stratigos A, Stern R, Gonzales E, et al. Prevalence of skin disease in a cohort of shelter-based homeless men. Journalof the American Academy of Dermatology1999;41(2 Pt 1):197-202.

Weinstein A, Berman B. Topical treatment of common supercial tinea infections. American Family Physician2002;65(10):2095-2102.

Tinea Pedis Medication List

Generic Brand Cost

Oral agents

uconazole Diucan $$$$

griseofulvin Fulvicin, Grifulvin, Grisactin $$

itraconazole Sporanox $$$$$

ketoconazole Nizoral $$$$

nystatin Mycostatin $

terbinane Lamisil $$$$$

Topical agents

clotrimazole Lotrimin, Mycelex $

econazole Spectazole $$

ketoconazole Nizoral $

miconazole Micatin, Monistat $

naftine Naftin $$

nystatin Mycostatin $

terbinane Lamisil $$$

tolnaftate Tinactin $

are all important for the prevention and treatmentof tinea pedis. However, access to socks and shoesis often limited to the majority of homeless personsliving in shelters and on the streets. Clinicians

should screen carefully for other predisposingfactors, such as peripheral vascular disease, periph-eral neuropathy, and diabetes. Education aboutgood foot care benets all involved. E