- Email: [email protected]
TROUBLES UNDERFOOT
81
available for world distribution. Meanwhile, lepromatous
infrequently painful, recurrent, and debilitating; Behcet’s syndrome and orogenital ulceration may gravely depress the quality of life, and the pruritus of nodular prurigo has been described as excruciating and reaction
is
not
intolerable. Patients with these diseases and doctors who attempt to treat them may well plead for further research dangerous but equally effective analogues.
on
less
TROUBLES UNDERFOOT
pedis, commonly known as athlete’s foot or foot ringworm, occurs predominantly in males, the picture ranging from itchy, scaly toe-web lesions (dermatophytosis simplex [DS]) to a painful, exudative condition with fissuring and bad smell (dermatophytosis complex [DC]). At any one time as much as 10% of the population of the developed world TINEA
has tinea pedis, 1,2 and those most at risk are children at schools with endemic infection3 and certain occupational groups such as coalminers,4,5 the common factor being shared washing and bathing facilities.4,6,’ Almost unknown in the barefooted,tinea pedis also relates to the wearing of shoes that constrict the lateral toe clefts in particular. The resulting moist conditions and rise in local carbon dioxide tension9promote growth of fungi which invade and damage the
stratum
Commonly implicated are interdigitalis, and Epidermophyton
corneum.
Trichophyton rubrum,
T
these are recovered from abnormal interspaces in 25-61°70 of patients, but also from about 97o of normal interspaces.’"’" Tinea pedis does not always respond well to agents of proven efficacy against ringworm elsewhere in the body. These conflicting observations raise doubts about the long-held assumption that the disease is purely a mycotic
floccosum:
infection.
fungi usually coexist with small numbers of diphtheroids and gram-positive cocci, whereas in DC largecolony diphtheroids, thought to be Brevibacterium spp, preponderate.12,13 During severe exacerbations Proteus spp and Pseudomonas aeruginosa also appear. 14 When normal volunteers had their toe interspaces occluded with plastic film for 10 days there was a striking increase in brevibacteria. 12 The interspaces were white, moist, and malodorous, but the condition was symptomless, reverting to normal within 2 days of unwrapping. In volunteers with DS, however, plastic occlusion precipitated typical DC with In DS,
A, Wilkinson DS, Ebling FJG In. Textbook of dermatology, 3rd ed Oxford: Blackwell Scientific Publications, 1979 800-03 2. Jones HE, Reinhardt JH, Rinaldi MG A clinical, mycological and immunological survey for dermatophytosis Arch Dermatol 1973, 108: 61-65. 3 English MP, Gibson MD Studies in the epidemiology of tinea pedis. I. Tinea pedis in schoolchildren Br Med J 1959; i 1442-46. 4. Gentles JC, Holmes JG Foot ringworm in coal-miners. Br J Indust Med 1957; 14: 22-29. 5 Hope YM, Clayton YM, Hay RJ, Noble WC, Elder-Smith JG. Foot infection in coal miners a reassessment. Br J Dermatol 1985; 112: 405-13. 6 English MP, Gibson MD Studies in the epidemiology of tinea pedis. II. Dermatophytes on the floors of swimming-baths. Br Med J 1959; i: 1446-48. 7. Gentles JC, Evans EGV Foot infections in swimming baths. Br Med J 1973; iii: 260-62 8 Reid S Skin disease in Port Moresby and Papua New Guinea Aust J Dermatol 1976; 17: 1-6 9 Allen AM, King RD Occlusion, carbon dioxide and fungal skin infections. Lancet 1978, i. 360-62 10 Kligman AM, Leyden JJ In Maibach HI, Aly R, eds Skin microbiology: relevance to infection. New York. Springer, 1981 203-09 11. Marples MJ, Bailey MJ A search for the presence of pathogenic bacteria and fungi in the interdigital spaces of the foot Br J Dermatol 1957; 69: 379-88 12 Leyden JJ, Kligman AM Interdigital athlete’s foot. Arch Dermatol 1978; 114: 1466-72 13 Pitcher DG. Rapid identification of cell wall components as a guide to the classification of aerobic coryneform bacteria from human skin J Med Microbiol 1977; 10: 439-45 14. Amonette RA, Rosenberg EW Infection of toe webs by gram-negative bacteria Arch Dermatol 1973; 107: 71-73 1. Rook
soggy, which
lacerated, smelly, and uncomfortable interspaces in
fungal elements were sparse but brevibacteria abundant. Further information came from studies in which the interspaces of occluded feet were treated daily with 1% tolnaftate (antifungal), 1% neomycin sulphate (antibacterial), or a combination of the two. Tolnaftate was effective only in DS, whereas neomycin was effective only in DC; the best treatment in this condition was a combination of the two. Treatment with hexachlorophane, predominantly active
against gram-positive organisms, produced a notable worsening of DS, associated with proliferation of Pseudomonas species. The seminal event in tinea pedis is invasion and damage of the stratum corneum by dermatophytes, followed by overgrowth of bacteria when aeration of the foot is impaired as a result of excessive activity or hot weather. In this phase fungi are present only in the deeper layers of the stratum corneum-an observation that probably explains differences in the reported prevalence of dermatophytes in this disease. Brevibacteria, or in severe disease Pseudomonas-both resistant to penicillin-like antibiotics produced by fungi’’—multiply and cause further damage by the action of proteolytic enzymes. Brevibacteria produce the characteristic odour by metabolising methionine to methanethioll7 (the gas largely responsible for the aroma of Cheddar cheese 18 ). The prevention of tinea pedis depends broadly on public health measures to control spread, which at best can have limited success. The more precise knowledge we have of the polymicrobial nature of the established disease offers the promise of more rational and effective treatment. RECURRENT STAPHYLOCOCCAL FURUNCULOSIS STAPHYLOCOCCAL furunculosis is especially likely to recur if skin or nasal carriage of the infecting strain of Staphylococcus aureus persists within the family, then carrier sites in both patient and household members must be identified if the pathogen is to be eradicated. The usual reservoir is the nose, where organisms replicate and thence spread over body surfaces. A few individuals have other carrier sites, including the perineum.Certain strains of Staphylococcus aureus, notably those of phage group II, seem exceptionally gifted at spreading, both over the skin and within communities, and are particularly associated with superficial sepsis outside hospital. Although recurrent infection often ceases spontaneously after two years or so, as many as a quarter of patients will experience recurrent skin sepsis (boils) despite good initial response to treatment;2 systemic antibiotics may control acute infection yet fail to eradicate the organism from carrier sites. Topical antibacterial agents are commonly used in attempts to eliminate the reservoir of infection-for example, cream containing chlorhexidine (0-1%) and neomycin sulphate (0-5%) may be applied to the anterior nares four times daily until the organism is eradicated. Other carrier sites should also be treated and the regimens include cleansing with skin antiseptics, use of antibacterial Youssef N, Wyborn CHE, Holt G, Noble WC, Clayton YM. Ecological effects of antibiotic production by dermatophyte fungi. J Hyg (Camb) 1979; 82: 301-07 16. Jackman PJH. Body odor-the role of skin bacteria. Semin Dermatol 1982, 1: 143-48 17 Sharpe ME, Law BA, Phillips BA. Coryneform bacteria producing methanethiol J 15.
Gen Microbiol 1976; 94: 430-35. 18
1. 2
Sharpe ME, Law BA, Phillips BA, Pitcher DG. Methanethiol production by coryneform bacteria. Strains from dairy and human skin sources and Brevibacterium linens J Gen Microbiol 1977; 101: 345-49. Hedstrom SA Recurrent staphylococcal furunculosis Bacteriological findings and epidemiology in 100 cases. ScandJ Infect Dis 1981, 13: 115-19. Hedstrom SA Treatment and prevention of recurrent staphylococcal furunculosis clinical and bacteriological follow-up Scand J Infect Dis 1985; 17: 55-58
available for world distribution. Meanwhile, lepromatous
infrequently painful, recurrent, and debilitating; Behcet’s syndrome and orogenital ulceration may gravely depress the quality of life, and the pruritus of nodular prurigo has been described as excruciating and reaction
is
not
intolerable. Patients with these diseases and doctors who attempt to treat them may well plead for further research dangerous but equally effective analogues.
on
less
TROUBLES UNDERFOOT
pedis, commonly known as athlete’s foot or foot ringworm, occurs predominantly in males, the picture ranging from itchy, scaly toe-web lesions (dermatophytosis simplex [DS]) to a painful, exudative condition with fissuring and bad smell (dermatophytosis complex [DC]). At any one time as much as 10% of the population of the developed world TINEA
has tinea pedis, 1,2 and those most at risk are children at schools with endemic infection3 and certain occupational groups such as coalminers,4,5 the common factor being shared washing and bathing facilities.4,6,’ Almost unknown in the barefooted,tinea pedis also relates to the wearing of shoes that constrict the lateral toe clefts in particular. The resulting moist conditions and rise in local carbon dioxide tension9promote growth of fungi which invade and damage the
stratum
Commonly implicated are interdigitalis, and Epidermophyton
corneum.
Trichophyton rubrum,
T
these are recovered from abnormal interspaces in 25-61°70 of patients, but also from about 97o of normal interspaces.’"’" Tinea pedis does not always respond well to agents of proven efficacy against ringworm elsewhere in the body. These conflicting observations raise doubts about the long-held assumption that the disease is purely a mycotic
floccosum:
infection.
fungi usually coexist with small numbers of diphtheroids and gram-positive cocci, whereas in DC largecolony diphtheroids, thought to be Brevibacterium spp, preponderate.12,13 During severe exacerbations Proteus spp and Pseudomonas aeruginosa also appear. 14 When normal volunteers had their toe interspaces occluded with plastic film for 10 days there was a striking increase in brevibacteria. 12 The interspaces were white, moist, and malodorous, but the condition was symptomless, reverting to normal within 2 days of unwrapping. In volunteers with DS, however, plastic occlusion precipitated typical DC with In DS,
A, Wilkinson DS, Ebling FJG In. Textbook of dermatology, 3rd ed Oxford: Blackwell Scientific Publications, 1979 800-03 2. Jones HE, Reinhardt JH, Rinaldi MG A clinical, mycological and immunological survey for dermatophytosis Arch Dermatol 1973, 108: 61-65. 3 English MP, Gibson MD Studies in the epidemiology of tinea pedis. I. Tinea pedis in schoolchildren Br Med J 1959; i 1442-46. 4. Gentles JC, Holmes JG Foot ringworm in coal-miners. Br J Indust Med 1957; 14: 22-29. 5 Hope YM, Clayton YM, Hay RJ, Noble WC, Elder-Smith JG. Foot infection in coal miners a reassessment. Br J Dermatol 1985; 112: 405-13. 6 English MP, Gibson MD Studies in the epidemiology of tinea pedis. II. Dermatophytes on the floors of swimming-baths. Br Med J 1959; i: 1446-48. 7. Gentles JC, Evans EGV Foot infections in swimming baths. Br Med J 1973; iii: 260-62 8 Reid S Skin disease in Port Moresby and Papua New Guinea Aust J Dermatol 1976; 17: 1-6 9 Allen AM, King RD Occlusion, carbon dioxide and fungal skin infections. Lancet 1978, i. 360-62 10 Kligman AM, Leyden JJ In Maibach HI, Aly R, eds Skin microbiology: relevance to infection. New York. Springer, 1981 203-09 11. Marples MJ, Bailey MJ A search for the presence of pathogenic bacteria and fungi in the interdigital spaces of the foot Br J Dermatol 1957; 69: 379-88 12 Leyden JJ, Kligman AM Interdigital athlete’s foot. Arch Dermatol 1978; 114: 1466-72 13 Pitcher DG. Rapid identification of cell wall components as a guide to the classification of aerobic coryneform bacteria from human skin J Med Microbiol 1977; 10: 439-45 14. Amonette RA, Rosenberg EW Infection of toe webs by gram-negative bacteria Arch Dermatol 1973; 107: 71-73 1. Rook
soggy, which
lacerated, smelly, and uncomfortable interspaces in
fungal elements were sparse but brevibacteria abundant. Further information came from studies in which the interspaces of occluded feet were treated daily with 1% tolnaftate (antifungal), 1% neomycin sulphate (antibacterial), or a combination of the two. Tolnaftate was effective only in DS, whereas neomycin was effective only in DC; the best treatment in this condition was a combination of the two. Treatment with hexachlorophane, predominantly active
against gram-positive organisms, produced a notable worsening of DS, associated with proliferation of Pseudomonas species. The seminal event in tinea pedis is invasion and damage of the stratum corneum by dermatophytes, followed by overgrowth of bacteria when aeration of the foot is impaired as a result of excessive activity or hot weather. In this phase fungi are present only in the deeper layers of the stratum corneum-an observation that probably explains differences in the reported prevalence of dermatophytes in this disease. Brevibacteria, or in severe disease Pseudomonas-both resistant to penicillin-like antibiotics produced by fungi’’—multiply and cause further damage by the action of proteolytic enzymes. Brevibacteria produce the characteristic odour by metabolising methionine to methanethioll7 (the gas largely responsible for the aroma of Cheddar cheese 18 ). The prevention of tinea pedis depends broadly on public health measures to control spread, which at best can have limited success. The more precise knowledge we have of the polymicrobial nature of the established disease offers the promise of more rational and effective treatment. RECURRENT STAPHYLOCOCCAL FURUNCULOSIS STAPHYLOCOCCAL furunculosis is especially likely to recur if skin or nasal carriage of the infecting strain of Staphylococcus aureus persists within the family, then carrier sites in both patient and household members must be identified if the pathogen is to be eradicated. The usual reservoir is the nose, where organisms replicate and thence spread over body surfaces. A few individuals have other carrier sites, including the perineum.Certain strains of Staphylococcus aureus, notably those of phage group II, seem exceptionally gifted at spreading, both over the skin and within communities, and are particularly associated with superficial sepsis outside hospital. Although recurrent infection often ceases spontaneously after two years or so, as many as a quarter of patients will experience recurrent skin sepsis (boils) despite good initial response to treatment;2 systemic antibiotics may control acute infection yet fail to eradicate the organism from carrier sites. Topical antibacterial agents are commonly used in attempts to eliminate the reservoir of infection-for example, cream containing chlorhexidine (0-1%) and neomycin sulphate (0-5%) may be applied to the anterior nares four times daily until the organism is eradicated. Other carrier sites should also be treated and the regimens include cleansing with skin antiseptics, use of antibacterial Youssef N, Wyborn CHE, Holt G, Noble WC, Clayton YM. Ecological effects of antibiotic production by dermatophyte fungi. J Hyg (Camb) 1979; 82: 301-07 16. Jackman PJH. Body odor-the role of skin bacteria. Semin Dermatol 1982, 1: 143-48 17 Sharpe ME, Law BA, Phillips BA. Coryneform bacteria producing methanethiol J 15.
Gen Microbiol 1976; 94: 430-35. 18
1. 2
Sharpe ME, Law BA, Phillips BA, Pitcher DG. Methanethiol production by coryneform bacteria. Strains from dairy and human skin sources and Brevibacterium linens J Gen Microbiol 1977; 101: 345-49. Hedstrom SA Recurrent staphylococcal furunculosis Bacteriological findings and epidemiology in 100 cases. ScandJ Infect Dis 1981, 13: 115-19. Hedstrom SA Treatment and prevention of recurrent staphylococcal furunculosis clinical and bacteriological follow-up Scand J Infect Dis 1985; 17: 55-58