Erythrasma

By Baerensprung 1862.

Baerensprung's disease.

Superficial infection with the gram-positive, aerobic Bacillius corynebacterium minutissimum.

• Prevalence: 4-6% of the total population in Central Europe, higher prevalence in tropical zones
• Older studies from England and New Zealand put the prevalence at around 20%
• Rarely seen in children
• Frequently seen in healthy patients

• Predisposing factors:
  • Male gender
  • Diabetes mellitus
  • Older age
  • Immunosuppression
  • Overweight
  • Hyperhidrosis
  • High humidity
  • Warm environment
  • Poor hygiene

• Pathogen: Corynebacterium minutissimum, which produces porphyrin. Wood's light shows a red fluorescence
• The bacteria penetrate the upper stratum corneum through skin defects

• Up to 10.0 cm in size, sharply circumscribed macules, sometimes confluent, often pruritic reddish-brown, and later plaques with fine lamellar scaling. The itching is favoured by sweating and prolonged sitting. The disease is often associated with bromhidrosis, keratoma sulcatum and trichobacteriosis axillaris
• In the interdigital spaces of the toes, corynebacteria are the most common cause of bacterial infections. Interdigital mycosis may also exist at the same time
• The discoid form is not limited to the intertriginous areas. Discoid erythrasma is more common in women with black skin in tropical latitudes
• When erythrasma occurs in the genital or anal area, the latter often develops chronic pruritus

• Clinic
• Wood light examination: coral red fluorescence (Pat. should not have bathed shortly before, as the porphyrins are water-soluble. The test would be falsely negative in this case.)
• Detection of pathogens using the tear-off method with adhesive tape
• No Gram stain, culture or biopsy necessary
• KOH e.g. of a tinea interdigitalis
• HIV test

Intertrigines (groin, axilla, anal, abdominal crease, submammary, great labia, scrotum, thigh and interdigital space).

• The bacteria can often be detected in the stratum corneum. In addition, a discrete perivascular infiltrate
is seen
• Culture (possible, but not necessary for diagnosis)

1. Somerville DA. Erythrasma in normal young adults. J Med Microbiol 1970;3:57-64.
2. Allen S, Christmas TI, McKinney W, Parr D, Oliver GF. The Auckland skin clinic tinea pedis and erythrasma study. N Z Med J 1990;103:391-3.
3. Blaise G, Nikkels AF, Hermanns-Le T, Nikkels-Tassoudji N, Pierard GE. Corynebacterium-associated skin infections. Int J Dermatol 2008;47:884-90.
4. Holdiness MR. Management of cutaneous erythrasma. Drugs 2002;62:1131-41.
5. Mattox TF, Rutgers J, Yoshimori RN, Bhatia NN. Nonfluorescent erythrasma of the vulva. Obstet Gynecol 1993;81:862-4.
6. Hamann K, Thorn P. Systemic or Local Treatment of Erythrasma? A comparison between Erythromycin Tablets and Fucidin R Cream in General Practice. Scandinavian Journal of Primary Health Care 1991;9:35-9.
7. Macmillan AL, Sarkany I. SPECIFIC TOPICAL THEEAPY FOR ERYTHRASMA. Br J Dermatol 1970;82:507-9.
8. Rho N-K, Kim B-J. A corynebacterial triad: Prevalence of erythrasma and trichomycosis axillaris in soldiers with pitted keratolysis. Journal of the American Academy of Dermatology 2008;58:S57-S8.