Signs and symptoms
Lesions of erythrasma are initially pink, but progress quickly to become brown and scaly (as skin starts to shed), which are sharply distinguished. Erythrasmic patches are typically found in moist and intertriginous areas (skin fold areas—e.g. armpit, groin, under breast) and can be well-defined patches or irregular. The most common is interdigital erythrasma, which is of the foot, and may present as a scaling, fissuring, and chronic non-resolving break down of the toe web interspaces. The slightly webbed spaces between toes, or other body region skin folds, make it difficult to distinguish from various Tinea. The patient is commonly otherwise asymptomatic. Cause
Erythrasma is caused by Corynebacterium minutissimum. This bacterium tends to thrive in mostly moist and warm environments. Great contributors are poor hygiene, obesity, hyperhidrosis (excessive sweating), aging, diabetes mellitus, and a poorly functioning immune system. Only some of the causable factors can be modified to reduce risk. Hygiene can be improved, along with avoiding moist and warm environments. Diagnosis
The differential diagnosis for erythrasma includes psoriasis, candidiasis, dermatophytosis, and intertrigo. The diagnosis can be made on the clinical picture alone. However, a simple side-room investigation with a Woods lamp is additionally useful in diagnosing erythrasma. The ultraviolet light of a Woods lamp causes the organism to fluoresce a characteristic coral red color, differentiating it from other skin conditions such as tinea versicolor, which may fluoresce a copper-orange color. Another route to differentiate erythrasma would be through bacterial and mycology related cultures to compare/contrast normal results to these findings. These are both non-invasive routes.
Treatment
Initial treatments for minor erythrasma can begin with keeping the area clean and dry and with antibacterial soaps. The next level is treated with topical fusidic acid and an antibacterial solution such as clindamycin to eradicate the bacteria. For aggressive types of erythrasma, oral antibiotics such as macrolides (erythromycin or azithromycin) can be prescribed. Below is a figure showing the different types and subtypes of therapies. There is no agreement on the best treatment for this disease. There are many limitations on these treatments such as more irritation, possible allergic reactions, and ulcerations. These treatments are suitable for most ages, but for young children it should be monitored very closely. Prognosis
Erythrasma has a good prognosis if it is discovered early and properly treated. In more severe cases, it can be an indicator for another disease such as diabetes mellitus. See also
List of cutaneous conditions
Athletes foot
Tinea pedis
Woods lamp
Type 2 diabetes mellitus

References
Further reading
eMedicine
Hamann K, Thorn P (1991). "Systemic or local treatment of erythrasma? A comparison between erythromycin tablets and Fucidin cream in general practice". Scand J Prim Health Care. 9 (1): 35–9. doi:10.3109/02813439109026579. PMID 2041927. == External links ==