CHAPTER XXXII
TINEA CRURIS
General Considerations
Under the name “dhobie itch” this fungus affection is probably better known to Europeans than any other tropical skin disease. This name dhobie or washerman’s itch has been given on account of associating it with the infection of the underclothing while being washed in the pools or streams along with the garments of those who have this skin disease. This, like every other widespread view, has probably some foundation but cannot be verified. It is the eczema marginatum of Hebra.
This affection is caused by various species of Epidermophyton. This genus differs from Trichophyton in that it never invades the hair or hair follicles.
The species which have been more frequently reported are Epidermophyton cruris, E. perneti and E. rubrum. The mycelium is about 4 microns broad and the spores about 5 or 6 microns. All of these fungi can be cultured on Sabouraud’s maltose agar, growth appearing in about a week, except E. perneti, which grows more rapidly.
Symptomatology
The favorite site is the crotch although the axillary region is also frequently involved. The process starts as a papule but these rapidly develop and give rise to an angry red, swollen patch with sharply delimited margins. These red, festooned patches are usually limited to the perineum, scrotum and inner surfaces of the thighs.
The itching is unbearable and many secondary infections or eczematous lesions result from the fierce scratching of the parts.
If the patient goes to a cooler place the process subsides to return when he comes back to the hot moist climate where the infection was originally contracted.