Treatment of chronic otitis externa with Trichophyton, Oidiomycetes, Epidermophyton antigen.
Chronic otitis externa may be a sensitivity (dermatophytid) reaction from a distant pathogenic superficial fungal infection, eg, tinea pedis and monilial vaginitis, which are often difficult to eradicate. Skin testing is done with a combined antigenic extract of TOE (Trichophyton; Oidiomycetes, ie, Monilia or Candida albicans; and Epidermophyton). The serial dilution titration method of skin testing is done, and the end point of reaction is determined. Treatment is begun on a weekly basis, with subcutaneous administration of 0.3 cc of a TOE extract two dilutions weaker than the end point. Symptomatic improvement is usually noted within two to four weeks, with objective improvement within eight weeks. After a variable maintenance period, the injections are spaced at less frequent intervals.