Every practitioner of medicine has become aware of the common, chronic and annoying, but usually mild, fungous infections of the skin, hair and nails. In contrast, the less common but frequently fatal types of cutaneous, pulmonary and systemic mycoses were assumed, until recently, to be extremely rare diseases. Such mycoses, although relatively rare when compared with bacterial infections, occur often enough to justify their inclusion in the differential diagnosis of every obscure infectious disease. In the Duke Clinic and Hospital the number of diagnoses of these serious mycotic infections has been compared with the frequency of diagnoses of other diseases in 250,000 consecutive admissions during a fifteen year period. In table 1 it should be noted that although these mycoses are much less common than tuberculosis, bronchiectasis and pulmonary abscess, they are more frequent than such well known diseases as primary polycythemia, hemophilia, acromegaly and hemochromatosis.
The types of mycotic