In Reply.—
Skinner at al have observed a frequent appearance of seborrheic dermatitis in patients with the acquired immunodeficiency syndrome (AIDS). This observation is similar to my experience. I did not include seborrheic dermatitis in patients with AIDS as an example of infection in the immunocompromised host for the following reasons.Seborrheic dermatitis is an inflammatory process in which the yeast Pityrosporon may play an important secondary, aggravating role. The most compelling evidence that Pityrosporon ovale is not the causative agent in the classic definition of infection is the demonstration that the clearing of seborrheic dermatitis with an agent such as selenium sulfide followed by continued suppression of Povale with topical amphotericin B results in prompt relapse.1 The presence of disease in the absence of the organism argues strongly against the conclusion that Povale infection causes seborrheic dermatitis. Furthermore, P ovale is the dominant organism on the