Cutaneous cryptococcosis--a case with C3 deposition on capsules

Diagnosis and treatment of infectious diseases in HIV-infected hosts

Treatment of infectious diseases in patients with HIV infection is of primary importance in patient care. Viral, bacterial, parasitic, and fungal pathogens all may affect these patients. It is essential that accurate diagnoses be made and appropriate therapy be administered as early as possible.

Activation of the complement system by pathogenic fungi

Fungi have been studied as prototype activators of the complement cascade since the early 1900s. More recently, attention has focused on the role of the complement system in the pathogenesis of fungal infections. The interactions of Cryptococcus neoformans and Candida albicans with the complement system are the most widely characterized; however, all pathogenic fungi examined to date have the ability to initiate the complement cascade. The molecular mechanisms for initiation and regulation of the complement cascade differ from one fungus to another, most likely reflecting differences in the structure of the outer layers of the cell wall. The molecular bases for such differences remain to be identified. Studies of mycoses in experimental animals with induced or congenital deficiencies in the complement system demonstrate that complement is an important innate system for control of fungal infection. Contributions to host resistance include opsonization and generation of inflammatory mediators. Inflammation induced by chemotactic products of the complement system may contribute to the pathogenesis of some fungal infections.

Localized cutaneous cryptococcosis successfully treated with ketoconazole

A 27-year-old female recipient of a renal allograft, treated with systemic steroids and azathioprine, developed progressive cutaneous lesions (an ulcer, a nodule, and an abscess). Histopathologic and tissue-culture examination of the skin lesions led to the diagnosis of cutaneous cryptococcosis. A description of the light and electron microscopic features of the cutaneous lesions is reported. A thorough visceral investigation failed to detect systemic involvement. The patient was treated with oral ketoconazole (400 mg daily) for 6 months. A gradual healing of the lesions was obtained, and cultures performed 3 months after the onset of treatment failed to show Cryptococcus neoformans. No relapse or dissemination has so far been observed.