Dermatopathology in sub-Saharan Africa: a systematic 5-year analysis of all histopathological diagnoses from the Regional Dermatology Training Centre (RDTC) in Moshi, Tanzania.

BACKGROUND: Proper diagnosis of skin diseases relies on dermatopathology, the most important diagnostic technique in dermatology. Unfortunately, there are few dermatopathology institutions in sub-Saharan Africa, where little is known about the spectrum of histopathological features observed. OBJECTIVES: To investigate the spectrum of dermatopathological diagnoses made in a sub-Saharan African reference centre of a large, mainly rural area. PATIENTS/METHODS: To retrospectively evaluate all dermatopathological diagnoses made over a period of 5 years at the Regional Dermatology Training Centre (RDTC) in Moshi, Tanzania. RESULTS: There were a total of 1554 skin biopsy specimens. In 45% of cases, there were inflammatory diseases, most frequently lichenoid conditions. Cutaneous neoplasms represented 30.4% of all diagnoses, with Kaposi's sarcoma (KS) and, less frequently, squamous cell carcinoma (SCC) being the two most common neoplastic conditions. The latter also reflected the intensive management of persons with albinism in the RDTC. The distribution of histological diagnoses seemed to correlate with the overall clinical spectrum of cutaneous diseases managed in the RDTC. CONCLUSIONS: In this African study inflammatory conditions are the main burden of skin diseases leading to a diagnostic biopsy. Our findings provide further evidence that KS, primarily related to the high prevalence of HIV infection is an epidemiological problem. Both SCC and basal cell carcinoma represent another relatively common malignant cutaneous neoplasms, reflecting the presence of specific populations at risk. The challenging spectrum of histological diagnoses observed in this specific African setting with basic working conditions shows that development of laboratory services of good standards and specific training in dermatopathology are urgently needed.

Staphylococcus aureus in atopic dermatitis and in nonatopic dermatitis.

Skin colonization with Staphylococcus aureus (S. aureus) was examined in 30 patients with atopic dermatitis (AD), in 25 patients with nonatopic eczema (NAE) and in 30 individuals as healthy controls (HC). Bacteria growth was examined in aerobic cultures and the population densities per dish were estimated; S. aureus colonization was found in the eczematous skin of 24 of 30 (80%) AD patients and in 13 of 25 (52%) NAE patients (NS, p greater than 0.1). In nonaffected skin S. aureus colonization was found in 19 of 30 (63%) of all AD patients compared with 6 of 25 (24%) in NAE patients and 1 of 30 (3%) in HC, respectively (p less than 0.05). In nonaffected skin, coagulase negative strains of staphylococcus were found in 25 of 30 (84%) controls and in 18 of 25 (72%) NAE patients compared with 12 of 30 (40%) patients with AD. It seems that colonization with S. aureus is not a characteristic feature for atopic dermatitis but is a frequent event in damaged skin; significantly elevated values were also observed in nonatopic eczema. The degree of colonization may depend on the severity and duration of the eczematous lesions.