Histiocytoses.

Histiocytoses are a heterogeneous group of disorders that are not clearly understood. The unifying aspect of the entire spectrum lies in the accumulation of histiocytes in various tissues. Two cases are being presented for their rarity and the importance of histological features and marker studies in the diagnosis is emphasized.

Pigmentary demarcation lines over the face.

BACKGROUND: We have been observing that a significant proportion of our patients, especially females, have certain pigmentary demarcation lines (PDL) over the face. However, systematic studies of the subject are lacking. AIMS: We categorized the different clinical patterns of facial PDLs in the Indian subpopulation and assessed their prevalence in this study. METHODS: About 4000 consecutive patients, both males and females, attending our skin clinic were examined for the presence of any pigmentary demarcation lines on the face, from October 1998 to February 2000. RESULTS: Out of the study population of 4037 patients, 243 (6%) were found to have demarcation lines on the face. The demarcation lines were far more common in women (9%) than in men (0.75%). These lines could be classified into three patterns that we would like to label as F, G, H as PDLs A to E have already been described. CONCLUSIONS: Pigmentary demarcation lines are fairly common in the Indian population especially amongst the females. Hormonal influences could possibly explain the female preponderance. Aggregation of cases within families or among close relatives suggests a genetic background.

Congenital multiple cutaneous mastocytoma.

A rare case of multiple cutaneous mastocytoma presenting at birth with multiple skin coloured to hyperpigmented papulonodules and plaques all over the body is being reported.

Primary cutaneous phaeohyphomycosis.

A rare case of phaeohyphomycosis presenting with a solitary nodule on right lower leg of 2 years duration is being reported. The disease showed marked response to oral fluconazole.

Nylon friction dermatitis: A distinct subset of macular amyloidosis.

43 patients were taken up for the study, all of whom were asymptomatic and presented with bluish black pigmentation. 23 patients presented with pigmentation which was proximal and distal to the bony prominences, all of whom gave a history of using nylon scrubbers during bathing. 20 patients gave no history of friction and the pigmentation was present on the extensor forearms, shins and upper back. Histopathological examination confirmed amyloid deposits.