Donovanosis - a Histological Study

Abstract

Histological study of the biopsy material obtained from ten cases of donovanosis was done. Significant epidermal changes including epidermal hyperplasia and peutrophilic exocytosis were found to be constant features. Pseudoepitheliomatous hyperplasia, spongiosis intracellular oedema and marginal parakeratosis were rather variable features. The predominant cells of the granuloma were plasma cells and histiocytes some of which were laden with Donovan bodies. Presence of neutrophilic microabscess in the superficial areas was another fairly constant finding along with the sprinkling. Newly formed capillaries were always seen though the dense cellular infiltrate. The organisms inside the pathognomonic cells took bright red stain with Giemsa. The capsule was found to be PAS positive. There were plenty of reticulin fibres mostly coarse. Possibly these fibres were related to terminal scarring, so often seen, when lesions heal. Even though the histology appeared to be of diagnostic significance, it may be pointed out that it is easier to find the pathognomonic cells and the organism in tissue spread stained with Giemsa's or Leishman's stain than the fixed tissue sections.