[Histopathological study of XXXX infection].

@entity1 @entity738 @entity39 @entity14931 @entity1373 @entity272 @entity15539
INTRODUCTION: @entity272 by @entity15539 induces the classic @entity738 of aquariums and swimming pools. The histopathological signs have been described primarily in small series of typical cases, generally with no bacteriological evidence. In a national survey of proven infection with @entity15539 detailed data was collected for 63 @entity1 . The aim of this new study was to describe microscopic signs of the infection based upon biopsies taken from these @entity1 . @entity1 AND METHODS: Unstained slides from 32 biopsies of the skin (n=24) or synovial biopsies (n=8) were prepared; they originated from 27 @entity1 . They were examined after standard staining and after Ziehl-Neelsen staining, without knowledge of the clinical data. RESULTS: All biopsies were taken from the upper limb of 18 @entity1 and nine @entity1 of mean age 48 years. Tubercular @entity738 were observed in only 60% of cases. The largest and most numerous were seen in the synovial samples. Due to their palisade appearance, they were occasionally impossible to distinguish from @entity14931 . In 20% of cases, neutrophil collections were seen without @entity738 and in remaining 20% of cases, relatively non-specific infiltrate was observed. Epidermal changes consisted in psoriasiform or @entity1373 , particularly at the edges of ulcerated areas; invasion of the dermo-epidermal junction was seen in five cases. Follicular @entity39 was observed in four cases with lymphoplasmacytic infiltrates remote from the @entity738 being seen in 22 biopsies. Ziehl-Neelsen staining revealed no bacilli. DISCUSSION: The originality of this series consists of bacteriological proof of @entity15539 infection and the absence of biopsy selection based on clinical criteria. It shows that the typical @entity738 are in fact present in less than two third of cases, and that these may be confused with @entity14931 . The chief characteristic of these lesions is the very low concentration of microorganisms present, in contrast with other forms of @entity15539 , making them difficult to see; routine confirmation cannot thus be expected from specific staining procedures. In one case out of five, the infiltrate suggested no infectious origin, although deep skin biopsies and synovial biopsies provided more information. For all forms of @entity39 , whether or not accompanied by collections of neutrophils, a culture should be carried out in a specific medium, even in the absence of microscopic evidence of bacilli.
