[Detection and significance of histidine decarboxylase (HDC) in "Klebsiella", "Enterobacter" and "Serratia" (author's transl)].

A quick colorimetric procedure for detection of histidine decarboxylase (HDC) in cultures of Klebsiella, Enterobacter and Serratia is described. Only E. aerogenes could decarboxylate histidine (production of histamine). The interest of HDC test for differentiation of E. aerogenes from K. pneumoniae (especially urease negative strains) is discussed.