Proposed tests for the routine identification of Rochalimaea species

A study was conducted to establish tests for the routine identification of Rochalimaea species. Strains used were reference strains of Rochalimaea vinsonii and Rochalimaea quintana, and a type strain and six human isolates of Rochalimaea henselae. Rochalimaea species were confirmed to be gram-negative, oxidase-negative, non-motile, urease-negative, indole-negative, catalase-negative, glucose-nonfermenting organisms which failed to grow on MacConkey agar. Further testing of the organisms in a commercial identification system with the addition of hemin (100 micrograms/ml) to the medium revealed biochemical reactivity of the organisms not previously observed. The Voges-Proskauer reaction, tests for hydrolysis of hippurate and esculin, leucine arylamidase activity and the lactose test allowed identification and differentiation of the three species. Rochalimaea henselae was the only species with a positive lactose test and Rochalimaea quintana was the only species with a positive Voges-Proskauer reaction. Further studies are needed to confirm the validity of these tests for identification of Rochalimaea species.