SIR The March-April 1988 issue of the Reviews of Infectious Diseases contained an article by Black et al. [1] reporting a "unique case" of a 12-month-old child with hepatic abscess due to Haemophilus parainfluenzae and a review of the literature for reported cases of H. parainfluenzae infections in children. As noted by the authors, many previous case reports have lacked sufficient information to verify the identification of the organism. Unfortunately, the authors did not include sufficient information to identify their own organism in the case report. Jones et al. [2], in a previous report, noted that 49 of 59 H. parainfluenzae strains submitted to the Centers for Disease Control were actually Haemophilusparaphrophilus. The review by Black et al. did not discuss the frequently misidentified infections due to H. paraphrophilus. We would like to encourage all authors to include sufficient characteristics in their case reports to identify the organism to the species level, even if isolates are confirmed by a reference laboratory. In addition to V-factor requirement and the porphyrin test, nitrate reduction, hemolysis, lysine decarboxylase activity, and acid production from glucose, sucrose, lactose, and xylose should also be determined. Lactose fermentation is one of the few reliable criteria in differentiating H. paraphrophilus from H. parainfluenzae [3]. A 7-year-old girl was recently admitted to University Hospital in Saskatoon with septic artititis of the left hip. The clinical microbiology laboratory initially reported the isolate as H. parainfluenzae, but, when further tests were performed, the organism was correctly identified as H. paraphrophilus. This case and the case reported by Black et al. emphasize the importance of complete identification of all V-factor-only requiring strains of Haemophilus from clinically important infections.