Clinical, pathogenetic, and laboratory features of Capnocytophaga infections.

Granulocytopenia and oral mucosal defects have been reported to be important predisposing factors to recently recognized cases of Capnocytophaga septicemia. The authors call attention to an apparent preponderance of these cases in the pediatric age group and emphasize laboratory features which they have found helpful in the diagnosis of Capnocytophaga infections. Thirteen patients with Capnocytophaga infections were seen during a seven-year period. Seven of these patients had Capnocytophaga bacteremia. Six of seven bacteremic patients were granulocytopenic, six had oral mucosal defects, and three died. Five of the seven bacteremic patients were younger than 20 years of age. This represents a disproportionate distribution of cases in the pediatric age group within the author's institution, because 43% of blood culture specimens submitted to their microbiology laboratory are obtained from pediatric patients. This observation is supported by a review of the reported cases of Capnocytophaga septicemia in which 7 of 12 patients were younger than 20 years of age. Because Capnocytophaga may superficially resemble the more commonly isolated Fusobacterium nucleatum, distinguishing features for laboratory identification are discussed.