CORYNEBACTERIUM-PSEUDODIPHTHERITICUM - A RESPIRATORY-TRACT PATHOGEN IN ADULTS

Corynebacterium pseudodiphtheriticum has been reported to be an uncomm on respiratory pathogen, We describe the clinical and microbiologic fe atures of 17 patients from whose sputum C, pseudodiphtheriticum was is olated. Patients were identified through a review of the reports from the clinical microbiology laboratory at York Hospital, a community tea ching hospital, from October 1990 through April 1993; 17 patients with respiratory infection caused by C, pseudodiphtheriticum were identifi ed, There were 12 cases of bronchitis and five of pneumonia. An underl ying systemic condition, particularly congestive heart failure, chroni c obstructive pulmonary disease, diabetes mellitus, or malignancy, was common. Onset of symptomatology was acute for most patients, but feve r was noticeably absent in almost two-thirds of the cases. Isolates we re uniformly susceptible to the beta-lactam antibiotics, vancomycin, a nd trimethoprim-sulfamethoxazole, but resistance to clindamycin and er ythromycin was common. The isolation of diphtheroids from a properly o btained sputum sample from a patient with respiratory tract infection should not always be dismissed as due to contamination. The isolation, identification, and susceptibility testing of C. pseudodiphtheriticum from respiratory tract specimens may provide information useful for t reatment of patients.