EXTENDED STUDY OF SERRATIA IN A DIAGNOSTIC BACTERIOLOGY LABORATORY

The incidence of Serratia in clinical material received in a general hospital diagnostic laboratory was studied. Initially the morphologic features, biochemical characteristics, chromogenesis, and antibiotic susceptibility of 21 isolates were examined. On the basis of these studies certain cultural and biochemical tests were selected for routine identification of Serratia.Serratia isolated from various types of clinical specimens received during a 4-year period (1960–1964) were recorded. Most of the Serratia were nonchromogenic except on a special medium. The cultures were resistant to a number of antibiotic agents, particularly penicillin, polymyxin B, and the tetracyclines. A higher incidence of Serratia in sputum than in throat and nasopharyngeal cultures was observed. There was a noticeable increase in the overall incidence of Serratia isolates over the 4-year period. This may be a reflection of hospital acquired infections.