D. L. Cheng

Skin and soft-tissue manifestations of Shewanella putrefaciens infection.

Shewanella putrefaciens, a saprophytic gram-negative rod, is infrequently recovered from clinical specimens. Although a number of clinical syndromes have been attributed to S. putrefaciens, the pathogenic role of this agent remains largely undefined. We report 16 cases of S. putrefaciens infection that occurred at the Veterans General Hospital-Kaohsiung in Taiwan between 1990 and 1995. S. putrefaciens infection was associated with a wide clinical spectrum including bacteremia/septicemia, skin and soft-tissue infection, biliary tract infection, peritonitis, and empyema. Five of our patients had skin and soft-tissue manifestations, including fulminant periorbitofacial cellulitis, dacryocystitis, perineal abscess, finger abscess, and postcholecystectomy wound infection. These clinical features deviated from the chronic ulcers or infected burns of the lower extremities that have been described in previous reports. Seven (44%) of our 16 patients had bacteremia/septicemia, and all seven had underlying hepatobiliary diseases. S. putrefaciens was isolated in mixed cultures of specimens from 14 patients; Escherichia coli was the most common coisolate. Hepatobiliary diseases and malignancy were the major predisposing factors for S. putrefaciens infection of the biliary tract and S. putrefaciens bacteremia/septicemia.

Role of Benzathine Penicillin G in Prophylaxis for Recurrent Streptococcal Cellulitis of the Lower Legs

Cellulitis of the lower leg is an infection caused by streptococci or, less commonly, Staphylococcus aureus and other gram-negative rods. Recurrence of cellulitis is a common problem. In the present study, we evaluated the use of monthly intramuscular injections of benzathine penicillin G to prevent recurrences of cellulitis. A total of 115 patients with definite or presumptive cases of streptococcal cellulitis were enrolled in this study. Eighty-four of these patients who declined follow-up or received incomplete prophylaxis were considered controls. Recurrence occurred in four (12.9%) of 31 cases who received prophylaxis and 16 (19%) of the 84 cases who did not receive prophylaxis. The difference was not statistically significant. Predisposing factors for cellulitis were found in 57 (49.6%) of the 115 enrolled cases and were mostly related to the impairment of local circulation. Administration of prophylaxis successfully reduced the recurrence rate to zero among patients without predisposing factors but failed to prevent recurrence in those with predisposing factors (20%). We conclude that monthly benzathine penicillin G prophylaxis benefits only patients without predisposing factors for cellulitis.