Wound erysipelas following appendectomy caused by group B beta-hemolytic Streptococcus (Streptococcus agalactiae)

Case description of a patient who developed erysipelas of the surgical wound following appendectomy for acute appendicitis, and literature review of invasive group B streptococcal infections.

A 65-year-old man with perforated appendicitis underwent urgent appendectomy and drainage. Antibiotic prophylaxis with tobramycin (100 mg) and metronidazole (500 mg) was administered. At surgery, a phlegmon was identified with free perforation of the appendix and purulent peritoneal fluid. Appendectomy, irrigation with 0.9% NaCl solution, and drainage with a Silastic closed-suction drain was performed. A literature search in all languages was performed using MEDLINE, using the search terms surgical site infection, wound infection, group B streptococcus, Streptococcus agalactiae, necrotizing fasciitis, and postoperative infection.

Erysipelas of the surgical wound developed on the fourth postoperative day. Intravenous penicillin and amoxicillin/clavulanic acid were administered empirically. Culture of the wound drainage identified Streptococcus agalactiae and a few colonies of Escherichia coli. The broad-spectrum antibiotic was discontinued, and a 10-day course of penicillin was completed.

Erysipelas of the surgical wound is unusual, and infection with group B streptococci is rare compared with infection by group A streptococci. Streptococcus agalactiae is recognized to be increasingly virulent, with an increasing predilection for bacteremic infections in healthy hosts. Although Streptococcus agalactiae remains highly susceptible to antimicrobial agents effective against gram-positive cocci, the changing epidemiology and potentially invasive nature of these infections should have clinicians alert to the possibility of infection caused by group B streptococci.