Panton-Valentine Leukocidin–producing Staphylococcus aureus

To the Editor: Panton-Valentine leukocidin (PVL) is a cytotoxin produced by Staphylococcus aureus that causes leukocyte destruction and tissue necrosis (1). Although produced by <5% of S. aureus strains, the toxin is detected in large percentages of isolates that cause necrotic skin lesions and severe necrotizing pneumonia (2). Although commonly associated with community-acquired methicillin-resistant S. aureus (CA-MRSA) (3), several outbreaks due to methicillin-susceptible S. aureus (MSSA) have also been reported (4–6). We describe an outbreak of cutaneous infections caused by PVL-producing MSSA that affected 6 of 11 members of 2 related families. During a period of 6 months, a cluster of S. aureus skin and soft tissue infections occurred in 2 families in Jerusalem, Israel, that were related through the mothers, who are sisters. The event started with the 4-year-old boy of family A, who had 5 episodes of skin infections, including 2 episodes of perianal abscesses that required drainage and hospitalization. Culture of pus grew MSSA that was resistant to erythromycin and clin-damycin. Subsequently, recurrent abscesses and cellulitis developed in the boy's father's legs, and his mother had severe periorbital cellulitis that required hospitalization and surgical drainage. Approximately 1 month later, a 9-year-old boy in family B had severe cellulitis and abscess around his knee that required hospitalization and surgical drainage. Subsequently, infections developed in 2 more children in family B: 1 had a finger pulp-space infection and the other cellulitis of the lower abdomen. All pus cultures grew S. aureus with identical susceptibility patterns. The cases are summarized in the Table. Following these events, the families consulted the infectious diseases clinic at the Hadassah-Hebrew University Medical Center in Jerusalem. Since the clinical isolates were not available, nasal cultures were obtained from all family members. S. aureus was isolated from all the affected members of family A and from the parents and the 2 boys in family B. All 7 isolates were subjected to pulsed-field gel electrophoresis (PFGE) after digestion with SmaI. All except 1 had identical band patterns and the same antimicrobial drug sus-ceptibilities as the clinical isolates. The presence of PVL genes was examined by PCR as previously described (2) and was detected only in the isolates with identical PFGE patterns. The families were advised to apply mupirocin nasal ointment twice a day for 5 days and to bathe with 4% chlorhexidine scrub for 1 week (7). At 7 months of follow-up, no new cases of skin …