An outbreak of extended-spectrum, beta-lactamase-producing Salmonella senftenberg in a burns ward

A strain of Salmonella senftenberg resistant to ceftazidime, gentamicin, ch loramphenicol and ciprofloxacin was isolated from burn wounds of eight pati ents on a burns ward of a hospital in Dehli, India. The organism, which had probably been spread from patient to patient on staff hands, produced the extended-spectrum beta-lactamase SHV-5 and the aminoglycoside-modifying enz ymes AAC(3)II + AAC(6'). The strain was not isolated from stool cultures of any of the patients or staff, apart from the index patient who had a histo ry of diarrhoea and fever before admission. The outbreak ended in three wee ks, after the implementation of strict handwashing. This is the first repor t of SHV-5 beta-lactamase in Salmonella spp. and also the first report of S HV-5 in India. The extended-spectrum beta-lactamases that have been reporte d in Salmonella spp. now include the Group 2be enzymes SHV-2, SHV-5, TEM-3, TEM-25, TEM-27, CTX-M2, PER-1 and PER-2, and the Group 1 enzymes DHA-1 and CMY-2. The types of extended-spectrum beta-lactamases produced by salmonel las, their association with aminoglycoside resistance and their geographica l distribution are now similar to those seen in klebsiella. Increasing anti biotic resistance in these organisms is reducing therapeutic options for th e treatment of invasive disease.