Salmonella enterica subsp. arizonae is a common gut inhabitant of reptiles, with snakes as the most common reservoir. Though human cases due to this organism are exceedingly rare, it may infect young infants and immunocompromised individuals with a history of intimate associations with reptiles. Gastroenteritis is the most common presentation; others include peritonitis, pleuritis, osteomyelitis, meningitis, and bacteremia. We report a fatal case of S. enterica subsp. arizonae gastroenteritis in a 3-month-old child with microcephaly, with a review of earlier cases and problems encountered in identification of this rare human pathogen.
CASE REPORTA 3-month-old female child presented to the Emergency Unit at Ram Manohar Lohia Hospital, New Delhi, India, with a history of fever and cough for 20 days and diarrhea with mucus and blood for 15 days. There was no history of similar illness in other family members or in the community. On admission, the child, who had microcephaly, appeared highly irritable and had tachypnea and bilateral crepitations. The spleen and liver were just palpable, and there was a rash all over the body. The patient was diagnosed as having pneumonia with persistent diarrhea. A fecal sample was sent for routine culture and microscopic examination, and the patient was empirically started on broad-spectrum antibiotics (ampicillin, cefotaxime, and amikacin). Investigations revealed a hemoglobin level of 11.0 g%, a total leucocyte count of 11,500/ml, and an erythrocyte sedimentation rate of 100. A urine culture was sterile, and cerebrospinal fluid biochemistry and cytology showed no abnormality. The chest X ray showed infiltration in both lungs, while the skull X ray was normal.The routine microscopic examination of feces did not reveal the presence of any protozoan or helminth. While fecal cultures grew a non-lactose-fermenting motile organism, the routine biochemical tests (indole, triple-sugar iron agar, citrate, urea, mannitol, and motility) for this isolate were obfuscating.