[Pneumocephalus caused by neonatal Enterobacter cloacae infection in a case]

Gas-containing encephalo-meningitis is very rare. There have only been a few cases reported in the literature. The majority of neonatal cases reported in literature died. We report a case of a 5-day-old neonate who developed diffuse pneumocephalus from Enterobacter cloacae septicemia and intracranial infection.

This neonate was initially treated with penicillin and mezlocillin. He also received phototherapy, intravenous infusion, correction of acidosis and other supportive therapy. Complete blood count, C-Reactive protein, cranial CT scan, blood culture, cerebrospinal fluid culture and biochemistry were tested repeatedly.

This neonate's condition deteriorated after admission. He developed respiratory distress, increased muscle tone and decreased level of consciousness. His WBC and C-reactive protein were elevated, while blood gas, electrolytes, liver enzymes and renal function were within normal range initially. Cranial CT scan was done which demonstrated diffuse pneumocephalus. He was transferred to a higher level hospital for further management at the request of the family. Blood culture done in our hospital subsequently showed growth of Enterobacter cloacae. The infant developed seizures and further deterioration in level of consciousness after transfer. Antibiotics were switched to penicillin and ceftizoxime. Cranial CT scan repeated 2 days after transfer showed hydrocephalus and some resolution of pneumocephalus. Cerebrospinal fluid (CSF) was aspirated from the lateral ventricles two weeks after admission. CSF culture also showed growth of Enterobacter cloacae. Antibiotic was switched to imipenem according to antibiotic sensitivity. His general condition was improved. Blood and CSF cultures were negative 1 month after admission. His head circumference at discharge was 34.6 cm. Repeat cranial CT scan at 4 month of age demonstrated severe hydrocephalus, diffuse leukomalacia and calcification. This infant suffered significant neurodevelopmental deficit. Muscle tone was diffusely increased. Head circumference at 9 month of age was 48.4 cm.

This case suggests the importance of Enterobacter cloacae infection in the newborns. Our analysis of 34 cases of Enterobacter cloacae infection showed that 93.75% - 100% were sensitive to quinolones, 94.12% were sensitive to imipenem, 73.33% were sensitive to gentamicin, 50% were sensitive to piperacillin-tazobactam. Enterobacter cloacae is generally not sensitive to penicillin, first and second generation cephalosporins (0 - 21.4%). Enterobacter cloacae septicemia and intracranial infection in neonates have a high mortality rate and can result in severe neurodevelopmental deficit in survivors.