Multidrug-resistant Acinetobacter lwoffii infection in neonatal intensive care units

Aim: To describe the clinical, bacteriological features, and outcome of Acinetobacter lwoffii infection in the neonatal population. Method: We retrospectively reviewed the medical records of four neonatal cases of A. lwoffii infection admitted to the Hat Yai Hospital, January 2005 to December 2009. Results: Four cases (one in 2007, and three in 2008) were identified as having A. lwoffii infection. Of the four cases, three presented with late-onset infection (after 72 hours of age), while 1 presented with early-onset (within the first 72 hours of age). All cases were inserted with umbilical catheters, required positive pressure mechanical ventilation, and had been treated previously with antibiotic drugs at time of diagnosis. Antimicrobial susceptibility testing of seven isolates (three in blood, three in sputum, and one in cerebrospinal fluid) was performed using the disk diffusion method. The most tested isolates were susceptible to netilmicin, imipenem, cefoperazone/sulbactam, while most were simultaneously generally resistant to amikacin, gentamicin, ceftazidime, ceftriaxone, cefepime, ciprofloxacin, and clindamicin. The treatment of A. lwoffii infection in the four cases varied. Only one case was successfully treated with imipenem, while three cases died from severe ventilator-associated pneumonia, and severe sepsis. Conclusion: This study increases awareness of A. lwoffii infection in the neonatal population, particularly in premature infants with several risk factors for nosocomial infection, including central intravascular catheters and prolonged mechanical ventilation.