To the Editors:
We read with great interest the article recently published in The Pediatric Infectious Disease Journal by Thatrimontrichai et al1 regarding risk factors and outcome of carbapenem-resistant Acinetobacter baumannii (CRAB) bacteremia in a neonatal intensive care unit. The results of our recently published data2 support the results of their study. Infection with CRAB was uncommon but had a high mortality in the neonatal intensive care unit. In our center, 9% of late-onset neonatal sepsis cases were caused by Acinetobacter spp. with a mortality of 29%.3 We previously reported a series of 22 neonates who developed A. baumannii bacteremia in our center between January 2005 and December 2010. Of those, 13 cases were CRAB with a mortality of 46%, similar to the 43% reported in their study. The major concern was the pandrug-resistant A. baumannii (PDR-AB) bacteremia that was found in 8 of the 13 CRAB cases, which resulted in 50% mortality. There was no PDR-AB identified in the study of Thatrimontrichai et al. In addition, we found that receiving mechanical ventilation was a risk factor for CRAB bacteremia and ventilator-associated pneumonia occurred in 32% at the time of bacteremia, similar to a report by Punpanich et al4 of CRAB bacteremia in children in Thailand.
Due to a high incidence of PDR-AB bacteremia in our center, we used intravenous colistin combined with meropenem, despite the potential renal toxicity of colistin, because of the limited availability of other effective antimicrobial agents. We also have successful experience with using colistin nebulization for CRAB and PDR-AB pneumonia.5 The pharmacokinetics of intravenous colistin and bronchoalveolar drug values after nebulization therapy in the neonatal population is not fully understood and deserves further study.
Narongsak Nakwan, MD
Department of Pediatrics
Hat Yai Medical Education Center
Hat Yai Hospital
Songkhla, Thailand
Kulkanya Chokephaibulkit, MD
Department of Pediatrics
Division of Infectious Diseases
Faculty of Medicine Siriraj Hospital
Mahidol University
Bangkok, Thailand
REFERENCES
1. Thatrimontrichai A, Apisarnthanarak A, Chanvitan P, et al. Risk factors and outcome of carbapenem-resistant Acinetobacter baumannii bacteremia in neonatal intensive care unit: a case-case-control study. Pediatr Infect Dis J.. 2012 Aug 29. doi: 10.1097/INF.0b013e318270b108.
2. Nakwan N, Wannaro J, Nakwan N, et al. Clinical features, risk factors, and outcome of carbapenem-resistant Acinetobacter baumannii in a Thai neonatal intensive care unit. Asian Biomedicine.. 2012;6:473–479
3. Al-Taiar A, Hammoud MS, Cuiqing L, et al. Neonatal infections in China, Malaysia, Hong Kong and Thailand. Arch Dis Child Fetal Neonatal Ed.. [published online ahead of print August 31, 2012]. doi:10.1136/archdischild-2012-301767
4. Punpanich W, Nithitamsakun N, Treeratweeraphong V, et al. Risk factors for carbapenem non-susceptibility and mortality in Acinetobacter baumannii bacteremia in children. Int J Infect Dis. 2012 Aug 31. doi.org/10.1136/archdischild-2012-301767.
5. Nakwan N, Wannaro J, Thongmak T, et al. Safety in treatment of ventilator-associated pneumonia due to extensive drug-resistant Acinetobacter baumannii with aerosolized colistin in neonates: a preliminary report. Pediatr Pulmonol. 2011;46:60–66
