title: Risk factors for complicated varicella infection in pediatric oncology patients at a tertiary health care facility in Pakistan.
abstract: BACKGROUND
  Varicella zoster infection (VZI) is well recognized as a potential cause of morbidity and mortality in immunocompromised pediatric oncology patients (POP). The purpose of this study was to describe the clinical profile and risk factors for complications and outcomes of VZI in POP treated with acyclovir.
  
  
  METHODS
  Medical records of all POP with a discharge diagnosis of VZI over a period of seven years (2005-2011) were reviewed. The demographic features, underlying malignancy, risk factors for VZI, complications, and outcomes were recorded.
  
  
  RESULTS
  Thirty-six POP with VZI were identified. Leukemia was the most common underlying malignancy (n = 20, 58.8%), followed by lymphoma (n = 7, 20.6%) and solid organ tumors (n = 7, 20.6%). Most of the cases (41%) were observed in children under five. All patients were treated with acyclovir. Varicella-related complications developed in 10 (29%) patients. The most frequent complication was bloodstream infection (n = 3, 8.8%), followed by pneumonia (n = 2, 5.9%), skin infection (n = 2, 5.9%), hepatitis, renal failure, and encephalitis. Independent risk factors associated with complications were age < five years, weight for age < fifth percentile, delay in seeking care (> seven days after onset of symptoms) and severe neutropenia (ANC < 500/cm). One child died secondary to varicella encephalitis.
  
  
  CONCLUSIONS
  Our data suggests that young age, poor health-seeking behavior, severe neutropenia, and being underweight are the major risk factors for the development of varicella-related complications in POP in developing countries. These complications could be favorably modified through active immunization of immunocompetent children.
authors: Aga Khan University, Karachi, Pakistan. matloob.alam@aku.edu.
authors: Muhammad Matloob
authors: MM
authors: Alam
authors: Farah Naz
authors: FN
authors: Qamar
authors: Zalan Wahid
authors: ZW
authors: Khan
authors: Vikram
authors: V
authors: Kumar
authors: Naureen
authors: N
authors: Mushtaq
authors: Zehra
authors: Z
authors: Fadoo
mesh_terms: D000212:Acyclovir / Q000627:therapeutic use; D000293:Adolescent; D000998:Antiviral Agents / Q000627:therapeutic use; D002644:Chickenpox / Q000150:complications / Q000175:diagnosis / Q000188:drug therapy*; D002648:Child; D002675:Child, Preschool; D006801:Humans; D016867:Immunocompromised Host; D007223:Infant; D016015:Logistic Models; D009369:Neoplasms / Q000150:complications / Q000276:immunology*; D010154:Pakistan; D012189:Retrospective Studies; D012307:Risk Factors; D012874:Skin Diseases, Infectious / Q000188:drug therapy / Q000821:virology; D062606:Tertiary Care Centers
chemical_list: D000998:Antiviral Agents; D000212:Acyclovir