title: Search of Unknown Fever Focus Using PET in Critically Ill Children With Complicated Underlying Diseases.
abstract: OBJECTIVE
  PET/CT with F-fluorodeoxyglucose can be used to image cellular metabolism and has been used for evaluating fever of unknown origin in adults. However, there are limited studies about the role of F-fluorodeoxyglucose PET/CT in evaluation of fever of unknown origin in critically ill children, especially those presenting with complicated underlying diseases under treatment. Here, we report our preliminary experience using F-fluorodeoxyglucose PET/CT in this specific group of patients.
  
  
  METHODS
  Retrospective observational study.
  
  
  METHODS
  PICUs of a university hospital.
  
  
  METHODS
  Nineteen critically ill children (mean age, 5.7 yr old) with complicated underlying diseases requiring intensive care support underwent F-fluorodeoxyglucose PET/CT to evaluate fever of unknown origin. The median hospitalized stay was 34 days (range, 15-235 d) and fever of at least 7 days (mean, 21.6 d; range, 7-52 d). The PET scan was advocated after all routine microbiology, and conventional imaging showed negative or inconclusive results.
  
  
  METHODS
  None.
  
  
  RESULTS
  The F-fluorodeoxyglucose PET/CT findings (blinded to the final clinical diagnosis) were compared with final histopathology, culture, serology results, or follow-up imaging. A final diagnosis was made in 16 patients (84.2%). F-fluorodeoxyglucose PET/CT accurately localized the source of fever in 14 patients, confers to a sensitivity of 87.5% (14 of 16; 95% CI, 0.604-0.978). A false-positive scan in a patient led to subsequent unnecessary investigations. Two false-negative F-fluorodeoxyglucose PET/CT images were later attributed to relapse of underlying disease in the bone marrow and renal abscesses, respectively. In the other two patients where F-fluorodeoxyglucose PET/CT also showed negative findings, fever subsided shortly thereafter without treatment.
  
  
  CONCLUSIONS
  Our preliminary experience suggests that F-fluorodeoxyglucose PET/CT may be clinically beneficial in evaluating fever of unknown origin in children with complicated underlying diseases mandating intensive support in ICUs if usual investigative methods are unsuccessful. Further large prospective studies are needed to validate these findings.
authors.affiliation: 1Department of Pediatrics, Mackay Memorial Hospital and Mackay Junior College of Medicine, Nursing and Management, Taipei, Taiwan. 2Department of Nuclear Medicine, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan. 3Institute of Occupational Medicine and Industrial Hygiene, College of Public Health, National Taiwan University, Taipei, Taiwan. 4Department of Pediatrics, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan. 5Department of Nuclear Medicine, National Taiwan University Hospital, Yun-Lin Branch, Douliou City, Taiwan. 6Institute of Epidemiology and Preventive Medicine, College of Public Health, National Taiwan University, Taipei, Taiwan.
authors.forename: Lung
authors.initials: L
authors.lastname: Chang
authors.forename: Mei-Fang
authors.initials: MF
authors.lastname: Cheng
authors.forename: Shiann-Tarng
authors.initials: ST
authors.lastname: Jou
authors.forename: Chi-Lun
authors.initials: CL
authors.lastname: Ko
authors.forename: Jei-Yie
authors.initials: JY
authors.lastname: Huang
authors.forename: Kai-Yuan
authors.initials: KY
authors.lastname: Tzen
authors.forename: Rouh-Fang
authors.initials: RF
authors.lastname: Yen
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D015897:Comorbidity; D016638:Critical Illness; D003937:Diagnosis, Differential; D005260:Female; D005335:Fever of Unknown Origin / Q000150:complications / Q000000981:diagnostic imaging*; D019788:Fluorodeoxyglucose F18 / Q000008:administration & dosage*; D006785:Hospitals, University; D006801:Humans; D007223:Infant; D015278:Intensive Care Units, Pediatric; D007902:Length of Stay; D008297:Male; D049268:Positron-Emission Tomography / Q000379:methods*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D019788:Fluorodeoxyglucose F18