It is unclear whether findings on chest x-ray (CXR) and complete blood counts (CBCs) can predict H1N1 disease. The objective of this study was to determine if white blood cell (WBC) counts and CXRs can predict H1N1 status.Methods
All adult patients referred to the emergency department at Laniado Hospital suspected to have H1N1 disease and had both a CBC and chest x-ray were included. All chest-rays were interpreted by radiologists blinded to H1N1 status that was determined by 3 polymerase chain reaction sample determinations.Results
The pretest probability for H1N1 disease was 31.4% (73/212). The posttest probability for CXR findings and the combination of CXR findings and WBC counts varied from 10.7% to 42.1%, representing an abnormal CXR as well as an elevated WBC count and both normal tests, respectively.Conclusions
H1N1 status cannot be reliably predicted by chest x-ray and CBC findings.