Poor positive predictive value of influenza-like illness criteria in adult transplant patients: a case for multiplex respiratory virus PCR testing.
BACKGROUND
Respiratory viral infections (RVIs) are a significant cause of morbidity and mortality among transplant patients. The CDC's influenza-like illness (ILI) criteria (fever ≥100°F with cough and/or sore throat) are a screening tool for influenza with unknown applicability to the transplant population.


METHODS
We reviewed all respiratory virus PCR tests performed on adult patients with a history of solid organ (SOT) or stem cell transplantation (HSCT) during the 2012-2013 influenza season. The positive (PPV) and negative predictive values (NPV) of ILI criteria were calculated.


RESULTS
Of 126 transplant patients (66 HSCT, 60 SOT), 54 (42.8%) tested positive for an RVI by PCR: 24 influenza and 30 non-influenza. Of 30 patients who met ILI criteria, 12 (40%) were positive for influenza. The PPV and NPV of ILI for influenza were 50% and 82.4%, respectively. Mortality was low (3.7%), but morbidity was high (14.8% required ICU stay) among transplant patients diagnosed with RVI.


CONCLUSIONS
Influenza and non-influenza RVIs are associated with significant morbidity among transplant patients. CDC ILI criteria correlate poorly with PCR-positive cases of influenza in transplant patients, but may be useful in excluding the diagnosis. Routine RVI PCR testing is recommended for better diagnosis and improved antiviral use in transplant patients with suspected RVI.
Division of Infectious Diseases, Department of Medicine, State University of New York at Buffalo, Buffalo, NY, USA.
Jonathan A
JA
Claus
Division of Infectious Diseases, Department of Medicine, Rush University Medical Center, Chicago, IL, USA.
Aimee C
AC
Hodowanec
Division of Infectious Diseases, Department of Medicine, Rush University Medical Center, Chicago, IL, USA.
Kamaljit
K
Singh
D000328:Adult; D000368:Aged; D004279:DNA, Viral / Q000032:analysis; D003661:Decision Support Techniques; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007251:Influenza, Human / Q000175:diagnosis* / Q000209:etiology; D008297:Male; D008875:Middle Aged; D060885:Multiplex Polymerase Chain Reaction; D016377:Organ Transplantation; D009975:Orthomyxoviridae / Q000235:genetics / Q000302:isolation & purification; D011183:Postoperative Complications / Q000175:diagnosis*; D011237:Predictive Value of Tests; D012141:Respiratory Tract Infections / Q000175:diagnosis; D012189:Retrospective Studies; D020133:Reverse Transcriptase Polymerase Chain Reaction; D033581:Stem Cell Transplantation
D004279:DNA, Viral
ILI criteria; influenza; influenza-like illness; respiratory virus; transplantation