The utility of PET/CT in diagnosing fever of unknown origin: The
experience of a large tertiary medical center
Background: Fever of unknown origin (FUO) is a diagnostic challenge.
Positron emission tomography with computed tomography (PET/CT) is
expensive and not widely available. We aimed to evaluate the diagnostic
yield of PET/CT in the workup of FUO, and identify the patients for whom
this test is most useful. Methods: We reviewed the records of all
patients admitted to Sheba Medical Center from 2013 to 2017 who were
underwent PET/CT for the evaluation of FUO. Results: Of the 128 patients
included, PET/CT was helpful in revealing the cause of FUO in 61 (48%).
A final diagnosis was made in 95 (74%) patients. Of the 128 PET/CT
tests conducted for the workup of FUO, 61 (48%) had true positive
results, 25 (20%) false positive results, 24 (19%) true negative
results, and 18 (14%) false negative results. In a multivariate
analysis, helpfulness of PET/CT was independently associated with weight
loss and low hemoglobin. The calculated test sensitivity was 77%,
specificity was 49%, positive predictive value was 71% and negative
predictive value was 57%. Conclusion: PET/CT is valuable in the
diagnostic workup of FUO. When used as a complementary test, it was
helpful in diagnosing almost half the patients, and especially in those
with low hemoglobin and weight loss.