Don't be falsely reassured if rhinovirus on a PCR viral panel is positive. The incidence of UTI was unchanged if </= 90 days, and the incidence of invasive bacterial infection (IBI) was no different </= 28 days. However, it may prove useful for risk stratifying infants for IBI in the 29 to 90-day age group.
Why does this matter?
We seem to be ordering respiratory viral panels (RV-PCR) more often in pediatric patients. What should we do if it comes back positive for rhinovirus, which may be positive in asymptomatic infants or persistently detectable long after infectious symptoms have resolved? Is it "just a cold?"
Maybe not just a cold
This was a retrospective study of >10,000 infants 1-90 days; >4000 had a RV-PCR. Risk of UTI was the same (about 6%) whether positive or negative for rhinovirus. Risk of IBI was the same in infants </= 28 days whether positive or negative for rhinovirus. But the risk of IBI was much lower (RR 0.52) in rhinovirus-positive infants 29-90 days old. My thoughts are to follow your institutional protocols for risk stratification in the 29-90 day range. But as you develop these protocols, it appears that rhinovirus could be included with RSV, influenza, enterovirus, and others, which are known to be associated with a lower risk of IBI. This type of information could reduce the number of infants who would need LP and be part of a broader strategy to reduce the invasiveness of the fever workup in select, low-risk infants. They stated that rhinovirus "detection could be considered when managing febrile infants in [the 29-90 day] age range, including the decision to perform a lumbar puncture or to admit."
Rhinovirus in Febrile Infants and Risk of Bacterial Infection. Pediatrics. 2018 Jan 17. pii: e20172384. doi: 10.1542/peds.2017-2384. [Epub ahead of print]
Peer reviewed by Thomas Davis, MD.