Background: Viral upper respiratory tract infections (URIs) are a significant cause of morbidity in pediatric bone marrow transplant (BMT) patients. The speed and increased sensitivity of the BIOFIRE® Respiratory Panel (BIOFIRE® RP) is valuable but may prompt inappropriate testing. We investigated BIOFIRE® RP usage, test outcomes, and clinical response in our pediatric BMT population to determine whether implementation of testing restrictions are warranted.
Materials/methods: Retrospective data was collected for 682 respiratory specimens tested by BIOFIRE® RP from 214 unique BMT patients between 01/01/2016–01/01/2019. Information including age, underlying conditions, and frequency of BIOFIRE® RP testing were recorded. Data on patients with multiple specimens tested within a 14-day period were also examined to determine consistency of target detection, the presence of URI symptoms, and modifications in management.
Results: 312/682 (45.8%) specimens were positive by BIOFIRE® RP. Detection of rhinovirus/enterovirus (179, 57.3%) was most common, followed by coronaviruses (40, 12.8%), parainfluenza (33, 10.6%), and respiratory syncytial virus (19, 6.1%). 66 patients had multiple specimens tested within a 14-day period, consisting of 105 repeat tests on 195 total specimens; of these, the same target was detected in 79 (75.3%) cases. In contrast, 26 (24.7%) patients with additional specimens tested yielded a different result: 13 (6.7%) positive patients became negative and 13 (6.7%) negative patients became positive. In the negative to positive group, the most common target detected was rhinovirus/enterovirus and only five patients were symptomatic during original test and retest. 27% (53/195) of specimens were collected from asymptomatic patients, of these four cases of rhinovirus/enterovirus were detected. BIOFIRE® RP result informed addition of antiviral agents. No de-escalation of antimicrobial therapy was observed regardless of BIOFIRE® RP result. Influenza detected in one patient prompted chemotherapy suspension and there were no recorded instances in which BIOFIRE® RP results delayed BMT.
Conclusions: There is a high incidence of inappropriate BIOFIRE® RP testing in asymptomatic BMT patients and results seldom influence patient management. Moreover, testing of additional specimens over a 14-day period infrequently provides useful information. These findings support implementing diagnostic stewardship measures including potentially limiting repeat testing within a 14-day period without negatively affecting patient outcome.