The diagnosis of adenovirus infection on clinical grounds alone is sometimes difficult and now chromatographic immunoassay tests have begun to be available for point-of-care use.

Adenovirus is among the most common causes of upper respiratory tract infections in febrile pediatric outpatients throughout the year and rapid, accurate diagnosis is important because adenoviral diseases are often associated with prolonged, high-grade fever.

Scientists at the Hiroshima Prefectural Technology Research Institute (Japan) conducted a prospective study between September 2008 and July 2012 to determine whether nasopharyngeal aspirate (NPS) and throat swab (TS) specimens from individual patients could be compared with regard to usefulness for adenovirus detection.

One pediatrician collected TS and NPA specimens in parallel from outpatient children suspected of having adenovirus infection and performed the rapid diagnosis using a chromatographic immunoassay test, the ImmunoAce Adeno (TAUNS Laboratories, Inc.; Numazu, Japan). TS and NPA were tested in separate identical devices and each NPA swab was prepared after being dipped in NPA fluid. Aliquots of NPAs were stored at -70 °C until tested with culture and real-time polymerase chain reaction (PCR) assays to detect and identify adenovirus.

Among the 309 children enrolled, real-time PCR assay, which did not distinguish among serotypes, identified 153 patients with adenovirus and these were considered to be adenovirus-infected patients. Of these 153 patients, viral cultures identified 139 patients with adenovirus, including six serotypes, accounting for 90.8% of the adenovirus detection rate. Among the 153 adenovirus-positive specimens, based on real-time PCR findings, the sensitivities of the rapid test ImmunoAce Adeno were 91.5% for TS and 90.8% for NPA.

The authors concluded that the diagnostic accuracy between TS and NPA specimen types for the rapid diagnosis of adenovirus infections, and the detection rates between the two specimen types were nearly equivalent. Throat swabs are commonly used for the rapid diagnosis of adenoviral infections, while NPAs are routinely used for rapid detection of influenza virus. The present findings will be helpful for pediatricians in primary care clinics because they may be able to use the remaining NPA specimen for the detection of adenovirus or other respiratory viruses in cases when an influenza-negative result is unexpectedly obtained. The study was published on November 12, 2014, in the journal Diagnostic Microbiology and Infectious Disease.

Related Links:
Hiroshima Prefectural Technology Research Institute
TAUNS Laboratories