Keratoconjunctivitis epidemica

Point of care testing: diagnosis outside the virology laboratory

Numerous point-of-care tests (POCTs) are available to diagnose viral infections in both hospital and community settings. The ideal POCT is rapid, sensitive, specific, and simple to perform. This chapter will describe the benefits of POCTs, factors that can influence the accuracy of POCTs and highlight some limitations of POCT strategies. The sensitivity, specificity, and turn-around time of available POCTs are included for common conditions including respiratory viral infections (e.g. influenza, RSV) and blood-borne viral infections (e.g. HIV).

Performance of a new immunochromatographic assay for detection of adenoviruses in children

BACKGROUND

Adenoviruses are a prominent cause of respiratory, ocular, gastrointestinal, and disseminated diseases in healthy and immunocompromised children. An accurate rapid diagnostic assay may impact clinical decision-making.

OBJECTIVES

Evaluate the performance of a new rapid assay for detection of adenoviruses directly in pediatric clinical specimens.

STUDY DESIGN

The rapid assay was performed on adenovirus culture-positive original samples and on an equal number of culture-negative samples matched by patient age and specimen type. Discrepant results were resolved using a polymerase chain reaction (PCR) assay.

RESULTS

200 adenovirus culture-positive and 200 adenovirus culture-negative samples were evaluated from 315 different patients. Overall sensitivity was 55% and specificity was 98.9%. The assay was most sensitive in children 5 years old and younger and most specific in respiratory samples.

CONCLUSIONS

The rapid assay was highly specific for detecting adenovirus infections in children. However, since this rapid assay had only moderate to low sensitivity, samples with negative rapid assay results should have additional testing for adenovirus performed by either viral culture or PCR.

The RPS adeno detector for diagnosing adenoviral conjunctivitis

PURPOSE

To compare the sensitivity, specificity, and accuracy of the RPS Adeno Detector (Rapid Pathogen Screening Inc., South Williamsport, PA) against both viral cell culture with confirmatory immunofluorescence staining (CC-IFA) and the polymerase chain reaction (PCR) for diagnosing adenoviral conjunctivitis.

DESIGN

Prospective, nonrandomized, masked, multicenter clinical trial.

PARTICIPANTS

One hundred eighty-six consecutive patients from 5 clinical centers seeking treatment within 1 week of developing a red eye and thought to have acute conjunctivitis.

METHODS

The RPS Adeno Detector is a 10-minute in-office lateral flow immunoassay. Patients were tested with the RPS Adeno Detector, CC-IFA, and PCR to detect the presence of adenovirus.

MAIN OUTCOME MEASURES

The sensitivity, specificity, and accuracy of the RPS Adeno Detector were assessed for identifying cases of adenoviral conjunctivitis.

RESULTS

Compared with CC-IFA, the RPS Adeno Detector was 88% sensitive and 91% specific at detecting adenoviral conjunctivitis. Using PCR as a reference method, the sensitivity of the RPS Adeno Detector increased to 89% and the specificity increased to 94%. Compared with PCR, CC-IFA was found to be 91% as sensitive and 100% as specific.

CONCLUSIONS

The RPS Adeno Detector demonstrated sufficient sensitivity and specificity to be used in the physician's office for the detection of adenoviral conjunctivitis.