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OBJECTIVE: Rapid detection of respiratory syncytial virus (RSV) infection can assist clinicians in decisions regarding antiviral therapy with ribavirin as well as instituting infection control measures. The Abbott TestPack RSV is a rapid RSV detection immunoassay that can be performed on respiratory secretions in 20 to 30 minutes without special laboratory equipment. The purpose of this study was to evaluate housestaff performance of the TestPack RSV at bedside as compared with laboratory testing of aliquots of the same specimen by tissue culture inoculation, direct fluorescent antibody (DFA) testing and TestPack RSV. METHODS: During the 1991 through 1992 RSV season, 137 nasopharyngeal aspirates or washes obtained from pediatric patients < 4 years of age suffering from acute respiratory disease were assayed by the Food and Drug Administration-approved TestPack RSV as well as conventional tube culture and DFA testing. RESULTS: 66 of 137 (48%) specimens were positive for RSV as defined by: isolation and DFA-positive (n = 48) and DFA testing positive with negative culture (n = 18); blocking assay experiments using TestPack RSV confirmed culture-negative DFA-positive specimens as positive in 8/8 instances in which material for retesting was available. Using these definitions, the sensitivity and specificity for the assays were: housestaff TestPack RSV: 92%, 93%; laboratory TestPack RSV: 97%, 98%; virus isolation: 72%, 100%. CONCLUSION: From these data, it appears that the TestPack RSV EIA in the field setting is reliable, although laboratory confirmation of results is important.

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The neutralization test is commonly used in clinical virology laboratories for the identification by serotype of adenovirus isolates. In an effort to conserve reagents and reduce the amount of time in the performance of this assay, we evaluated the significance of differential cytopathic effects for the presumptive identification of lower-numbered adenovirus serotypes that are commonly encountered in the clinical setting. Utilizing the human lung carcinoma (A549) cell culture as our indicator system, two viral induced monolayer degenerations (i.e., cytopathic effects or CPEs) were recognized. Among our wild and the laboratory adapted (i.e., ATCC) adenovirus isolates tested in this study, serotypes 1, 2, 4, 5, 6, 8, 11, 19, 21, 27, and 31 were expectedly characterized by the typically enlarged, rounded, and refractile cells, which eventually aggregated into irregular 'grape-like' clusters. Adenovirus types 3 and 7, however, were characterized by the development of distinct intranuclear inclusions, a flattening and then a web or net-like monolayer degeneration. Differences in the intensity of intranuclear granulation were related by electron microscopy to differences in the quantity of viral crystalline aggregates within the host cell nucleus. A presumptive identification of the commonly encountered adenovirus serotypes 3 and 7 prior to the performance of the neutralization test would result in a conservation of type-specific antiserum, a decreased use of cell cultures and medium, and lastly, reduced medical technologist workload.

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One hundred twelve peripheral blood specimens were tested for the presence of cytomegalovirus (CMV) by the tube culture indirect immunoperoxidase (TC-IPA) procedure, the shell vial assay [shell vials were pre- and postinoculation treated with medium containing 2 of 10% fetal bovine serum (FBS) or 100 micrograms% cortisol] (SV-IFA), and conventional (MRC-5) tube cultures (TC-CPE). CMV was detected in 25 (22%) of the 112 specimens tested by at least one of these methods. The detection/isolation of CMV among the 25 positive specimens in shell vials maintained with 2% FBS, 100 micrograms% cortisol + 2% FBS, and 10% FBS was 36, 44, and 52%, respectively. Detection/isolation of the virus from blood by TC-IPA and TC-CPE was 52% and 76%, respectively. A significantly greater CMV detection rate occurred using TC-CPE compared to SV-IFA treated with medium supplemented with an FBS concentration of 2% (P = .0132), but not medium containing the higher serum supplement or the glucocorticoid (P greater than .05). Differences in the identification of a CMV viremia were observed by IPA, SV-IFA, and TC-CPE methodologies on a patient-to-patient basis, denoting the necessity of incorporating each methodology into the CMV screening panel. Demographic analysis of 82 AIDS patients showed a CMV viremia prevalence of 9% (2/28) in intravenous drug users, 57% (27/47) in homosexual patients, and 22% (2/9) in heterosexual and transfusion patients. Overnight (24 hr) storage of whole blood at 4 or 24 degrees C, respectively, reduced CMV recovery by 40% and 65%, when tested by TC-CPE.(ABSTRACT TRUNCATED AT 250 WORDS)

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