Clinical impact of timely reporting of IgM for West Nile Virus.

BACKGROUND: In 2002 diagnostic testing for West Nile Virus (WNV) infection was not ideal because commercial products were unavailable. Although testing was performed without charge by public health (PH), testing is not intended to be used for patient management and generally results are not available in a timely or reliable manner. OBJECTIVES: This study was conducted to determine the clinical impact of having WNV serology available by a diagnostic laboratory within a few days of sample collection. STUDY DESIGN: An IgM immunoassay (FT, from Focus Technologies) was performed August 13, 2003 to October 31, 2003 Monday, Wednesday and Friday in our hospital's virology laboratory with split sample testing at PH. All results (positive and negative) were called to physicians. RESULTS AND CONCLUSIONS: Turn-around time for the FT assay was within 0-3 days; for PH, it was approximately 8 days. Of 95 samples, 6 were positive and 89 negative. For the FT negative samples, all were concordant with PH, but four FT positive samples (three sera and one cerebrospinal fluid) were discrepant. After resolution of the discrepancies, the FT test had a sensitivity of 100% and a specificity of 99%. Physicians reacted positively to having results faster. Fifty-eight percent of the results had clinical impact, 22% had undetermined impact, 13% were patient requests, and 4% had no impact. Concluding, the FT assay is 100% sensitive and 99% specific and in 58% there was clinical impact for WNV reporting in a timely manner.

Improved antimicrobial interventions have benefits.

Studies have shown benefits to patients from improved interventions involving antimicrobial therapy. The purpose of the present study was to evaluate prospectively the impact of improved interventions by (i) the use of TheraTrac 2, a computer software program which electronically links susceptibility testing results immediately to the pharmacy and alerts pharmacists of potential interventions, and (ii) the education of pharmacists involving microbiologic topics. The study group had the new intervention program. The control group had interventions performed the way that they had previously been done by manually reviewing hard copies of susceptibility testing data. In a 5-month period, all inpatients whose last names began with A to K were the study group; inpatients whose last names began with L to Z were controls. Three analyses were done; one analysis (analysis A) involved only patients with interventions, one analysis (analysis B) involved all patients for whom antimicrobial testing was done and who were matched for diagnosis-related groups (DRGs), regardless of whether an intervention occurred, and one analysis (analysis C) involved these DRG-matched patients by using severity-adjusted data. In analysis A, the study group had a 4.8% decreased rate of mortality, an average of a 16.5-day decreased length of stay per patient, and $20,886 decreased variable direct costs per patient. None of these differences was statistically significant. In analysis B, the study patients had a 1.2% higher mortality rate (P = 0.741), an average of a 2.7-day decreased length of stay per patient (P = 0.035), and $2,626 decreased variable direct costs per patient (P = 0.008). In analysis C, the study patients had a 1.4% lower mortality rate, a 1.2-day decreased length of stay per patient, and $1,466 decreased variable direct costs per patient. In conclusion, the institution of this program caused substantial cost savings.

R-Mix cells are faster, at least as sensitive and marginally more costly than conventional cell lines for the detection of respiratory viruses.

OBJECTIVE: To evaluate shell vials of R-Mix, a combination of mink lung cells and human adenocarcinoma cells (strains Mv1Lu and A549, respectively, Diagnostic Hybrids, Athens, OH) to detect respiratory viruses from prospective clinical respiratory specimens and frozen stocks. STUDY DESIGN: We compared the performance of R-Mix to conventional culture (CC) using tubes of PMK, Hep-2, and MRC5 to detect respiratory viruses from fresh clinical specimens. For each respiratory specimen submitted to virology, two shell vials of R-Mix were inoculated and examined twice (generally after 24 and 48 h) by an indirect test with a pool of immunofluorescent antisera to influenza A and B, adenovirus, parainfluenza 1-3 and RSV (DAKO, Carpinteria, CA). If positive, testing with monoclonal antisera was done. CCs were incubated for 10 days, examined daily for cytopathological effect, hemadsorbed twice and stained if positive. Cost comparison was done. Lastly, respiratory viruses frozen from previous years were inoculated onto R-Mix. RESULTS: R-Mix was positive for all 29 frozen virus stocks. In the clinical trial, 396 prospective specimens were inoculated into R-Mix and CC. R-Mix identified 21 specimens as respiratory virus positive; CC identified 19. Turn-around time of R-Mix for positive specimens was 1.4 days; for CC it was 5.2 days. Turn-around time of R-Mix for all specimens (positive and negative) was 2.0 days; for CC it was 9.8 days. The overall cost of R-Mix was approximately 11% more than that of CC. CONCLUSION: R-Mix enabled rapid identification of all the frozen virus stocks representing the seven major respiratory viral groups. When compared to CC, R-Mix was slightly more sensitive than three cell lines (four tubes) used in CC but it was several days faster.

Clinical and financial benefits of rapid detection of respiratory viruses: an outcomes study.

To assess the expected benefits of rapid reporting of respiratory viruses, we compared patients whose samples were processed using standard techniques such as enzyme immunoassays, shell vial assays, and culture tube assays (year 1) to patients whose samples were processed with the same standard techniques in addition to immunofluorescent testing (FA) directly on cytocentrifuged samples (year 2). The cytospin FA screened for influenza A and B viruses, respiratory syncytial virus (RSV), parainfluenza viruses 1 to 3, and adenovirus (DAKO Diagnostics Ltd.). The specificity of the cytospin FA for all viruses was 100%. The sensitivities for influenza A virus and RSV were 90 and 98%, respectively, but the sensitivities for influenza B virus and adenovirus were unacceptable (14.3 and 0%, respectively). However, since the former viruses account for >85% of our isolates from clinical specimens, the cytospin FA is an excellent screening test since the positive result was available within hours. The mean turnaround time for all positive viruses was 4.5 days in year 1 and 0.9 day in year 2 (P = 0.001). This rapid reporting resulted in physicians having access to information sooner, enabling more appropriate treatment. The mean length of stay in the hospital for inpatients with respiratory viral isolates was 10.6 days for year 1 versus 5.3 days for year 2. Mean variable costs for these patients was $7,893 in year 1 and $2,177 in year 2. After subtracting reagent costs and technological time, the savings in variable costs was $144,332/year. Summarizing, the cytospin FA markedly decreased turnaround time and was associated with decreased mortality, length of stay, and costs and with better antibiotic stewardship.

Clinical and financial benefits of rapid bacterial identification and antimicrobial susceptibility testing.

To assess the expected clinical and financial benefits of rapid reporting of microbiology results, we compared patients whose cultured samples were processed in the normal manner to patients whose samples were processed more rapidly due to a minor change in work flow. For the samples tested in the rapid-reporting time period, the vast majority of bacterial identification and antimicrobial susceptibility testing (AST) results were verified with the Vitek system on the same day that they were available. This time period was called rapid AST (RAST). For RAST, a technologist on the evening shift verified the data that became available during that shift. For the control time period, cultures were processed in the normal manner (normal AST [NAST]), which did not include evening-shift verification. For NAST, the results for approximately half of the cultures were verified on the first day that the result was available. The average turnaround time for the reporting of AST results was 39.2 h for RAST and 44.4 h for NAST (5.2 h faster for RAST [P = 0.001]). Subsequently, physicians were able to initiate appropriate antimicrobial therapy sooner for patients whose samples were tested as part of RAST (P = 0.006). The mortality rates were 7. 9 and 9.6% for patients whose samples were tested as part of RAST and NAST, respectively (P = 0.45). The average length of stay was 10. 7 days per patient for RAST and 12.6 days for NAST, a difference of 2.0 days less for RAST (P = 0.006). The average variable cost was $4, 927 per patient for RAST and $6,677 for NAST, a difference of $1,750 less per patient for RAST (P = 0.001). This results in over $4 million in savings in variable costs per year in our hospital.

Recovery of Histoplasma capsulatum from BACTEC TB media.

From 1990 through 1994, we fortuitously isolated Histoplasma capsulatum from six patients with AIDS whose specimens of blood were processed by the BACTEC system using Middlebrook broth selective for acid-fast bacilli (13A medium). Growth indices became positive after an average of 17 days of incubation (range, 11 to 20 days). No acid-fast bacilli were seen, but small budding yeasts characteristic of H. capsulatum were present.

Susceptibility testing of topical antibacterials against methicillin-resistant Staphylococcus aureus.

Methicillin-resistant Staphylococcus aureus (MRSA) isolates that were collected from 44 consecutive patients during 1 year in a community hospital were tested for susceptibility to five commonly used topical antibacterial agents. Agar-well susceptibility testing, which was based on zones of inhibition, was used to compare the effectiveness of the antibacterials against MRSA. Nitrofurazone was effective in inhibition of bacterial growth and was relatively inexpensive. Mupirocin was found to be effective but more costly for treatment of MRSA. Varying degrees of susceptibility to silver sulfadiazine, mafenide acetate, and bacitracin were noted in the cultures that were obtained at this medical center. On the basis of our findings from susceptibility tests compared with those of another center, we recommend that all hospitals undertake topical sensitivity testing of their MRSA isolates. Appropriate and effective topical antibacterial therapy can then be planned within each center.

Pulmonary phaeohyphomycosis in a patient with hemoptysis.

A 79-year-old retired schoolteacher had a history of bronchiectasis. She developed recurrent hemoptysis requiring multiple blood transfusions. Exophiala dermatitidis was cultured repeatedly from bronchial lavages. To our knowledge, this is the first documented case of isolated pulmonary phaeohyphomycosis due to E dermatitidis, and it was successfully treated with amphotericin B and 5-fluocytosine.

Studies on the role of the famiy unit in the transmission of trachoma.

Rates of trachoma infection of family members were compared for two groups of index cases; all were infants about 1 year old observed over a period of several months in a previous study. Group A infants were consistently infected with trachoma, and Group B infants were not infected with trachoma. On the average, 50% of Group A family members had active infection (as determined by trachoma inclusions in their conjunctival cells) and 80% of the siblings within 6 years of age to the index cases were infected. Only 9% of Group B family members had active trachoma, and 20% of the siblings within 6 years of age to the index case were infected. This study suggests intrafamilial spread of trachoma.