Evaluation of a multiplex ligation-dependent probe amplification assay for the detection of respiratory pathogens in oncological patients.

BACKGROUND: Respiratory tract infections are widespread and may cause significant morbidity and mortality in immunosuppressed populations such as oncological patients. OBJECTIVES: The RealAccurate Respiratory RT PCR Kit covering 14 respiratory viruses was compared to the RespiFinder Smart22, a broad-spectrum multiplex ligation-dependent probe amplification (MLPA) test, targeting 22 viral and bacterial respiratory pathogens. STUDY DESIGN: After verification of its analytical performance, the clinical performance of the RespiFinder Smart22 was evaluated by re-analysis of 96 respiratory samples from oncological patients. Additionally, the time to result (TTR) of both methods was compared. RESULTS: The analytical performance of the RespiFinder Smart22 fulfilled all previously specified criteria. Concordant results in both assays were achieved in 74.0% of all clinical specimens and in 91.2% when only positive results were taken into account. The RespiFinder Smart22 yielded additional results in a total of 22 (22.9% of 96) samples due to higher test sensitivity and a broader, highly multiplexed spectrum of pathogens. The TTR of a typical routine test consisting of three samples were 206 and 356 min for the RealAccurate Respiratory RT PCR Kit and the RespiFinder Smart22, respectively. However, hands-on time was reduced by 59.0% applying the MLPA method. CONCLUSIONS: In our hands, the RespiFinder Smart22 showed excellent analytical performance while hands-on time was halved in comparison to the RT PCR method. Regarding the clinical evaluation, the MLPA method provided additional results in 22.9% (22/96) of specimens due to its comprehensive format, higher test sensitivity and the capability to detect 22 pathogens compared to 14 with the RealAccurate Respiratory RT PCR Kit.

Antiviral treatment of chronic hepatitis C in clinical routine.

OBJECTIVE: Pegylated interferon plus ribavirin is the standard treatment for chronic hepatitis C. Sustained virological response (SVR) rates of up to 60% are reported in randomized controlled trials, but it is unclear whether the results from such trials are reproducible in the clinical routine setting. We investigated consecutive treatment-naïve chronic hepatitis C patients at our center to examine the efficacy of treatment with pegylated interferon plus ribavirin in clinical routine. MATERIALS AND METHODS: Between 2000 and 2006 we treated a total of 219 patients with pegylated interferon alpha (2a or 2b) and ribavirin (800-1200 mg/d). Among them, 34.8% of patients infected with HCV genotypes 1/4/6 and 18.4% of those with genotypes 2/3 had advanced fibrosis or cirrhosis (F3-F4). For analysis of outcome we subdivided our series into two groups of patients: those who fulfilled standard inclusion criteria in randomized controlled trials and those who did not. RESULTS: The overall SVR rate was 44.3%. In patients with F0-F2 an SVR was achieved in 52.5%; in those with F3-F4 the SVR rate was 20.8%. In patients infected with genotypes 1/4/6 the SVR rate was 35.4% (SVR: F0-F2 47.7%; F3-F4 19.6%); in those with genotypes 2/3 the rate was 67.8%. The SVR rate in patients with unfavorable baseline factors was significantly lower (32.4% vs. 50%; P = 0.017) and they were more likely to be non-responders (30.9% vs. 13.8%). CONCLUSION: In everyday clinical practice, up to one-third of patients show unfavorable baseline factors for antiviral therapy, resulting in worse therapeutic outcome. Differences in therapeutic outcome are influenced by patient selection and by the proportion and severity of the underlying liver disease.