Mixed-genotypes Infections with Hepatitis C Virus in Hemodialysis Subjects

Mixed-genotypes hepatitis C virus (HCV) infections are normally ignored in chronic hemodialysis patients. The aim of this study is to investigate the prevalence of mixedgenotypes infections among hemodialysis patients in Pahang province, Malaysia. Reverse-transcription and polymerase chain reaction methods were performed using two different sets of primers, targeting the 5’ untranslated region and nonstructural 5B region. Target region base sequences were obtained by direct sequencing. Discrepancy in outcomes from phylogenetic analysis of both regions suggests double infections. Of 40 subjects in eight hemodialysis centres, evidence of mixed-genotypes infections was found in 5 subjects (12.5%) from three different centres. Four patients were infected with mixed genotypes 3 and 1 and one with genotypes 3 and 4. Cases of mixed HCV genotypes infection were considered high among hemodialysis patients in Pahang. However, further investigation is needed to confirm whether they are true mixed infections or perhaps infection with recombinant virus and also to assess the clinicopathologic characteristics of the infection.

The use of multiplex real-time PCR improves the detection of the bacterial etiology of community acquired pneumonia

Community-acquired pneumonia (CAP) is still a major cause of morbidity and mortality especially to children and compromised hosts, such as the old and those with underlying chronic diseases. Knowledge of pathogens causing CAP constitutes the basis for selection of antimicrobial treatment. Previous data have shown that etiological agents can be identified in only up to 50% of patients, but this figure can be improved by using polymerase chain reaction (PCR). This study was designed to evaluate multiplex real-time PCR as a method for rapid differential detection of five bacterial causes of CAP (Streptococcus pneumoniae, Burkholderia pseudomallei and atypical bacterial pathogens namely Mycoplasma pneumoniae, Chlamydophila pneumoniae and Legionella pneumophila) in CAP patients attending Hospital Tengku Ampuan Afzan (HTAA)/ Kuantan, Pahang, Malaysia. Two previously developed multiplex real-time PCR assays, duplex for the differential detection of S. pneumoniae and B. pseudomallei and triplex for the atypical bacterial pathogens, were used to detect a bacterial cause of CAP in blood and respiratory samples. Thus, 46 blood and 45 respiratory samples collected from 46 adult CAP patients admitted to HTAA were analysed by multiplex real-time PCR assays and conventional methods. The microbial etiology of CAP could be established for 39.1% (18/46) of CAP patients by conventional methods and this was increased to 65.2% (30/46) with the additional use of real-time PCR. The most frequently detected pathogens were S. pneumoniae (21.7% - all by PCR alone), Klebsiella pneumoniae (17.3%), B. pseudomallei (13% - 83% of them positive by PCR alone and 17% by both culture and PCR), Pseudomonas aeruginosa (6.5%), M. pneumoniae (6.5% - all by serology), C. pneumoniae (4.3% - all positive by both PCR and serology), L. pneumophila (2.1% - all by PCR alone), Escherichia coli (4.3%). Haemophilus infuenzae, Acinetobacter lwoffii and Acinetobacter baumannii were detected by conventional methods (2.1% for each).