RESUMEN
Background and study aims: Mutations within the major hydrophilic region [MHR] of the hepatitis B surface antigen [HBsAg] have been reported in relation to viral persistence by evasion from vaccine and immunotherapy, severity of liver disease and lack of detection by commercial kits. The aim of this study was to elucidate the circulation of hepatitis B virus [HBV] genotypes, subgenotypes and serotypes in Egypt, with recognition of the pattern and prevalence of MHR mutations possibly occurring during the course of the disease
Patients and methods: Eighty-eight samples from patients with chronic HBV infection were included in the study. The surface protein-encoding gene [S gene] in the HBV genome was subjected to amplification and partial sequencing
Results: Based on phylogenetic analysis, only genotype D was found circulating among patients. The majority of isolates belonged to subgenotype D3 [86.3%], followed by D7 [8%], then D5 [3.4%] and lastly D1 [2.3%]. Two subtypes were identified: ayw2 [97%] and ayw3 [2%]. The 'w' sub-determinant was not defined in one isolate [1%]. A significant proportion of patients [13/88, 14.8%] exhibited mutations in the MHR, 10 of whom harboured mutations in the 'a' determinant region and three outside. The first loop comprised four patients with three mutations [P127S, P127T and Y134F]. The second loop contained six patients, all with one mutation, S143L, which was most frequently encountered in this study [6.8%]
Conclusions: We conclude that genotype D, subgenotype D3 and HBsAg subtype ayw2 are the most common types circulating in Egypt, which account for 100%, 86.3% and 97% of the population, respectively, with a moderate degree of MHR mutations
RESUMEN
Ascitic fluid infections [AFIs] are the frequent complications of advanced liver disease. Bacterial translocation is considered a key step in the pathogenesis of gut-derived bacterial infections; mainly spontaneous bacterial peritonitis [SBP] in cirrhotic patients. Bacterial DNA [bactDNA] in ascitic fluid and serum has been suggested as a surrogate marker for bacterial translocation. We attempted at the isolation and identification of bacteria in ascitic fluid in cirrhotic patients and the assessment of polymerase chain reaction [PCR] in ascitic fluid and serum. Fifty cirrhotic patients having ascites with no signs of infection were included. Ascitic fluid cultures were obtained from patients. Ascitic fluid and serum were subjected to DNA extraction and PCR for the universal amplification of a region of the 16S ribosomal RNA [16S rRNA] gene to detect bactDNA. Bacteria were isolated from 9 [18%] of the ascitic fluid samples, and were mainly Gram-positive bacteria. BactDNA was detected simultaneously in the ascitic fluid and serum of 17 [34%] patients and in the ascitic fluid of only 2 patients. In a single patient with positive ascitic fluid culture no bactDNA was detected in ascitic fluid or serum. By considering AFIs as a positive ascitic fluid culture and/or the presence of bactDNA in the ascitic fluid and/or serum, ascitic fluid culture could detect 9 out of 20 patients with AFIs [45%], PCR of ascitic fluid could detect 19 out of 20 [95%] while PCR of serum could detect 17 out of 20 [85%]. In 10 patients with culture negative non-neutrocytic ascites [CNNNA] bactDNA could be detected in serum and ascitic fluid. AFI can be caused by Gram positive as well as Gram negative organisms. A substantial percentage of cases with CNNNA show bactDNA in serum and ascitic fluid. PCR of ascitic fluid should, therefore, be used in the diagnostic workup of suspected cases of ascitic fluid infections