Occult hepatitis B virus infection in HIV-infected Lebanese patients with isolated antibodies to hepatitis B core antigen.

The presence of hepatitis B virus (HBV) serological markers have been investigated in 101 Lebanese patients (69 men, 32 women; mean age 32.7 +/- 1.7 years) infected with human immunodeficiency virus type 1 (HIV-1). Seven patients (6.9%) were HBsAg carriers compared with 54 patients (53.5%) who had no evidence of exposure to HBV infection. Twenty-four patients (23.8%) had anti-HBc alone as a serological marker compared with four patients who were positive for anti-HBs alone and 12 patients (11.9%) who were anti-HBc and anti-HBs-positive. Occult HBV infection (presence of HBV DNA in the absence of HBsAg) is found to be relatively high (28.7%) in HIV-infected Lebanese patients and the overwhelming majority (83.3%) of those who were positive for anti-HBc alone had a detectable HBV DNA in their serum. However, none of our HIV-positive patients with occult HBV infection had abnormal alanine aminotransferase level, which also raises the question as to whether occult HBV plays a role in the aetiology of liver disease in HIV-infected patients. Further, studies on the association between HBV DNA levels and markers of liver function in addition to data on liver biopsy would help in answering this question.

Occult hepatitis B virus infection in Lebanese patients with chronic hepatitis C liver disease.

Occult hepatitis B virus (HBV) infection, characterised by the presence of HBV infection with undetectable hepatitis B surface antigen (HBsAg), was investigated in 98 Lebanese patients with chronic hepatitis C liver disease and 85 control subjects recruited from eight institutions in different parts of the country. The prevalence of occult HBV infection ranged from 11.9% to 44.4% in hepatitis C virus (HCV)-infected patients and it increased with increasing severity of the liver disease. The overall rate of HBV DNA in our 98 HCV-infected patients was 16.3%. On the other hand, the rate of HBV DNA was 41.0% in anti-HBc alone positive patients compared to only 7.1% in healthy controls who were also anti-HBc alone positive (p < 0.001). Moreover, the prevalence HBV DNA increased with increasing severity of the liver disease, but this increase was only marginally significant and, perhaps, could have been significant if more patients were involved in the study. Although Lebanon is an area of low endemicity for both HBV and HCV, occult HBV infection is common in HCV-infected patients. The presence of HBV DNA, therefore, presents a challenge for the effective laboratory diagnosis of hepatitis B, particularly if polymerase chain reaction (PCR)-based HBV detection methods are not used.

Hepatitis B virus DNA in serum of 'anti-HBc only'-positive healthy Lebanese blood donors: significance and possible implications.

Transmission of HBV infection through transfusion of HBsAg-negative blood has been documented. It is evident that low levels of HBV-DNA remain detectable in serum and liver tissue of some patients who clear HbsAg, and that the detection rate is highest in individuals who are 'anti-HBc positive alone'. This study was designed to assess the frequency and clinical significance of 'anti-HBc alone' in Lebanese blood donors. A total of 5511 blood donor samples from three major hospitals representing most regions of the country were tested for anti-HBc, amongst other screening tests. Samples positive for 'anti-HBc alone' were then tested for HBV-DNA and any positive for HBV-DNA were then genotyped and investigated for hepatitis B viral load. The study showed that 203 (3.7%) of randomly selected Lebanese blood donors were confirmed as 'anti-HBc alone'. Of these, 11 (5.4%) were HBV-DNA positive as detected by nested PCR. All samples had HBV-DNA levels below 400 copies/ml and all were genotype D. It can be concluded that HBV was present, although the circulating amount of virus was below the detectable limit for the assay used. Therefore, routine screening for anti-HBc may be required in Lebanese blood donation centres as an additional preventive measure for controlling transmission of HBV via blood transfusion.

Genotypes of hepatitis C virus (HCV) among positive Lebanese patients: comparison of data with that from other Middle Eastern countries.

Recently we identified hepatitis C virus (HCV) genotype 4 as the principle genotype among Lebanese thalassaemics. In an attempt to confirm the predominance of genotype 4 in Lebanon and perhaps in the Middle East, genotyping was attempted on 142 HCV-infected Lebanese patients from five different hospitals in the country. These included 38 HCV-positive patients with symptomatic liver disease who were referred to gastroenterologists and 104 HCV-positive patients with no symptoms of liver disease: 27 patients with thalassaemia, 30 patients on haemodialysis, 32 multi-transfused and 15 intravenous drug users. HCV genotyping was performed on PCR HCV RNA-positive samples using a commercial line probe assay (LiPA; Innogenetics, Ghent, Belgium). HCV genotype 4 is found to be the predominant genotype among HCV-infected Lebanese patients (ranging from 34.2% to 53.3%) followed by 1a (ranging from 12.5% to 43.3%) and 1b (ranging from 8.0% to 34.4%). In patients with symptomatic liver disease, however, genotype 4 (34.2%) was preceded by genotype 1a (39.5%). The predominance of HCV genotype 4 in our population (45.7%) confirms the predominance of HCV genotype 4 in Lebanon and most of the Arab countries in the Middle East but contrasts with data reported from non-Arab Middle Eastern Countries as can be seen from the literature review. Implications of genotyping for clinical outcome of HCV infection, response to treatment as well as for vaccine development are discussed.

Current prevalence of hepatitis delta virus (HDV) infection and the range of HDV genotypes in Lebanon.

Recently the prevalence of hepatitis B virus (HBV) genotypes and the association between these genotypes and the clinical status of HBV-infected patients were recently investigated in the Lebanese population. The aim of the additional study reported here was to determine the current prevalence of hepatitis delta virus (HDV) infection and the range of HDV genotypes in this Lebanese population. Two hundred and fifty-eight HBsAg-positive patients (107 asymptomatic blood donors, 92 with chronic hepatitis, 24 with cirrhosis, 15 with hepatocellular carcinoma, 20 patients on haemodialysis) from ten medical centers in Lebanon were tested for antibody to hepatitis D virus (anti-HDV). Those testing positive were analysed further for HDV-RNA and for genotyping by reverse transcriptase-polymerase chain reaction (RT-PCR) and restriction fragment length polymorphism (RFLP). Three samples (1.2%) were anti-HDV positive and out of these, only one was HDV-RNA positive (0.6%) and was analysed as HDV genotype I. Our results point to a low endemicity of HDV in the Lebanese population which is in sharp contrast to data reported from Lebanon 20 years ago and to the situation in neighbouring Arab and non-Arab countries in the Mediterranean region. HDV genotype I seems to be the predominant genotype in Lebanon and the Middle East.

Frequency and significance of antibodies against hepatitis B core (anti-HBc) antigen as the only serological marker for hepatitis B infection in Lebanese blood donors.

During a 2-year period, blood samples from 2505 Lebanese blood donors were chosen at random, at various periods of time at one blood donation centre (Hotel Dieu de France, Beirut, Lebanon) and were screened for markers of HBV infection (HBsAg, anti-HBc and anti-HBs). The study showed HBsAg positivity of 0.6% and an overall exposure rate to HBV of 10.0%. Out of the 2505 blood donors screened, 56 (22%) were found to be 'anti-HBc alone' positive which is almost four times the HBsAg positivity. The 56 'anti-HBc alone' samples were retested by another ELISA kit commercially available and 54 samples were 'anti-HBc alone' positive by both assays. The 54 samples had no serological markers as evidence of infection with human immunodeficiency virus (HIV) or hepatitis C virus (HCV). Only seven (13%) out of the 54 samples were HBV DNA positive by PCR and all were HBV genotype D. All seven HBV DNA-positive samples had HBV DNA levels below 400 copies/ml. Although any circulating HBV DNA among our 'anti-HBc alone' blood donors was below the detection limit of our Amplicor Monitor assay, some of these samples had circulating virus. A national study, where a larger number of blood donors from different blood donation centres across the country will perhaps determine whether screening for anti-HBc in addition to HBsAg detection is needed in Lebanese blood donors.

Hepatitis C virus infection in Lebanese patients with B-cell non-Hodgkin's lymphoma.

Several studies from many countries have reported a high prevalence (> 9%) of hepatitis C virus (HCV) infection in patients with B-cell non-Hodgkin lymphoma (B-NHL) suggesting a possible etiological role of HCV in the development of B-NHL. Data from the United Kingdom and Turkey, however, did not confirm these observations. To determine the prevalence of HCV infection in patients with B-cell lymphoma in Lebanon, a controlled study was conducted in which 318 Lebanese patients were investigated. These included 35 patients with B-NHL, 63 patients with various malignant conditions (control group 1) and 220 patients with non-malignant conditions (control group 2). Samples were tested in duplicates for antibodies to HCV (anti-HCV) by enzyme-linked immunosorbant assay (ELISA). None of the 318 patients investigated were anti-HCV positive. Based on our findings, it can be concluded, that, there is no sufficient evidence to indicate that HCV plays role in the development of B-NHL in Lebanese patients. Predisposing factors in lymphoproliferative disorders are numerous including both genetic and environmental factors that could vary from one geographic region to another.

Comparative analysis between Pseudomonas aeruginosa genotypes and severity of symptoms in patients with unilateral or bilateral otitis externa.

Random amplified polymorphic DNA (RAPD) analysis was done on 32 isolates of Pseudomonas aeruginosa. These isolates were obtained from 22 patients who presented to the emergency room in a major medical center in Beirut, Lebanon, during a 5-month period with the diagnosis of either unilateral or bilateral otitis externa. Patients had yellowish to greenish discharge, moderate to severe external auditory canal swelling, moderate to severe pain, and periauricular cellulitis. None of these patients had intrinsic predisposing factors. An ear swab was obtained from both ears of patients, cultured on trypticase soy agar. P. aeruginosa was identified on the basis of pyocyanine production and API identification kits. RAPD analysis was done by using two primers (10 mer and 21 mer primers) and appropriate PCR conditions on extracted DNA. Our data have shown 23 RAPD patterns (A-W) distributed among the 32 P. aeruginosa isolates. RAPD patterns were reproducible. Twenty of 32 isolates were recovered from 10 patients with bilateral otitis externa. The remaining 12 of 32 isolates were recovered from 12 different patients with unilateral otitis externa. Eleven RAPD patterns (A,B,C,D,E,F,H,I,R,U,V) were associated with severe clinical symptoms, including severe pain, severe external auditory canal swelling, periauricular cellulitis, and a yellowish discharge. The remaining RAPD patterns were not associated with severe infections. This denotes a possible association between certain genotypes and severity of symptoms.