A new variant of GB virus C/hepatitis G virus (GBV-C/HGV) from South Africa.

Phylogenetic analysis of the 5' non-coding region (5'NCR) sequences has demonstrated that GB virus C/hepatitis G virus (GBV-C/HGV) can be separated into three major groups that correlate with the geographic origin of the isolate. Sequence analysis of the 5'NCR of 54 GBV-C/HGV isolates from 31 blood donors, 11 haemodialysis patients and 12 patients with chronic liver disease suggests the presence of a new variant of GBV-C/HGV in the province of KwaZulu Natal, South Africa. Eleven isolates grouped as group 1 variants (bootstrap support, 90%) found predominantly in West and Central Africa, a further six isolates grouped as group 2 variants (bootstrap support, 58%) found in Europe and North America; five of which grouped as 2a (bootstrap support, 91%) and one as 2b (bootstrap support, 87%), the latter also includes isolates from Japan, East Africa and Pakistan. Although the remaining 37 GBV-C/HGV isolates were more closely related to group 1 variants (bootstrap support, 90%), they formed a cluster, which was distinct from all other known GBV-C/HGV sequences. None of the South African isolates grouped with group 3 variants described from Southeast Asia. Three variants of GBV-C/HGV exist in KwaZulu Natal: groups 1, 2 and a new variant, which is distinct from other African isolates.

GB virus C/hepatitis G virus infection in KwaZulu Natal, South Africa.

Sera from 70 patients on maintenance haemodialysis, 98 patients with chronic liver disease, and 232 volunteer blood donors in the province of KwaZulu Natal, South Africa, were screened for GB virus/hepatitis G virus (GBV-C/HGV) RNA and anti-E2 by reverse transcription-polymerase chain reaction (RT-PCR) and by an enzyme-linked immunosorbent assay (ELISA), respectively. GBV-C/HGV RNA was detected in 17/70 (24.3%) haemodialysis patients, 12/98 (12.2%) patients with chronic liver disease, and 44/232 (18.9%) blood donors (Africans [29/76; 38.2%]; Asians [2/52; 3.8%]; Whites [11/49; 22.4%], and "Coloureds" [persons of mixed origin; 2/55; 3.6%]). Overall (anti-E2 and/or RNA) 43.9% (43/98) of patients with chronic liver disease, 47.1% (33/70) of haemodialysis patients, and 31.9% (74/232) of blood donors (Africans [44/76; 5.9%]; Asians [5/52; 9.6%]; Whites [15/49; 30.6%], and Coloureds [9/54; 16.6%]) were exposed to GBV-C/HGV infection. There was a significant difference in the prevalence of GBV-C/HGV infection (RNA and/or anti-E2) between African blood donors and the other racial groups (P < .001), and between blood donors and haemodialysis patients (P = .02) and patients with chronic liver disease (P = .04). Anti-E2 antibodies and GBV-C/HGV RNA were almost mutually exclusive. GBV-C/HGV-infected haemodialysis patients received more transfusions (P = .03) than noninfected patients. There was no significant difference in liver biochemistry between GBV-C/HGV-infected and noninfected patients and between blood donors in each of the four racial groups. The high prevalence of GBV-C/HGV infection in blood donors and chronic liver disease patients, and the lack of elevated liver enzymes and clinical hepatitis in blood donors and haemodialysis patients, suggest that GBV-C/HGV may not be associated with liver disease.

Biodistribution, stability, and antiviral efficacy of liposome-entrapped phosphorothioate antisense oligodeoxynucleotides in ducks for the treatment of chronic duck hepatitis B virus infection.

This study investigated the feasibility of using liposomes to increase the hepatic delivery and antiviral efficacy of phosphorothioate antisense oligodeoxynucleotides (PS-ODN) for the in vivo treatment of hepatitis B virus (HBV) infection. Ducks infected with duck hepatitis B virus (DHBV) were used as the model. We studied the stability of an antisense PS-ODN in duck plasma, its integrity during the process of liposome entrapment, its in vivo biodistribution, plasma clearance, and excretion. In addition, the intrahepatic distribution of a labeled free and liposome-entrapped ODN was also investigated. The results of our studies show that: 1) phosphorothioate ODN remain stable during the process of liposome entrapment; 2) are stable in duck plasma for many hours; 3) are rapidly cleared from the plasma when injected intravenously; 4) intravenous injection of antisense ODNs entrapped within liposomes enhances delivery of the ODN to the liver; and 5) inhibit DHBV replication. Serum DHBV DNA levels fell rapidly, with a corresponding decrease in intrahepatic viral replicative intermediates at the end of the 5-day study period. Although inhibition of viral replication and a fall in the target protein was observed, a marked inhibition of viral replication was also observed with high doses of a random-sequence ODN. Thus, it is not certain that inhibition of viral replication was entirely through an antisense mechanism. Therefore, liposomes may be effective vehicles to improve the delivery of antisense oligonucleotides to the liver for the therapy of hepatotropic viruses.

Lymphocyte and macrophage phenotypes in chronic hepatitis C infection. Correlation with disease activity.

The pathogenesis of chronic hepatitis C and the mechanisms underlying progressive liver disease in patients with chronic hepatitis C infection are poorly understood. To demonstrate which inflammatory cells might be responsible for the necroinflammatory damage in chronic hepatitis C infection, we have correlated the phenotype of the intrahepatic lymphocytes and macrophages with histological activity in liver biopsy and explant specimens from 19 patients with chronic hepatitis C infection. In all stages of disease, more CD8+ than CD4+ lymphocytes were found. However, histologically active versus histologically mild hepatitis was associated with a trend toward greater parenchymal concentrations of CD4+ lymphocytes (0.71 +/- 0.27 per 10(4) microns 2 versus 0.35 +/- 0.15; not significant), significantly less parenchymal CD8+ lymphocytes (0.90 +/- 0.1 versus 1.70 +/- 0.3; t = 2.32, P = 0.03) and a greater parenchymal CD4/CD8 ratio (4.1 +/- 2.8 versus 0.91 +/- 0.3; t = 1.65, P = 0.07). No difference was found in the number of cells containing cytotoxic granules between the two groups. Greater numbers of CD4+ lymphocytes were found in liver biopsy specimens with little or no staining for hepatitis C virus antigen (1.47 +/- 0.88 versus 0.27 +/- 0.27; t = 2.28, P < 0.05). No significant differences were found in the macrophage subsets between the three stages of disease. Our data suggest that active histological disease in chronic hepatitis C infection may be associated with an increase in CD4+ lymphocytes and suggest that CD4+ T cells may play an important role in the hepatic injury in these patients.

A clinical evaluation of a new method for HBV DNA quantitation in patients with chronic hepatitis B.

Selection of HBsAg-positive patients for antiviral therapy requires an estimation of disease activity and viral replication. Serum transaminases and histological analysis are commonly used to assess disease activity, and viral replication is assessed by serological testing of HBeAg and serum hepatitis B virus (HBV) DNA. Dot blot hybridisation may be insufficiently sensitive to corroborate low-grade replication in patients with active hepatitis, and polymerase chain reaction (PCR) may be testing too sensitive for this role. Theoretically an assay of intermediate sensitivity is therefore required. Our aim was to evaluate whether the branched chain DNA (bDNA) assay would fulfil this function. Seventy-one HBsAg-positive patients were tested for HBV DNA by the bDNA assay; 64 were also tested by dot blot hybridisation and, when appropriate, also by PCR. Thirty-seven (52%) patients were positive for HBV DNA by the bDNA assay. HBV DNA was detected in the majority (21/28; 75%) of HBeAg-positive patients but also in 14 of 36 (39%) anti-HBe-positive patients. HBV DNA was detected by the bDNA assay in 20 of 48 (42%) patients negative for HBV DNA by dot blot hybridisation assay. All patients positive for HBV DNA by dot blot hybridisation were also positive by the bDNA assay. Sixteen of twenty-five (64%) patients negative for HBV DNA by the bDNA assay were positive for HBV DNA by PCR. The bDNA assay is a sensitive and reliable method for the detection of HBV DNA. As nucleoside analogue therapy becomes more widely available, the assay should provide a useful tool for the selection for and monitoring of patients on antiviral therapy.

Etiology, screening, and treatment of hepatocellular carcinoma.

The prognosis with large hepatocellular carcinomas is poor, and only palliative treatment is available. Small tumors are amenable to several modes of treatment, including liver transplantation, resection, or alcohol injection, with acceptable 5-year survival rates. Although the value of screening for hepatocellular carcinoma has yet to be shown, these data, coupled with the recognition of at-risk groups and useful diagnostic techniques, might encourage the clinician to screen at-risk patients in the clinic. New imaging techniques such as ultrasonographic angiography enhanced with CO2 microbubbles, or color Doppler ultrasound, may clarify the intratumoral blood flow of small tumors.

Severe and complicated malaria in KwaZulu-Natal.

OBJECTIVE: To describe severe and complicated malaria, including the common complications, causes of death and predictors of poor outcome. DESIGN: Retrospective case series. SETTING: King Edward VIII Hospital, Durban, Natal, a referral centre. PATIENTS: One hundred and forty-three consecutive patients (88 males, 55 females; median age 25 years, range 2-86 years) admitted with a microscopic diagnosis of Plasmodium falciparum malaria from 1984 to 1991. MAIN OUTCOME MEASURES: A univariate analysis comparing survival and death for categorical and continuous data for various complications was performed using the t-test or chi 2-test (or Fisher's exact test in the case of small cell sizes). Variables that showed significance on univariate analysis (P < 0.1) were used in a multivariate analysis to determine which contributed independently to survival or death. RESULTS: The case fatality rate was 11.1% (15/135) and the commonest complications were hyperparasitaemia (30%), renal failure (17%), acidaemia (14%), jaundice (10.4%) and cerebral malaria (6%). The commonest complications in patients who died were renal failure (10 patients), cerebral malaria (7), hyperparasitaemia (6) and severe anaemia (5). Multivariate analysis using a logistic regression model showed a high parasite load and cerebral malaria (relative risks of 11.9 and 51.8 respectively) and high urea levels to be the significant predictors of poor outcome (95% confidence intervals 1.53-91.9, 2.74-100.0 and 1.01-1.09, respectively). CONCLUSIONS: Patients with high parasite densities, cerebral involvement and renal dysfunction need urgent attention with parenteral chemotherapy, intravenous fluid replacement and early referral to a tertiary hospital with facilities for intensive monitoring and supportive treatment.

Hepatitis C virus infection in chronic liver disease in Natal.

The aim of this cross-sectional seroprevalence study was to determine the prevalence of antibodies to hepatitis C virus (HCV) (anti-HCV) in patients with cirrhosis, hepatocellular carcinoma (HCC) and chronic active hepatitis (CAH) attending a referral hospital in a hepatitis B virus (HBV)-endemic area in South Africa. One hundred and ten patients with suspected cirrhosis, 44 with suspected HCC and 6 with chronic hepatitis were initially included. The diagnoses were confirmed in 77 patients with cirrhosis (histologically or macroscopically at peritoneoscopy), 33 patients with HCC (histologically or elevated alpha-fetoprotein levels plus focal lesion on hepatic imaging) and 6 patients with CAH (histologically) without antinuclear antibodies. All patients were tested for anti-HCV with the Abbott second-generation enzyme immunoassay combined with a supplemental neutralisation assay, and hepatitis B surface antigen (HBsAg). Anti-HCV seroprevalence for cirrhosis, HCC and CAH were 18/77 (23%), 8/33 (24%) and 2/6 (33%) respectively. HBsAg was detected in serum in 16 (21%), 15 (46%) and 1 (17%) patient respectively. Only 1 patient (with cirrhosis) was positive for both anti-HCV and HBsAg. Of those who were anti-HCV-positive, 4/18 (22.2%) cirrhotics, none with HCC and 1/2 (50%) with CAH, had previously received blood transfusions, resulting in a cumulative frequency of 5/28 (18%). Our results indicate that HCV is an important aetiological agent in the pathogenesis of chronic liver disease in our patients. In the majority of patients (82%), the infection was not transfusion-related. Thus, screening of blood donors for anti-HCV would not prevent the majority of cases of chronic liver disease secondary to HCV. It appears as if HCV and HBV have different modes of transmission in southern Africa.

Ascitic fluid gamma interferon concentrations and adenosine deaminase activity in tuberculous peritonitis.

The gamma interferon (gamma-IFN) concentration and the adenosine deaminase (ADA) activity were evaluated in 30 patients with tuberculous peritonitis, 21 patients with ascites due to a malignant disorder, and 41 patients with cirrhosis. The gamma-IFN concentrations were significantly higher (p < 0.0001) in tuberculous peritonitis patients (mean: 6.70 U/ml) than in the malignant (mean: 3.10 U/ml) and cirrhotic (mean: 3.08 U/ml) groups. Use of a cut off value of > or = 3.2 U/ml gave the assay a sensitivity of 93% (25 of 27), a specificity of 98% (54 of 55), positive (P+) and negative (P-) predictive values of 96% and a test accuracy of 96%. The ADA activity was significantly (p < 0.0001) higher in the tuberculous peritonitis group (mean: 101.84 U/l) than in the control groups (cirrhosis (mean: 13.49 U/l) and malignancy (mean: 19.35 U/l)). A cut off value of > 30 U/l gave the ADA test a sensitivity of 93% (26 of 28) a specificity of 96% (51 of 53), a (P+) value of 93%, a (P-) value of 96%, and a test accuracy of 95%. There was a significant (p < 0.0001) correlation (r = 0.72) between ADA activity and gamma-IFN values in patients with tuberculous peritonitis. These results show that a high concentration of gamma-IFN in ascitic fluid is as valuable as the ADA activity in the diagnosis of tuberculous peritonitis. Both are rapid non-invasive diagnostic tests for tuberculous peritonitis.

Racial differences in the seroprevalence of hepatitis A virus infection in Natal/KwaZulu, South Africa.

The age- and race-specific seroprevalence of hepatitis A virus (HAV) infection was determined by radioimmunoassay (RIA) in 786 subjects between the ages of 6 months to 60 years. More than 50% of African children were seropositive by the age of 5 years. In blood donors (17-60 years), 50% (93/187) of Whites, 67% (110/163) of Indians, 85% (117/137) of Coloureds, and 91% (115/127) of Africans were seropositive. There was a significant difference in the seroprevalence of HAV infection between White blood donors and blood donors from the other three racial groups [Coloureds (P < 0.0001), Africans (P < 0.0001), and Indians (P < 0.001)] and between Indians and Coloureds (P < 0.0001) and Indians and Africans (P < 0.0001). There was no significance difference in HAV infection between Coloureds and Africans (P < 0.200). Eighty-seven per cent (32/37) of rural Africans had previous infection. In the African population HAV infection is acquired in childhood. There are significant racial differences in the seroprevalence of HAV infection. The surveillance of HAV infection may be used as a valuable yardstick to monitor the changing standards of hygiene and socioeconomic conditions of a community in transition in South Africa and to make rational public health decisions regarding a hepatitis A vaccination policy.

Hepatic abscess caused by Salmonella typhi. A case report and review of the literature.

Salmonella typhi is a rare cause of liver abscess. We describe a 47-year-old African male with multiple liver abscesses due to S. typhi in an area where hepatic amebiasis is endemic. The patient did not respond appropriately to amebicidal therapy and culture of the liver aspirate on two occasions yielded S. typhi. The Widal test, initially negative, became positive on repeat testing 10 days later. Percutaneous aspiration combined with appropriate antibiotic therapy resulted in a complete recovery. No predisposing cause could be found. We report the clinical, radiological, and microbiological features of this case and review the literature on this rare but easily treatable condition.

Are anticardiolipin antibodies responsible for some of the complications of severe acute Plasmodium falciparum malaria?

What were first called simply false-positive Wassermann reactions and then lupus anticoagulant are now known as antiphospholipid or anticardiolipin antibodies (ACA). These are known to cause a tendency to thrombosis and are frequently present in many neurological conditions and infections. The pathological significance of these antibodies in acute infections, if any, is unknown. We investigated the presence of these antibodies in Plasmodium falciparum malaria in an endemic area in Natal/KwaZulu, and attempted to correlate the presence of this antibody with cerebral manifestations. Immunoglobulin G-anticardiolipin antibodies measured by enzyme-linked immunosorbent assay occurred significantly more frequently in 62 patients with acute Plasmodium falciparum malaria (33.9%) than in 37 control subjects (2.7%) (P < 0.0001). There was no significant difference in the mean parasite loads in those patients who were positive for ACA (1.75%) and those who were negative (1.59%) (P = 0.83). No correlation was found between parasite load and ACA levels in the patient group, or between the number of cerebral manifestations in patients with and without the antibody. The frequency of splenomegaly was not significantly different in patients with and without ACA (P = 0.06). We conclude that there is a high prevalence of ACA in acute falciparum malaria. The pathological significance of this antibody and its relationship to complications, especially cerebral ones, warrant greater attention and may improve the understanding of cerebral malaria and its management.

Hypercalcaemia and multiple osteolytic lesions in childhood acute lymphoblastic leukaemia.

A 12 year old boy presenting with hypercalcaemia (calcium 3.25 mmol/l) and osteopaenia with multiple osteolytic lesions was found to have acute lymphoblastic leukaemia without lymph-adenopathy or organomegaly. Hypercalcaemia is a rare feature of acute leukaemia, but the patients previously described all show very similar characteristics, which were highlighted in this patient. These include age (10-20 years), severe osteolytic bone lesions, lymphoblastic leukaemia, and normal white cell count with absent or rare circulating blasts. Parathyroid hormone levels were normal in this patient, and response to induction therapy was good. This case demonstrates that acute lymphoblastic leukaemia may present in an atypical form without peripheral blasts but with hypercalcaemia and gross skeletal changes.

Hepatitis C virus antibodies among risk groups in a South African area endemic for hepatitis B virus.

The prevalence of anti-HCV was studied in a South African area endemic for hepatitis B virus. A total of 35,685 volunteer blood donors (22,034 whites, 9,218 Asians, 3,077 Africans, 1,356 coloureds), 71 haemophiliacs, 84 chronic dialysis patients, 100 antenatal attenders, 212 nurses, and 20 HIV-positive male homosexuals were tested for anti-HCV. Repeat positive second generation Ortho HCV EIA was used to determine HCV status for the blood donors; Abbott-II HCV EIA combined with a neutralisation test was used for the other risk groups. Antibody to hepatitis B core antigen (anti-HBc) was also tested in the haemophiliacs, nurses, and chronic dialysis patients. Seroprevalence for the blood donor population was 0.16, 0.34, 0.75, and 0.22% for whites, Asians, Africans, and coloureds, respectively. Of the risk groups tested, 39.4% of haemophiliacs and 4.8% of chronic dialysis patients were positive; of the remainder tested none was positive. Fifty percent of nurses, 47.9% of haemophiliacs, and 22.6% of dialysis patients had serological evidence of past exposure to hepatitis B virus (anti-HBc positive). These findings indicate a low prevalence of anti-HCV in the blood donor population, thus probably resulting in a low prevalence in groups exposed to blood and blood derivatives. The overall difference in prevalence between the race groups was significant (P < 0.0001). The high prevalence of hepatitis B virus compared to the low prevalence of HCV suggests that the main modes of transmission of the two viruses are probably different.