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Four cases of type 2 hepatitis B virus (HBV-2) infection were demonstrated in the Gizan area of Saudi Arabia during the hepatitis B marker ELISA screening of the 152 native pregnant females, 42 cases of primary hepatocellular carcinoma, 19 cases with an epithelial but non-hepatic malignancy, 16 with a non-epithelial and non-hepatic malignancy and eight with chronic hepatitis. HBV-2 infection diagnosis was based on HBsAg positivity without anti-HBc, anti-HBs and HBeAg in one pregnant female and one patient each with a primary hepatocellular carcinoma, lymphocytic lymphoma and metastatic adenocarcinoma. During neutralisation of HBsAg ELISA reactivity, the respective reduction in absorbance values in sera from the pregnant female and the patient with primary hepatocellular carcinoma were 21% and 76% respectively. HBV-2 specific gene probes would be needed to define its role in pathogenesis of malignant neoplasms and chronic hepatitis. Incorporation of pre-S2 sequences in future hepatitis B vaccines is likely to protect against both, HBV-2 and conventional hepatitis B (HBV-1) exposures.

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Ali et al 1 describe their experience with cases of malignant lymphomas seen at the King Faisal Specialist Hospital and Research Centre, Riyadh. Staining by the avidin-biotin complex technique on unfixed fresh tissues obtained from patients with non-Hodgkin's lymphomas was done using a panel of different T-and B-lymphocyte surface antigens. 1 This has revealed that, of the 211 large cell lymphomas discovered in Saudi adults, 37.3% were T-cell type. Categorization of lymphocytes into the two types was not feasible in unidentified lymphomas from Saudi patients because the biopsies had been performed elsewhere and unfixed tissues for snap-freezing were not available. 1 Nevertheless, an immunological classification of lymphocytes in lymphoid tissue fixed in formalin and embedded in paraffin could always be attempted with the avidin-biotin complex staining using the monoclonal antibody preparation L26. This preparation is an unclustered pan-B cell reagent and identifies all B cells, even in routinely fixed and embedded tissues. Except for B cells in cases of acute lymphoblastic leukemia, L26 is a specific marker for B-cell differentiation in non-Hodgkin's lymphomas. It also has a sensitivity and specificity comparable to other B-cell-related marker reagents.Staining with L26 on 40 B-cell lymphomas was uniformly strong in 37 cases except for two cases of malignant plasmocytic lymphoma and one case of common acute lymphoblastic leukemia. Moreover, staining of 18 T-cell lymphomas with L26 was not successful except in one instance. 2 L26 for use in staining malignant lymphomas would be desirable to assess the national frequency of T-and B-cell lymphomas in Saudi Arabia. Its application would ensure that the reported mean, 37.3%, 1 and the 95% confidence interval of 30.8 to 43.8% observed for T-cell lymphomas in the Riyadh population were representative of their overall incidence in Saudi Arabia.No details are available regarding re-confirmation of the initial positivity for HTLV-1 antibody in seven of the 130 patients with malignant lymphomas. 1 False-positive results from the retrovirus antibody screen in antiglobulinbased enzyme linked immunosorbent assay (ELISA) tests have led to insurmountable problems. The possibility of a false-positive has to be eliminated by repeated testing using a different ELISA test system, as well as by confirming all repeated ELISA positives with an immunoblot test (Western blot) or radioimmunoprecipitation (RIPA) testing. In a recent multicenter HTLV-1 antibody screening program carried out in Australia on 9642 prospective blood donors, only 20 donors were repeatedly reactive using an Abbott or Dupont ELISA test system. 3 Of the 20 samples in which the Dupont test was used, 18 were nonreactive in the Abbott test system, 17 produced an indeterminate Western blot pattern, and one was negative on the Western blot. The two samples that were reactive in both of the ELISA tests produced an indeterminate result on the Western blot. Definite evidence of anti-p24 reactivity was observed only in two...