Prevalence & significance of hepatitis C virus (HCV) seropositivity in blood donors.

BACKGROUND & OBJECTIVES: The clinical significance of anti HCV antibodies in healthy blood donors remains uncertain. These donors are usually asymptomatic and it is difficult to elicit risk factors of acquiring HCV infection during pre-donation questioning. Limited information on donor recall and follow up studies on anti HCV positive blood donors have been reported from India. Paucity of data which is likely to have an impact on safe blood transfusion programme has prompted us to undertake this study to assess the significance of HCV seropositivity in blood donors with respect to their clinical, biochemical and virological profile. METHODS: A total of 16,250 blood units were screened for the mandatory tests using third generation ELISA (anti HIV 1&2, anti HCV, HBsAg), VDRL and peripheral smear for malaria. Donors reactive for anti HCV were informed. Repeat anti HCV reactive donors were subjected to detailed clinical history focusing on risk factors for HCV transmission. The blood tests included liver function tests (LFT), coagulation and autoimmune profile, qualitative serum cryoglobulins and HCV RNA detection. These donors were followed at 2-3 monthly intervals for a minimum period of six months by LFT. RESULTS: An overall seropositivity of 0.44 per cent (72/16,250) was observed in our donors which was significantly lower in first time, young voluntary donors as compared to replacement donors (0.27 vs. 0.60%). In contrast to drug abuse (6.4%) we found minor percutaneous routes like sharing of shaving kits or visit to a road side barber (32%) as the major risk factor for HCV transmission. There was no prior history of blood transfusion in any of these donors; however history of some surgical procedures was present in 25.8 per cent. Raised transaminases and HCV viraemia were observed in 87 and 71 per cent donors respectively. An association was observed between HCV RNA when the ELISA ratio was >5. INTERPRETATION & CONCLUSION: Voluntary donors form a safe source of blood supply and efforts should be made to increase this precious source to 100 per cent. Abbreviated behavioural donor screening questionnaire for repeat donors is not advisable. Awareness and education of donors is required regarding modes of HCV transmission. HCV positive donors should be informed about their disease, counselled and referred to hepatologist, and permanently deferred for future donations.

Platelet alloimmunization in multitransfused patients with haemato-oncological disorders.

BACKGROUND: We studied the incidence of platelet alloimmunization in multitransfused patients with haemato-oncological disorders and determined the factors influencing alloimmunization. We also assessed the effect of alloimmunization on response to platelet transfusion. METHODS: Fifty patients with haemato-oncological disorders who received multiple transfusions were included. The patients were tested for antibodies before they received any transfusion and then after 3-4 weeks of transfusion. Lymphocytotoxicity and platelet immunofluorescence suspension tests were used to detect antiplatelet antibodies. Symptomatic improvement was used to assess the response to platelet transfusions. RESULTS: Thirty patients were positive by the lymphocytotoxicity test, giving an incidence of 60% for anti-HLA antibodies. The panel reactivity of the antibodies ranged from 3% to 100%. Nineteen patients were positive by the platelet immunofluorescence suspension test, 16 of whom were also positive by the lymphocytotoxicity test. The overall incidence of antiplatelet antibodies was 66%. The number of transfusions received and the underlying haemato-oncological disorder were not risk factors for the development of antibodies. Patients with a past history of transfusions and those with a positive obstetric history had a significantly higher incidence of antibodies. The response to transfusion therapy was poor in patients with antibodies, as 71.4% of patients with antibodies were nonresponsive compared to only 26.6% of antibody-negative patients. CONCLUSION: A high percentage of multitransfused patients developed antiplatelet antibodies. Previous sensitization was an important risk factor for the development of antibodies. Patients with high panel reactivity (HLA) showed non-responsiveness to platelet transfusions. Testing for the presence of antiplatelet antibodies and provision of compatible platelets should be important components in the management of patients with platelet transfusion refractoriness.

Prevalence of markers of transfusion transmissible diseases in voluntary and replacement blood donors.

BACKGROUND: Transfusion of safe blood requires a safe donor. The voluntary donor movement encompasses the concept of a donor who is free from transfusion transmissible infections. It is now mandatory to screen blood for hepatitis B surface antigen, antibodies to HIV-1 and HIV-2, antibodies to hepatitis C virus, syphilis and malarial parasites. METHODS: Between 1996 and 2002, 235 461 donors were screened for markers of hepatitis B virus, and HIV-1 and HIV-2 using commercially available ELISA kits, VDRL test for syphilis and Geimsa stain for the malarial parasite, respectively. A total of 56 476 donors were screened for hepatitis C virus antibodies from June 2001 to December 2002, using third-generation ELISA kits. RESULTS: The proportion of voluntary donors increased from 47% to 56% during the study period. The prevalence of HIV showed a steady increase from 0.16% in 1996 to 0.3% in 2002. The prevalence of hepatitis B surface antigen decreased from 1.55% to 0.99%. VDRL reactivity did not show any trend and ranged between 0.11% and 0.66%. Hepatitis C virus antibodies showed a prevalence of 0.4%. The prevalence of all markers was significantly less in voluntary donors. Among the voluntary donors, transfusion transmissible disease markers were significantly less in student donors as compared to other donors. CONCLUSION: A change-over to a voluntary donor service would considerably reduce the number of infectious donors and, among voluntary donors, student donors are the safest.

Occult hepatitis B virus (HBV) infection in healthy blood donors.

Blood transfusion is an important route of transmission of hepatitis B virus (HBV). Occult HBV infection can exist in the absence of HBsAg and can be detected by determining HBV DNA. To determine the occult HBV infection in healthy blood donors. One hundred adult healthy blood donors, negative for HBsAg, anti HCV, HIV-1 and other risk factors were screened for HBV DNA by PCR. All the healthy blood donors were negative for HBV DNA by PCR. Occult HBV infection does not occur in the healthy blood donors in the population studied.

Evaluation of haemotherapy in thalassaemias (20 years of Indian experience).

Two hundred fifty-one patients of beta-thalassaemia ranging from 3 months to 15 years of age were evaluated. They were maintained on hypertransfusion regimen and received periodic transfusions of group specific packed red cells. These multiple transfused patients were subjected to the tests for detection of transfusion malaria, HBsAg and allo-antibodies against red cells. Malaria infection and HBsAg were detected in 6.4% and 15.5% of patients respectively, while allo-antibodies were detected in 15.5% of patients. Thirteen patients (5.18%) developed hypersplenism and associated pressure symptoms due to splenomegaly for which they underwent splenectomy. Postsplenectomy period was uneventful and showed marked decrease in the frequency and quantitative requirements of transfusions and overall improvement in health. The continuing steady improvement of the prognosis in thalassaemia secondary to hypertransfusion regimen required us to transfer attention to other problems involved in thalassaemia management such as problems of hypersplenism and problems of multiple transfusion.