Significance of Adopting Nucleic Acid Amplification Technique for Blood Donor Screening in a Resource Limited Setting: A Study from a Single Centre in South India.

Nucleic acid Amplification testing (NAT) has helped improve blood safety and detect window period and Occult Hepatitis B infections (OBI) This study was aimed at determining the following in blood donors: 1. seroprevalence of HIV, HBV & HCV, malarial parasite and Syphlis 2. NAT and seroyield for HIV, HBV and HCV 3. viral load in NAT yield donations 4. Pattern of HBV serological markers in HBV NAT yield donations 80,809 blood donations were screened over an 8 year period (2012-2019) for antiHIV I and II, HBsAg, antiHCV antibodies, malarial parasite and VDRL. Seronegative samples were tested by NAT using a multiplex PCR in a pool of six. NAT yield samples were tested for viral load and HBV serological markers. Seropositive samples were tested for NAT and checked for seroyield. SPSS windows version 24.0 was used for statistical analysis. 1.07% of blood donors were found to be seropositive with 0.08%, 0.86%, 0.09%, 0.03% and 0 for anti HIV I and II, HBsAg, antiHCV, VDRL and Malarial parasite respectively. Out of 79,938 seronegative samples, 20 samples (0.025%) were NAT positive for Hepatitis B with a NAT yield OF 1:3997. Out of the 20 NAT positive samples, 17 were OBI and three were window period infections. 14 NAT yield samples subjected to a HBV viral load assay showed a range of < 6-146 IU/ml. Minipool NAT in pools of six is able to indentify both OBI and window period infections. NAT could significantly improve the blood safety in a resource limited setting like India.

Convalescent plasma - Is it useful for treating SARS Co-V2 infection?

The world is challenged with the severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) pandemic. Although preventive measures such as social distancing, personal protective equipment and isolation would decrease the spread of the infection, a definitive treatment is still under way. Antivirals, immunisation, convalescent plasma (CP) and many more modalities are under trial, and there has been no definite answer to the management of COVID-19 infection. All patients so far have received the standard and symptomatic care. It is shown that the SARS-CoV 2 is a respiratory pathogen, and 80% of the infected patients would recover from the illness and it is the 20% of the infected patients require hospitalisation and even critical care. CP has been used to treat recent epidemic respiratory infections such as Middle East respiratory syndrome and severe acute respiratory syndrome (SARS) infections with promising results. The CP of a recovered individual contains antibodies which neutralise the virus and decrease the viral replication in the patient. It is a classic adaptive immunotherapy and has been applied in the prevention and treatment of many infectious diseases. CP is plasma taken from a person who has recovered from an infection, which contains neutralising antibodies against the said infection. Giving CP to susceptible individuals or infected patients is a form of passive antibody therapy and in the case of SARS-CoV-2, is expected to provide protection by viral neutralisation and antibody-dependent cytotoxicity and phagocytosis. The adaptive response is to a specific antigen-binding array of molecules that are foreign to the host. The human response to viruses uses both the innate and the adaptive arms in its attempt to rid the host of the invading pathogen. The humoral response is a component of the adaptive immune response that allows for antibodies to bind to foreign invading pathogens, marks the pathogens and their toxins for phagocytosis and recruits further phagocytic cells to the site via the activation of the complement system and eventually prevents the pathogen from infecting target cells. Studies from Wuhan from various institutions during the research on COVID-19 infections during December 2019 have also shown promising results. Till date, randomised controlled studies for the use of CP in SARS-CoV-2 infection are lacking, and many countries have invited institutions to participate in clinical trials. The Indian Council of Medical research and the Central Drugs Standard Control Organisation, Government of India, have allowed the use of CP as an investigational drug under a trial basis. Internationally, agencies such as the USFDA, American Association of Blood Banks, European Blood Safety and British Blood Transfusion Society have also come out with various guidelines for the use of CP in COVID-19 infection. This article will review the current guidelines for the use of CP and compare the various guidelines of different agencies.

Emergency therapeutic leukapheresis in a case of acute myeloid leukemia M5.

Cell separators in India are routinely used for plateletpheresis, peripheral blood stem cell collections and therapeutic plasma exchange. Therapeutic leukapheresis, particularly as an emergency procedure, has been uncommonly performed and reported. Here, a case of a 53-year-old male, diagnosed with acute myeloid leukemia subtype M5 (AML M5) with hyperleukocytosis, who underwent emergency leukaphereis, is reported. After two procedures, there was a decrease of WBC count by 85%, which enabled cytotoxic therapy to be initiated.

Comparison of plateletpheresis on the Fresenius AS.TEC 204 and Haemonetics MCS 3p.

This is an attempt at comparing two cell separators for plateletpheresis, namely the Fresenius AS.TEC 204 and Haemonetics MCS 3p, at a tertiary care center in India. Donors who weighed between 55-75 kg, who had a hematocrit of 41-43%, and platelet counts of 250x10(3)-400x10(3)/microl were selected for the study. The comparability of the donors who donated on the two cell separators were analysed by t-test independent samples and no significant differences were found (P>0.05). The features compared were time taken for the procedure, volume processed on the separators, adverse reactions of the donors, quality control of the product, separation efficiency of the separators, platelet loss in the donors after the procedure, and the predictor versus the actual yield of platelets given by the cell separator. The volume processed to get a target yield of >3x10(11) was equal to 2.8-3.2 l and equal in both the cell separators. Symptoms of citrate toxicity were seen in 4 and 2.5% of donors who donated on the MCS 3p and the AS.TEC 204, respectively, and 3 and 1% of donors, respectively, had vasovagal reactions. All the platelet products collected had a platelet count of >3x10(11); 90% of the platelet products collected on the AS.TEC 204 attained the predicted yield that was set on the cell separator where as 75% of the platelet products collected on the MCS 3p attained the target yield. Quality control of the platelets collected on both the cell separators complied with the standards except that 3% of the platelets collected on the MCS 3p had a visible red cell contamination. The separation efficiency of the MCS 3p was higher, 50-52% as compared to the 40-45% on the AS.TEC 204. A provision of double venous access, less adverse reactions, negligible RBC contamination with a better predictor yield of platelets makes the AS.TEC 204 a safer and more reliable alternative than the widely used Haemonetics MCS 3p.