Prashant Agarwal

Seroprevalence of Toxoplasma gondii antibodies in North Indian blood donors: Implications for transfusion transmissible toxoplasmosis

INTRODUCTION Transfusion transmitted Toxoplasma gondii (T. gondii) can result in significant clinical consequences in immunocompromised and multiply transfused patients, pregnant women and fetus etc. Anti-T. gondii seroprevalence, specifically IgM antibodies reflect the risk of transfusion transmission. METHODS Four hundred and ninety-three blood donors in a tertiary care hospital in North India were screened for IgG and IgM anti-T. gondii antibodies by enzyme linked immunosorbent assay (ELISA). RESULTS The prevalence of IgG and IgM anti-T. gondii antibodies was 51.8% and 5% respectively. The prevalence was higher in females (M=51.6%, F=89.2%) and in replacement donors (replacement donors=63.2%, voluntary donors=33.5%). CONCLUSION The donor population constitutes a significant risk of transfusion transmitted toxoplasmosis. Effective strategies are required to prevent transfusion transmitted toxoplasmosis.

Platelet utilization in the developing world: Strategies to optimize platelet transfusion practices

There is perennial shortage of blood and blood components in most of the developing world. The resources are inadequate in terms of meeting the ever growing demand of blood components especially platelets. A poor health care system has led to underdevelopment of blood transfusion services which ultimately affect the transfusion practices. There is a paucity of comprehensive data on the platelet usage from the developing countries which is reflective of their modest development in blood component therapy. This is in sharp contrast to the fast pace of development in platelet transfusion practice in developed world where platelet substitutes are to become a reality for clinical use in near future. In developing world a considerable heterogeneity exists for platelet transfusion practices between countries, and even within countries in hospitals where this precious resource is available. This variation in existing practices can partly be explained by factors like individual preferences, lack of any hospital transfusion policy with regard to platelet transfusion, problems of platelet availability, etc. There is a need to implement best platelet transfusion practices as platelet products are scarcely available and expensive. Few interventions are emphasized in this article in the context of improving the status of platelet utilization in developing countries.

Prestorage gamma irradiation induces oxidative injury to red cells.

BACKGROUND Gamma irradiation of blood results in the formation free radicals, which interact with lipids and proteins in the membranes of red blood cells. We have investigated oxidative injury to gamma-irradiated red cells by measuring markers of oxidative injury and its correlation with red cell membrane damage. METHODS Thirty red cell blood units were irradiated at 25 Gy using Gamma Irradiator (Nordion, Canada) and stored at 4°C for 28 days. Markers of oxidative injury such as MDA levels, methemoglobin formation and osmotic fragility and markers of membrane damage including supernatant Hb, supernatant K(+), and LDH were studied. RESULTS There was a progressive and statistically significant increase in markers of oxidative injury such as MDA (3.76 v/s 5.01), and methemoglobin formation (1.87 v/s 3.58) in irradiated red cells compared to control non-irradiated cells. Exposure to gamma irradiation caused significant increase in markers of hemolysis such as supernatant Hb (0.087 v/s 0.363), K(+) (35.1 v/s 51.2) and LDH (366.9 v/s 587.4) over the storage period of 28 days. CONCLUSION Gamma irradiation increases lipid peroxidation and oxidative injury to the red cells.

Evaluation of transfusion-related complications along with estimation of inhibitors in patients with hemophilia: A pilot study from a single center.

Background: Apart from inhibitor development in patients with hemophilia (PWH) the old problems of blood borne viral infections and red cell alloimmunization still persist in PWH from developing countries. This study was planned to detect the presence of inhibitors in our PWH and to determine the presence of transfusion transmitted infections (TTI) markers and clinically significant red cell alloantibodies in these patients. Materials and Methods: One hundred fourteen PWH were screened for various laboratory tests. Screening for inhibitors was done by mixing study. Blood grouping, TTI testing and red cell alloantibody detection were done as per the departmental standard operating procedures. Results: Out of 114 patients evaluated 98(86%) had hemophilia A and remaining 16(14%) had hemophilia B. Five (5.1%) patients of hemophilia A were positive on inhibitor screening. On Bethesda assay, one patient was high responder (14.4 BU/ml) and rest 4 were low responders (<5 BU/ml). Overall, 19 PWH were positive for TTI markers and two had clinically significant red cell alloantibody (anti-E and anti-Jkb). Conclusion: This is probably first comprehensive study from our state on laboratory testing in PWH. The specialty of Transfusion Medicine can be a core part of hemophilia care. The overall prevalence of inhibitors in our hemophilia A patients was 5.1%, which is less as compared to majority of published studies.

Automated platelet collection using the latest apheresis devices in an Indian setting

In a developing nation like India where there is a scarcity of resources and voluntary donors, provision of safe and good quality blood and its components is a huge challenge. The demand for platelets is increasing constantly due to better management of various patient categories, specifically hemato-oncological cases, where there is an increased demand of platelet transfusion. The use of apheresis single donor platelets (SDPs) has been attributed to increased gap between demand and supply of whole blood derived random donor platelets (RDPs). Moreover, the other benefits of SDPs such as decreased donor exposure and simplification of inventory management cannot be overlooked. However, the increased costs and logistic problems, compounded by the lack of awareness, limit the donor recruitment and procedures for SDPs. In Indian scenario, there are no specific guidelines or standards available which can be followed, while simultaneously addressing the associated problems. In this review, we have tried to analyze the various problems of donor selection, donor safety and the quality issues regarding plateletpheresis. Based on this we have tried to give certain recommendations which might help the centers in resolving the problems related to plateletpheresis.

Comprehensive analysis of changes in clinically significant divalent serum cation levels during automated plateletpheresis in healthy donors in a tertiary care center in North India

Background: Adverse effects due to apheresis are unusual. The most common apheresis-specific reaction is hypocalcemia due to citrate anticoagulation and induces ionized hypocalcemia and hypomagnesemia by chelating effect during the plateletpheresis; generally transient and self-limiting but has the potential of severely injuring donor. We have investigated total calcium (tCa ++ ) and magnesium (tMg ++ ) levels in sixty healthy plateletpheresis donors at different intervals during the procedure and 30 min post-procedure. Materials and Methods: A total of 60 procedures were performed on healthy donors. Blood samples were obtained from sterile diversion pouch placed on apheresis circuit. 5 ml sample in plain vials was obtained at different intervals during each procedure and 30 min after the end of the procedure. Samples were used for measurement of tCa ++ and tMg ++ levels. Results: There is continuous decrease in mean tCa ++ from baseline levels (9.83 ± 0.64 mg/dl) till end of procedure (8.33 ± 0.78 mg/dl), but after 30 min, levels again reached near their respective baseline values (9.42 ± 0.54 mg/dl). Similarly, mean tMg ++ fell from baseline levels (2.36 ± 0.3 mg/dl) till the end of procedure (1.39 ± 0.40 mg/dl). After 30 min, levels were again increased, their respective baseline values (2.25 ± 0.25 mg/dl). Conclusion: There is continuous, gradual, and significant fall (P < 0.05) in mean tCa ++ and mean tMg ++ from baseline levels to till the end of procedure but after 30 min of completion of procedure, levels again reached near their respective baseline values.

Quantification of feto-maternal hemorrhage: selection of techniques for a resource-poor setting.

Background: Though RhD sensitization in RhD-negative mothers is now almost eradicated in the developed world, it continues to be a major health problem in developing nations like India. Inadequate immunoprophylaxis is the main reason. Adequate dose calculation of anti-D Ig is possible through estimation of correct feto-maternal hemorrhage (FMH) volume. In this regard, different methods have been used. Methods: We evaluated three quantitative techniques of estimating FMH: the Kleihauer-Betke test (KBT) and two flow cytometry (FC) techniques, i.e., the indirect immunofluorescence technique (IIFT) and direct immunofluorescence technique (DIFT). Stock solutions of both RhD-positive and D-negative cells were made, and 7 serial dilutions of RhD-positive cord cells in D-negative adult cells were prepared. Result: Both KBT and FC approximated the expected concentration of fetal RhD-positive cells in all mixtures tested. In both methods, an underestimation of fetal RhD-positive cells was observed when their expected concentration was ≧0.75%. Conclusion: Though FC is the most sensitive of all techniques, very few laboratories in developing nations can afford such a costly device, so it will be prudent for them to use KBT as the gold standard due to its rapidity, simplicity and affordability.

Gel Technology: An Easy and Useful Method for Estimating Fetomaternal Hemorrhage in the Blood Banks of Developing Nations

Background: Blood bank laboratories in developing countries with limited technical expertise can adapt the simple and rapid gel technology (GAT) to estimate fetomaternal hemorrhage (FMH). We present our experience of the utility of GAT in the detection and measurement of FMH. Methods: Stock solutions (n=17) of 7 serial dilutions containing appropriate concentrations of both fetal RhD positive and adult RhD negative cells were prepared. Both the Kleihauer-Betke technique (KBT) and GAT were performed on all samples. Results: The efficiency of GAT was more appreciated when the fetal cell contamination was ≥0.25%. A calibration curve was developed using a known serial concentration of fetal RhD positive and maternal RhD negative RBCs, which determines the volume of FMH by depicting the agglutination reaction against a particular anti-D dilution. Conclusions: Blood banks using gel technology for red cell serology can adapt GAT to screen FMH.