Kabita Chatterjee

Prevalence and Specificity of RBC Alloantibodies in Indian Patients Attending a Tertiary Care Hospital.

Background. Red blood cell (RBC) alloimmunization results from genetic disparity of RBC antigens between donor and recipients. Data about alloimmunization rate in general patient population is scarce especially from resource limited countries. We undertook this study to determine prevalence and specificity of RBC alloantibodies in patients admitted in various clinical specialties at a tertiary care hospital in North India. Methods. Antibody screening was carried out in 11,235 patients on automated QWALYS 3 platform (Diagast, Loos, France). Antibody identification was carried out with an 11-cell identification panel (ID-Diapanel, Diamed GmbH, Switzerland). Results. The overall incidence of RBC alloimmunization in transfused patients was 1.4% (157/11235), with anti-E being the most common specificity (36.3%), followed by anti-D (16%), anti-c (6.4%), anti-c + E (6.4%), anti-C + D (5.1%), and anti-K (4.5%). The highest incidence of alloimmunization was observed in hematology/oncology patients (1.9%), whereas in other specialties the range was 0.7–1%. Conclusion. As alloimmunization complicates the transfusion outcomes, authors recommend pretransfusion antibody screening and issue of Rh and Kell matched blood to patients who warrant high transfusion requirements in future.

Retrospective Review of Platelet Transfusion Practices during 2013 Dengue Epidemic of Delhi, India

Background: Dengue infection is a major public health problem. During explosive outbreaks, there is sudden surge in demands of platelet products. The present study was carried out in order to review platelet transfusion practices during the epidemic of dengue. Methods: We retrospectively reviewed the clinical details including the platelet counts and haemorrhagic tendencies of dengue patients as well as the transfusion requirements of diagnosed dengue cases admitted at our centre. Results: A total of 1,750 random donor platelet and 114 single donor platelet units were transfused to 531 patients. 23.2% platelet transfusions were found to be inappropriate Mean dosage of platelets transfused was 2 × 1011 platelets per patient. A total of 347 (65.3%) patients had bleeding diathesis at the time of presentation. Skin and the oropharynx were the most common bleeding sites. Major bleeding was seen in 119 (34.3%) patients, whereas 228 (65.7%) patients had minor bleeding episodes. Conclusion: The study emphasises the need for minimising unnecessary transfusions and for using this scarce resource judiciously, which can be achieved by strict adherence to evidence-based transfusion guidelines and regular review of the on-going transfusion practices.

Evaluation of Mirasol pathogen reduction system by artificially contaminating platelet concentrates with Staphylococcus epidermidis: A pilot study from India

Background and Objectives: This study was conducted to assess the efficacy of Mirasol pathogen reduction system for platelets aimed at preventing bacterial regrowth by spiking buffy coat pooled platelets (BCPP) with clinically relevant load of Staphylococous epidermidis. Materials and Methods: BCPP units were prepared using Teruflex BP-kit with Imugard III-S-PL (Terumo BCT, Tokyo, Japan). Two BCPP units were pooled, of which 40 ml of negative control (NC) was removed. The remaining volume of the platelet unit was inoculated with clinically relevant load of bacteria (total of 30 CFU of S. epidermidis in 1 ml); following this the platelet unit was split into two parts. One part served as positive control (PC) and the other part was subjected to pathogen reduction technique (Mirasol PRT, CaridianBCT Biotechnologies, Lakewood, CO, USA). Bacterial detection was performed using BacT/ALERT system, controls after day 1 and day 7 following inoculation of bacteria and on day 7 for Mirasol-treated unit. Results: Of the 32 treatment cycles, 28 were valid and 4 were invalid. No regrowth was observed in 96.4% (27 of 28) after treatment with Mirasol pathogen reduction system. Of four invalid tests, on two instances the NC showed growth, whereas in other 2 no regrowth was detected in 7th day PC. Bacterial screening of PCs by BacT/ALERT after 24 h of incubation was 28.6%, whereas the effectiveness increased to 100% when incubated for 7 days. Conclusions: Mirasol system was effective in inactivating S.epidermidis when it was deliberately inoculated into BCPP at clinically relevant concentrations. Such systems may significantly improve blood safety by inactivating traditional and emerging transfusion-transmitted pathogens.

Chemiluminescence brings renaissance in TTI screening: Primi experientia

Sir, India with a population of 1.26 billion has seroprevalence rates ranging from 0.2–1%, 0.4–1.09%, and 1.8–4% for HIV, hepatitis C virus (HCV), and hepatitis B virus (HBV), respectively, in the blood donors population.[1‐4] Majority of the blood banks in India are using ELISA‐based serologic screening for transfusion‐transmissible viral infections (TTIs). The automated platform for chemiluminescence (ACLS) has been introduced in the recent past, as a newer serological screening tool that offers good precision, reliability, and high throughput.[5] Although ACLS appears to be an effective replacement for ELISA, the paucity of published research works in support of ACLS, makes this a mere assumption only. Performance evaluation and feasibility assessment of ACLS for routine TTI screening were done at our center based on its concordance with that of ELISA and nucleic acid test (NAT).

Low-density lipoprotein apheresis in a pediatric patient of familial hypercholesterolemia: Primi experientia from a tertiary care center in North India

Familial hypercholesterolemia (FH) is an autosomal dominant disorder due to mutation of apolipoprotein-B receptor gene causing severe dyslipidemia. Lifestyle modification and medical treatment attenuate the disease progression, but as these fail to control the blood cholesterol levels, low-density lipoprotein (LDL) apheresis comes forth as a treatment option. To the best of our knowledge, the following is the very first case of pediatric FH being treated by LDL-apheresis to be reported from India. A severely malnourished female child presented with yellowish skin lesions over different parts of the body, viz., bilateral Achilles tendon, both knees, elbows, both pinnae, and outer canthus of both eyes. She had a strong family history of borderline hypercholesterolemia and was diagnosed as a case of FH. She was maintained on diet modification. LDL-apheresis was planned as the cholesterol levels were not controlled with the diet modificationt. However, unavailability of an appropriate kit in India for LDL-apheresis led to the use of the modified PL1 kit meant for therapeutic plasma exchange procedures. We conducted two sessions of LDL-apheresis. After the first session, the LDL-cholesterol (LDL-C) level fell by 75.9% and the total cholesterol fell by 73.5%. A second procedure led to a decline in total cholesterol level by 18.6% and LDL-C by 19.46%. Subsequently, she was advised diet modification and statin therapy with regular follow-up after every 6 months. Thus, the cascade filtration technique is a safe and effective treatment option for removing the undesired lipoproteins.

Comparison of Procleix Ultrio Elite and Procleix Ultrio NAT Assays for Screening of Transfusion Transmitted Infections among Blood Donors in India

Background. Introduction of nucleic acid testing (NAT) has helped in decreasing window period donations, resulting in increased safety of blood supplies. NAT combines the advantages of direct and highly sequence-specific detection of viral genomes. We analysed the performance of newer Procleix Ultrio Elite (PUE) and Procleix Ultrio assay (PUA) for the screening of the viral markers in our donor population. Material and Methods. 10,015 donor samples were screened by routine immunoassays and both versions of NAT. NAT yields detected were subjected to viral load estimation and to other serological markers. Results. A total of 21 NAT yields were detected; three were positive by both NAT systems, whereas 18 samples were reactive by PUE only. NAT yields include 18 HBV and 3 HCV yields, of which 17 HBV yields were occult infections and 1 was window period (WP) infection. All 3 HCV yields were WP infections. No HIV-1/HIV-2 yield was found. Conclusion. Efficient target capture chemistry in the new TMA assay version significantly improved sensitivity. NAT is superior to serological immunoassays for screening of the viral markers; and the efficient target capture system in the newer TMA assay, namely, the PUE system, has significantly improved sensitivity over the earlier versions.

Response to "Alloimmunisation in thalassaemics: a comparison between recipients of usual matched and partial better matched blood. An evaluation at a tertiary care centre in India".

Dear Sir, Through their article, “Alloimmunisation in thalassaemics: a comparison between recipients of usual matched and partial better matched blood. An evaluation at a tertiary care centre in India”, Pujani et al.1 have raised a topic of great concern for multiply transfused patients such as those with thalassaemia. In most studies from India and other countries, antibodies against Rh and Kell blood group have been found to be the most commonly implicated antibodies. Our institute is also a tertiary care teaching hospital and we too are providing only “ABO and D” matched blood to our thalassaemic patients. We screened the blood of the 255 patients who are registered at our blood bank and are regularly transfused every month with leucoreduced blood. Among these 255 patients, of whom 182 (71.3%) were males and 73 (28.7%) were females, 16 (6.27%) developed a total of 20 red blood cell alloantibodies, including eight anti-E, five anti-c, two each of anti-Fya and Jkb, and one each of anti-K, anti-Lea and anti-D (unpublished data). While 13 patients had one antibody, two patients had two antibodies each (both anti-E + anti-c) and one patient had a combination of three antibodies (anti-E+, anti-K+, anti-Fya). All patients with multiple antibodies invariably had anti-E as one of them. It would, therefore, be a prudent strategy to issue only partially better matched (including all antigens of Rh and Kell group) blood to these thalassaemics patients, which can prevent alloimmunisation in around 70–90% of alloimmunised cases according to various studies2,3. At our institution, antibodies to Rh and Kell antigen accounted for 75% of cases (15 out of 20 antibodies found). Having said that, I would like to point out another striking finding in the study by Pujani et al.1 It was heartening to see that patients in group 2 did not develop any antibodies, but in group 3 of the patients in study, who were shifted to partially better matched blood from usually matched blood, it was really shocking to see that some developed antibodies against Rh and Kell antigens despite these patients having been transfused with blood matched for these antigens for last 2–3 years. Logically, the response of this group should have been similar to that of group 2. The article explains the occurrence of two anti-D antibodies due to exposure of the patients to blood in other hospitals, but does not clarify why other patients, who did not have antibodies earlier and were given Rh and Kell matched blood, developed these antibodies (four patients developed anti-E and one anti-c). One more mesmerising point is that the patients in group 3 developed only those antibodies that were also produced by group 1. As the authors ruled out the possibility of clerical errors and effect of leucodepletion on this issue, the mystery remains unresolved and points to variable responses of the immune system to antigen exposures.