Priti Elhence

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.

Root cause analysis of transfusion error: identifying causes to implement changes

BACKGROUND: As part of ongoing efforts to improve transfusion safety, an error reporting system was implemented in our hospital‐based transfusion medicine unit at a tertiary care medical institute. This system is based on Medical Event Reporting System–Transfusion Medicine (MERS‐TM) and collects data on all near miss, no harm, and misadventures related to the transfusion process. Root cause analyses of one such innocuous appearing error demonstrate how weaknesses in the system can be identified to make necessary changes to achieve transfusion safety.

Circulating thrombopoietin levels in normal healthy blood donors and in aplastic anemia patients in relation to disease severity

Background: Thrombopoietin (TPO) is the key hematopoietic growth factor regulating the production of platelets from bone marrow megakaryocytes and maintaining platelet hemostasis. This study was done to find any relationship between the levels of thrombopoietin and the severity of disease in patients with aplastic anemia. Materials and Methods: Serum samples were collected from 52 patients with a confirmed diagnosis of aplastic anemia and 45 normal healthy blood donors of both sexes over a period of 2 years, and TPO was estimated by using commercially available TPO-specific-enzyme-linked immunosorbent assay. Results: The median TPO level of 1190 pg/ml (range 625-7651 pg/ml) in aplastic anemia patients was significantly higher than the median TPO level of 121.1 pg/ml (81.25-237.7 pg/ml) in normal healthy blood donors (P = 0.000). No significant difference was observed in TPO levels of male and female patients (P = 0.453). The median TPO concentrations observed in very severe aplastic anemia, severe aplastic anemia, and nonsevere aplastic anemia were 2765 pg/ml (range 625-6451 pg/ml), 1190 pg/ml (range 672.1-7651 pg/ml), and 1111.5 pg/ml (range 761.1-2289.2 pg/ml), respectively. TPO in patients of very severe aplastic anemia was significantly higher than patients of nonsevere aplastic anemia (P = 0.043), with no significant relation among rest of the groups. Discussion: TPO levels in aplastic anemia patients were significantly higher than in healthy blood donors; however, in aplastic anemia patients TPO levels were significantly higher only in patients with very severe disease.

Cholestasis in a neonate with ABO haemolytic disease of newborn following transfusion of ABO group-specific red cells compatible with neonatal serum: inspissated bile syndrome.

Dear Sir, Alloimmune Rh haemolytic disease of newborn (HDN) has been reported to be a significant risk factor for cholestasis with the published prevalence of cholestasis in neonates with Rh HDN being 13–60%1. However, reports of neonatal cholestasis associated with ABO HDN are rare2. We describe here an interesting case of cholestasis in a blood group “A” neonate born to a group “O” mother; the cholestasis was precipitated by exaggerated haemolysis of transfused blood group “A” red cells which were compatible with the neonate’s serum. A 24-day old female neonate, blood group A RhD-positive, was brought to the paediatric gastroenterology unit of our hospital with severe pallor and jaundice. She was born to a 24-year old, gravida 2, para 1, blood group O positive mother at term by spontaneous vaginal delivery. Her elder sibling had died at 45 days of age with clinical jaundice although the exact cause of death was not known. As shown in Figure 1, jaundice was noticed on the baby’s 3rd day of life and increased progressively, with a slight improvement after phototherapy. A direct antiglobulin test (DAT) done on the neonate’s red cells using the test-tube technique was found to be negative. On day 5 hyperbilirubinaemia was present, caused mainly by unconjugated bilirubin (22.8 mg/dL), which decreased to 9.1 mg/dL on day 8 with phototherapy. The levels of conjugated bilirubin were low and almost constant during the first week. However, on day 8 the neonate’s haemoglobin was found to be 7.2 g/dL and she was transfused two aliquots of 50 mL of group “A” whole blood, which had been found to be compatible with the neonate’s serum by an indirect antiglobulin test (IAT) done using the test-tube technique. Following the transfusion there was a transient rise in the haemoglobin followed by a fall along with increase in unconjugated bilirubin to 11.7 mg/dL, suggesting haemolysis of the transfused group “A” red cells. The baby’s conjugated bilirubin level rose to 33.8 mg/dL on day 11 indicating cholestasis and in the subsequent days the majority of the hyperbilirubinaemia was caused by conjugated bilirubin. In view of the conjugated hyperbilirubinaemia, ursodeoxycholic acid (UDCA) was started. Figure 1 Serial haemoglobin and bilirubin values of the patient. On day 24, the day of admission to our institute, her investigation results were haemoglobin 6.2 g/dL, total leucocyte count 9.4×109/L, reticulocytes 9% and mean corpuscular volume 104.8 fL. Her liver function tests showed total serum bilirubin 26 mg/dL, conjugated bilirubin 14 mg/dL, aspartase amino transferase 175 U/L, alanine amino transferase 102 U/L and gamma glutamyl transpeptidase (GGT) 237 U/L. The baby’s serum lactate dehydrogenase level was elevated (922 U/L), suggesting haemolytic anaemia. Because of her anaemia, at this hospital the baby was transfused with 50 mL of group O RhD-positive packed red cells compatible with her mother’s serum, as determined by an AHG gel column agglutination test (CAT). Her haemoglobin increased and remained stable following the transfusion (Figure 1). The work-up for neonatal cholestasis included DAT for alloimmune haemolysis, urine for non-glucose reducing substances, free haemoglobin in urine, fundus examination for cataract and choreoretinitis, an abdominal ultrasound to look for features of biliary atresia and a hydroxy-iminodiacetic acid (HIDA) scan. Except for the DAT and HIDA scan, all other investigations were non-contributory. Her HIDA scan was non-excretory, suggestive of cholestasis. The neonate’s blood group was confirmed to be A RhD-positive and her red cells were found to be DAT positive (+2) inAHG gel CAT (Diamed GmbH, Cressier, Switzerland). Eluate prepared by heat elution was reactive (+3) with A RhD positive cells by IAT by AHG gel CAT. The IAT done on the neonate’s serum was negative with ID Diacell I-II-II (Diamed GmbH, Cressier) as well as with group A red cells by AHG gel technique indicating no free antibodies in the serum. The mother’s blood group was O RhD positive. The titres of IgG anti-A and anti-B antibodies in the mother were found to be 512 and 1,028, respectively, by AHG gel CAT. As a result of these investigations, ABO HDN was diagnosed, where transfusion of ABO group-specific blood (which was compatible with the neonate’s serum as there was no free maternal anti-A in the neonate’s serum) had led to exaggerated haemolysis. This caused inspissated bile syndrome due to bilirubin overload which triggered cholestasis and conjugated hyperbilirubinaemia. The patient was continued on UDCA (30 mg/kg/day), hydrated and given fat-soluble vitamins along with a medium-chain triglyceride-rich formula. Her jaundice decreased during the follow up. The DAT decreased to 1+ on day 32. At discharge at the age of 42 days her total and conjugated bilirubin levels were 12 mg/dL and 10.4 mg/dL, respectively and at 4.5 months of age her bilirubin was just 1.6 mg/dL and her GGT 82 U/L. In Rh HDN cholestasis is mostly attributed to iron overload due to excessive haemolysis and intrauterine transfusions3. However, risk factors for cholestasis in ABO HDN are not known. In view of the immunohaematological investigations done at our centre our case was diagnosed as ABO HDN. The DAT was however reported to be negative when done earlier at another centre; this could have been because of removal of all DAT-positive neonatal red blood cells by haemolysis or, more likely, because of low sensitivity of the test done by the test-tube method. It is recommended that for all neonates less than 4 months of age pre-transfusion compatibility tests should be performed with maternal serum or, if that is not available, with neonate’s serum or eluate from neonate’s cells4. In keeping with the guidelines, the neonate had received a group A whole blood transfusion which had been cross-matched and found compatible with the neonate’s serum. Nevertheless, the transfused red cells were destroyed extravascularly thereby increasing the hyperbilirubinaemia and indicating the presence of passively acquired maternal IgG anti-A antibodies which were not detected in the neonate’s serum. It is possible that there were no free maternal anti-A antibodies remaining in the neonate’s serum due to adsorption onto the neonate’s red blood cells and group A antigen on vascular endothelium and other tissues. Other reasons could be a false negative test-tube IAT or low sensitivity of the test. However, the fact that the IAT on neonate’s serum done at the time of admission to our centre, in this case using gel CAT, also did not find free maternal anti-A antibodies favours the first explanation. The haemolysis of group A red cells could be more pronounced because adult group A red blood cells express more antigen than do neonatal red blood cells. Because of excessive haemolysis, the excess bilirubin can densify as calcium bilirubinate sludge in bile ducts, leading to cholestasis (inspissated bile duct syndrome)5. Although the ultrasound done 17 days after the incompatible transfusion did not show features of inspissated bile duct syndrome (dilated bile ducts with sludge or echogenic material in the lumen) other features, such as raised levels of liver enzymes, including GGT, the non-excretory HIDA scan and the response to hydration and UDCA are all suggestive of inspissated bile duct syndrome. The response to UDCA may be as early as 2 days and sonographic response has been documented in 6 days. The reason why biliary dilatation was not detected by ultrasound examination in our case could be that the examination was done after 17 days while the baby was receiving UDCA. Other predisposing factors for the development of inspissated bile in neonates include prematurity, parenteral nutrition, sepsis and diuretic therapy5. In most cases removal of the precipitating cause can lead to spontaneous resolution of biliary sludge. However, refractory cases may require surgery or other endoscopic procedures5. In our case no other predisposing factors, except haemolysis, were present. ABO HDN is a relatively mild disease with low morbidity and mortality; however, failure to diagnose and to follow compatibility requirements can complicate the outcome by precipitating neonatal cholestasis. In summary, this case demonstrates that, in ABO HDN, blood found to be compatible with the neonate’s serum may actually be incompatible and become haemolysed. Thus, prior to transfusion of ABO-specific red blood cells in neonates less than 4 months of age compatibility testing should be done by IAT, preferably using the mother’s serum or eluate from neonate’s red cells; otherwise, only group O red blood cells should be transfused.

RhD blocking phenomenon implicated in an immunohaematological diagnostic dilemma in a case of RhD-haemolytic disease of the foetus

Of all red blood cell antigens, RhD is second only to the ABO antigens in importance in blood transfusion. The Rh antigens are fully expressed at the time of birth unlike the weak expression of ABO antigens in neonates1. Immunisation to D antigen can occur in reaction to less than 0.1 mL of foetal blood, resulting in anti-D alloantibody in the maternal circulation2. Haemolytic disease of the foetus and newborn (HDFN) occurs when there is a destruction of foetal/neonatal red cells by IgG antibodies produced by the mother. When Anti-D is the cause of HDFN, the severe anaemia can cause foetal hydrops, tissue hypoxia and even foetal death in utero3. Sensitised pregnant women require close monitoring for early detection of foetal anaemia and to decide whether and, if so, when intrauterine transfusion is required. As a key part of any pre-transfusion testing, the ABO and RhD groups of recipient samples are determined. It has been reported that if a neonate’s red cells are heavily saturated with IgG antibodies, RhD typing with anti-D reagents may give either false negative or false positive results3. We report here the case of blocked RhD in a cord blood sample in a suspected case of RhD-HDFN which was detected in our hospital blood bank laboratory.

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.

Error reporting in transfusion medicine at a tertiary care centre: a patient safety initiative.

Abstract Background: Errors in the transfusion process can compromise patient safety. A study was undertaken at our center to identify the errors in the transfusion process and their causes in order to reduce their occurrence by corrective and preventive actions. Methods: All near miss, no harm events and adverse events reported in the ‘transfusion process’ during 1 year study period were recorded, classified and analyzed at a tertiary care teaching hospital in North India. Results: In total, 285 transfusion related events were reported during the study period. Of these, there were four adverse (1.5%), 10 no harm (3.5%) and 271 (95%) near miss events. Incorrect blood component transfusion rate was 1 in 6031 component units. ABO incompatible transfusion rate was one in 15,077 component units issued or one in 26,200 PRBC units issued and acute hemolytic transfusion reaction due to ABO incompatible transfusion was 1 in 60,309 component units issued. Fifty-three percent of the antecedent near miss events were bedside events. Patient sample handling errors were the single largest category of errors (n=94, 33%) followed by errors in labeling and blood component handling and storage in user areas. Conclusions: The actual and near miss event data obtained through this initiative provided us with clear evidence about latent defects and critical points in the transfusion process so that corrective and preventive actions could be taken to reduce errors and improve transfusion safety.

Posterior reversible encephalopathy syndrome following blood transfusion in a patient with factor X deficiency: Is it an unusual systemic manifestation of an adverse transfusion reaction?

Adverse neurological transfusion reactions including posterior reversible encephalopathy syndrome (PRES) following blood transfusion are rare. Our case an 18-year-female with known Factor X deficiency with menorrhagia developed severe hypertension, followed by generalised tonic clonic convulsions apparently after blood component transfusion. She had earlier received 4 units of red blood cells (RBC) for anaemia and 10 units of fresh frozen plasma (FFP) for menorrhagia (with prolonged PT and APTT) within short span of time at another hospital. There was no history of hypertension, convulsions, any cardiovascular, renal or neurological disease before transfusion. The clinical features and magnetic resonance imaging findings led to the diagnosis of PRES. Abnormal electroencephalogram and a hypercoagulable haemostatic profile on thromboelastography along with derangement in blood glucose and liver function tests were also observed. Patient responded well to the anticonvulsants and antihypertensive agents prescribed and was discharged in a stable condition. Our patient had a systemic transfusion reaction involving predominantly neurological system, however, cardiovascular, hepatic, haemostatic and endocrine systems were also affected. This case is unusual being the first report of PRES occurring in a patient with factor X deficiency presenting with an array of clinical and laboratory features which have not been reported in earlier studies involving PRES. Presumably the initial aggressive red cell transfusion to treat anaemia initiated the crisis and further large volumes of transfused FFP contributed to this adverse transfusion reaction in our case. Clinicians and Transfusion Medicine specialists should be aware about this uncommon clinical entity.

Cross-match-compatible platelets improve corrected count increments in patients who are refractory to randomly selected platelets

BACKGROUND Cross-match-compatible platelets are used for the management of thrombocytopenic patients who are refractory to transfusions of randomly selected platelets. Data supporting the effectiveness of platelets that are compatible according to cross-matching with a modified antigen capture enzyme-linked immunosorbent assay (MAC-ELISA or MACE) are limited. This study aimed to determine the effectiveness of cross-match-compatible platelets in an unselected group of refractory patients. MATERIALS AND METHODS One hundred ABO compatible single donor platelet transfusions given to 31 refractory patients were studied. Patients were defined to be refractory if their 24-hour corrected count increment (CCI) was <5×10(9)/L following two consecutive platelet transfusions. Platelets were cross-matched by MACE and the CCI was determined to monitor the effectiveness of platelet transfusions. RESULTS The clinical sensitivity, specificity, positive predictive value and negative predictive value of the MACE-cross-matched platelets for post-transfusion CCI were 88%, 54.6%, 39.3% and 93.2%, respectively. The difference between adequate and inadequate post-transfusion 24-hour CCI for MACE cross-matched-compatible vs incompatible single donor platelet transfusions was statistically significant (p=0.000). The 24-hour CCI (mean±SD) was significantly higher for cross-match-compatible platelets (9,250±026.6) than for incompatible ones (6,757.94±2,656.5) (p<0.0001). Most of the incompatible cross-matches (73.2%) were due to anti-HLA antibodies, alone (55.3% of cases) or together with anti-platelet glycoprotein antibodies (17.9%). DISCUSSION The clinical sensitivity and negative predictive value of platelet cross-matching by MACE were high in this study and such tests may, therefore, be used to select compatible platelets for refractory patients. A high negative predictive value demonstrates the greater chance of an adequate response with cross-matched-compatible platelets.

Late onset neonatal anaemia due to maternal anti-Kpb induced haemolytic disease of the newborn

BACKGROUND Alloanti-Kp(b) is a rare, clinically significant antibody against high frequency red cell antigen Kp(b) of Kell blood group system. We report here a case of Haemolytic disease of newborn (HDN) due to anti-Kp(b), which manifested as severe anaemia at the age of 1 month. AIM To diagnose and successfully manage anti-Kp(b) induced HDN. METHODOLOGY Direct antiglobulin test (DAT), antigen typing, irregular antibody screening and identification were done by polyspecific LISS Coombs Gel card and standard methods. RESULTS At presentation the neonate had severe anemia with reticulocytopenia. Blood group was B, Rh D positive and DAT was 2+. Anti-Kp(b) was detected in mothers serum. Due to unavailability of Kp(b) negative red cells and incompatible blood group of mother (A(1)B Rh D positive) infant was transfused group B Rh D, Kp(b) positive PRBCs under steroid cover. He was symptom free at 4 months of age and DAT became negative at 6 months. CONCLUSION Anti-Kp(b) is capable of causing severe late HDN. Infants born to irregular antibody positive mothers should be investigated and closely monitored for several weeks after birth for immune HDN even if asymptomatic at birth.