Detection of bacterial growth in blood components using oxygen consumption as a surrogate marker in a tertiary oncology setup.

Microbiological contamination of blood and blood products is a well-recognised transfusion risk. This study was performed in the blood bank of our oncology centre, with an objective to detect bacterial contamination in our blood products using oxygen consumption as a surrogate marker [Pall Enhanced Bacterial Detection System (eBDS)]. Results revealed that the percentages of failed units were 1.16% for random donor platelets (RDP), 0.81% for single donor platelets (SDP) and 2.94% for packed red blood cells (PRBCs), of which one RDP and one SDP grew coagulase-negative staphylococcus, while one PRBC culture grew Gram-positive bacilli.

Evaluation of hemoglobin of blood donors deferred by the copper sulphate method for hemoglobin estimation.

INTRODUCTION: The copper sulphate (CuSO4) specific gravity test for Hb screening tends to give inappropriate failures. This prompted us to compare it with alternate screening methods. AIM: To study the impact of inaccuracy of CuSO4 method on donor deferral. METHODS: Capillary and venous blood samples of 400 potential blood donors failing the primary Hb screening using appropriately standardized CuSO4 test (specific gravity 1.053) were tested by Hemocue photometer, the Hb colour scale, Cyanmethemoglobin method as well as the automated hematology analyser, which was considered as the standard reference method. RESULTS: One hundred and sixteen donors (29%) who failed the CuSO4 test had true Hb levels >12.5 g/dl. The Hb levels of 131 (32.8%) deferred donors were between 12 and 12.5 g/dl. The sensitivity of Hemocue, Hb colour scale and Cyanmethemoglobin was 99%, 97% and 96% and their specificity was 45%, 93% and 46%, respectively. The positive predictive values (PPV) of Hemocue and Cyanmethemoglobin methods were low (43% and 44%, respectively) but their negative predictive values (NPV) were high (99%, and 97%, respectively). The Hb colour scale had an overall best performance with a PPV of 96% and NPV of 95%. CONCLUSION: The Hemoglobin colour scale which is inexpensive, convenient for field testing and has the overall best performance, is the most suitable for donor Hb screening. Since its readability is 12 g/dl, lowering the donor Hb threshold to 12 g/dl should be actively considered.

Red cell hemolysis during processing and storage.

INTRODUCTION: Apart from the visual assessment, measurement of plasma hemoglobin in the supernatant from red cell units provides an objective measure of the extent of hemolysis during storage. STUDY DESIGN AND METHODS: Packed red cells (N=50), 25 units each in triple (CPD-A1 and SAGM) and quadruple (CPD-A1 and ADSOL) blood bags were evaluated for plasma hemoglobin by the tetramethylbenzidiene (TMB) method on day 1, 7, 14, 21 and 28 of collection. The hemoglobin, hematocrit, MCV, LDH and potassium levels were also noted. Whole blood units (N=25) were used as controls. RESULTS: Hemolysis increased in all the stored red cell units. Plasma hemoglobin increased significantly in the first week of storage. The hemolysis, LDH and potassium levels were found to be significantly higher in the red cell units harvested from the triple blood bags. However, on day 28 of storage, free hemoglobin in all the red cell units was much below the 0.8% hemolysis. CONCLUSION: Hemolysis of the red cells increases due to processing and during storage and is maximum during the first week. Adequate process control and proper storage facilities should be ensured to minimize the hemolysis of red cells during processing and storage.

Plasma exchange for thrombotic thrombocytopenic purpura following hematopoietic stem cell transplantation.

A 17 years old female diagnosed with acute myeloid leukemia (AML)-M2 received an allogeneic haematopoietic stem cell transplant (HSCT) and was given graft versus host disease (GVHD) prophylaxis with methotrexate, cyclosporin-A (CsA) and methyl prednisolone. On day +42 post-transplant, she was diagnosed to have thrombotic thrombocytopenic purpura (TTP). Therapeutic plasma exchange (TPE) (40 ml/kg body mass) using fresh frozen plasma was performed on 8 consecutive days. The renal function, LDH levels, platelet count and peripheral smear findings improved but the neurological symptoms persisted even after TPE. Few reports are available in literature on the effectiveness of therapeutic plasma exchange (TPE) in post-bone marrow transplant (BMT) TTP. The good hematologic response achieved in this patient suggests that TPE could be life-saving and should be tried in every patient with post-BMT TTP.

Correlation of CD34+ cell yield in peripheral blood progenitor cell product with the pre-leukapheresis cell counts in peripheral blood.

INTRODUCTION: Accurate timing of the leukapheresis procedures is of paramount importance to get the best possible CD34+ cell yield in the minimum number of leukapheresis procedures. AIM: To find if pre-harvest CD34+ cell concentration in peripheral blood correlates with CD34+ cells in the product. MATERIAL AND METHODS: Sixty Leukapheresis procedures were performed for 25 patients (8 autologous and 17 allogeneic transplants) with hematological malignancies. Statistical analysis was performed to correlate the pre-harvest CD34+ cell count and the CD34+ cell yield. Volume processed during PBPC harvests was three times the blood volume. RESULTS: The best correlation was found between the leukapheresis product CD34+ cell count and the pre-harvest PB-CD34+ cell count (PCC=0.674) when compared with the other pre-harvest PB cell counts viz., WBC (PCC=0.229) and MNC (PCC=0.324). This correlation was better in the allogeneic harvest (PCC = 0.645) than the autologous harvest procedures (PCC = 0.348). Correlation analysis based on paired samples from the 60 leukapheresis procedures showed that when the pre-leukapheresis PB-CD34+ cell count was >20x10(3)/ul a yield of >1x10(6) CD34+ cells/Kg could be obtained in 95% of the cases and >2x10(6) CD34+ cells /Kg could be harvested in 68% of cases whereas when the pre-leukapheresis PB-CD34+ cell count was <5x10(3)/microl the yield was <1x10(6) CD34+ cells/Kg in 81% of the procedures. CONCLUSION: The yield of CD34+ cells in PBPC harvests depends on the pre-harvest CD34+ cell concentration and therefore it is more useful than the pre-harvest WBC or MNC counts for predicting the appropriate timing of the harvests and also to achieve the best possible yield of CD34+ cells.

Juvenile Huntington's disease.

A rare case of juvenile Huntington's disease manifesting since the age of seven years is reported. The inheritance was typically autosomal dominant as three other members on the paternal side died of similar disease. A definite family history can becrucial in the diagnosis of juvenile Huntington's disease.

Experience with the International League Against Epilepsy classifications of epileptic seizures (1981) and epilepsies and epileptic syndrome (1989) in epileptic children in a developing country.

Four hundred eighty-three epileptic children attending the Pediatric Epilepsy Clinic at Bai Jerbai Wadia Hospital for Children, Bombay, India were classified according to the International League Against Epilepsy (ILAE) classification of epileptic seizures (1981) and epilepsies and epileptic syndromes (1989). The predominant seizures were partial (53.6), generalized (40.3%), and unclassifiable (6%). In epilepsies and epileptic syndromes, 55.3% were partial, 27% were generalized, 13.5% were undetermined, and 4.1% were special syndromes. Although our results were similar in many respects to those of other reported series, some differences were observed in the incidence of partial and generalized seizures, and partial and generalized epileptic syndromes and their subgroups, such as idiopathic, symptomatic, and cryptogenic partial syndromes, idiopathic generalized syndromes, and symptomatic specific syndromes. These differences are probably due to different age limits, methods of case ascertainment and inclusion criteria, different genetic and environmental factors, variable interpretation of clinical and EEG features, and lack of facilities for investigation in developing countries. Despite various limitations, we were able to classify most cases; the ILAE classification can be used in developing countries so that comparison can be made with other studies.

Exchange transfusions via peripheral vessels.

During a 15 month period, partial exchange transfusions (ET) were done in 40 neonates with polycythemia, and double volume ET attempted in 7 neonates with hyperbilirubinemia via peripheral vessels. The procedure was effective and not associated with any complications for partial ET. During double volume ET minor complications were noted in 2 cases, both of whom recovered and subsequently successfully underwent supraumbilical ET. Of the 5 cases who had uneventful double volume exchanges, there was a significant drop in indirect serum bilirubin following the procedure. The mean pre-ET serum indirect bilirubin in these 5 cases was 334 mumol/L and mean post-ET level was 179 mumol/L with a mean drop of 155 mumol/L (46% drop). Technical difficulties in catheterization may be overcome with greater expertise and use of heparin to flush arterial catheters.