Acute kernicterus in a neonate with O/B blood group incompatibility and a mutation in SLC4A1.

We cared for a term female newborn, who at 108 hours of age, with a total serum bilirubin of 15.4 mg/dL, was discharged from the hospital on home phototherapy. At a return appointment 44 hours later, her total serum bilirubin was 41.7 mg/dL and signs of acute kernicterus were present. Maternal/fetal blood group O/B incompatibility was identified, with a negative direct antiglobulin test, which was positive on retesting. She had abundant spherocytes on blood smear, and these persisted at follow-up, but neither parent had spherocytes identified. A heterozygous SLC4A1(E508K) mutation (gene encoding erythrocyte membrane protein band 3) was found, and in silico predicted to result in damaged erythrocyte cytoskeletal protein function. No mutations were identified in other red cell cytoskeleton genes (ANK1, SPTA1, SPTB, EPB41, EPB42) and the UGT1A1 promoter region was normal. Neurologic follow-up at 2 and 4 months showed developmental delays consistent with mild kernicterus.

Reduced risk for placental malaria in iron deficient women.

BACKGROUND: Nutritional iron deficiency may limit iron availability to the malaria parasite reducing infection risk, and/or impair host immunity thereby increasing this risk. In pregnant women, there is evidence of an adverse effect with iron supplementation, but the few reported studies are strongly confounded. METHODS: A case control study in pregnant Malawian women was undertaken in Chikhwawa southern Malawi in order to describe iron status in relation to placental malaria controlling for several confounding factors. Pregnancy characteristics were obtained and a blood sample at delivery. A full blood count was performed and serum ferritin and transferrin receptor quantified by enzyme-linked immunoassay. DNA analysis was used to identify genetic polymorphisms for ABO phenotype, hemoglobin HbS, and glucose -6 phosphate dehydrogenase deficiency. Placental tissue was obtained and malaria histology classified as active, past or no malaria infection. RESULTS: 112 cases with placental malaria were identified and 110 women with no evidence of placental infection. Iron deficiency was less frequent in women with placental Plasmodium falciparum infection. In those with acute, chronic or past placental infections the odds ratio for iron deficiency was 0.4, 95% CI 0.2-0.8, p = 0.01; for acute and chronic infections 0.4, 0.2-0.8, p = 0.006; for acute infection 0.3, 0.1-0.7, p = 0.001. The association was greater in multigravidae. CONCLUSION: Women with either acute, or acute and chronic placental malaria were less likely to have iron deficiency than women without placental malaria infection There is a priority to establish if reversing iron deficiency through iron supplementation programs either prior to or during pregnancy enhances malaria risk.

Polymorphisms and allele frequencies of the ABO blood group gene among the Jomon, Epi-Jomon and Okhotsk people in Hokkaido, northern Japan, revealed by ancient DNA analysis.

To investigate the genetic characteristics of the ancient populations of Hokkaido, northern Japan, polymorphisms of the ABO blood group gene were analyzed for 17 Jomon/Epi-Jomon specimens and 15 Okhotsk specimens using amplified product-length polymorphism and restriction fragment length polymorphism analyses. Five ABO alleles were identified from the Jomon/ Epi-Jomon and Okhotsk people. Allele frequencies of the Jomon/Epi-Jomon and Okhotsk people were compared with those of the modern Asian, European and Oceanic populations. The genetic relationships inferred from principal component analyses indicated that both Jomon/Epi-Jomon and Okhotsk people are included in the same group as modern Asian populations. However, the genetic characteristics of these ancient populations in Hokkaido were significantly different from each other, which is in agreement with the conclusions from mitochondrial DNA and ABCC11 gene analyses that were previously reported.

Urgent replacement of a mechanical mitral prosthesis in an anticoagulated patient with Bombay red blood cell phenotype.

PURPOSE: Bombay red blood cell phenotype is an extremely rare blood type for which patients can receive only autologous or Bombay phenotype red blood cells. We report a case of urgent repeat sternotomy for replacement of a mechanical mitral prosthesis in a patient with Bombay phenotype anticoagulated with warfarin, to emphasize the transfusion challenges in such patients. CLINICAL FEATURES: A male of Indian descent presented to hospital with New York Heart Association IV symptoms. His medical history revealed previous mitral valve replacement with a mechanical prosthesis in 2005 and Bombay phenotype blood. Preoperative transthoracic echocardiography demonstrated thrombus obstruction of the mitral prosthesis despite anticoagulation with warfarin. Right ventricular systolic pressure was >100 mmHg with 3+ tricuspid regurgitation. The patient's condition was temporized with diuretics, bronchodilators, and bi-level positive airway pressure ventilation while transfusion medicine and cardiac surgery were consulted for urgent surgery. The patient received vitamin K and prothrombin complex concentrate prior to repeat sternotomy and successful mitral prosthesis replacement. After cardiopulmonary bypass, heparinization was corrected with protamine and followed by a second dose of prothrombin complex concentrate and recombinant activated factor VIIa. Postoperatively, the patient received four units of packed red blood cells, two autologous units and two units of Bombay specific red blood cells. Right ventricular pressures stabilized at 40 mmHg following surgery. The patient recovered following several days of inotropic support with milrinone, diuretics, and bronchodilators. CONCLUSION: Patients with Bombay phenotype red blood cells present as type O, but they are unable to receive red blood cells from any phenotype other than Bombay phenotype. They are able to receive all other blood products, including fresh frozen plasma, cryoprecipitate, platelets, prothrombin complex concentrate, and recombinant activated factor VIIa. Coordination between Canadian Blood Services, transfusion medicine, surgery, and anesthesia is important in managing these patients.

An ancient DNA test of a founder effect in Native American ABO blood group frequencies.

Anthropologists have assumed that reduced genetic diversity in extant Native Americans is due to a founder effect that occurred during the initial peopling of the Americas. However, low diversity could also be the result of subsequent historical events, such as the population decline following European contact. In this study, we show that autosomal DNA from ancient Native American skeletal remains can be used to investigate the low level of ABO blood group diversity in the Americas. Extant Native Americans exhibit a high frequency of blood type O, which may reflect a founder effect, genetic drift associated with the historical population decline, or natural selection in response to the smallpox epidemics that occurred following European contact. To help distinguish between these possibilities, we determined the ABO genotypes of 15 precontact individuals from eastern North America. The precontact ABO frequencies were not significantly different from those observed in extant Native Americans from the same region, but they did differ significantly from the ABO frequencies in extant Siberian populations. Studies of other precontact populations are needed to better test the three hypotheses for low ABO blood group diversity in the Americas, but our findings are most consistent with the hypothesis of a founder effect during the initial settlement of this continent.

Autotransfusion performed on a patient with cis AB blood group.

Cis AB blood group is a rare variant of the AB blood group resulting from inheritance of both A and B genes on one chromosome. It may lead to misclassification in ABO grouping and clinical misdiagnosis as a result of its divergence from the laws of Landsteiner and Mendel. We encountered a case of cis AB blood group, and we found that autotransfusion was useful during surgery in this patient with a rare blood group.

ABO hemolytic disease of the newborn: a unique constellation of findings in siblings and review of protective mechanisms in the fetal-maternal system.

Two siblings born 6 years apart presented with similar findings of hepatosplenomegaly, dermal hematopoiesis, hemoglobinuria, and increased platelet consumption, but only moderate anemia and normal serum bilirubin. ABO incompatibility was identified, and other causes were excluded. A review of the current understanding of mechanisms that promote and prevent antibody-mediated hemolysis in the fetus is reviewed. Due to the low ratio of observed to expected significant clinical events among ABO incompatible mother-infant pairs, and the multiplicity of mechanisms that diminish hemolysis, we speculate that severe ABO hemolytic disease of the newborn occurs when there is a specific failure in one of these preventive mechanisms.

Anti-E as a cause of hemolytic disease of the newborn.

A case of HDN caused by anti-E antibody is reported. A group A, E-positive, hemoglobin E trait female infant was born from a group A, E-negative, beta-thalassemia/hemoglobin E mother. Hyperbilirubinemia was noted at the first day of life. The DAT was positive. Anti-E was detected in the maternal serum. Jaundice and anemia occurring to the baby were severe enough to require phototherapy intervention for 9 days and 50 ml of group A, E-negative packed red blood cells was transfused. The baby's condition improved. She was discharged at 12 days of age. Follow-up of the baby at 1 year old showed that she was alive and in good health.

ABO and Rh(D) blood group distribution and their implication for feto-maternal incompatibility among the Palestinian population.

ABO and Rh(D) blood group distribution was evaluated among Palestinian women in the southern area of the West Bank and east Jerusalem. Eleven per cent of women were Rh(D) negative. The review of the last 12,169 deliveries at Makassed Hospital showed that 4.8% of Rh(D)-negative mothers gave birth to Rh(D)-positive infants with haemolytic disease of the newborn. Thirty per cent of A or B infants born to O Rh(D)-positive mothers had a positive direct antiglobulin test with the presence of allo-immune A or B antibody in infant serum. ABO incompatibility was a major reason for phototherapy during the 1st week of life. Results and possibilities for prevention are discussed.

Neonatal jaundice. A second 4-year experience in Toa Payoh Hospital (1986-1989).

A 4-year experience of neonatal jaundice, from 1982-1985, in Toa Payoh Hospital, Singapore was reported previously. The second 4-year experience (1986-1989) of neonatal jaundice is reported. The Department had a more liberal policy in the management of milder cases of neonatal jaundice since 1986, after acquisition of more phototherapy units. It is the purpose of this paper to examine the change in pattern of neonatal jaundice in the same department over these 2 study periods and a comparison is made. The reported frequency of neonatal jaundice in these 2 study periods rose from 7.9% to 10% of all babies in this hospital. Babies who have some form of treatment such as phototherapy are considered as cases of neonatal jaundice. However, the incidence of hyperbilirubinaemia (defined as serum bilirubin level of 255 umol/L or 15 mg/dl or greater) fell from 3.23% to 2.11% of all livebirths in these 2 study periods. ABO Incompatibility, glucose-6-phosphate dehydrogenase (G6PD) deficiency and low birth weights (LBW) remain as the common aetiological factors of neonatal jaundice. The indications of exchange blood transfusions have changed considerably. There were less exchange blood transfusions for severe neonatal jaundice due to G6PD deficiency. However, more LBW babies underwent exchange blood transfusion. No case of kernicterus was reported for more than 10 years.

A note on the presence of blood groups A and B in pre-Columbian South America.

The results of ABO typing in Chilean mummies, a review of published South American paleoserological studies and a systematic discrepancy of admixture estimates based on ABO and Gm genes support the hypothesis that Andean pre-Columbian populations possessed the A (and perhaps the B) gene in small frequencies.

Genetics of the LH red blood cell membrane specificity.

A lectin obtained from seeds of Erythrina lithosperma detects a new specificity, called LH, on the human red blood cell membrane. Family investigations show conclusively that the specificity is under autosomal genetic control, with the gene determining the LH- type being dominant over its allele for the LH+ type.