Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0029713 (immaturity)
 4,335 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Rare forms of incompatibility were observed over a period of 20 years in 41 (2%) of 2088 new-borns with haemolytic disease. Antibodies involved were anti-c (n = 27), anti-E (n = 6) and anti-K (n = 4), as well as one case each of anti-E + Fya, -C, -Fya and -Jka. Amniotic fluid was examined during pregnancy in nine cases, three children were given intra-uterine infusions, while in the remainder the haemolytic process was mild or only moderately severe. One infant died of toxoplasmosis, another one of immaturity and respiratory distress syndrome. Kernicterus was always prevented. In haemolytic disease of the newborn caused by anti-c and anti-E, prenatal damage is markedly rarer than with D erythroblastosis, but must be considered during the pregnancy. In anti-K haemolytic disease the severity of the disease is similar to that of D erythroblastosis. All three incompatibilities may lead to kernicterus in the first few days after birth so that exchange transfusions are often necessary. In most of the other incompatibilities the course is similar to that seen with ABO erythroblastosis.
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PMID:[Haemolytic disease of the new-born by blood-factor incompatibility other than Rh(d) and ABO (author's transl)]. 82 15

We report on a female preterm infant with hepatic failure and neonatal tissue siderosis of hemochromatotic type diagnosed by using both histochemistry and atomic absorption spectroscopy. The infant presented with meconium ileus, signs of rapidly progressive hepatic failure, and hyperferritinemia (7132 ng/ml). Despite surgery and intensive care the infant died 32 days after birth. Postmortem examination showed a wrinkled liver with extensive collapse of the hepatic architecture and regenerating nodules as well as hepatic and extrahepatic iron accumulation of hemochromatotic type, sparing the reticuloendothelial system. Atomic absorption spectroscopy confirmed an increase in the iron content of various organs: liver, heart, pancreas, oral salivary gland, kidney, and adrenal gland. The increase in the iron content of various organs was determined by comparing the analysis of the propositus with those of 5 gestationally age-related preterm infants who had died in the intensive care unit: 2 died of meconium aspiration syndrome, the other 3 of hyaline membrane disease, bronchopulmonary dysplasia, and immaturity, respectively. We also compared the analysis of 15 fetuses having a a condition predisposing to iron accumulation (trisomy 21, trisomy 18, cytomegalovirus, amnion infection syndrome, Rhesus- and ABO-incompatibility, congenital hemolysis, anti-phospholipid syndrome, congenital heart disease). Delta F508, the most frequent mutation seen in cystic fibrosis patients, was excluded by gene sequencing. Different noxae causing iron accumulation in the neonatal period have led to the statement that neonatal hemochromatosis may collect different etiologies, such as metabolic disorders, infections, chromosomal aberrations, and immunological disorders. In this study, we report the singular evidence of neonatal iron accumulation of hemochromatotic type in an infant presenting with meconium ileus and propose a classification of the neonatal disorders associated with iron accumulation.
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PMID:Hepatic failure with neonatal tissue siderosis of hemochromatotic type in an infant presenting with meconium ileus. Case report and differential diagnosis of the perinatal iron storage disorders. 1170 Aug 92

Infants with fatal cardiac disease often die awaiting transplantation because of the shortage of donor hearts. The Hospital for Sick Children (HSC), Toronto, Canada, has researched and applied the concept of crossing the blood group compatibility barrier. Heart transplantation at HSC unrestricted by ABO compatibility greatly contributed to decreasing the mortality rate among infants on the waiting list from 58% to 10%. From January 1996 to January 2002, 16 infants less than 14 months of age received ABO-incompatible heart transplants at our institution. The cardiopulmonary bypass (CPB) circuit is primed with additional volume to replace the patient's blood volume. Packed red blood cells (PRBC) used in priming must be ABO-compatible with the recipient. All plasma components and platelets must contain no anti-A or anti-B antibodies to donor or recipient. CPB is initiated and the patient's venous blood is collected into a transfusion bag and sent to the blood bank. The total amount collected should be one and a half to two times the patient's blood volume. The plasma is separated and discarded, returning only the PRBC, thus reducing the concentration of circulating antibodies to blood group antigens. Our team has experienced an 87% survival rate with this technique. The success is believed to be associated with the recipients' immunologic immaturity. Newborns do not produce isohemagglutinins, and serum anti-A and anti-B antibody titers usually remain low until 12-14 months of age. The complement system is not fully developed, therefore, the mediators of hyperacute rejection are absent during early infancy. Heart transplantation unrestricted by the need for ABO compatibility would effectively expand the available donor pool and decrease waiting times.
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PMID:ABO-incompatible heart transplantation: a perfusion strategy. 1507 58

In order for ABO-incompatible organ transplantation to be performed successfully, the antibody response must be targeted. Aggressive strategies are usually required both to remove pre-existing antibodies directed at donor A/B antigens and to suppress further production of antibodies. If this can be accomplished in the short-term, graft accommodation of ABO-incompatible transplants may develop upon eventual re-accumulation of antibodies as the graft acquires resistance to antibody-mediated damage. In contrast to mature individuals, very young infants lack isohemagglutinins due to a natural lag in development of immunity to T cell-independent polysaccharide antigens. This delay in maturation permits a window of safety during which infants can receive ABO-incompatible grafts without the requirement for aggressive immunosuppressive strategies. We have recently demonstrated that ABO-incompatible heart transplantation performed during this stage of immaturity is followed by the spontaneous development of donor-specific B cell tolerance rather than graft accommodation, and that tolerance in this setting occurs by a cellular mechanism of antigen-specific B cell elimination. This finding is strikingly similar to the original descriptions of neonatal T cell tolerance in mice. Our data provide compelling justification that every effort should be made to include juvenile recipients routinely as subjects in tolerance research. Through understanding the mechanisms underlying tolerance in this setting, as with murine models of neonatal tolerance originally described by Medawar and colleagues, it may be possible to expand the potential applications of tolerance strategies to older patient populations.
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PMID:Targeting antibody-mediated rejection in the setting of ABO-incompatible infant heart transplantation: graft accommodation vs. B cell tolerance. 1597 36

In the pediatric age group shortage of donor hearts leads to mortality rates of 30-50% on the waiting list. Because of the immaturity of the immune system of infants, ABO-incompatible heart transplantation may be an option to increase donor availability. We transplanted two infants with blood type O at the age of 7 and 5 months, respectively, with complex congenital heart disease. Intraoperative plasma exchange was performed during cardiopulmonary bypass followed by standard immunosuppression. Both recipients received a blood type A donor organ. Plasma was exchanged up to six times until anti-A antibodies were eliminated. No hyperacute rejection occurred, ventricular function is excellent and there have been no acute rejection episodes up to 4 months after transplantation. Anti-A antibody titers remained low and eventually disappeared. ABO-incompatible cardiac transplantation shows good short-term results in young infants and appears to be a safe procedure to reduce mortality on the waiting list.
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PMID:Successful ABO-incompatible heart transplantation in two infants. 1616 9

Heart transplantation in infancy is generally associated with excellent clinical results. Unfortunately, heart transplantation cannot be offered to many infants who would benefit from this therapy due to a shortage of organ donors of suitable size for infants, and traditional limitations that constrain donor availability still further, such as the requirement for ABO-compatibility. At the Hospital for Sick Children, we questioned the need to apply this requirement to infants, based on available scientific evidence regarding the immaturity of certain immune responses. Our experience with 23 ABO-incompatible infant heart transplants demonstrates that this procedure can be performed safely in infants. Moreover, we have shown that donor-specific B-cell tolerance develops following ABO-incompatible transplantation. The consistency of the clinical and laboratory outcomes of ABO-incompatible infant heart transplantation to date would suggest that there is no scientific rationale to require ABO-compatibility between donors and recipients for infant transplantation.
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PMID:Crossing the ABO barrier in infant heart transplantation at the Hospital for Sick Children. 1670 55

A best evidence topic (BET) in cardiac surgery was written according to a structured protocol. The question addressed was whether ABO-incompatible (ABO-I) heart transplant recipients have a similar survival rate as an ABO-compatible (ABO-C) transplant in the pediatric population <1 year of age. Altogether more than 112 papers were found using the reported search, of which 10 represented the best evidence to answer the clinical question. Generally, ABO-I transplantation has been associated with the neonatal population because of the relative immaturity of the immune system for the first year of life. In the BET the search-term 'pediatric' was used as a method to ensure retrieval all relevant papers. However, the vast majority of the patients reviewed were <1 year of age with specific techniques undertaken to modulate preoperative, intraoperative and postoperative isohemagglutinin titer levels with rejection monitoring. Therefore, the BET conclusions should not be applied to the pediatric group as a broad age classification. Two large series are of particular interest. Patel et al. reviewed all primary heart transplantation recipients < or =1 year of age in the United Network for Organ Sharing/Organ Procurement and Transplantation Network (UNOS/OPTN) registry (ABO-I=35 vs. ABO-C=556). There was no difference in 30-day mortality (ABO-I=5.9% vs. ABO-C=8.8%; P=0.55); one-year mortality (ABO-I=16.6% vs. ABO-C=14.7%; P=0.77); graft rejection (ABO-I=1 vs. ABO-C=0); and graft failure (ABO-I=24% vs. ABO-C=24%; P>0.99). Three-year Kaplan-Meier survival was 70% (P=0.85). Propensity score adjusted analysis did not implicate ABO-I as a predictor of mortality [hazard ratio (HR)=3.6, confidence interval (CI): 0.2-49.0; P=0.33]. The ABO-I group demonstrated an increased need for pacemaker (ABO-I=3.1% vs. ABO-C=0.4%; P=0.03) and higher stroke rate (ABO-I=12.9% vs. ABO-C=1.3%; P<0.0001). Dipchand et al. published the results of the Toronto cohort from 1992 to 2006 (ABO-I=16 vs. ABO-C=38). The median age at transplantation (ABO-I=88 days vs. ABO-C=84 days; P=0.82) and the number of neonatal transplant recipients (ABO-I=17% vs. ABO-C=22%; P=0.59) was similar. The freedom from post-transplantation death or retransplantation was equivalent at one year (ABO-I=77% vs. ABO-C=84%) and seven years (ABO-I=74% vs. ABO-C=74%; P=0.87). No significant difference was observed for the five-year freedom from: rejection (ABO-I=60% vs. ABO-C=45%; P=0.41); renal dysfunction (ABO-I=67% vs. ABO-C=72%; P=0.70); allograft vasculopathy (ABO-I=87% vs. ABO-C=78%; P=0.45); and post-transplantation lymphoproliferative disorder (PTLD) (ABO-I=87% vs. ABO-C=86%; P=0.93). We conclude that ABO-I transplantation is comparable to ABO-C transplantation, with several retrospective papers concluding there is no difference in mortality, morbidity or graft failure in the pediatric population <1 year of age.
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PMID:Does ABO-incompatible and ABO-compatible neonatal heart transplant have equivalent survival? 2030 66