RESUMEN
BACKGROUND AND OBJECTIVES: The low prevalence antigen, Be(a), is produced by a complex that also produces weak c, e and f (ce). We report here the molecular basis associated with Be(a) antigen expression. MATERIALS AND METHODS: Peripheral blood samples from four Be(a+) probands were tested. Haemagglutination, gDNA extraction, PCR-based assays, reticulocyte RNA isolation, Rh-cDNA analyses, and sequencing were performed by standard procedures. RESULTS: RBCs from Probands 1 and 3 were D-C-E-c+e+, and from Probands 2 and 4 were D+C+E-c+(W)e+. In proband 1, cDNA sequencing of RHCE revealed heterozygosity of nucleotide (nt) 662C/G in exon 5 of RHCE*ce. No other nucleotide changes were observed. As the 662C>G nucleotide change ablates a MscI restriction enzyme cleavage site, PCR-RFLP analysis was performed and the RHCE*ce nt 662C/G heterozygosity was detected on gDNA from the four probands and two children from both Proband 3 and Proband 4. CONCLUSION: The low prevalence Rh antigen, Be(a), is associated with a single nucleotide change in exon 5 of RHCE*ce; that of 662C>G and this change is predicted to alter proline at amino acid position 221 of Rhce to arginine. The fundamental differences in the properties of these two amino acids may impose a steric and/or charge-related effect on the protein, and thereby provide an explanation for the weakened expression of c, e and f (ce) antigens in the Be(a) phenotype.
Asunto(s)
Eritroblastosis Fetal/genética , Exones/genética , Polimorfismo de Nucleótido Simple , Sistema del Grupo Sanguíneo Rh-Hr/genética , Adulto , Alelos , Sustitución de Aminoácidos , ADN Complementario/genética , Femenino , Genotipo , Humanos , Recién Nacido , Masculino , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Embarazo , Análisis de Secuencia de ADNAsunto(s)
Cromosomas Humanos X , Hemofilia B/genética , Eliminación de Secuencia , Adolescente , Secuencia de Bases , Humanos , MasculinoRESUMEN
Anti-basal ganglia antibodies (ABGA) have been associated with poststreptococcal encephalitis similar to encephalitis lethargica (EL). We report two children with parainfectious encephalitis of similar phenotype and IgG ABGA. However, the associated pathogens in the two cases differed; beta-hemolytic streptococcus and herpes zoster. ABGA may not be specific to poststreptococcal encephalitis, but rather a surrogate marker of an inflammatory mediated movement disorder, which may respond to immunotherapy.
Asunto(s)
Autoanticuerpos/metabolismo , Ganglios Basales/inmunología , Herpes Zóster/sangre , Herpes Zóster/fisiopatología , Trastornos del Movimiento/etiología , Infecciones Estreptocócicas/sangre , Infecciones Estreptocócicas/fisiopatología , Adolescente , Niño , Femenino , Humanos , MasculinoRESUMEN
The introduction of the newer generation of electronic cell counters allows the routine reporting of platelet numbers when the peripheral blood count is requested. In a 12-month period, 100 episodes of marked thrombocytosis (platelet count more than 900 X 10(9)/L) were found among 94 children. These patients were young (median age 9 months). All but one episode of marked thrombocytosis occurred as a phenomenon secondary to a variety of disease states. Infections, especially those involving the central nervous systems were the commonest cause of an elevated platelet count in this series. Malignant diseases alone were rarely associated with thrombocytosis of this magnitude. The elevated platelet count began to decline at a mean of 3 days after diagnosis, and no thrombotic or hemorrhagic complications were encountered. Marked thrombocytosis is a benign, common phenomenon in young children, but specific treatment is not required.
Asunto(s)
Trombocitosis/epidemiología , Adolescente , Colombia Británica , Niño , Preescolar , Femenino , Encuestas Epidemiológicas , Humanos , Lactante , Recién Nacido , Masculino , Recuento de Plaquetas , Trombocitosis/etiologíaRESUMEN
Hereditary hemochromatosis was diagnosed in three asymptomatic siblings following the unexpected finding of elevated serum iron concentrations. This diagnosis was confirmed by hepatic biopsy. Repeated phlebotomies resulted in a significant decline of serum iron and ferritin concentrations and a decrease of hepatic iron content. This report and a review of the literature indicate that the diagnosis of hereditary hemochromatosis must be considered more frequently in childhood. Organ dysfunction from iron overload may be minimized in children by the early commencement of regular phlebotomy.
Asunto(s)
Hemocromatosis/genética , Niño , Preescolar , Femenino , Hemocromatosis/sangre , Hemocromatosis/patología , Homocigoto , Humanos , Hígado/patología , Hígado/ultraestructura , Masculino , Microscopía ElectrónicaRESUMEN
We investigated the effect of an intraoperative desmopressin acetate infusion on blood loss after cardiac operation in 60 children, by using a prospective, randomized, double-blind trial. Thirty patients received a desmopressin dose of 0.3 microgram/kg intravenously over 15 minutes at the conclusion of cardiac bypass, and 30 received a saline placebo. The two groups were comparable with respect to age, sex, cardiac lesion, presence of cyanosis, and prevalence of Down's syndrome. Results showed no significant difference in postoperative blood loss between the two groups (30.5 +/- 37.9 ml/kg in the placebo group versus 40.0 +/- 33.1 ml/kg in the desmopressin group). Postoperative bleeding time, total urine output, postinfusion hemodynamics, and postoperative coagulation studies did not differ significantly between the two groups. We conclude that postbypass desmopressin infusion does not reduce blood loss in children undergoing cardiac operations.
Asunto(s)
Procedimientos Quirúrgicos Cardíacos , Desamino Arginina Vasopresina/administración & dosificación , Hemostasis Quirúrgica , Preescolar , Ensayos Clínicos como Asunto , Desamino Arginina Vasopresina/uso terapéutico , Método Doble Ciego , Femenino , Hemorragia/prevención & control , Humanos , Infusiones Intravenosas , Periodo Intraoperatorio , Masculino , Complicaciones Posoperatorias/prevención & control , Estudios Prospectivos , Distribución Aleatoria , OrinaRESUMEN
A simple and reliable technique for removal of ABO incompatible marrow red cells is described. This method requires a blood cell processor and third party red cells are used as a shelf. Using this technique, nine children age 0.5-11.5 years received allogeneic bone marrow transplantation from ABO incompatible donors. A median of 4.8 ml of incompatible red cells were transfused. There was no evidence of a hemolytic transfusion reaction in any patient. A median of 75% of nucleated marrow cells were recovered and used for transplantation. Engraftment occurred at the same time as with ABO compatible transplants. Autologous marrow red cells were reinfused into four young donors. This 'shelf' technique for red cell depletion is an acceptable method for processing small volume, ABO incompatible marrow harvests from pediatric donors.
Asunto(s)
Sistema del Grupo Sanguíneo ABO/inmunología , Células de la Médula Ósea , Trasplante de Médula Ósea/inmunología , Separación Celular/métodos , Eritrocitos/citología , Centrifugación , Niño , Preescolar , Histocompatibilidad/inmunología , Humanos , Lactante , Trasplante AutólogoRESUMEN
Nine normal bone marrow donors aged 7-166 months (median 69 months) received autologous red cells which had been removed from their marrow harvest after collection. The median volume of marrow removed from the donors was 18.6 ml/kg which was equivalent to a median blood volume loss of 23.3%. Three infant donors were transfused with autologous red blood cells intraoperatively. These cells had been salvaged from the initial marrow aliquot and were transfused while bone marrow harvesting continued. No donors required homologous blood transfusion. This technique is useful for marrow donors in the pediatric age group when preharvest autologous blood collection is not feasible or available.
Asunto(s)
Transfusión de Sangre Autóloga , Trasplante de Médula Ósea , Adolescente , Médula Ósea/patología , Niño , Preescolar , Volumen de Eritrocitos , Femenino , Humanos , Lactante , Masculino , Donantes de TejidosRESUMEN
A patient had both lupus anticoagulant hypoprothrombinemia syndrome and celiac disease. The presence of a neutralizing antiprothrombin antibody in the patient's serum was demonstrated by coagulation tests, immunoadsorption, and Western blot analysis. The probable cause for the severe hypoprothrombinemia was clearance of prothrombin-antibody complexes from the circulation. Studies showed the antiprothrombin antibody binding to human prothrombin was phospholipid- and Ca(++)-independent; the antibody did not bind to human thrombin. The target epitope of the antibody was studied by Western blot analysis of mutated recombinant human prothrombin molecules. The antibody reacted with the fragment 2-A region of prothrombin, spanning the second kringle domain and the thrombin A chain within prothrombin. Based on this new method, the proposed mechanism for the neutralizing action of the antibody is impairment of prothrombin activation by the prothrombinase complex, either by steric hindrance of the hydrolysis of prothrombin by factor Xa or by interference of the interaction of prothrombin with factor Va; both reactions are required for efficient conversion of prothrombin to thrombin.
Asunto(s)
Enfermedad Celíaca/complicaciones , Epítopos/química , Inhibidor de Coagulación del Lupus/análisis , Lupus Eritematoso Sistémico/complicaciones , Western Blotting , Niño , Femenino , Pruebas Hematológicas , Humanos , Hipoprotrombinemias/etiología , Protrombina/inmunología , Protrombina/metabolismo , SíndromeRESUMEN
In four cases of delayed delivery of a twin pregnancy with survival of the second twin, the interval ranged at 41-143 days. Review of the literature and our cases supports the following approach: high ligation of the umbilical cord with an absorbable suture, cervical suture in the presence of cervical dilatation, and serial monitoring of fetal growth and maternal coagulation indices. Disseminated intravascular coagulation has not been reported in such cases.
Asunto(s)
Parto Obstétrico/métodos , Gemelos , Femenino , Humanos , Recién Nacido , Masculino , Factores de TiempoRESUMEN
STUDY DESIGN: A prospective study of 147 consecutive patients undergoing spinal surgery who were analyzed for response to an effect of an offered autologous blood program. OBJECTIVES: Analysis of the impact of the autologous program within a comprehensive blood conservation philosophy toward the reduction in the use of homologous blood. METHODS: Each patient was prescreened by the autologous program for inclusions and ability. Physical parameters were recorded as were predonation and postdonation hemoglobin levels. The volume of each donation and the number of autologous and homologous units transfused and total operating blood loss were recorded as were complications during donation and transfusion. RESULTS: One hundred sixteen of the original one hundred forty-seven patients participated in the program and donated between 150 and 1900 ml of blood during the preoperative period. Of these, 35 patients weighed 45 kg or less. Diagnoses included 97 cases of idiopathic scoliosis and the remainder had spinal deformities of other causes. Of the entire group, 13 patients (11%) received homologous blood transfusion, 7 of these patients had diagnoses other than idiopathic scoliosis. CONCLUSIONS: In this study of 116 patients, 89% of the spinal surgeries were successfully completed using only autologous blood. This compared favorably with a historical control group in which 60% of the patients required homologous blood transfusion. It is concluded that the use of autologous blood donation combined with other blood conservation techniques has significantly lessened the need for homologous transfusion.
Asunto(s)
Transfusión de Sangre Autóloga , Escoliosis/cirugía , Enfermedades de la Columna Vertebral/cirugía , Columna Vertebral/cirugía , Adolescente , Pérdida de Sangre Quirúrgica , Transfusión Sanguínea , Niño , Femenino , Hemoglobinometría , Humanos , Masculino , Estudios ProspectivosRESUMEN
The iron status and feeding practices of 434 infants in Vancouver were determined at 39 +/- 1 week of age. Iron-deficiency anaemia (haemoglobin < or = 101 g/L, or < or = 110 g/L with two or three abnormal results from tests of serum ferritin, zinc erythrocyte protoporphyrin and total iron binding capacity) occurred in 7% of infants. Low iron stores (serum ferritin < 10 micrograms/l) occurred in about 24% of infants. Iron-deficiency anaemia was significantly associated (p < 0.001) with duration of breastfeeding. The prevalence of iron-deficiency anaemia among infants breastfed for 8 months was 15%. At 39 weeks (9 months) of age, about 5% and 13% of the infants were bottle-fed with cows milk or low iron infant formula, respectively, and this was also significantly associated (p < 0.02) with low iron stores. Iron-fortified infant cereals had been introduced to 95% of the infants by six months of age. This study shows iron-deficiency anaemia is a problem among a significant number of nine-month-old infants in Canada, and is not explained by failure to introduce iron-fortified infant cereals.
Asunto(s)
Anemia Ferropénica/epidemiología , Canadá/epidemiología , Humanos , Incidencia , Lactante , Fenómenos Fisiológicos Nutricionales del Lactante , Hierro/sangre , Estilo de Vida , Tamizaje Masivo , PrevalenciaRESUMEN
The biopsies from 14 patients with glomerulonephritis with crescents were studied to determine the extent of monocyte involvement in crescent formation. Antiglomerular basement membrane (GBM) disease was diagnosed in six and immune complex (IC) glomerulonephritis in eight. Alpha-Naphthyl acetate staining of frozen sections for nonspecific esterase was done in 11 cases (five anti-GBM and six IC), and the peroxidase-antiperoxidase method for lysozyme was done in two (both IC). Electron microscopy of crescents was carried out in 12 cases. The mean number of nonspecific esterase (or lysozyme-excluding neutrophils) positive cells was 6.0 (+/-5.8) in the anti-GBM cases and 1.1 (+/- 1.4) in the IC ones. The difference was significant (P less than 0.05). By electron microscopy the cellular crescents in cases of anti-GBM disease contained variable numbers of monocytes (macrophages) and epithelial cells. Those from cases of IC disease showed very few monocytes but numerous epithelial cells. The results show that monocytes participate in a numerically significant way in crescent formation in anti-GBM disease but appear to be of minor importance in crescents in IC disease.
Asunto(s)
Glomerulonefritis/patología , Enfermedades del Complejo Inmune/patología , Glomérulos Renales/patología , Monocitos , Anticuerpos , Complejo Antígeno-Anticuerpo , Membrana Basal/inmunología , Esterasas/análisis , Técnica del Anticuerpo Fluorescente , Glomerulonefritis/inmunología , Histocitoquímica , Humanos , Enfermedades del Complejo Inmune/inmunología , Glomérulos Renales/inmunología , Glomérulos Renales/ultraestructura , Microscopía Electrónica , Monocitos/ultraestructuraRESUMEN
Recent studies in experimental glomerulonephritis (GN) suggest that the monocyte is involved in the clearance of detritus and deposits from glomeruli. Whether this concept applies to human GN is unclear because of the paucity of studies in this area. Histochemical evaluation of more than 300 human renal biopsies disclosed eight cases of diffuse proliferative GN which demonstrated relatively large numbers of intraglomerular nonspecific esterase-positive cells. The diagnoses included GN associated with mixed essential cryoglobulinemia (three cases), diffuse lupus GN (three cases), and idiopathic diffuse proliferative GN (two cases). Electron microscopy disclosed extensive deposition of electron-dense material along glomerular basement membranes. Monocytes were present within capillary lumina, were usually associated with visible deposits, and often insinuated themselves between endothelium and the deposits so as to abut the deposits directly. The cells showed evidence of maturation (activation). The contents of the secondary lysosomes were generally similar in structure and density to neighboring deposits, especially in one case in which the deposits had an organized structure. The findings suggest that these monocytes are involved in the clearance of deposits from the glomerulus.
Asunto(s)
Glomerulonefritis/patología , Monocitos/ultraestructura , Membrana Basal/ultraestructura , Crioglobulinas , Técnica del Anticuerpo Fluorescente , Glomerulonefritis/complicaciones , Glomerulonefritis/diagnóstico , Humanos , Glomérulos Renales/ultraestructura , Paraproteinemias/complicaciones , FagocitosisRESUMEN
The transfusion experience for a 1-year period (September 1985 to August 1986) at a tertiary referral obstetric hospital was reviewed retrospectively. During the review period 7731 mothers were delivered and 6003 patients (83%) underwent type-and-screen procedures. A total of 1057 units of red blood cells were crossmatched, and 362 of these 1057 units were transfused to 100 parturient women so that the overall crossmatch/transfusion ratio was 2.9:1. Five percent of transfused patients received 1 unit; 52% of patients received 2 units, 19% received 3 units and 24% received greater than or equal to 4 units of packed red blood cells. Major indications for transfusion were uterine atony, 27%; retained placenta, 17%; trauma, 17%, placenta previa, 7%; and abruptio placentae, 5%. In 12% of patients transfusions were done because of anemia. This study shows the value of audit and confirms that the type-and-screen procedure is an effective way of reducing the crossmatch/transfusion ratio without compromising patient care, even in high-risk patients.
Asunto(s)
Transfusión Sanguínea , Parto Obstétrico , Transfusión de Eritrocitos , Tipificación y Pruebas Cruzadas Sanguíneas , Femenino , Humanos , Embarazo , Estudios RetrospectivosRESUMEN
Fifty-three patients with megaloblastic anaemia treated with cyanocobalamin and folic acid have been studied. Repeat marrow examination was found to be of value in assessing response to treatment. The early improvement in marrow morphology in patients with pernicious anaemia was greater with 1000 mug than with 5 mug doses of cyanocobalamin. The effect of folate deficiency in delaying marrow response to cyanocobalamin in patients with pernicious anaemia is described and combined cyanocobalamin and folic acid treatment was found to be more effective than either alone. The response to large doses of cyanocobalamin in folate deficient patients was unrelated to the initial serum vitamin B12 level.
Asunto(s)
Anemia Macrocítica/tratamiento farmacológico , Anemia Megaloblástica/tratamiento farmacológico , Eritroblastos/patología , Eritrocitos/patología , Vitamina B 12/uso terapéutico , Adulto , Anciano , Anemia Megaloblástica/sangre , Examen de la Médula Ósea , Ensayos Clínicos como Asunto , Femenino , Ácido Fólico/sangre , Ácido Fólico/uso terapéutico , Deficiencia de Ácido Fólico/tratamiento farmacológico , Humanos , Hierro/sangre , Masculino , Persona de Mediana Edad , Factores de Tiempo , Vitamina B 12/sangreRESUMEN
Human renal biopsies (n = 177) were quantitatively evaluated by histochemical means (alpha-naphthyl acetate for nonspecific esterase) for the presence of monocytes within glomerular tufts (excluding crescents). The number of monocytes per glomerulus was counted to obtain the nonspecific esterase index. Histologic, electron microscopic, and direct immunofluorescent features were analyzed. Cases were grouped according to whether intraglomerular electron-dense deposits were present and, if so, their predominant position. Five groups were obtained: group I, subendothelial (39 biopsies); group II, mesangial (24 biopsies); group III, subepithelial (22 biopsies); group IV, intramembranous (2 biopsies); and group V, no detectable deposits (90 biopsies). For each group, the mean nonspecific esterase index was determined: I = 2.0, II = 0.28, III = 0.26, IV = 0.08, and V = 0.13. Group I was subdivided on the basis of whether extensive mesangiocapillary change was present or not. The mean nonspecific esterase index for the group I biopsies without mesangiocapillary change was 2.5, which was significantly higher than the scores for biopsies with mesangiocapillary change (0.2) and those from the other groups (p < 0.01). The results indicate an association between relatively high levels of intraglomerular monocytic infiltration and diseases characterized by having electron-dense immune deposits predominantly in the subendothelial position without extensive mesangiocapillary change. Diseases with predominantly subepithelial, mesangial, intramembranous, or no detectable deposits generally showed low numbers of intraglomerular monocytes.
Asunto(s)
Enfermedades del Complejo Inmune/patología , Enfermedades Renales/enzimología , Enfermedades Renales/patología , Monocitos/patología , Esterasas/metabolismo , Humanos , Glomérulos Renales/patología , Monocitos/enzimologíaRESUMEN
By means of immunoperoxidase histochemistry through monoclonal antibodies, OKT3+ T cells were detected in the cutaneous lesion of a patient with Sezary syndrome. The majority of the infiltrating cells showed positive staining with OKT4 helper cell marker whereas a few OKT8+ cells were also seen. Many OKT6+ Langerhans' cells accumulated in the epidermis overlaying the dermal infiltrate.
Asunto(s)
Anticuerpos Monoclonales , Síndrome de Sézary/patología , Piel/patología , Linfocitos T/patología , Anciano , Biopsia , Humanos , Técnicas para Inmunoenzimas , Masculino , FenotipoRESUMEN
Thirty-five anemic patients with rheumatoid arthritis were studied to determine the relationship between serum ferritin levels and body iron status, as assessed by the grading of bone marrow iron stores. The incidence of greatly reduced or absent marrow iron stores was 60%. Peripheral blood smear, RBC indices, serum iron, and iron binding capacity correlated poorly with stainable marrow iron. Serum ferritin levels only correlated approximately with iron stores, and in iron deficient rheumatoid patients the levels were higher than would be expected in patients with uncomplicated iron deficiency. The study shows that reduced marrow iron stores is common in patients with rheumatoid arthritis, and that the serum ferritin concentration may provide a useful indication of reduced body iron stores in these subjects, but only if a range of normal values can be established for this disease.