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Query: UMLS:C0039730 (thalassemia)
 10,305 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Sickle cell disease is numerically as common as thalassaemia. However, it affects relatively under privileged population i.e. tribal population belonging to economically poor class and having inadequate access to education and modern health facilities. A recent explosion acknowledged in understanding the pathogenesis of this disease has lead to newer dimensions in treatment. Some of these viz. prevention of overwhelming bacterial infection, present indications and controversies regarding blood transfusion, prevention of stroke, acute chest syndrome, hydroxyurea therapy--probably the best disease modifying agent at the moment, stem cell transplantation--a cure and certain promising experimental therapies including gene therapy have been discussed in this review.
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PMID:Advances in management of sickle cell disease. 1451 86

The distribution of clinical features was examined in subjects with homozygous sickle cell (SS) disease in the Jamaican Cohort Study to determine whether there is evidence of distinct clustering of symptoms or clinical phenotypes. A twofold model yielded groups that could be interpreted as painful crisis or leg ulcer phenotypes and 78% of patients were classified with 95% confidence into one of these. The painful crisis phenotype also manifested higher frequencies of dactylitis, meningitis/septicaemia, acute chest syndrome and stroke. Attempts to define a three-group model were less convincing although 43% of patients could be allocated with 95% confidence. The three-group model essentially divided subjects with the leg ulcer phenotype into subgroups with higher and lower frequencies of painful crisis, dactylitis, meningitis/septicaemia and acute chest syndrome. In the three-group model, the painful crisis phenotype had lower total haemoglobin, fetal haemoglobin, mean cell volume and higher reticulocytes but there was no apparent influence of alpha thalassaemia or beta globin haplotype. Both environmental and genetic factors are likely to contribute to most manifestations of SS disease and the evidence for different clinical phenotypes suggests that a search for associated genetic polymorphisms may provide insights into the mechanisms of clinical variability in SS disease.
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PMID:Are there clinical phenotypes of homozygous sickle cell disease? 1528 56

The long-term efficacy and toxicity of hydroxyurea for infants are undefined, and its role in preventing organ dysfunction is unknown. Short-term feasibility of hydroxyurea administration, toxicities, hematologic effects, and effect on spleen function in infants with sickle cell anemia (SCA) were reported (Hydroxyurea Safety and Organ Toxicity [HUSOFT] trial). These infants completing 2 years of hydroxyurea therapy (20 mg/kg/d) were offered study extension with dose escalation to 30 mg/kg/d. Patients were monitored with laboratory tests and biannual imaging studies. Hematologic indices were compared with predicted age-specific values and event rates compared with historic rates. All 21 subjects completing the original trial enrolled in the extension study: median age, 3.4 years old (range, 2.6 to 4.4 years); 12 females; 20 with Hb SS, 1 with Hb S/beta0-thalassemia. Seventeen patients completed 4 years of hydroxyurea, and 11 completed 6 years. After 4 years, hydroxyurea was associated with increased hemoglobin concentration, percentage of fetal hemoglobin (Hb F), and mean corpuscular volume (MCV) and decreased reticulocytes, white blood cells (WBCs), and platelets (P < .01). Patients experienced 7.5 acute chest syndrome (ACS) events per 100 person-years, compared with 24.5 events per 100 person-years among historic controls (P = .001). Treated patients had better spleen function than expected and improved growth rates. Infants with SCA tolerate prolonged hydroxyurea therapy with sustained hematologic benefits, fewer ACS events, improved growth, and possibly preserved organ function.
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PMID:Long-term hydroxyurea therapy for infants with sickle cell anemia: the HUSOFT extension study. 1617 53

Individuals with sickle cell disease (SCD) may have oxyhaemoglobin desaturation during the steady-state, the causes of which are incompletely known. We studied a cohort of 585 children who have sickle cell anaemia (SS), sickle beta0-thalassaemia (Sbeta0), sickle-haemoglobin C disease (SC), or sickle beta+-thalassaemia (Sbeta+) to determine the relationships between steady-state oxyhaemoglobin saturation (SpO2) and SCD genotype, age, gender, steady-state haemoglobin (Hb) and reticulocyte count, and rate of acute chest syndrome (ACS). The SS/Sbeta0 group (n = 390) had lower mean SpO2 than the SC/Sbeta+ group (n = 195) (96.3% vs. 98.7%, P < 0.001). Among SS/Sbeta0 subjects, a decrease in steady-state SpO2 correlated with a decrease in Hb, an increase in reticulocytes, older age and male gender. These correlations were not found in the SC/Sbeta+ group. Prior ACS did not correlate with steady-state SpO2. A multivariate model explained 45% of the variability in SpO2, but only 5% of the variation in SpO2 was explained by Hb. We conclude that steady-state desaturation is common in individuals with SCD, but it appears to be unrelated to prior episodes of ACS and largely unexplained by chronic anaemia.
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PMID:Clinical correlates of steady-state oxyhaemoglobin desaturation in children who have sickle cell disease. 1617 73

We analyzed the records of 153 Guadeloupean children with sickle cell anemia (SCA), for whom clinical and laboratory data were prospectively collected (mean follow-up duration 8.4 +/- 4.6 yr). Prevalence and age-specific frequencies of acute clinical events were determined and correlations between complications, hematological parameters and potential modulating factors investigated. Painful crisis and acute chest syndrome (ACS) were the two most common complications, affecting 65.4% and 58.8% of the patients, respectively. The frequency of acute anemia was 49.7% (acute splenic sequestration 24.8%; acute aplastic anemia 15.0%). Prevalences of septicemia-meningitis and osteomyelitis were 15.7% and 16.3%, respectively. A higher incidence of infections, painful crises and acute anemia was detected in patients who developed ACS. The well-documented protective effect of HbF level on the overall disease expression was observed with higher HbF level in asymptomatic than in symptomatic patients (17.5% +/- 8% vs. 9.9% +/- 6.4%, P = 0.01) with similar ages and sex ratio. It was also confirmed on ACS and, for the first time, further extended to acute anemic events and septicemia. Besides its effect on hematological parameters, alpha-thalassemia seems to have little impact on the prevalence of complications, as do beta(S)-globin haplotypes. Comparison with other series suggests that the natural history of SCA in Guadeloupe is more similar to that in Jamaica with regard to those reported in Europe and the United States, suggesting a potential impact of environmental factors on the clinical course of the disease.
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PMID:Sickle cell anemia in Guadeloupean children: pattern and prevalence of acute clinical events. 1645 94

Sickle cell anemia (SS) is highly phenotypically variable, and early predictors of outcome could guide clinical care. To determine whether early vaso-occlusive complications predicted subsequent adverse outcomes in the Dallas Newborn Cohort, we studied all members with SS or sickle-beta0-thalassemia who presented in their first year of life and had 5 years or more of follow-up. We defined 3 potential early predictors: hospitalizations in the first 3 years of life for (1) painful events other than dactylitis, (2) dactylitis, and (3) acute chest syndrome (ACS). We studied the associations of these predictors with the following late adverse outcomes (occurring after the third birthday): death, first overt stroke, use of disease-modifying therapy, and hospitalizations for pain events and ACS. None of the early events predicted death or stroke. Early pain and ACS both predicted a modest, temporary increase in the number of later painful episodes, but early ACS strongly increased the odds of more frequent ACS throughout childhood. Dactylitis had limited utility as a predictor. Although we still lack a useful prognostic framework for young children with SS, those who experience early ACS might be candidates for higher risk interventions to mitigate or cure their disease.
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PMID:Prognostic significance of early vaso-occlusive complications in children with sickle cell anemia. 1694 Apr 26

Women with sickle cell anemia are surviving longer and may desire pregnancy. Rare, life-threatening complications of sickle cell anemia, such as acute chest syndrome, may occur at the time of delivery. A 22-year-old woman with sickle cell (HbS/beta+ thalassemia) at 35 weeks of gestation presented with shortness of breath and generalized pain. She was diagnosed with vasoocclusive crisis and acute chest syndrome, managed with exchange transfusion and cesarean delivery, and discharged home with her newborn one week later. Prompt recognition of life-threatening complications of sickle cell anemia in a pregnant woman and collaborative medical and obstetric management are essential to optimize maternal and fetal outcome.
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PMID:Sickle cell vasoocclusive crisis and acute chest syndrome at term pregnancy. 1726 34

An infant with Hb SE disease is reported. He was clinically well. Review of the literature shows that patients aged 18 and younger are usually well. On the other hand, more than half of those aged 20 and older developed sickling-related complications, including potentially life-threatening acute chest syndrome. These patients have 60-65% Hb S, similar to the percent Hb S in patients with Hb S/beta(+)-thalassemia. Their hematological features and clinical course appear to parallel those of Hb S/beta(+)-thalassemia. Patients have variable levels of anemia, and some develop clinical complications. With population migrations and increasing racial intermarriages, Hb SE disease is expected to be encountered more often around the globe. Patients with Hb SE disease should be followed and managed in a similar fashion as those with Hb S/beta(+)-thalassemia, and treated appropriately when they develop sickling-related symptoms and complications.
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PMID:Hemoglobin SE disease: a concise review. 1727 12

The paucity of clinical reports in the world literature suggests that, as a disease entity, haemoglobin SE compound heterozygosity is of negligible importance. In view of the significant community prevalence of this haemoglobinopathy in the Sultanate of Oman where it is the second most prevalent sickling disorder, a hospital study of 12 SE compound heterozygotes from six unrelated Arab families was undertaken to determine their clinico-haematological features. Our findings were compared with those reviewed in the literature. Clinical and haematological evaluation was carried out by conventional methods including chromatographic haemoglobin analysis. At least 50% of those studied were asymptomatic throughout the study period but sickling-related complications occurred in the rest and included the acute chest syndrome (1/12), severe vaso-occlusive skeletal pain (2/12), frontal bossing (1/12) possibly indicative of significant chronic haemolysis and recurrent infections of the urinary tract (1/12). Steady-state haemoglobin levels fell within the reference range while MCV and MCH values were, as expected, reduced in most cases; nevertheless, concomitant inheritance of alpha-thalassaemia trait was also likely. Red cell morphology was striking by the absence or rarity of pseudo-sickled cells in the blood films of many patients during the steady state and in crises. Bearing in mind the prevalence of 0.05% of SE compound heterozygosity in Oman, the findings in this single study of the largest number of SE patients and their relatives confirm the predominantly asymptomatic nature of this sickling disorder in individuals in the community at large. HbF levels do not appear to explain the heterogeneous nature of this haemoglobinopathy. Correlation of the variable clinical and haematological features of SE cases with their alpha-globin gene status and beta-cluster haplotypes (linked to the beta(s)- and beta(e)-genes) merits a separate investigation, which is being currently organized.
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PMID:Sickle cell-haemoglobin E (HbSE) compound heterozygosity: a clinical and haematological study. 1761 80

Jsb is a high-frequency antigen. Anti-Jsb is a rare alloantibody, and its clinical significance is poorly documented. We report a case in which a 12-year-old boy of Nigerian descent with sickle beta- thalassemia presented with multiple alloantibodies, including a panagglutinin and acute chest syndrome, necessitating the emergent transfusion of five units of phenotype-similar, crossmatchincompatible RBCs, four of which were given during an exchange transfusion. The patient was later found to have anti-Jsb. In addition to routine serologic methods to study the patient's RBCs and plasma, a monocyte monolayer assay (MMA) was performed on the patient's samples obtained 2 and 9 days after transfusion of the Js(b+) RBCs to determine the potential clinical significance of the anti-Jsb. Various laboratory parameters including quantitative hemoglobin fraction analyses were used to monitor for increased RBC destruction. The MMA reactivity of the patient's anti-Jsb increased from 2.3 percent on day 2 after transfusion to strongly positive at 88 percent and 66.5 percent (with and without the addition of fresh serum) 1 week later. MMA reactivity of greater than 5 percent is associated with increased RBC destruction. There was no clinical or laboratory evidence of increased hemolysis above baseline. However, decreased RBC survival was suggested by the relatively brisk decrease of the HbA1 fraction after the transfusions. The current case and others reported in the literature suggest that anti-Jsb may have limited potential for causing overt hemolysis. However, in patients with underlying hematologic disease, even mildly increased RBC destruction may pose problems clinically,and thus transfusion of Js(b+) RBCs should be avoided. In emergent situations, the potential of adverse effects of transfusing incompatible units should be balanced against the risk of withholding transfusion. Family members, especially siblings, should be considered as potential designated donors for patients with antibodies directed against high-frequency antigens. Available reports on anti-Jsb in the literature are also reviewed.
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PMID:Transfusion of multiple units of Js(b+) red blood cells in the presence of anti-Jsb in a patient with sickle beta-thalassemia disease and a review of the literature. 1800 38


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