High titers of autoantibodies in patients with sickle-cell disease.

OBJECTIVE: Frequency and titers of autoantibodies in patients with sickle-cell disease (SCD) have been reported as relatively high. In a prospective study of 88 patients, we examined this "hyper-autoreactivity" and its clinical consequences. METHODS: For 1 year, patients with SCD were screened for the presence in their serum of antinuclear, anti-double-stranded DNA, antiextractible nuclear antigens, anticardiolipin antibodies, and rheumatoid factors. A population of 85 sex-matched individuals of similar ethnic origin served as controls. RESULTS: Whereas prevalence of autoantibodies did not differ between the 2 groups, the type and rate of antinuclear antibodies were different. Autoantibodies from the SCD patients showed various immunofluorescence patterns, whereas only speckled patterns at low titers were present in controls. No antibody specificity was found in either group. SCD patients and controls displayed similar rates of anticardiolipin antibodies, but the SCD patients tended to be more frequently positive for rheumatoid factors. Six-year followup of the SCD patients did not provide any clinical evidence for onset of an autoimmune disease, except for 1 patient who developed rheumatoid arthritis, with increasing antinuclear antibodies followed by emergence of specific markers 5 years later. CONCLUSION: Patients with SCD displayed high titers of autoantibodies. This observation may be due only to immune activation and/or dysfunction in SCD, as neither pathogenic specificity of autoantibodies nor autoimmune clinical signs appeared in the majority of cases in our study.

Complications and treatment of patients with ß-thalassemia in France: results of the National Registry.

BACKGROUND: beta-thalassemia is a rare disease in France, encountered mainly in patients originating from Italy and North Africa. In the setting of the recent French plan for rare diseases, a National Registry for thalassemia has been developed since 2005. Epidemiological and clinical data have been collected on living patients with beta-thalassemia major or intermedia, including those who underwent hematopoietic stem cell transplantation. DESIGN AND METHODS: A standardized questionnaire was sent to clinicians throughout the national professional networks involved in the management of thalassemic patients and data were updated every 18 months. A cross-sectional study was performed in February 2009. RESULTS: Data on 378 patients (267 with thalassemia major) with a median age of 20 were recorded. Hematopoietic stem cell transplantation was performed in 52 patients. Stature, rates of parenthood, splenectomy, and cholecystectomy were no different between non-transplanted thalassemia major and thalassemia intermedia patients, after adjustment for age. Among the 215 non-transplanted thalassemia major patients, the median serum ferritin level was 1240 ng/mL and the rates of iron-related complications were 10%, 6%, 10% and 48% for cardiac failure, diabetes, hypothyroidism, and hypogonadism, respectively. From 2005 to 2008, a dramatic switch in chelation treatment, from deferoxamine to deferasirox, was observed. CONCLUSIONS: The rates of complications of iron overload in French thalassemia major patients appeared similar to those reported in other developed countries in which this condition is not endemic. There were no significant differences in height and parenthood rates between patients with the major and the intermedia forms of the disease, underlining the progress in clinical care. Future developments will focus on mortality and morbidity under oral chelation treatment.

Treatment of chronic hepatitis C in sickle cell disease and thalassaemic patients with interferon and ribavirin.

BACKGROUND/AIM: Hepatic complications are a major cause of death in patients with congenital anaemia and chronic hepatitis C. Ribavirin is usually contraindicated in patients with haemolytic anaemia. This pilot study evaluated the efficacy and safety of antiviral treatment in patients with sickle cell disease (SCD) or beta-thalassaemia major (TM). METHODS: Eleven consecutive SCD and TM patients were included. Interferon monotherapy was administrated in the two first thalassaemic patients. Other patients received combination therapy with full dose of pegylated interferon 2b and increasing doses of ribavirin, starting with a low dose of ribavirin (400 mg/day). RESULTS: Hepatitis C virus genotypes were 1 or 4 in nine cases. A sustained virological response achieved in five of 11 patients despite unfavourable factors to response (genotypes, nonresponders to an earlier treatment). Haemoglobin level at the end of treatment was higher than baseline levels in five of six SCD patients. No SCD patient needed a transfusion during and after treatment period, neither presented vasoocclusive crisis. The mean increase in transfusion requirements was 32.5% in the thalassaemic group. CONCLUSION: A sustained virological response can be obtained in SCD and TM patients. No earlier study of excellent haematological tolerance among SCD patients under ribavirin has been reported to date. The results of this study suggest that full dose ribavirin could be used from the start of treatment in SCD patients.

Urinary endothelin-1 as a marker of renal damage in sickle cell disease.

BACKGROUND: Sickle cell disease (SCD) affects the kidney by acute mechanisms as well as by insidious renal medullary/papillary necrosis, resulting in tubular defects, which increase the risk of dehydration and subsequent sickle crisis. Hypoxia has been reported to stimulate endothelin-1 (ET-1) synthesis by endothelial cells and also in the renal tubule. METHODS: This case-control study measured ET-1 in urine as a marker of its renal synthesis in asymptomatic SCD patients. Baseline plasma and urinary ET-1 levels were measured and followed during a water deprivation study and a subsequent administration of desmopressin. RESULTS: Urine and plasma levels of ET-1 were elevated in patients with SCD, compared with carefully matched African-French and African controls, and urine ET-1 excretion was associated with a marked urine-concentrating defect. Moreover, urinary ET-1 output was correlated with microalbuminuria in SCD patients. CONCLUSIONS: ET-1 is known to antagonize the tubular effects of vasopressin and to promote renal scarring; increased renal production of ET-1 could produce nephrogenic diabetes insipidus and dehydration in SCD patients through a combination of fibrosis and functional resistance to vasopressin. This study provides a rationale for trials with endothelin receptor antagonists in sickle cell disease nephropathy.