James R. Eckman

Bone marrow transplantation for sickle cell disease

BACKGROUND We investigated the risks and benefits of allogeneic bone marrow transplantation in children with complications of sickle cell disease. METHODS Twenty-two children less than 16 years of age who had symptomatic sickle cell disease received marrow allografts from HLA-identical siblings between September 1991 and April 1995. The indications for transplantation included a history of stroke (n = 12), recurrent acute chest syndrome (n = 5), and recurrent painful crises (n = 5). Patients were prepared for transplantation with busulfan, cyclophosphamide, and antithymocyte globulin. RESULTS Twenty of the 22 patients survived, with a median follow-up of 23.9 months (range, 10.1 to 51.0), and 16 patients had stable engraftment of donor hematopoietic cells. In three patients the graft was rejected and sickle cell disease recurred; in a fourth patient graft rejection was accompanied by marrow aplasia. In 1 of the 16 patients with engraftment, there was stable mixed chimerism. Two patients died of central nervous system hemorrhage or graft-versus-host disease. Kaplan-Meier estimates of survival and event-free survival at four years were 91 percent and 73 percent, respectively. Among patients with a history of acute chest syndrome, lung function stabilized; among patients with prior central nervous system vasculopathy who had engraftment, stabilization of cerebrovascular disease was documented by magnetic resonance imaging. CONCLUSIONS Allogeneic stem-cell transplantation can be curative in young patients with symptomatic sickle cell disease.

A randomised comparison of deferasirox versus deferoxamine for the treatment of transfusional iron overload in sickle cell disease

Deferasirox is a once‐daily, oral iron chelator developed for treating transfusional iron overload. Preclinical studies indicated that the kidney was a potential target organ of toxicity. As patients with sickle cell disease often have abnormal baseline renal function, the primary objective of this randomised, open‐label, phase II trial was to evaluate the safety and tolerability of deferasirox in comparison with deferoxamine in this population. Assessment of efficacy, as measured by change in liver iron concentration (LIC) using biosusceptometry, was a secondary objective. A total of 195 adult and paediatric patients received deferasirox (n = 132) or deferoxamine (n = 63). Adverse events most commonly associated with deferasirox were mild, including transient nausea, vomiting, diarrhoea, abdominal pain and skin rash. Abnormal laboratory studies with deferasirox were occasionally associated with mild non‐progressive increases in serum creatinine and reversible elevations in liver function tests. Discontinuation rates from deferasirox (11·4%) and deferoxamine (11·1%) were similar. Over 1 year, similar dose‐dependent LIC reductions were observed with deferasirox and deferoxamine. Once‐daily oral deferasirox has acceptable tolerability and appears to have similar efficacy to deferoxamine in reducing iron burden in transfused patients with sickle cell disease.

Acute multiorgan failure syndrome: A potentially catastrophic complication of severe sickle cell pain episodes

The purpose of this report is to characterize the acute multiorgan failure syndrome that complicates some episodes of sickle pain. A retrospective chart review was used to identify episodes of sickle pain complicated by the acute failure of at least two of three organs: lung, liver, or kidney. The defining criteria of organ failure were established, and the clinical characteristics, laboratory values, treatment methods, and outcomes were noted in episodes that met the criteria. Seventeen episodes of acute multiorgan failure were identified in 14 patients, 10 with sickle cell anemia and 4 with hemoglobin SC disease. Most episodes occurred during a pain event that was unusually severe for the patient. The onset of organ failure was associated with fever, rapid fall in hemoglobin level and platelet count, nonfocal encephalopathy, and rhabdomyolysis. Bacterial cultures were negative in all but four episodes. Aggressive transfusion therapy was associated with survival and with rapid recovery of organ function in all but one episode. The syndrome developed in patients who had previously exhibited relatively mild disease with little evidence of chronic organ damage and relatively high hemoglobin values in steady state. Acute multiorgan failure syndrome is a severe, life-threatening complication of pain episodes in patients with otherwise mild sickle cell disease. The syndrome appears to be reversed with prompt, aggressive transfusion therapy. High baseline hemoglobin levels may represent a predisposing factor.

The perioperative complication rate of orthopedic surgery in sickle cell disease: Report of the national sickle cell surgery study group

Orthopedic disease affects the majority of sickle cell anemia patients of which aseptic necrosis of the hip is the most common, occurring in up to 50% of patients. We conducted a multicentered study to determine the perioperative complications among sickle cell patients assigned to different transfusion regimens prior to orthopedic procedures: 118 patients underwent 138 surgeries. The overall serious complication rate was 67%. The most common of these were excessive intraoperative blood loss, defined as in excess of 10% of blood volume. The next most common complication was sickle cell‐related events (acute chest syndrome or vaso‐occlusive crisis), which occurred in 17% of cases. While preoperative transfusion group assignment did not predict overall complication rates, higher risk procedures were associated with significantly higher rates of overall complications. Transfusion complications were experienced by 12% of the patients. Two patients died following surgery. Both deaths were associated with an acute pulmonary event. The 52 patients undergoing hip replacements experienced the highest rate of complications with excessive intraoperative blood loss occurring in the majority of patients. Sickle cell‐related events occurred in 19% of patients, and surgical complications occurred after 15% of hip replacements and included postoperative hemorrhage, dislocated prosthesis, wound abscess, and rupture of the femoral prosthesis. There were twenty‐two hip coring procedures. Acute chest syndrome occurred in 14% of the patients. Overall, decompression coring was a safer, shorter operation. A randomized prospective trial to determine the perioperative and long‐term efficacy of core decompression for avascular necrosis of the hip in sickle cell disease is needed. In conclusion, this study demonstrates a high rate of perioperative complications despite compliance with sickle cell perioperative care guidelines. Pulmonary complications and transfusion reactions were common. This study supports the results previously published by the National Preoperative Transfusion in Sickle Cell Disease Group. These results stated that a conservative preoperative transfusion regimen to bring hemoglobin concentration to between 9 and 11 g/dl was as effective as an aggressive transfusion regimen in which the hemoglobin S level was lowered to 30%. Am. J. Hematol. 62:129–138, 1999.

Invasive pneumococcal infections in children with sickle cell disease in the era of penicillin prophylaxis, antibiotic resistance, and 23-valent pneumococcal polysaccharide vaccination

Rates and severity of pneumococcal infections in children with sickle cell disease were examined before licensure of pneumococcal-conjugated vaccine (PVC). Rates of peak invasive infection rates in 1-year-old children with hemoglobin SS and mortality in those 0 to 10 years of age were 36.5 to 63.4 and 1.4 to 2.8 per 1000 person-years, respectively (>10 and 100 times as frequent as in the general population). Overall, 71% of serotyped isolates (n=80) were PVC serotypes and 71% of nonvaccine serotype strains were penicillin-sensitive. Clinical presentation in children with hemoglobin SS (n=71; more with hypotension) and hemoglobin SC (n=18; more with acute chest syndrome, otitis media) differed. Penicillin nonsusceptibility (38% of isolates) varied between geographic study sites. Penicillin prophylaxis appeared less effective against intermediate and resistant strains. Of all infected children, meningitis developed in 20% and 15% died (hemoglobin SS, n=15 and 11; hemoglobin SC, n=1 each). Factors associated with death included age >4 years (58%), serotype 19F, and not being followed by a hematologist (42% each). The pneumococcal-polysaccharide vaccine was 80.4% effective within 3 years after vaccination (95% CI, 39.7, 93.6). Children with sickle cell disease of all ages may benefit from PVC boosted with polysaccharide vaccination.

Factors associated with survival in a contemporary adult sickle cell disease cohort.

In this study, the relationship of clinical differences among patients with sickle cell disease (SCD) was examined to understand the major contributors to early mortality in a contemporary cohort. Survival data were obtained for 542 adult subjects who were enrolled since 2002 at three university hospitals in the southeast United States. Subjects were followed up for a median of 9.3 years. At enrollment, clinical parameters were collected, including hemoglobin (Hb) genotype, baseline laboratory values, comorbidities, and medication usage. Levels of soluble adhesion molecules were measured for a subset of 87 subjects. The relationship of clinical characteristics to survival was determined using regression analysis. Median age at enrollment was 32 years. Median survival was 61 years for all subjects. Median survival for Hb SS and Sβ0 was 58 years and for Hb SC and Sβ+ was 66 years. Elevated white blood count, lower estimated glomerular filtration rate, proteinuria, frequency of pain crises, pulmonary hypertension, cerebrovascular events, seizures, stroke, sVCAM‐1, and short‐acting narcotics use were significantly associated with decreased survival. Forty‐two percent of subjects were on hydroxyurea therapy, which was not associated with survival. SCD continues to reduce life expectancy for affected individuals, particularly those with Hb Sβ0 and SS. Not only were comorbidities individually associated with decreased survival but also an additive effect was observed, thus, those with a greater number of negative endpoints had worse survival (P < 0.0001). The association of higher sVCAM‐1 levels with decreased survival suggests that targeted therapies to reduce endothelial damage and inflammation may also be beneficial. Am. J. Hematol. 89:530–535, 2014.

Hydroxyurea and sickle cell anemia: Effect on quality of life

BackgroundThe Multicenter Study of Hydroxyurea (HU) in Sickle Cell Anemia (MSH) previously showed that daily oral HU reduces painful sickle cell (SS) crises by 50% in patients with moderate to severe disease. The morbidity associated with this disease is known to have serious negative impact on the overall quality of life(QOL) of affected individuals.MethodsThe data in this report were collected from the 299 patients enrolled in the MSH. Health quality of llife (HQOL) measures were assessed in the MSH as a secondary endpoint to determine if the clinical benefit of HU could translate into a measurable benefit perceptible to the patients. HQOL was assessed with the Profile of Mood States, the Health Status Short Form 36 (SF-36), including 4-week pain recall, and the Ladder of Life, self-administered twice 2-weeks apart pre-treatment and every 6 months during the two-year, randomized, double-blind, treatment phase. The effects of factors including randomized treatment, age, gender, pre-treatment crises frequency, Hb-F level mean, daily pain from 4-week pre-treatment diaries, and 2-year Hb-F response level (low or high) were investigated.ResultsOver two years of treatment, the benefit of HU treatment on QOL, other than pain scales, was limited to those patients taking HU who maintained a high HbF response, compared to those with low HbF response or on placebo. These restricted benefits occurred in social function, pain recall and general health perception. Stratification according to average daily pain prior to treatment showed that responders to HU whose average daily pain score was 5–9 (substantial pain) achieved significant reduction in the tension scale compared to the placebo group and to non-responders. HU had no apparent effect on other QOL measures.ConclusionTreatment of SS with HU improves some aspects of QOL in adult patients who already suffer from moderate-to-severe SS.

Leg ulcers in sickle cell disease.

Sickle cell disease is a single amino acid molecular disorder of hemoglobin leading to its pathological polymerization, red cell rigidity that causes poor microvascular blood flow, with consequent tissue ischemia and infarction. The manifestations of this disease are protean.Among them, leg ulcers represent a particularly disabling and chronic complication, often associated with a more severe clinical course.Despite the fact that this complication has been recognized since the early times of SCD, there has been little improvement in the efficacy of its management and clinical outcome over the past 100 years. Recently, vasculopathic abnormalities involving abnormal vascular tone and activated, adhesive endothelium have been recognized as another pathway to end organ damage in sickle cell disease. Vasculopathy of sickle cell disease has been implicated in the development of pulmonary hypertension, stroke, leg ulceration and priapism, particularly associated with hemolytic severity, and reported in other severe hemolytic disorders. The authors present the proceedings from the Educational Session on Chronic leg ulcers in Sickle cell disease, held during the 4th Annual Sickle Cell Disease Research and Educational Symposium, on February 17, 2010 in Fort Lauderdale, Fla.

Psychosocial and Family Functioning in Children with Sickle Cell Syndrome and Their Mothers

OBJECTIVE The purpose of this study was to compare the psychiatric functioning of 61 sickle cell youth and their families with nondiseased sibling controls. METHOD Functioning assessed by multiple informants included indices of behavioral, cognitive, and family/interpersonal functioning, self-esteem, life events, coping strategies, temperament, adaptive behavior, and parental psychopathology. RESULTS Key findings were that sickle cell patients evidenced more depressive symptoms and associated attributional style, and externalizing behavioral difficulties than did nondiseased siblings. With age, sickle cell youth evidence increasing adaptive behavior deficits and internalizing symptoms. Illness severity was related to symptoms of internalizing behavior and fewer daily living skills. Associations were found between maternal and child coping. CONCLUSIONS It is recommended that psychiatric consultations routinely be conducted with these children, particularly at times of family stress and developmental transitions. Psychiatric interventions should focus on ameliorating emotional difficulties via enhancing adaptive coping strategies.

MYH9 and APOL1 are both associated with sickle cell disease nephropathy

Renal failure occurs in 5–18% of sickle cell disease (SCD) patients and is associated with early mortality. At‐risk SCD patients cannot be identified prior to the appearance of proteinuria and the pathobiology is not well understood. The myosin, heavy chain 9, non‐muscle (MYH9) and apolipoprotein L1 (APOL1) genes have been associated with risk for focal segmental glomerulosclerosis and end‐stage renal disease in African Americans. We genotyped 26 single nucleotide polymorphisms (SNPs) in MYH9 and 2 SNPs in APOL1 (representing the G1 and G2 tags) in 521 unrelated adult (18–83 years) SCD patients screened for proteinuria. Using logistic regression, SNPs were evaluated for association with proteinuria. Seven SNPs in MYH9 and one in APOL1 remained significantly associated with proteinuria after multiple testing correction (P < 0·0025). An MYH9 risk haplotype (P = 0·001) and the APOL1 G1/G2 recessive model (P < 0·0001) were strongly associated with proteinuria, even when accounting for the other. Glomerular filtration rate was negatively correlated with proteinuria (P < 0·0001), and was significantly predicted by an interaction between MYH9 and APOL1 in age‐adjusted analyses. Our data provide insight into the pathobiology of renal dysfunction in SCD, suggesting that MYH9 and APOL1 are both associated with risk.