Cardiovascular abnormalities in sickle cell disease

Sickle cell disease is characterized by recurrent episodes of ischemia-reperfusion injury to multiple vital organ systems and a chronic hemolytic anemia, both contributing to progressive organ dysfunction. The introduction of treatments that induce protective fetal hemoglobin and reduce infectious complications has greatly prolonged survival. However, with increased longevity, cardiovascular complications are increasingly evident, with the notable development of a progressive proliferative systemic vasculopathy, pulmonary hypertension (PH), and left ventricular diastolic dysfunction. Pulmonary hypertension is reported in autopsy studies, and numerous clinical studies have shown that increased pulmonary pressures are an important risk marker for mortality in these patients. In epidemiological studies, the development of PH is associated with intravascular hemolysis, cutaneous leg ulceration, renal insufficiency, iron overload, and liver dysfunction. Chronic anemia in sickle cell disease results in cardiac chamber dilation and a compensatory increase in left ventricular mass. This is often accompanied by left ventricular diastolic dysfunction that has also been a strong independent predictor of mortality in patients with sickle cell disease. Both PH and diastolic dysfunction are associated with marked abnormalities in exercise capacity in these patients. Sudden death is an increasingly recognized problem, and further cardiac investigations are necessary to recognize and treat high-risk patients.     

Pulmonary complications of sickle cell disease

Sickle cell disease (SCD) is a common monogenetic disorder with high associated morbidity and mortality. The pulmonary complications of SCD are of particular importance, as acute chest syndrome and pulmonary hypertension have the highest associated mortality rates within this population. This article reviews the pathophysiology, diagnosis, and treatment of clinically significant pulmonary manifestations of SCD, including acute chest syndrome, asthma, and pulmonary hypertension in adult and pediatric patients. Clinicians should be vigilant in screening and treating such comorbidities to improve patient outcomes.     

Pulmonary complications of sickle cell disease

The pulmonary complications of sickle cell disease are a major cause of morbidity and mortality in affected patients. The acute chest syndrome (ACS) is a leading cause of death in patients with sickle cell disease and has a multifactorial etiology. Hydroxyurea (HU), stem cell transplantation (SCT) and chronic transfusions are known to prevent the recurrence of ACS. Careful management of patients admitted for pain crises and surgery including use of incentive spirometry is critical in preventing this complication. Pulmonary hypertension is well known to be associated with sickle cell disease and patients with pulmonary hypertension have increased mortality. Asthma is also commonly seen in patients with sickle cell disease and is associated with a more complicated course. Chronic lung disease develops in a significant proportion of patients with sickle cell disease.     

Psychological complications in sickle cell disease

This review examines the evidence for some of the common psychological complications found across the life span of patients with sickle cell disease (SCD), which are likely to be encountered by haematologists responsible for their medical management. Electronic searches of medical and psychological databases were conducted with a focus on three main areas: psychological coping, quality of life and neuropsychology. Psychological complications were identified in both children and adults with SCD, and included inappropriate pain coping strategies; reduced quality of life owing to restrictions in daily functioning, anxiety and depression; and neurocognitive impairment. There were wide variations in design and consistency of the studies, therefore, some caution needs to be observed in the findings. Moreover, interventional studies were lacking in some areas such as neuropsychology. Utilization of psychological interventions including patient education, cognitive behavioural therapy, and special educational support to help improve the quality of life of patients are recommended.     

Standard management of sickle cell disease complications

Sickle cell disease remains a major public health concern in sub-Saharan Africa, Europe, and the United States. The survival rate of children and adolescents has increased immensely in developed countries, whereas the survival rate for adults lagged behind. The increase in the pediatric survival rate is attributable to the institution of hydroxyurea treatment as well as stroke prevention strategies. In this review, we discuss the management of the sickle disease major complications such as pain, stroke, and acute chest syndrome with the most current hydroxyurea use and transfusion therapy.     

Pulmonary complications in adult sickle cell disease

Sickle cell disease is an autosomal genetic condition which represents the most frequent genetic disease in ?le-de-France and Caribbean islands. The main clinical manifestations can be divided into infectious disease, hemolytic anemia and vaso-occlusive events. Pulmonary complications represent 20 to 30% of mortality due to sickle cell and can be divided into acute and chronic events. Acute chest syndrome (ACS) is an acute lung injury often preceded by a vaso-occlusive crisis and triggered by different factors including: hypoventilation, pulmonary infectious disease and vascular occlusions. These occlusions can be secondary to fat embolism, thrombosis or sickling. Treatment is mainly supportive combining oxygen supplementation adequate hydration analgesia and sedation. Exchange transfusion may be indicated in severe forms of ACS, characterized by a right ventricular dysfunction and acute respiratory failure. Pulmonary hypertension is the most serious chronic complication. Its frequency is estimated at 6% in adult patients and is more often described in patients with venous ulcers and higher levels of chronic hemolysis. Prognosis is poor with 12.5% of patients dying in the first two years following diagnosis irrespective of the actual pulmonary artery pressure level. There are currently limited data on the effects of any treatment modality. Other respiratory complications such as sleep disorders and nocturnal hypoxemia, infiltrative lung disease and exertional dyspnea are described and should be considered.     

Central venous catheter complications in sickle cell disease

A review of patients with sickle cell disease (SCD) and central venous catheters (CVCs) was performed to evaluate the frequency of catheter complications (infections, thrombotic events, and premature CVC removal. Fifteen evaluable patients were identified during our review of a 7.5-year period. The median age was 18 years (range, 1.5-30 years); 14 were African American, and 1 was Latino; 5 were male, and 10 were female. Forty-one CVCs were placed (36 Mediport and 5 Broviac catheters) for a total of 12,120 CVC days. We observed a median of 2 CVCs per patient (range, 1-8 CVCs per patient) with 67 discrete episodes of CVC-associated infection (range, 0-18 per patient) involving 10 patients. The rate of CVC-associated infection for patients with SCD at our institution was 5.5 infections per 1,000 CVC days; this rate was significantly higher than the rate of CVC-associated infection in our patients with cancer (P < 0.001). We also determined that the rate of CVC-associated thrombosis was 0.99 events per 1,000 CVC days and involved 33% of the patients with SCD; the rate of premature CVC removal was 3.15 per 1,000 CVC days, and 78% of CVCs were removed prematurely. We conclude that patients with SCD are at high risk for CVC-related complications, and improved care and close monitoring of CVCs should be encouraged to decrease morbidity in these chronically ill patients.     

l-selectin gene polymorphisms and complications of sickle cell disease

We had found high expression of L-selectin and alphaMbeta2 integrin on leukocytes in patients with complications of sickle cell disease (SCD). In non-SCD patients, L-selectin polymorphisms are associated with vasculopathy and nephropathy. Our objective was to determine if L-selectin gene polymorphisms affect leukocyte expression of the protein, or the development of complications in SCD. By polymerase chain reaction with sequence-specific primers incorporating mismatches at the 3'-end, we analysed DNA from 142 HbSS patients and 102 healthy, racially matched, HbAA controls; to detect the F206L, T49S, and P213S L-selectin gene polymorphisms. All patients were assessed for complications of SCD. Steady-state expression of L-selectin on leukocytes was measured by flow cytometry in 44 patients. We excluded HbSS patients on hydroxyurea, with any other disease, pregnancy, or HbF > or = 10%. There were no significant differences in distribution of F206L, T49S or P213S l-selectin gene polymorphisms between patients and controls (chi(2) = 0.1, P > 0.05). There was no association between any of these gene polymorphisms and high expression of L-selectin by leukocytes, or the development of complications in SCD (chi(2) = 2.37, P > 0.05). The findings suggest that these three gene polymorphisms do not predispose to high leukocyte expression of L-selectin, or development of complications in SCD.     

Oral and dental complications of sickle cell disease in Nigerians

A clinical evaluation of the oral and dental complications of sickle cell disease in Nigerians was carried out in 37 consecutive patients with homozygous sickle cell disease Hb-SS (Sicklers) compared to a control group of 24 persons with normal haemoglobin Hb-AA (control group) matched for age and sex. The significant abnormalities found in sicklers included intrinsic opacity of the teeth in 67.5% of sicklers compared to 28.83% in the control group; malocclusion of the teeth with over-jet and over-bite in 35% of sicklers compared to 16.66% in the control group; dental caries is present in 35.13% of sicklers which was less than its occurrence in 54% of the control group due to widespread avoidance of sweets by most local sicklers. Diastemata (gaps between the teeth) was present in approximately equal frequency in sicklers (27%) and control group (25%). In view of the aesthetic and medical implications of these abnormalities, it is recommended that sicklers should receive regular dental check-up with a view to ameliorating or preventing these complications by prophylactic measures including the use of orthodontic appliances such as braces, etc. The above findings are discussed in relation to the other complications of sickler cell disease in other organs of the body.     

Hemoglobin sickle cell disease complications: a clinical study of 179 cases

Background

Hemoglobin sickle cell disease is one of the most frequent hemoglobinopathies. Surprisingly, few studies have been dedicated to this disease, currently considered to be a mild variant of homozygous sickle cell disease. The aim of this study was to update our knowledge about hemoglobin sickle cell disease.

Design and Methods

The study involved a single center series of 179 patients. Clinical and biological data were collected with special attention to the assessment of pulmonary arterial hypertension and nephropathy.

Results

Hemoglobin sickle cell diagnosis was delayed and performed in adulthood in 29% of cases. Prevalence of hospitalized painful vasoocclusive crisis, acute chest syndrome and priapism was 36%, 20% and 20%, respectively. The most common chronic organ complications were retinopathy and sensorineural otological disorders in 70% and 29% of cases. Indeed, prevalence of complications reported in homozygous sickle cell disease, such as nephropathy, suspicion of pulmonary hypertension, strokes and leg ulcers was rather low (13%, 4% and 1%, respectively). Phlebotomy performed in 36% of this population (baseline hemoglobin 11.5 g/dL) prevented recurrence of acute events in 71% of cases.

Conclusions

Our data suggest that hemoglobin sickle cell disease should not be considered as a mild form of sickle cell anemia but as a separate disease with a special emphasis on viscosity-associated otological and ophthalmological disorders, and with a low prevalence of vasculopathy (strokes, pulmonary hypertension, ulcers and nephropathy). Phlebotomy was useful in reducing acute events and a wider use of this procedure should be further investigated.     

Cardiovascular complications of collagen vascular disease

Opinion statement  

ENERCA clinical recommendations for disease management and prevention of complications of sickle cell disease in children

Universal neonatal screening is performed in the United States, England, the Netherlands, and several cities in Belgium, with selective screening targeted on "high-risk" population in France (globally, one quarter of all the babies born in France are screened). Newborns diagnosed with a major sickle cell syndrome (SCD) should be referred to a designated pediatric sickle cell centre, and the parents are informed that their child has SCD; this may be in the sickle cell centre by an expert physician or in the community by an experienced nurse counsellor. The pediatric sickle cell centre should organize the care of the baby.     

Cardiopulmonary complications leading to premature deaths in adult patients with sickle cell disease

Sickle cell disease (SCD) is associated with early mortality. We sought to determine the incidence, cause, and risk factors for death in an adult population of patients with SCD. All patients aged ≥18 years seen at the Adult Sickle Cell Center at Duke University Medical Center between January 2000 and April 2005 were enrolled. Forty‐three patients (21 males and 22 females) died during the study period. The median age of survival was 39 years for females (95% CI: 34–56), 40 years for males (95% CI: 34–48), and 40 years overall (95% CI: 35–48). Cardiac causes of death accounted for 25.6% (11/43 patients); pulmonary, 14.0% (six patients); other SCD related, 32.6% (14 patients); unknown, 14.0% (six patients); and others, 14.0% (six patients). Pulseless electrical activity arrest, pulmonary emboli, multiorgan failure, and stroke were the most frequent causes of death. Among the deceased patients, the most common premorbid conditions were cardiopulmonary: acute chest syndrome/pneumonia (58.1%), Pulmonary hypertension (pHTN; 41.9%), systemic HTN (25.6%), congestive heart failure (25.6%), myocardial infarction (20.9%), and arrhythmias (14.0%). Tricuspid regurgitant jet velocity was significantly higher (3.1 m/sec vs. 2.6 m/sec, P < 0.001) and hemoglobin significantly lower (8.3 g/dL vs. 9.2 g/dL, P < 0.05) in deceased patients when compared with patients who lived, respectively. With improved preventive and therapeutic advances, including hydroxyurea therapy, acute complications such as infection are no longer the leading cause of death; instead, causes of death and premorbid conditions are shifting to chronic cardiopulmonary complications. Further, arrhythmia leading to premature death is under‐recognized in SCD and warrants further investigation. Am. J. Hematol., 2010. © 2009 Wiley‐Liss, Inc.     

Pathophysiology of sickle cell disease

Sickle cell disease is caused by a mutation in the beta-globin chain of the haemoglobin molecule. Sickle haemoglobin, the result of this mutation, has the singular property of polymerizing when deoxygenated. Exactly how normal tissue perfusion is interrupted by abnormal sickle cells is complex and poorly understood. Despite genetic identity at the site of the sickle haemoglobin mutation, all patients with sickle cell anaemia are not affected equally by this disease. Secondary genetic determinants and acquired erythrocyte and vascular damage are likely to be central components of the pathophysiology of sickle cell anaemia.     

Short-term central venous catheter complications in patients with sickle cell disease who undergo apheresis

Patients with sickle cell disease (SCD) are prone to develop thrombosis and infection due to their inflammatory and immune deficiency state. These patients require red cell exchange therapy for treatment or prevention of hemoglobin S associated complications. Owing to vascular access problems, adult patients need central venous catheterization (CVC) for exchange procedures. Procedure related complications have been reported for long-term CVCs in pediatric patients. However, short-term CVC complications in adult patients are not clear. This report represents the results of documented complications of short-term CVCs in patients with SCD who undergo apheresis. A total of 142 non-tunneled catheters with average median diameter of 9 F (range 8–16 F) were implanted for apheresis. The catheters were mainly inserted through the right internal jugular vein (66.2 %). Total days of catheter were 412. Results were reported as a complication rate and event according to 1,000 catheter days and compared to a control group including 37 healthy stem cell donors. In the patient group, 1 (1 %) hematoma and 1 (1 %) infection were observed for internal jugular vein catheterization (3.7 hemorrhages and 3.7 infections according to 1,000 catheter days), whereas four (8.9 %) cases of thrombosis and 1 (2.2 %) infection (27 and 6.9 according to 1,000 catheter days) developed in femoral vein. There was a significant difference in terms of thrombosis (P = 0.009). In the control group, only individual developed thrombosis in internal jugular vein. Short-term CVC inserted through to the internal jugular vein seems to be safer than femoral vein in patients with SCD.