The presentation, management and prophylaxis of sickle cell disease

Penicillin V prophylaxis uptake among children living with sickle cell disease in a specialist sickle cell clinic in Ghana: A cross-sectional study

Background and Aims

Penicillin V prophylaxis protects children living with sickle cell disease (SCD) from bacteria infections especially Streptococcus pneumonia. However, the uptake of penicillin V prophylaxis is difficult to assess and often poor among SCD patients. Therefore, this study sought to investigate oral penicillin V prophylaxis adherence among SCD children using urine assay and self-reported methods and the associated factors.

Methods

The study employed an analytical cross-sectional design in the assessment of penicillin V prophylaxis adherence using both urine assay and self-reported methods. Multiple logistic regression analysis was used to determine the factors associated with penicillin V prophylaxis adherence. A p value < 0.05 was considered statistically significant.

Results

Among the 421 SCD patients recruited, penicillin V prophylaxis adherence was observed to be 30.0% and 68.0% for the objective and subjective methods of assessment, respectively. For the objective method of assessment, being cared for by grandparents increased the odds of penicillin V adherence (adjusted odds ratio [aOR] = 3.68, confidence interval [CI] = 1.03-13.15). However, SCD patients within the ages of 10-14 years (aOR = 0.36, CI = 0.17-0.80), >14 years (aOR = 0.17, CI = 0.05-0.61), SCD patient cared for by married caregivers/parents (aOR = 0.32, CI = 0.14-0.72), SCD patient cared for by divorced caregivers/parents (aOR = 0.23, CI = 0.07-0.75), SCD patients taking homemade (herbal) preparations for the treatment of SCD (aOR = 0.42, CI = 0.21-0.83), and inappropriate intake of penicillin V prophylaxis (aOR = 0.27, CI = 0.11-0.67) reduced the odds of penicillin V adherence. For the subjective method of assessment, taking homemade preparation (herbal) for the treatment of SCD (aOR = 0.52, CI = 0.30-0.89) and inappropriate intake of penicillin V (aOR = 0.32, CI = 0.17-0.60) reduced the odds of penicillin V adherence.

Conclusion

This study reports a relatively low adherence rate of penicillin V prophylaxis among children living with SCD. Educating and counseling both SCD patients and/or caregivers on the need to be adherent to penicillin V prophylaxis could prevent complications that may arise from nonadherence.

Plasma Concentration of 12-Hydroxyeicosatetraenoic Acid, Single Nucleotide Polymorphisms of 12-Lipooxygenase Gene and Vaso-Occlusion in Sickle Cell Disease

Background and Novel Aspect of this Work: In the light of previous findings that inflammation predisposes to intercellular adhesion and microvascular occlusion in sickle cell disease (SCD), this study investigated the relationship between the number of vaso-occlusive events in SCD, plasma levels of the pro-inflammatory molecules 12-Hydroxyeicosatetraenoic acid (12-HETE), TNF-α and IL-1β; and single nucleotide polymorphisms (SNPs) in the gene 12-Lipooxygenase (ALOX-12), which encodes the enzyme 12-Lipoxygenase that catalyzes the biosynthesis of 12-HETE.

Objective: To evaluate the relationship between vaso-occlusion in SCD and plasma concentrations of 12-HETE, TNF-α, and IL-1β; and single nucleotide polymorphisms (SNPs) in ALOX-12 gene.

Participants and Methods: In 50 HbSS patients, the numbers of vaso-occlusive crisis requiring hospital treatment in the previous 1 year and the vaso-occlusive complications of SCD developed to date (e.g stroke) were added to obtain the vaso-occlusive events (VOE) score. In the HbSS patients and 30 healthy sibling control persons, plasma concentrations of 12-HETE, TNF-α and IL-1β were measured by ELISA, the ALOX12 SNPs rs2073438 and rs1126667 detected by DNA sequencing, and the accrued data statistically analyzed.

Results: Compared to SCD patients with VOE score 0–1, those with scores ≥3 had higher plasma levels of 12-HETE (p < 0.0001) and TNF-α (p = 0.19), but not IL-1β (p = 0.27). VOE score showed strong direct correlation with plasma level of 12-HETE (r = 0.65, p < 0.0001), but not with TNF-α nor IL-1β. Neither VOE score nor plasma concentration of 12-HETE showed any relationship with the ALOX12 SNPs rs2073438 and rs1126667.

Conclusion: The strong direct correlation of VOE score with plasma concentration of 12-HETE suggests that the clinical relevance of this pro-inflammatory molecule in SCD-associated vaso-occlusion needs to be evaluated in further studies.

Life-Threatening Infectious Complications in Sickle Cell Disease: A Concise Narrative Review

Sickle cell disease (SCD) results in chronic hemolytic anemia, recurrent vascular occlusion, insidious vital organ deterioration, early mortality, and diminished quality of life. Life-threatening acute physiologic crises may occur on a background of progressive diminishing vital organ function. Sickle hemoglobin polymerizes in the deoxygenated state, resulting in erythrocyte membrane deformation, vascular occlusion, and hemolysis. Vascular occlusion and increased blood viscosity results in functional asplenia and immune deficiency in early childhood, resulting in life-long increased susceptibility to serious bacterial infections. Infection remains a main cause of overall mortality in patients with SCD in low- and middle-income countries due to increased exposure to pathogens, increased co-morbidities such as malnutrition, lower vaccination rates, and diminished access to definitive care, including antibiotics and blood. Thus, the greatest gains in preventing infection-associated mortality can be achieved by addressing these factors for SCD patients in austere environments. In contrast, in high-income countries, perinatal diagnosis of SCD, antimicrobial prophylaxis, vaccination, aggressive use of antibiotics for febrile episodes, and the availability of contemporary critical care resources have resulted in a significant reduction in deaths from infection; however, chronic organ injury is problematic. All clinicians, regardless of their discipline, who assume the care of SCD patients must understand the importance of infectious disease as a contributor to death and disability. In this concise narrative review, we summarize the data that describes the importance of infectious diseases as a contributor to death and disability in SCD and discuss pathophysiology, prevalent organisms, prevention, management of acute episodes of critical illness, and ongoing care.

The past, present and future management of sickle cell retinopathy within an African context

Sickle cell retinopathy is a potentially blinding condition that affects young people in the working age group. This review looks at the past, present and future management of sickle cell retinopathy within an African context. After Sickle cell disease was first reported in 1910, some reports from Africa were pivotal in describing the retinal changes associated with the disease. It soon became obvious that there was a varied clinical picture and clinical course. Several landmark studies were carried out in Jamaica to help elucidate the complexities of the disease and outline appropriate clinical management. In most of the developed world, the clinical management of sickle cell disease has improved with concurrent improvement in outcomes. Currently resource constraints in most Sub-Saharan African countries where there is a high burden of disease means that the management of sickle cell retinopathy is fraught with numerous challenges. Future large scale trials in Africa shall hopefully help to better elucidate the mechanisms behind proliferative sickle retinopathy and help in the development of new and improved therapeutic pathways. The use of technology can help immensely in the screening of patients with sickle cell to detect early proliferative changes and if necessary treat accordingly.

Splenectomy versus conservative management for acute sequestration crises in people with sickle cell disease

BACKGROUND

Acute splenic sequestration crises are a complication of sickle cell disease, with high mortality rates and frequent recurrence in survivors of first attacks. Splenectomy and blood transfusion, with their consequences, are the mainstay of long-term management used in different parts of the world. This is a 2017 update of a Cochrane Review first published in 2002, and previously updated, most recently in 2015.

OBJECTIVES

To assess whether splenectomy (total or partial), to prevent acute splenic sequestration crises in people with sickle cell disease, improved survival and decreased morbidity in people with sickle cell disease, as compared with regular blood transfusions.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Haemoglobinopathies Trials Register, which comprises of references identified from comprehensive electronic database searches and handsearching relevant journals and abstract books of conference proceedings. We also searched clinical trial registries. Additional trials were sought from the reference lists of the trials and reviews identified by the search strategy.Date of the most recent search: 14 August 2017.

SELECTION CRITERIA

All randomized or quasi-randomized controlled trials comparing splenectomy (total or partial) to prevent recurrence of acute splenic sequestration crises with no treatment or blood transfusions in people with sickle cell disease.

DATA COLLECTION AND ANALYSIS

No trials of splenectomy for acute splenic sequestration were found.

MAIN RESULTS

No trials of splenectomy for acute splenic sequestration were found.

AUTHORS' CONCLUSIONS

Splenectomy, if full, will prevent further sequestration and if partial, may reduce the recurrence of acute splenic sequestration crises. However, there is a lack of evidence from trials showing that splenectomy improves survival and decreases morbidity in people with sickle cell disease. There is a need for a well-designed, adequately-powered, randomized controlled trial to assess the benefits and risks of splenectomy compared to transfusion programmes, as a means of improving survival and decreasing mortality from acute splenic sequestration in people with sickle cell disease.There are no trials included in the review and we have not identified any relevant trials up to August 2017. We will continue to run searches to identify any potentially relevant trials; however, we do not plan to update other sections of the review until new trials are published.

Pattern and prevelence of alloimmunization in multiply transfused patients with sickle cell disease in Nigeria

BACKGROUND AND STUDY OBJECTIVES

Blood transfusion is central in the prevention and treatment of certain chronic complications of sickle cell disease. It is indispensible in correcting anaemias as well as in the practice of exchange blood transfusion. These gains are largely limited by formation of allo-antibodies. Several studies demonstrated varying frequencies of allo-immunization in various patient groups. The effect of the racial differences between the donor and recipient pool, which has been subsumed in this study, has continuously created a confounding effect on the results of previous studies.

AIM

This study was aimed at determining the pattern and frequency of allo-immunization in multiply transfused sickle cell patients, in a racially matched donor and recipient population.

PATIENTS AND METHODS

This was a cross-sectional case-controlled study involving 80 Nigerian sickle cell disease patients who had received three or more units of packed red cells in the within 4 weeks of the study and 40 controls (who were SCD that had not been transfused in their life time). Antibody screening and identification was done using the Diamed microtyping system.

RESULTS

Frequency of allo-immunization was determined to be 18.7 % (15/80) among the previously transfused and 5 % (15/120) in all sickle cell disease patients. Auto-antibodies were detected in 1.25 % of the study group and 2.5 % of the control, and all reacted with the Kell and Lutheran blood group antigens. The pattern of allo-antibodies found showed; 46.7 % Rhesus, 40 % Kell, while Lutheran and Duffy 13.3 %, each.

CONCLUSION

Sickle cell disease patients are particularly susceptible to development of allo-antibodies despite racial similarities between the donor and recipient population. The most common allo-antibodies are Rhesus, Kell and Lutheran and Duffy respectively in order of decreasing frequency. Development of auto-antibodies seems to be independent of blood transfusion in sickle cell disease with possibly different pathogenetic mechanism. Policy on extended red cell phenotyping for common antigens will reduce allo-immunization among multiply transfused patients.

Splenectomy versus conservative management for acute sequestration crises in people with sickle cell disease

BACKGROUND

Acute splenic sequestration crises are a complication of sickle cell disease, with high mortality rates and frequent recurrence in survivors of first attacks. Splenectomy and blood transfusion, with their consequences, are the mainstay of long-term management used in different parts of the world. This is a 2015 update of a Cochrane review first published in 2002, and previously updated in 2013.

OBJECTIVES

To assess whether splenectomy (total or partial), to prevent acute splenic sequestration crises in people with sickle cell disease, improved survival and decreased morbidity in people with sickle cell disease, as compared with regular blood transfusions.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Haemoglobinopathies Trials Register, which comprises of references identified from comprehensive electronic database searches and handsearching relevant journals and abstract books of conference proceedings.Additional trials were sought from the reference lists of the trials and reviews identified by the search strategy.Date of the most recent search: 10 June 2015.

SELECTION CRITERIA

All randomized or quasi-randomized controlled trials comparing splenectomy (total or partial) to prevent recurrence of acute splenic sequestration crises with no treatment or blood transfusions in people with sickle cell disease.

DATA COLLECTION AND ANALYSIS

No trials of splenectomy for acute splenic sequestration were found.

MAIN RESULTS

No trials of splenectomy for acute splenic sequestration were found.

AUTHORS' CONCLUSIONS

Splenectomy, if full, will prevent further sequestration and if partial, may reduce the recurrence of acute splenic sequestration crises. However, there is a lack of evidence from trials showing that splenectomy improves survival and decreases morbidity in people with sickle cell disease. There is a need for a well-designed, adequately-powered, randomized controlled trial to assess the benefits and risks of splenectomy compared to transfusion programmes, as a means of improving survival and decreasing mortality from acute splenic sequestration in people with sickle cell disease.There are no trials included in the review and we have not identified any relevant trials up to June 2015. We will continue to run searches to identify any potentially relevant trals; however, we do not plan to update other sections of the review until new trials are published.

Hydroxyurea in Sickle Cell Disease: Our Experience in Western India

Sickle cell disease (SCD) is common in tribal belt of Gujarat, but not addressed effectively as it should be with effective use of Hydroxyurea, supportive care and counseling. In our single centre study of 70 patients of SCD who were only on Folic acid and Blood transfusion support, were analyzed and followed up for 1 year in terms of their clinical symptoms, Blood transfusion requirement, laboratory parameters before and after Hydroxyurea therapy. We found statistically significant improvement in clinical symptoms and positive changes in laboratory parameters studied. This validates the well established role of Hydroxyurea in SCD as seen in the various international trials. Hence it is imperative that the well documented benefits of Hydroxyurea in various International studies should be translated into clinical practice. SCD should be treated like a chronic disorder needing preventive therapy in form of Hydroxyurea and counseling with regular follow up.

Management of sickle cell disease: a review for physician education in Nigeria (sub-saharan Africa)

Sickle cell disease (SCD) predominates in sub-Saharan Africa, East Mediterranean areas, Middle East, and India. Nigeria, being the most populous black nation in the world, bears its greatest burden in sub-Saharan Africa. The last few decades have witnessed remarkable scientific progress in the understanding of the complex pathophysiology of the disease. Improved clinical insights have heralded development and establishment of disease modifying interventions such as chronic blood transfusions, hydroxyurea therapy, and haemopoietic stem cell transplantation. Coupled with parallel improvements in general supportive, symptomatic, and preventive measures, current evidence reveals remarkable appreciation in quality of life among affected individuals in developed nations. Currently, in Nigeria and other West African states, treatment and control of SCD are largely suboptimal. Improved knowledge regarding SCD phenotypes and its comprehensive care among Nigerian physicians will enhance quality of care for affected persons. This paper therefore provides a review on the aetiopathogenesis, clinical manifestations, and management of SCD in Nigeria, with a focus on its local patterns and peculiarities. Established treatment guidelines as appropriate in the Nigerian setting are proffered, as well as recommendations for improving care of affected persons.

Splenectomy versus conservative management for acute sequestration crises in people with sickle cell disease

BACKGROUND

Acute splenic sequestration crises are a complication of sickle cell disease, with high mortality rates and frequent recurrence in survivors of first attacks. Splenectomy and blood transfusion, with their consequences, are the mainstay of long-term management used in different parts of the world.

OBJECTIVES

To assess whether splenectomy (total or partial), to prevent acute splenic sequestration crises in people with sickle cell disease, improved survival and decreased morbidity in people with sickle cell disease, as compared with regular blood transfusions.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Haemoglobinopathies Trials Register, which comprises of references identified from comprehensive electronic database searches and handsearching relevant journals and abstract books of conference proceedings.Additional trials were sought from the reference lists of the trials and reviews identified by the search strategy.Date of the most recent search: 06 December 2012.

SELECTION CRITERIA

All randomized or quasi-randomized controlled trials comparing splenectomy (total or partial) to prevent recurrence of acute splenic sequestration crises with no treatment or blood transfusions in people with sickle cell disease.

DATA COLLECTION AND ANALYSIS

No trials of splenectomy for acute splenic sequestration were found.

MAIN RESULTS

No trials of splenectomy for acute splenic sequestration were found.

AUTHORS' CONCLUSIONS

Splenectomy, if full, will prevent further sequestration and if partial, may reduce the recurrence of acute splenic sequestration crises. However, there is a lack of evidence from trials showing that splenectomy improves survival and decreases morbidity in people with sickle cell disease. There is a need for a well-designed, adequately-powered, randomized controlled trial to assess the benefits and risks of splenectomy compared to transfusion programmes, as a means of improving survival and decreasing mortality from acute splenic sequestration in people with sickle cell disease.

Beyond the definitions of the phenotypic complications of sickle cell disease: an update on management

The sickle hemoglobin is an abnormal hemoglobin due to point mutation (GAG → GTG) in exon 1 of the β globin gene resulting in the substitution of glutamic acid by valine at position 6 of the β globin polypeptide chain. Although the molecular lesion is a single-point mutation, the sickle gene is pleiotropic in nature causing multiple phenotypic expressions that constitute the various complications of sickle cell disease in general and sickle cell anemia in particular. The disease itself is chronic in nature but many of its complications are acute such as the recurrent acute painful crises (its hallmark), acute chest syndrome, and priapism. These complications vary considerably among patients, in the same patient with time, among countries and with age and sex. To date, there is no well-established consensus among providers on the management of the complications of sickle cell disease due in part to lack of evidence and in part to differences in the experience of providers. It is the aim of this paper to review available current approaches to manage the major complications of sickle cell disease. We hope that this will establish another preliminary forum among providers that may eventually lead the way to better outcomes.

Serum testosterone levels of HbSS (sickle cell disease) male subjects in Lagos, Nigeria

BACKGROUND

Infertility is a major problem in sickle cell disease patients, especially in males. In addition to low serum testosterone, other abnormalities involving the accessory sex organs, such as the seminal vesicles and the prostate gland, as well as marked decrease in ejaculate volume may be observed in male HbSS patients. Hence, the need to study the role of sex hormones as a cause of infertility in male HbSS patients.

METHODS

An unmatched case-control study was performed using seventy-five consenting subjects from Lagos University Teaching Hospital. These included 47 patients with haemoglobin phenotype SS from the Sickle cell clinic and 28 volunteered medical students and members of staff with haemoglobin phenotype AA. Demographic data were obtained using a self-administered questionnaire. A total of 5 mls of blood was collected from each subject between 9.00 am & 11.am, and assayed for serum testosterone concentration.

RESULTS

The concentrations of serum testosterone in HbSS patients ranged from 0.2 to 4.3 ng/ml with a mean of 1.28 ± 0.72 ng/ml whilst the values in HbAA controls ranged from 1.2 to 6.9 ng/ml with a mean of 2.63 ± 1.04 ng/ml. Seven (25.0%) of the 28 controls had serum testosterone concentration lower than the quoted reference (normal) range whereas 44 (93.6%) of the 47 HbSS subjects had serum testosterone concentration lower than the reference range.

CONCLUSION

Overall, subjects with HbSS have significantly lower mean serum testosterone than HbAA controls.

Can new optical techniques for in vivo imaging and flow cytometry of the microcirculation benefit sickle cell disease research?

Intravital microscopy is a valuable tool for research into sickle cell disease with studies being carried out on transgenic mice and human volunteers. The method has helped to develop an explanation for sickle crises based on cell adhesion to the vascular endothelium followed by logjamming of rigid sickle cells and has stimulated much research into new treatments. In recent years there have been numerous new optical techniques developed for imaging the microcirculation and understanding the circulation of cells within the body, many of which have been further developed into in vivo flow cytometry techniques. This brief review highlights some of the progress made to date in the understanding of sickle cell disease using intravital microscopy. New techniques for imaging the microcirculation and their potential uses in understanding sickle cell disease are discussed.

Increased risk of invasive bacterial infections in African people with sickle-cell disease: a systematic review and meta-analysis

Children with sickle-cell disease are at great risk of serious infections and early mortality. Our Review investigates the association between sickle-cell disease and invasive bacterial disease among populations in Africa. We systematically searched published work extracted data on pneumonia, meningitis, and bacteraemia by sickle-cell disease status. Most studies identified lacked a control group and did not use best laboratory methods for culturing fastidious bacteria. Only seven case-control or case-cohort studies provided data on the association between invasive bacterial disease and sickle-cell disease status. For all-cause laboratory-confirmed invasive bacterial disease, the pooled odds of sickle-cell disease was 19-times greater among cases than controls. For disease caused by Streptococcus pneumoniae, the pooled odds of sickle-cell disease was 36-times greater; and for Haemophilus influenzae type b disease it was 13-times greater.

Penicillin Prophylaxis in Children with Sickle Cell Disease

Children who have sickle cell disease and are under the age of five years are at increased risk of life-threatening pneumococcal infection due to absent or non-functional spleens and a decreased immune response. To prevent pneumococcal infection, the American Academy of Pediatrics recommends the use of penicillin prophylaxis in children with sickle cell disease under the age of five and in older children who have had a previous severe pneumococcal infection or have functional/surgical asplenia. These recommendations are based on two landmark studies, the first evaluating the effectiveness of penicillin prophylaxis and the second evaluating the duration of prophylaxis. Although the mortality rate from infection has been reduced following penicillin prophylaxis, altered immunologic response and penicillin-resistant S. pneumoniae remain a concern. This paper will review the literature that supports the use of penicillin prophylaxis, potential problems associated with prolonged therapy and recommendations for prophylaxis.

Impact of an Emergency Department Pain Management Protocol on the Pattern of Visits by Patients with Sickle Cell Disease

This study explores how implementation of pain management guidelines in concert with clinic case management affected emergency department (ED) utilization, clinic visits, and hospital admissions for patients with sickle cell disease. A pain management guideline that eliminated meperidine and encouraged timely use of morphine or hydromorphone for pain control in sickle cell crisis was introduced as a quality improvement project. This study is a retrospective review of ED visits, clinic visits, and admissions from 1 year before and 3 years after the guideline implementation. Working with the ED, the Hematology Clinic began to proactively seek the return of their patients for clinic follow-up. A formal case management program for sickle cell patients was initiated in June 2003. A total of 1584 visits by 223 patients were collected, 1097 to the ED and 487 to the Hematology Clinic. Total hospital visits did not change significantly in any of the 4 years, p > 0.10 for each comparison. Total ED visits decreased significantly over the 4-year study period (p < 0.001), whereas clinic visits steadily increased (p < 0.001). Return visits to the ED within 30 days also declined significantly, p < 0.001. Both the absolute number of admissions per year and the total admissions per hospital visit per year declined significantly over the study period, p = 0.001. Although total admissions per hospital visit did not change, the proportion of ED visits that resulted in admission in year 1 (29%) was significantly lower than the proportion admitted in year 2 (43%), p = 0.04. A pain protocol using morphine or hydromorphone coupled with increased access to outpatient clinics decreased ED visits, hospitalizations, and increased utilization of a more stable primary care clinic setting by patients with sickle cell disease.

Granulocytic adhesive interactions and their role in sickle cell vaso-occlusion

Recent research has high-lighted the importance of leukocytes in sickle cell disease (SCD). Here we summarize evidence to show that the granulocytes may play a role in SCD due to their increased numbers and adhesive properties, facilitating their participation in the vaso-occlusive process.

Hypodontia in an adolescent with the HbSC genotype: a case report

The haemoglobin SC (HbSC) genotype is a variant form of haemoglobin disorder that often presents less frequent clinical symptoms of sickle cell disease (SCD) than the homozygous state (HbSS). Various dental abnormalities, such as enamel hypoplasia, hypomineralization, midline diastema and delayed eruption of the teeth, have been associated with SCD. This report presents the case of an adolescent patient with HbSC who had hypodontia, transposition of a permanent canine, retained primary teeth, multiple carious lesions and poor oral hygiene complicated by sickle cell crisis. This report focuses on the need for preventive care in such patients to reduce functional and aesthetic complications.

Increased adhesive properties of eosinophils in sickle cell disease

OBJECTIVE

A role for leukocytes in vasoocclusion is becoming increasingly recognized. Here we investigate a possible role for the eosinophil in sickle cell anemia (SCA).

PATIENTS AND METHODS

Eosinophils were isolated from whole blood samples of 59 steady-state SCA homozygous SS and control individuals using Percoll gradient separation, followed by immunomagnetic sorting. Adhesion of cells to FN was evaluated using static adhesion assays (60 min, 37 degrees C, 5% CO2) and eosinophil adhesion molecular expression was observed by flow cytometry.

RESULTS

SCA patients presented significantly elevated absolute eosinophil numbers. Furthermore, eosinophils isolated from these individuals demonstrated a significantly greater adhesion ( approximately 70% increased) to fibronectin (FN) than normal eosinophils in static adhesion assays. Coincubation of eosinophils with integrin-blocking monoclonal antibodies in adhesion assays showed that an association of the VLA-4, LFA-1, and Mac-1 integrins mediate the adhesion of SCA eosinophils to FN. Flow cytometry demonstrated that the expression of these integrins, however, was unaltered on the surface of SCA eosinophils, suggesting that the increased SCA eosinophil adhesion is a consequence of increased integrin affinity or avidity. SCA eosinophil adhesion to FN was further increased by the cytokine, GM-CSF, indicating that inflammation processes may further stimulate eosinophil adhesion in these patients.

CONCLUSION

We report that eosinophil numbers may be significantly increased in SCA individuals and that these cells appear to exist in an activated state. Such alterations may indicate a role for the eosinophil in the vasooclusive process.

Gene-environment interplay in relation to emotional and behavioral disturbance

The conceptual and methodological issues involved in the study of gene-environment correlations (rGE) and interactions (GxE) are discussed in historical context. Quantitative genetic findings are considered with respect to rGE and GxE in relation to emotional and behavioral disturbance. Key conceptual and substantive implications are outlined in relation to both genetic and environmental risk mediation, with a brief note on evolutionary considerations.

Splenectomy versus conservative management for acute sequestration crises in people with sickle cell disease

BACKGROUND

Acute splenic sequestration crises are a complication of sickle cell disease, with high mortality rates and frequent recurrence in survivors of first attacks. Splenectomy and blood transfusion, with their consequences, are the mainstay of long term management used in different parts of the world.

OBJECTIVES

To assess whether splenectomy (total or partial) to prevent acute splenic sequestration crises in people with sickle cell disease improved survival and decreased morbidity in patients with sickle cell disease, as compared with regular blood transfusion.

SEARCH STRATEGY

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group specialist trials register which comprises references identified from comprehensive electronic database searches, hand searching relevant journals and hand searching abstract books of conference proceedings Additional randomized controlled trials were sought from the reference lists of the studies found and reviews identified by the search strategy. Date of the most recent search: December 2001

SELECTION CRITERIA

All randomized or quasi-randomized controlled trials comparing splenectomy (total or partial) to prevent recurrence of acute splenic sequestration crises to no treatment or blood transfusion in people with sickle cell disease.

DATA COLLECTION AND ANALYSIS

No trials of splenectomy for acute splenic sequestration were found.

MAIN RESULTS

No trials of splenectomy for acute splenic sequestration were found.

REVIEWER'S CONCLUSIONS

Splenectomy, if full, will prevent further sequestration and if partial, may reduce the recurrence of acute splenic sequestration crises but there is lack of evidence from trials that it improves survival and decreases morbidity in sickle cell disease. There is a need for a well-designed, adequately powered randomised controlled trial to assess the benefits and risks of splenectomy compared to transfusion programmes as a means of improving survival and decreasing mortality from ASS in people with sickle cell disease.

Interleukin 8 as a vaso-occlusive marker in Brazilian patients with sickle cell disease

Sickle cell disease has a worldwide distribution and is a public health problem in Brazil. Although vaso-occlusive crisis (VOC) is one of the most important clinical features of the disease, there are still several steps of its pathogenesis which are unknown. The increase of the chemotactic factor interleukin 8 (IL-8) has been reported to be involved in sickle cell disease crisis, but this has not been demonstrated conclusively. In the present study we analyzed serum IL-8 levels by ELISA and hematological parameters and hemoglobin patterns by standard techniques in 23 (21 SS and 2 SC) Brazilian patients with sickle cell syndromes during VOC caused by different inducing factors, 22 (21 SS and 1 SC) sickle cell patients out of crisis, and 11 healthy controls. Increased IL-8 levels were observed in 19 of 23 VOC patients (79.2%), 3 of them with more than 1,000 pg/ml. Seventeen of 22 (77.3%) non-crisis patients showed low IL-8 levels (less than 15 pg/ml). Healthy controls had low IL-8 levels. A significant difference in serum IL-8 levels was observed between crisis and non-crisis sickle cell patients (P<0.0001). There was no correlation between IL-8 levels and hematological data or hemoglobin patterns. High serum IL-8 levels were observed in VOC patients independently of the crisis-inducing factor. We conclude that in the studied population, IL-8 concentration may be a useful VOC marker, although the mechanism of the pathogenic process of sickle cell VOC syndromes remains unclear.

Nomegestrol acetate contraceptive implant use by women with sickle cell disease

OBJECTIVE

To assess the contraceptive effectiveness, safety, and potential health benefits of nomegestrol acetate contraceptive implant use by women with homozygous sickle cell disease (hemoglobin SS).

METHODS

This was a prospective observation before and after insertion of nomegestrol acetate of 20 women with sickle cell disease (test group) compared with 10 women with similar sociodemographic backgrounds. Changes in hematologic and biochemical parameters and symptoms of sickle cell crisis were measured during 12 months of observation.

RESULTS

After use of nomegestrol acetate for 1 to 9 months, the women in the test group had symptomatic improvement, with no crisis that required hospitalization and no deaths. Sickle cell symptoms persisted in the women in the control group, with 1 recorded death. Increases in F-cell and fetal hemoglobin parallel the observed clinical improvement in the treated women. There were no adverse hematologic or biochemical changes associated with the use of nomegestrol acetate implants.

CONCLUSION

Nomegestrol acetate appears to be a safe and appropriate contraceptive for women with sickle cell disease, showing evidence of being a "stimulant" for F-cell reactivation, independent of F hemoglobin total production increase.

Blood Polymorphonuclear Leukocytes From the Majority of Sickle Cell Patients in the Crisis Phase of the Disease Show Enhanced Adhesion to Vascular Endothelium and Increased Expression of CD64

There is increasing interest in the role of blood polymorphonuclear leukocytes (PMNs) in the pathogenesis of sickle cell crisis. We studied the adherence of PMNs from 18 sickle cell patients in crisis, 25 out of crisis, and 43 healthy subjects (controls) to monolayers of human umbilical cord endothelium that were either untreated or pretreated with tumor necrosis factor α (TNFα). Overall, the PMNs from patients in crisis were more adherent than control PMNs to untreated endothelial monolayers (mean 53% increase; P < .001) and TNFα-treated monolayers (mean 41% increase; P < .002). Increased adhesiveness was not associated with an abnormal expression of CD11a, CD11b, CD11c, CD18, CD62L, or CD15. There was an increase in the number of PMNs expressing CD64 in patients in crisis (median value, 44%) compared with patients out of crisis (median, 21%; P = .025) and controls (median, 6.5%; P < .001). Sera from patients in crisis had normal levels of granulocyte colony-stimulating factor, granulocyte-macrophage colony-stimulating factor, interferon-γ, TNFα, interleukin-1 (IL-1), IL-6, or IL-8 and did not modify the adherence of PMNs or their expression of CD64. Only IFN-γ induced CD64 expression on PMNs, but this effect was not associated with enhanced binding to endothelium. Because PMNs bound to endothelial monolayers were CD64+ and CD64-enriched PMNs were 7 times more adherent to endothelial monolayers than CD64-depleted PMNs, it is likely that CD64 is a marker of adherent PMNs. Two of the three anti-CD64 antibodies used in our antibody blocking studies (clones 32.2 and 197) partially inhibited the binding of sickle cell PMNs to untreated endothelium (mean inhibitions of 33% [P = .01] and 21% [P = .03], respectively), whereas only one (clone 197) inhibited binding to TNFα-treated endothelium (mean inhibition, 29%; P = .004). In some patients with sickle cell disease, an enhanced PMN adhesion to vascular endothelium could contribute to the vascular occlusion that characterizes the acute crisis of the disease.

Blood Polymorphonuclear Leukocytes From the Majority of Sickle Cell Patients in the Crisis Phase of the Disease Show Enhanced Adhesion to Vascular Endothelium and Increased Expression of CD64

There is increasing interest in the role of blood polymorphonuclear leukocytes (PMNs) in the pathogenesis of sickle cell crisis. We studied the adherence of PMNs from 18 sickle cell patients in crisis, 25 out of crisis, and 43 healthy subjects (controls) to monolayers of human umbilical cord endothelium that were either untreated or pretreated with tumor necrosis factor α (TNFα). Overall, the PMNs from patients in crisis were more adherent than control PMNs to untreated endothelial monolayers (mean 53% increase; P < .001) and TNFα-treated monolayers (mean 41% increase; P < .002). Increased adhesiveness was not associated with an abnormal expression of CD11a, CD11b, CD11c, CD18, CD62L, or CD15. There was an increase in the number of PMNs expressing CD64 in patients in crisis (median value, 44%) compared with patients out of crisis (median, 21%; P = .025) and controls (median, 6.5%; P < .001). Sera from patients in crisis had normal levels of granulocyte colony-stimulating factor, granulocyte-macrophage colony-stimulating factor, interferon-γ, TNFα, interleukin-1 (IL-1), IL-6, or IL-8 and did not modify the adherence of PMNs or their expression of CD64. Only IFN-γ induced CD64 expression on PMNs, but this effect was not associated with enhanced binding to endothelium. Because PMNs bound to endothelial monolayers were CD64+ and CD64-enriched PMNs were 7 times more adherent to endothelial monolayers than CD64-depleted PMNs, it is likely that CD64 is a marker of adherent PMNs. Two of the three anti-CD64 antibodies used in our antibody blocking studies (clones 32.2 and 197) partially inhibited the binding of sickle cell PMNs to untreated endothelium (mean inhibitions of 33% [P = .01] and 21% [P = .03], respectively), whereas only one (clone 197) inhibited binding to TNFα-treated endothelium (mean inhibition, 29%; P = .004). In some patients with sickle cell disease, an enhanced PMN adhesion to vascular endothelium could contribute to the vascular occlusion that characterizes the acute crisis of the disease.

Reversal of multiorgan system dysfunction in sickle cell disease with plasma exchange

A 23-year-old man with sickle cell anemia and multiorgan system dysfunction was treated with plasma exchange during a sickle cell crisis. The patient failed to respond to conventional treatment including hydration, blood transfusions, broad spectrum antibiotics, supplemental oxygen, and analgesics. The clinical picture resembled thrombotic thrombocytopenic purpura (TTP), and the patient responded dramatically to plasma exchange with reversal of a rapidly deteriorating clinical state. This case illustrates possible similarities in the pathophysiology of TTP and sickle cell crisis, and the value of plasma exchange in related critical disease states.

A review of evidence about factors affecting quality of pain management in sickle cell disease

OBJECTIVE

To assess the evidence for pharmacological, behavioural, and interpersonal influences on quality of pain management in sickle cell disease.

DATA SOURCES

English-language reports from the research literature up to 1995, identified using Medline, Psychlit, and the Bath Information Data Service.

STUDY SELECTION

Studies are reviewed that (a) reported quantitative clinical outcomes for particular analgesic methods used to treat painful episodes or (b) provide data on patient factors, interpersonal treatment factors, or levels of drug dependence in relation to pain management in sickle cell disease.

DATA SYNTHESIS

Findings vary on the effectiveness of longer-acting opiates, patient-controlled or continuously infused analgesia, and behavioural analgesic techniques, with better results for trials where interpersonal aspects of pain management were also addressed. Risks for poorer pain management are greatest for patients in adverse social circumstances, who are more severely affected by painful episodes and who are poorly adjusted and have less effective personal strategies for coping with pain, but the limited evidence on drug dependence indicates very low levels by comparison with risk and exposure factors.

CONCLUSIONS

Analgesic methods and approaches should continue to be developed and evaluated, but conflicting perceptions between patients and staff about pain that is reported and analgesia that is required probably contribute most to poor pain management in sickle cell disease. Promising areas for future research include the assessment of patients' everyday pain coping styles and patterns of drug use in relation to their hospital experiences of pain management, and the evaluation of psychological interventions to improve patients' styles and strategies for coping with pain.

Nursing management of children with sickle cell disease: an update

This article reviews current trends in managing children with sickle cell disease (SCD). The pathophysiology, medical and nursing management, and complications of SCD are discussed. Current trends and research findings related to improving the prognosis of children with SCD are offered. The importance of the nurse's role in educating the family about the disease process and clinical interventions to prevent or manage complications are stressed. Lastly, a nursing care plan is offered which focuses on pertinent nursing diagnosis.

Screening and prenatal diagnosis of the haemoglobinopathies

In this paper we have reviewed the social and technical aspects of carrier screening and prenatal diagnosis of the inherited haemoglobinopathies. The characteristics of programmes based on carrier screening and prenatal diagnosis ongoing in a number of at-risk Mediterranean populations have been described. The most relevant and common aspects of these programmes are the continuous educational campaign directed to the population at large, the voluntary basis and non-directive counselling. The target population has been most commonly couples before or after marriage. The vast majority of couples counselled accepted prenatal diagnosis. All programmes have encountered a high degree of success as indicated by the marked reduction in the birth rate of infants with thalassaemia major. No significant adverse effects have been reported. A programme with similar characteristics and for which the preliminary results are encouraging, is operating for sickle cell anaemia in the Cuban population. In a population with high frequency of hydrops fetalis, screening for deletion alpha-thalassaemia is recommended to prevent the negative effects on a pregnant woman of the presence of an hydropic fetus. Thalassaemia carrier screening is now carried out by automatic red cell indices and HbA2 determination. Definition of atypical cases may require iron studies, globin chain synthesis determination and/or alpha, beta- and delta-globin gene analysis. Identification of the carrier state is followed by definition of the mutation on enzymatically amplified DNA. Known mutations may be detected by restriction endonuclease analysis, non-denaturing polyacrylamide gel electrophoresis, allele-specific primers or allele-specific probes. The most promising procedures, which are also amenable to complete automation are reverse oligonucleotide hybridization and primer-specific amplification. Unknown mutations are defined by denaturing gradient gel electrophoresis, single-strand conformation polymorphism analysis, and chemical mismatch cleavage analysis followed by direct sequencing. The same methods on enzymatically amplified chorionic villus DNA are used for prenatal diagnosis. The potential pitfall resulting from maternal contamination can be avoided by careful dissection of the maternal decidua from the chorion and by the simultaneous amplification of a suitable polymorphism.

Ketorolac for sickle cell vaso-occlusive crisis pain in the emergency department: lack of a narcotic-sparing effect

STUDY OBJECTIVE

To determine if a single dose of intramuscular ketorolac given on presentation to the emergency department has a narcotic-sparing effect in adult patients with sickle cell vaso-occlusive crisis pain.

DESIGN

A prospective, randomized, single-dose, double-blind study.

SETTING

ED of a university hospital and an affiliated county hospital.

TYPE OF PARTICIPANTS

Eighteen adult patients who presented to the ED with sickle cell crisis pain a total of 24 times.

INTERVENTIONS

Patients were randomized to receive either ketorolac 60 mg IM or placebo on presentation to the ED. Subjects were administered meperidine on presentation and then received a standardized dose of meperidine every 30 minutes during the four-hour observation period based on the severity of pain.

MEASUREMENTS AND MAIN RESULTS

The 12 subjects in the ketorolac group received an average of 231 +/- 92 mg meperidine, whereas the 12 subjects in the placebo group received an average meperidine dose of 250 +/- 85 mg (P = .61).

CONCLUSION

The use of intramuscular ketorolac did not lead to a clinically significant reduction in the requirement for narcotics during the four-hour ED treatment period.

Bone marrow transplantation for severe sickle cell anaemia

Five children with sickle cell anaemia underwent bone marrow transplantation (BMT) for severe clinical disease. The conditioning regimen for BMT was in busulfan plus cyclophosphamide. The allograft contained more than 5 x 10(8) nucleated cells per kg recipient. Prophylaxis of GVHD consisted of methotrexate and cyclosporin A. Therapy was well tolerated. Duration of neutropenia (less than 0.5 x 10(9)/l) was short (14-25 d). Platelet recovery (greater than 50 x 10(9)/l) occurred between day 12 and 45. The patients have been followed up for 8-28 months. No major infections occurred and long-term BMT-related toxicity was limited to mild, chronic GVHD in one patient. Mean haemoglobin levels remained above 10 g/dl. Haemoglobin electrophoresis showed AS patterns in all grafted patients--all marrow donors having sickle cell trait. From our preliminary data, we conclude that BMT or sickle cell anaemia is curative, well tolerated and should be proposed for suitable patients.

Delayed haemolytic transfusion reactions in patients with sickle cell disease

We describe two cases which illustrate the difficult diagnostic and therapeutic problems posed by delayed haemolytic transfusion reactions in patients with sickle-cell disease. The cases emphasize the need for meticulous phenotypic and serological assessment of sickle-cell patients prior to transfusion therapy.

Patterns of mortality in sickle cell disease in the United Kingdom

Eighteen of 384 patients entered on the Brent sickle cell disease register died between 1974 and 1989, a mortality of one per 128 years of follow up. Two children died from acute splenic sequestration and a third died from fulminant pneumococcal septicaemia: none was taking prophylactic penicillin. Acute chest syndrome was the cause of death in eight young adults and one child. Three deaths occurred after surgery. Cerebrovascular accidents contributed to the cause of death in three cases and there were two sudden unexplained deaths. Ten of the deaths occurred at home or within 24 hours of admission to hospital. Post mortem examinations were made in 14 cases, but the histological appearances of acute chest syndrome were often not recognised. In most cases for whom information was available, the cause of death (chest syndrome, pneumococcal sepsis, postoperative complications) could have been prevented.

Transfusion and the use of blood products

I have reviewed areas of development in the use of blood and blood products, placing emphasis on the complications of transfusion, particularly transmission of infection. Alloimmunization in relation to transfusion of red cells and platelets has been covered and suggestions for reducing this problem assessed. The potential methods of avoiding the infective complications have been discussed including the screening of blood for infective agents, the virucidal treatment of blood products during the manufacturing process and white cell depletion. The use of recombinant DNA technology to produce coagulation factors offers the possibility of further reducing infective risks. An area of clinical promise is the use of haematopoietic growth factors to treat bone marrow failure, either congenital or acquired, such as the myelosuppressive effects of cancer chemotherapy, and reduce reliance on blood products. The aim of the chapter is to encourage the rational use of a limited resource by considering the risks inherent in transfusion and alternative strategies. In doing this it is important to audit current and future practice, and it is suggested that reference is made to the suggestions of Hume (1989) for quality assessment and assurance in paediatric transfusion medicine.

Management of sickle cell anemia and pregnancy

There has been significant decrease in maternal morbidity and mortality of sickle cell disease patients during pregnancy due to better understanding of the pathophysiology of the disease and physiologic changes during pregnancy. Prophylactic blood transfusion does not appear to reduce complications in patients with sickle cell anemia. Patients with sickle hemoglobin C disease and with S beta thalassemia+ have fewer complications but still need close monitoring. Blood transfusion therapy should be made available for medical and obstetrical complications to include increasing hypoxemia, progressive anemia, acute chest syndrome, twin pregnancy, splenic sequestration syndrome, preeclampsia, septicemia, or prior to general anesthesia and surgery. Blood transfusion therapy is associated with hepatitis, allergic reaction, alloimmunization, AIDS, and iron overload states. These aspects should be considered prior to using blood transfusion therapy. Excellent prenatal monitoring and aggressive intervention should be instituted when problems arise for the successful management of the pregnant patient with sickle cell disease. Prenatal diagnosis and cord blood screening should be made available for the infant. Appropriate pediatric referral and prophylactic penicillin is recommended for the infant with sickle cell disease.

Continuous papaveretum infusion for the control of pain in painful sickling crisis

We describe our experience of using continuous papaveretum infusions to control pain in 24 children admitted on 45 occasions with painful sickling crisis. The children were aged from 1.7 to 14.3 years. Infusion duration ranged from one to nine days (median three days), total dose from 0.3 to 21 mg/kg (median 2.4 mg/kg), with a pronounced tendency for dosage to increase with increasing age. No respiratory depression was observed. One infusion was discontinued because of cerebral toxicity.