Sickle cell disease: clinical management

The Risk of Kidney Injury in Patients With Sickle Cell Disease Treated With Ketorolac for Acute Pain

Ketorolac, a nonsteroidal anti-inflammatory drug, is used in combination with opioids to manage vaso-occlusive episodes (VOEs). The relationship between ketorolac use and kidney injury in pediatric patients with sickle cell disease (SCD) remains incompletely understood. We hypothesize that ketorolac is associated with acute kidney injury (AKI) in patients with SCD presenting with pain. All nonsurgical hospitalizations for VOEs treated with ketorolac between January 2014 and December 2022 were included. We used optimal matching methodology to identify control admissions (2:1 ratio) and used nonparametric tests to compare ketorolac administration between cases and controls. A total of 1319 encounters/253 patients were included in this study. AKI was noted in 1.1% of encounters and 5.5% of patients. Cases had significantly higher initial BUN than controls (9.0 vs. 6.0 mg/dL, P =0.012). In cases versus controls, there was significantly lower serum sodium (136.0 vs. 138.0 mmol/L, P =0.021). There was no association between ketorolac dose and development of AKI among children with SCD. Higher BUN and lower sodium in cases suggest that patients with AKI were more volume depleted on admission than controls. This highlights the need for strict assessment of fluid status upon admission for VOE.

Genotypic and Phenotypic Composition of Sickle Cell Disease in the Arab Population - A Systematic Review

Sickle cell disease (SCD) is a genetic disease influenced by ethnicity and regional differences in its clinical course. Recent advances in the management of SCD with newer therapies are being introduced to the Western population. However, many of these treatments are yet to be used in the Arabic SCD population. Understanding the genetic variations of SCD regionally is essential to anticipate the utilization of new treatments. This systematic review's main objective is to pool the available data on the genetic composition of SCD in the Arabic population. Data for 44,034 patients was extracted from 184 studies (11 case reports, 8 case series, 56 retrospectives, 107 prospective observational studies, and 2 clinical trials) using PubMed, Scopus, and Google Scholar. Male (49%) and female (51%) patients were equally reported wherever gender was available (N=13105). Various SCD genotypes were reported in a total of 14,257 patients, including Hb SS (77%) Hb Sβ0 (9.9%), and Hb Sβ+ (7.2%), while the rest of the genotypes, including HbSC, HbSD, HbSE, HbSO Arab, Hb S/α-Thal, Hb Sβ0 + α-Thal, and HBS Oman were individually reported in <4% of the cases. Major SCD complications in the Arab population included pain crises (48.25%) followed by neurological complications (33.46%), hepatobiliary complications (25.53%), musculoskeletal complications (24.73%), and hemolytic anemia (23.57%). The treatments reported for SCD included hydroxyurea (20%), blood transfusion (14.32%), and Deferasirox (3.03%). We did not find the use of stem cell transplantation or newer treatments such as L-Glutamine, Voxelotor, Crizanlizumab, or gene therapy reported in any of the studies included in our review. This review highlights the genetic makeup of SCD in Arab countries and its common phenotypic manifestations and will help direct further research on SCD in this region, especially concerning genetic therapy.

Systematic Review Registration

The protocol has been registered in the International Prospective Register of Systematic Reviews(PROSPERO):CRD42020218,666. https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=218666.

Pediatric Sickle Cell Disease and Stroke: A Literature Review

Both ischemic and hemorrhagic strokes in children can be a complication of sickle cell disease, which also affects adults. The occurrence is high without any screening or preventative care. This review article found that although transcranial Doppler (TCD) has reduced the prevalence of stroke in pediatric patients, there is still a need for an epidemiological survey to define such screening for adults, the ideal dose of hydroxyurea to reduce the incidence of stroke, and to identify silent cerebral stroke to prevent its complications. Increased hydroxyurea prescription and specific antibiotic and vaccination regimes lowered the occurrence of this condition. In pediatric cases with a time-averaged mean of the maximal velocity greater than 200cm/s, transcranial Doppler screening and preventive chronic transfusion for at least the first year have lowered the occurrence of stroke by up to 10 times. The ideal dose of hydroxyurea is still debatable, but it seems to reduce the risk of the first stroke to a comparable level in the average population. Adult ischemic and hemorrhagic stroke prevention has not yet received the same attention. Though there are fewer studies, sickle cell disease is also more common than age-matched controls in terms of silent cerebral infarction on magnetic resonance imaging (MRI), as well as other neurological problems such as cognitive impairment, seizures, and headaches. Currently, there is no evidence-supported way to prevent ischemic stroke in adults at any age. Also, there is no defined ideal dose of hydroxyurea that can be helpful in preventing strokes. Data also lack a way to identify a silent cerebral infarction, so its complications can be prevented. An additional epidemiological survey may help in the prevention of the condition. The primary aim of this article was to emphasize the importance of information on clinical, neuropsychological, and quantitative MRI assessment of sickle cell patients to understand the epidemiology and etiology of stroke in sickle cell patients to prevent stroke and its related morbidity.

Epidemiology of Stroke in Sickle Cell Disease

Sickle cell disease is the most common cause of stroke in childhood, both ischaemic and haemorrhagic, and it also affects adults with the condition. Without any screening or preventative treatment, the incidence appears to fall within the range 0.5 to 0.9 per 100 patient years of observation. Newborn screening with Penicillin prophylaxis and vaccination leading to reduced bacterial infection may have reduced the incidence, alongside increasing hydroxyurea prescription. Transcranial Doppler screening and prophylactic chronic transfusion for at least an initial year has reduced the incidence of stroke by up to 10-fold in children with time averaged mean of the maximum velocity >200 cm/s. Hydroxyurea also appears to reduce the incidence of first stroke to a similar extent in the same group but the optimal dose remains controversial. The prevention of haemorrhagic stroke at all ages and ischaemic stroke in adults has not yet received the same degree of attention. Although there are fewer studies, silent cerebral infarction on magnetic resonance imaging (MRI), and other neurological conditions, including headache, epilepsy and cognitive dysfunction, are also more prevalent in sickle cell disease compared with age matched controls. Clinical, neuropsychological and quantitative MRI screening may prove useful for understanding epidemiology and aetiology.

A systematic review of ketamine for the management of vaso-occlusive pain in sickle cell disease

Vaso-occlusive episodes (VOEs) are a common complication of sickle cell disease (SCD) and a significant cause of morbidity. Managing VOE pain can be difficult and complex. Ketamine, an N-methyl-D-aspartate (NMDA) receptor antagonist, has been used to manage VOE pain. This systematic literature review synthesizes research published from 2010 to 2020 on the use of ketamine infusion to decrease VOE pain. The review demonstrates that ketamine, a safe and effective treatment for VOE pain, could be considered more widely. However, the significant variability among published clinical studies with regard to dosing, timing of initiation, duration of infusion, and timing of discontinuation highlights the need for standardized ketamine infusion protocols for the management of VOE pain. We conclude with a brief discussion of key components of a potential standardized protocol supported by the literature reviewed as well as areas for future investigation.

Sickle cell disease: Clinical presentation and management of a global health challenge

Sickle cell disease is an autosomal recessive, multisystem disorder, characterised by chronic haemolytic anaemia, painful episodes of vaso-occlusion, progressive organ failure and a reduced life expectancy. Sickle cell disease is the most common monogenetic disease, with millions affected worldwide. In well-resourced countries, comprehensive care programs have increased life expectancy of sickle cell disease patients, with almost all infants surviving into adulthood. Therapeutic options for sickle cell disease patients are however, still scarce. Predictors of sickle cell disease severity and a better understanding of pathophysiology and (epi)genetic modifiers are warranted and could lead to more precise management and treatment. This review provides an extensive summary of the pathophysiology and management of sickle cell disease and encompasses the characteristics, complications and current and future treatment options of the disease.

The challenge of differentiating vaso-occlusive crises from osteomyelitis in children with sickle cell disease and bone pain: A 15-year retrospective review

PURPOSE

The paediatric sickle cell disease (SCD) osteomyelitis (OM) incidence is 0.3% to 12%. Differentiating vaso-occlusive crises (VOC) from OM is a diagnostic challenge, with limited evidence guiding management. We present a 15-year review of a paediatric sickle cell cohort. We aim to identify OM incidence and provide a management protocol for these children presenting with bone pain.

METHODS

A prospective database of children with haemoglobinopathies (2002 to 2017) was analyzed for temperature, C-reactive protein (CRP) and white cell count (WCC) on admission as well as imaging, treatment and cultures. OM diagnosis was supported by imaging and blood cultures. VOC was defined as bone pain that improved without antibiotics.

RESULTS

Over 15 years, 96 children with SCD presented 358 times to hospital. Empirical antibiotics were given in 308 presentations. There were five cases of OM (1.4%); two acute and three chronic. In all, 50 presentations of VOC were identified. No significant differences in age were noted between the OM and VOC group. Temperature and CRP were significantly elevated in the OM group with no significant difference in WCC. Cultures were only positive in the chronic OM admissions. There were no cases of septic arthritis. No surgical intervention was required.

CONCLUSION

In children with SCD presenting with persistent bone pain, fever, elevated CRP and WCC, OM should be suspected and prompt antibiotic treatment started. Our treatment pathway was successful avoiding OM in 98.6% and septic arthritis in 100%. Further research on novel biological markers distinguishing OM from VOC should be investigated.

LEVEL OF EVIDENCE

III.

Ketamine Infusion for Pain Control in Acute Pediatric Sickle Cell Painful Crises

OBJECTIVES

Sickle cell disease is the most common hemoglobin variant in the world and can present with recurrent vaso-occlusive painful crises. Pain control in these patients is often difficult and requires a multimodal approach. In patients with uncontrolled pain after traditional pain control methods, ketamine infusions have proven beneficial. Unfortunately, no source alone had described ketamine infusions for pediatric sickle cell patients. Our objective was to provide a thorough definitive reference for health care providers regarding the use of ketamine infusion for pain control in pediatric sickle cell painful crises.

METHODS

Literature review.

RESULTS

Low-dose ketamine infusions for pediatric patients with sickle cell disease painful crises resulted in improved pain scores and reduced opioid usage.

CONCLUSIONS

Ketamine infusions have shown promise in assisting physicians in appropriately treating pediatric sickle cell painful crises.

Massive splenic infarction and splenic venous thrombosis observed in a patient with acute splenic syndrome of sickle cell traits on contrast-enhanced thin-slice computed tomography

We report a case of splenic infarction in a patient with sickle cell traits (SCT), focusing on the computed tomography (CT) findings. The patient was an African-American man in his twenties with no past medical history who experienced sudden left upper quadrant pain while climbing a mountain (over 3000 m above sea level). Dynamic contrast-enhanced CT revealed massive non-segmental splenic infarction accompanied with nodule-like preserved splenic tissue. The region of splenic infarction did not coincide with the arterial vascular territory and differed from the features of infarction caused by large arterial embolism. In addition, thrombotic occlusion of the distal splenic vein was depicted on plain and contrast-enhanced thin-slice CT images. Early-phase contrast-enhanced images also showed inhomogeneous enhancement of the hepatic parenchyma. The patient's symptoms improved with conservative therapy. A hemoglobin electrophoresis test confirmed the diagnosis of SCT. SCT is usually asymptomatic, but hypoxic environments may induce acute splenic syndrome, which is commonly manifested as splenic infarction. We observed splenic venous thrombosis and inhomogeneous hepatic parenchymal enhancement in addition to a huge splenic infarction in our patient. To the best of our knowledge, this is the first report describing the specific imaging findings, particularly splenic venous thrombosis and inhomogeneous hepatic parenchymal enhancement, of acute splenic syndrome in a patient with previously undiagnosed SCT. These findings demonstrate the pathophysiology of SCT, and may help with the diagnosis of this disease.

Severity of Brazilian sickle cell disease patients: severity scores and feasibility of the Bayesian network model use

The integration of the several clinical and laboratory dimensions and the influence of each parameter on the sickle cell disease (SCD)-related mortality is useful for predicting the phenotype of an individual. This study evaluated the feasibility of the SCD severity calculator use to measure disease severity in Brazilian patients. The study group was composed of 500 SCD patients (440 HbSS and 60 HbSC) diagnosed by molecular biology. We observed a decrease in severity scores in 72 SCD patients assessed before and after the hydroxyurea (HU) use. Furthermore, the HU influenced the increase of mean corpuscular volume (MCV) and HbF concentration, and the decrease of leukocytes and total bilirubin. We found 180 (36.0%) patients with intermediate phenotype, 170 (34.0%) mild phenotype and 150 (30.0%) with severe phenotype. Patients with ages >40 years had higher mean score (0.778±0.177) than patients between 18 and 40 years (0.562±0.152) and patients between 5 and 17 years (0.322±0.145). We observe that there is a tendency of individuals with leg ulcers, avascular necrosis and cardiac complications with increasing age. Correlation analysis showed relations between severity scores with leukocytes, reticulocytes, bilirubin, lactate dehydrogenase, HbS, hemoglobin and hematocrit (p<0.05). Several comparisons involving age groups, SCD genotype and phenotypic classification had satisfactory results and this classification will be used for future studies involving genetic polymorphisms, response to treatment with HU and oxidative stress markers in SCD.

Sickle cell disease and pregnancy: analysis of 34 patients followed at the Regional Blood Center of Ribeirão Preto, Brazil

OBJECTIVE

The objective of this study was to verify the evolution of pregnancies in sickle cell patients followed at one institution over a period of 12 years (January 2000 to June 2012).

METHODS

The study evaluated 34 pregnant women with sickle cell disease with a mean age of 23.9±5.3 years. The incidence of obstetric complications, non-obstetric complications linked to sickle cell disease and complications in the newborn were analyzed.

RESULTS

A total of 26% of the cases reported previous miscarriages, 20% had preterm labor, 10% had pre-eclampsia, and 5% had gestational diabetes. Forty-one percent of the deliveries were cesarean sections and 29% of patients required blood transfusions. In respect to sickle cell disease, 62% of patients had vaso-occlusive crises, 29% had acute chest syndrome, 23% had urinary tract infection, 15% had impaired cardiac function and 6% developed pulmonary hypertension. Only one patient died in the postnatal period due to acute chest syndrome. The mean gestational age was 37.8±2.63 weeks, and mean newborn weight was 2.809±643.8g. There were seven fetal losses, including three stillbirths and four miscarriages. The impact of transfusion therapy on the incidence of maternal-fetal complications during pregnancy was evaluated.

CONCLUSIONS

Pregnancy in sickle cell patients is still associated with complications. Although no statistical difference was observed between transfused and non-transfused women, there were no deaths (fetal or maternal) in transfused patients whereas one maternal death and three stillbirths occurred in non-transfused women. A larger study of sickle cell pregnant women will be necessary to elucidate the actual role of transfusion during pregnancy in sickle cell disease.

WITHDRAWN: Pain management for sickle cell disease in children and adults

This review is out of date, and the original authors are no longer available to update it. If you are interested in updating this review, please contact PaPaS: https://papas.cochrane.org/contact‐us

At October 2015, a new author team is preparing a replacement review to focus on acute sickle cell crises in adults.

The editorial group responsible for this previously published document have withdrawn it from publication.

An Intervention to Decrease Stigma in Young Adults With Sickle Cell Disease

Young adults with sickle cell disease (SCD) are often stigmatized when they seek care for pain. The purpose of this pilot study was to test an intervention to decrease health-related stigma during care-seeking. Young adults with SCD ages 18 to 35 years ( n = 90) were randomized to either the care-seeking intervention (CSI) or an attention control group that participated in life review interviews. The two groups were compared by t tests and longitudinal data analyses on the change from baseline to the last time point in total health-related stigma and health-related stigma by doctors. Findings suggest that the CSI was associated with significant increased awareness of perceived total stigma and stigma by doctors compared with the attention control group. These findings are promising in terms of lessons learned from a pilot intervention that focused on the role communication skills play in decreasing health-related stigma in young adults with SCD.

Sickle cell disease: management options and challenges in developing countries

Sickle Cell Disease (SCD) is the most common genetic disorder of haemoglobin in sub-Saharan Africa. This commentary focuses on the management options available and the challenges that health care professionals in developing countries face in caring for patients with SCD. In a developing countries like Ghana, new-born screening is now about to be implemented on a national scale. Common and important morbidities associated with SCD are vaso-occlusive episodes, infections, Acute Chest Syndrome (ACS), Stroke and hip necrosis. Approaches to the management of these morbidities are far advanced in the developed countries. The differences in setting and resource limitations in developing countries bring challenges that have a major influence in management options in developing countries. Obviously clinicians in developing countries face challenges in managing SCD patients. However understanding the disease, its progression, and instituting the appropriate preventive methods are paramount in its management. Emphasis should be placed on early counselling, new-born screening, anti-microbial prophylaxis, vaccination against infections, and training of healthcare workers, patients and caregivers. These interventions are affordable in developing countries.

Oral ketamine for sickle cell crisis pain refractory to opioids

There is literature demonstrating that the N-methyl-d-aspartate (NMDA) receptor antagonist ketamine has analgesic properties that can be used as an adjuvant to opiates for pain relief in multiple various conditions and pain states. However, there is a lack of published information on ketamine used in persons with sickle cell disease in acute pain crises. The Virginia Commonwealth University Palliative Care team was consulted on a 38-year-old African American female with sickle cell thalassemia in severe acute pain crisis overlying chronic pain related to her disease. Pain control was unable to be achieved with escalating doses of opiates and other adjuvant medications. The patient responded well to an intravenous test dose of ketamine and was subsequently placed on an oral regimen of ketamine in addition to opiates. In the 24-hour period following ketamine initiation, the patient's pain was able to be controlled on decreased amounts of opiates. She was eventually transitioned to an oral opiate and ketamine regimen, which allowed her to be discharged home with pain levels close to her baseline and the ability to function and perform all activities of daily living.

Sickle cell pain: a critical reappraisal

Sickle cell pain includes 3 types: acute recurrent painful crises, chronic pain syndromes, and neuropathic pain. The acute painful crisis is the hallmark of the disease and the most common cause of hospitalization and treatment in the emergency department. It evolves through 4 phases: prodromal, initial, established, and resolving. Each acute painful episode is associated with inflammation that worsens with recurrent episodes, often culminating in serious complications and organ damage, such as acute chest syndrome, multiorgan failure, and sudden death. Three pathophysiologic events operate in unison during the prodromal phase of the crisis: vaso-occlusion, inflammation, and nociception. Aborting the acute painful episode at the prodromal phase could potentially prevent or minimize tissue damage. Our hypothesis is that managing these events with hydration, anti-inflammatory drugs, aggressive analgesia, and possibly vasodilators could abort the crisis and prevent or minimize further damage. Chronic pain syndromes are associated with or accompany avascular necrosis and leg ulcers. Neuropathic pain is not well studied in patients with sickle cell disease but has been modeled in the transgenic sickle mouse. Management of sickle cell pain should be based on its own pathophysiologic mechanisms rather than borrowing guidelines from other nonsickle pain syndromes.

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.

Tuberculous spondylodiscitis in a patient with a sickle-cell disease: CT findings

Background:

Although sickle-cell anemia (SCA) is common in black Americans, Sub-Saharan Africa and in the Mediterranean area, the disease is rare in the temperate climate zone. The manifestations of the disease are related mainly to the production of abnormal hemoglobin that leads to organ ischemia and increased susceptibility to infection caused by functional asplenia.

Case Report:

The authors present CT findings in a 39-year-old black woman diagnosed due to abdominal pain, lymphadenopathy and fever. CT of the thorax and abdomen demonstrated changes in the liver, spleen, and skeletal system suggestive of SCA complicated with spondylodiscitis in the thoracic spine.

Discussion:

Hepatomegaly and small calcified spleen are typical findings in older homozygotic patients with SCA. The lesions in the skeleton may be related either to intramedullary hematopoiesis or osteonecrosis and osteomyelitis. In the latter case, diffuse osteosclerosis and H-shaped vertebrae are most typical. Tuberculous spondylodiscitis is characterized by the location in the thoracic region, preferential involvement of anterior elements, relative sparing of intervertebral discs, and cold abscesses.

Newborn screening shows a high incidence of sickle cell anemia in Central India

There is limited data on the incidence of sickle cell anemia in Central India; we therefore conducted a study to estimate the incidence of this disease in Central India. Mothers who delivered a live baby at the Government Medical College, Nagpur, India were screened for the presence of the sickle cell hemoglobin {Hb S: [β6 (A3) Glu→Val, GAG>GTG]} using the solubility test within 48 hours of delivery. Infants of mothers who showed the presence of Hb S then underwent Hb analysis by high performance liquid chromatography (HPLC). A total of 8243 mothers was screened, 1178 of whom were positive. One thousand, one hundred and sixty-two infants of mothers with a positive solubility test underwent Hb analysis by HPLC; 530 infants were normal, while 536 were heterozygous for Hb S (sickle cell trait), 88 babies were homozygous for Hb S (sickle cell anemia), while another eight babies had other Hb abnormalities. The incidence of sickle cell anemia was highest in the Scheduled caste group (1:50). We concluded that the incidence of sickle cell anemia is high in central India.

Premarital screening test results for β-thalassemia and sickle cell anemia trait in east Mediterranean region of Turkey

Hemoglobinopathies are common diseases in Mediterranean region of Turkey. In this study, the results of a 3-year premarital screening program are reported in Kahramanmaras province, which is located in East Mediterranean region. A total of 48,126 persons were screened in this program. Hematological analyses and electrophoresis were done to identify carriers. The prevalence of β-thalassemia trait and of sickle cell anemia trait, which were 2.1% and 0.5% in Turkey, were found to be 2.8% and 0.4%, respectively, in our study. Of the carriers of the β-thalassemia trait, 82% had high hemoglobin A₂, 34% had high hemoglobin F, and 18% had both high hemoglobin F and hemoglobin A₂. β-Thalassemia trait in Kahramanmaras is slightly higher than the average rate in Turkey. However, sickle cell anemia trait is similar to Turkey's averages.

Apolipoprotein A-I and serum amyloid A plasma levels are biomarkers of acute painful episodes in patients with sickle cell disease

BACKGROUND

Acute painful episodes are the clinical hallmark of sickle cell disease and have been linked to morbidity and mortality in the sickle cell population.

DESIGN AND METHODS

We undertook exploratory proteomic studies on paired plasma samples collected from a cohort of 26 adult sickle cell patients during steady state and on the first day of an acute painful episode. We screened for changes in abundance of specific protein peaks via surface-enhanced laser desorption/ionization time of flight mass spectrometry (SELDI-TOF MS), and confirmed the identify of candidate protein peaks by specific immunoassays.

RESULTS

The levels of hemoglobin, hematocrit, total protein, and albumin were lower and the levels of lactate dehydrogenase and absolute reticulocytes higher during acute painful episodes than during the steady state. Surface-enhanced laser desorption/ionization time of flight mass spectrometry spectral analysis consistently showed a mass-to-charge peak at 11.7 kDa with elevated intensities during acute painful episodes, which correlated significantly with the serum amyloid A immunoassay. Serum amyloid A levels were significantly elevated during acute painful episodes, especially in four patients with marked end-organ complications of such episodes. A second, recurring peak, less abundant during acute painful episodes, was present at 28.1 kDa; this peak was correlated significantly with immunoassay measurements of apolipoprotein A1.

CONCLUSIONS

On the average, plasma serum amyloid A rises and apolipoprotein AI falls during acute painful episodes. The serum amyloid A/apolipoprotein AI ratio increased in 81% of the patients during acute painful episodes, potentially making it a useful objective marker of such episodes. We propose that these protein alterations, known to contribute to endothelial dysfunction in other settings, might do likewise acutely in acute painful episodes and present a new target for therapeutic intervention in sickle cell disease. (ClincalTrials.gov Identifier: NCT00081523).

Can Heterogeneity of Chronic Sickle-Cell Disease Pain Be Explained by Genomics? A Literature Review

This literature review explores the potential of genomics to explain, or at least contribute to the discussion about, heterogeneity in chronic pain in sickle-cell disease (SCD). Background: Adults with SCD, a single-gene disorder, are living longer than in years past, yet report being burdened by chronic pain. With only a few studies on chronic pain in this population, the epidemiology is unclear. However, research in the area of pain genetics continues to advance since the conclusion of the Human Genome Project. Two pain susceptibility genes, catechol-O-methyltransferase (COMT) and cytochrome P450, have, to date, been discovered that can increase individual susceptibility to the development of chronic pain. Method: A search was conducted in PubMed, CINAHL, and EBSCO using the terms ``sickle cell,'' ``chronic pain,'' ``polymorphism,'' ``genetics,'' ``pain genetics,'' ``human,'' ``adult,'' ``association studies,'' and ``pain susceptibility genes'' to search for articles published between 1970 and 2008. Findings: Chronic pain generally is more prevalent and severe than previously reported, and individuals with SCD report daily pain. The genomic era has made it possible for scientists to identify pain susceptibility genes that contribute to variability in the interindividual experience of chronic pain. Conclusion: Nurses are well positioned to generate and translate genomic research, thus improving care delivery. Such research may lead to the identification of polymorphisms associated with pain sensitivity in individuals with SCD.

Peripheral nervous system involvement in patients with sickle cell disease

BACKGROUND AND PURPOSE

Peripheral nervous system involvement is rare in sickle cell disease (SCD). The aim of this study is to determine the peripheral nerve involvement electrophysiologically in SCD patients without clinically evident neurological signs, symptoms and to determine the relationship between the frequency of sickle cell crisis and peripheral neuropathy.

METHODS

Fifty-one patients with SCD and fifty-one healthy controls were enrolled to the study. Conventional electrophysiological studies of peripheral nerves were performed to all subjects. The data about the frequency of sickle cell crisis were obtained.

RESULTS

Peripheral nervous system involvement was detected in ten (19.6%) patients. Five (9.8%) patients had sensorimotor axonal neuropathy, two (3.9%) sensory axonal neuropathy, one (2%) patient had ulnar sensory neuropathy and two (3.9%) had median sensory neuropathy. Sural nerve sensorial action potential was unobtainable in eight (15.7%) patients and prolonged F latencies were observed in three (5.9%). The frequency of neuropathy was higher in SCD patients when compared with the controls. The frequency of sickle cell crisis was not significantly correlated with peripheral neuropathy.

CONCLUSION

Subclinical peripheral nerve involvement may be seen in SCD patients. Electrophysiological examinations are recommended in routine examination to diagnose early neuropathy in SCD patients without neurologic symptoms.

Pain management for sickle cell disease

BACKGROUND

Sickle cell disease is an inherited genetic disorder characterized by an abnormality of haemoglobin that predisposes to polymerization and consequent deformation ("sickling"). Sickle cell disease can cause episodes of acute severe pain. Chronic pain may also occur. Currently, pain is inadequately managed.

OBJECTIVES

The primary aim of the review was to assess the effectiveness of pharmacological analgesic interventions for pain management in sickle cell disease, including the treatment of acute and chronic pain in children and adults.

SEARCH STRATEGY

A pre-defined search strategy was used to electronically search the MEDLINE and EMBASE databases. Searches were also conducted on the Cochrane Controlled Trial Register (CCTR) and the Oxford pain randomised controlled trials citation database. The search period covered from January 1965 through to June 2002. Bibliographies of retrieved studies were searched for additional references. No language restriction was used.

SELECTION CRITERIA

All randomised controlled trials involving pharmacological treatment of acute or chronic pain in children or adults with sickle cell disease were selected. Patients with haemoglobin SS, haemoglobin S ss thalassaemia and the haemoglobin SC group were included.

DATA COLLECTION AND ANALYSIS

Trials were quality rated using the Oxford quality scale. Continuous measures of outcome were combined using weighted mean differences. Overall effect size was calculated with 95% confidence intervals.

MAIN RESULTS

Nine randomised controlled trials were identified. All studies involved small numbers of patients with acute sickle cell pain only. Interventions included NSAIDs (versus placebo in four studies; versus strong opioids in one study), strong opioids (oral versus parenteral in one study; morphine versus alternate in one study) and corticosteroids (versus placebo in two studies). Lack of data, small patient numbers, variations in study design and outcome measures limited the review. Due to heterogeneity of methodologies and reporting, it was not possible to perform meaningful meta-analyses.

AUTHORS' CONCLUSIONS

There were no studies addressing chronic pain in sickle cell disease. There is limited evidence for analgesic interventions in acute pain crises. Studies have been under-powered. There is not enough data for inter-trial comparisons. In one trial, there was no difference in the efficacy of sustained-release oral versus parenteral morphine, which suggests that oral morphine should be considered for acute pain. Parenteral corticosteroids appear to shorten the period over which analgesics are required and hospital length-of-stay, without producing short-term major adverse effects. More research is needed to improve pain management in sickle cell disease.

Fourteen-Year Experience of Prenatal Diagnosis of Thalassemia in Iran

For 14 years, Iranian scientists have worked to develop a national thalassemia prevention program. Although historically abortion was considered unacceptable in Iran, intensive consultations led to the clerical approval of induced abortion in cases with beta-thalassemia major in 1997, and a nationwide prevention program with screening, counseling and prenatal diagnosis (PND) networks has been developed. This paper reports the experience from one of the two national PND reference laboratories. As one of the oldest reference laboratories, we performed a total of 906 PND in 360 couples at risk for thalassemia from 1990 to 2003. Direct and indirect mutation detection methods were applied for all cases. In total, 22 mutations were tested routinely, and an additional 30 rare mutations were identified. 208 fetuses were found to be normal, 215 fetuses had beta-thalassemia major, and 435 fetuses were carriers of the trait. In 40 cases, we only defined one allele. In 8 cases, we were unable to provide any diagnosis, corresponding to 0.9%. Our data support the functionality of the Iranian beta-thalassemia prevention program. The success of this system in Iran, a multiethnic and Islamic-based country, would mean that it might be applied as an adaptive system for neighboring and other Islamic countries.

Endothelial cell NADPH oxidase mediates the cerebral microvascular dysfunction in sickle cell transgenic mice

Although blood cell-endothelial cell adhesion and oxidative stress have been implicated in the pathogenesis of sickle cell disease (SCD), the nature of the linkage between these vascular responses in SCD remains unclear. The objective of this study was to determine whether superoxide derived from endothelial cell-associated NADPH oxidase mediates the leukocyte-endothelial (L/E) and platelet-endothelial cell (P/E) adhesion that is observed in the cerebral microvasculature of sickle cell transgenic (betaS) mice. Intravital fluorescence microscopy was used to monitor L/E and P/E adhesion in brain postcapillary venules of wild-type (WT), SOD1 transgenic (SOD1-TgN), and gp91phox (NADPH oxidase)-deficient mice that were transplanted with bone marrow from betaS mice. Hypoxia/reoxygenation (H/R) yielded intense P/E and L/E adhesion responses in cerebral venules of betaS/WT chimeras that were significantly attenuated in both betaS/SOD1-TgN, and betaS/gp91phox-/- chimeras. Pretreatment of betaS/WT chimeras with the iron-chelator desferroxamine blunted the blood cell-endothelial cell adhesion responses to H/R, whereas pretreatment with the xanthine oxidase inhibitor allopurinol had no effect. These findings suggest that superoxide derived from endothelial cell NADPH-oxidase and catalytically active iron contribute to the proinflammatory and prothrombogenic responses associated with sickle cell disease.

A case for developing North-South partnerships for research in sickle cell disease

For a better understanding of the pathophysiology and mechanisms of phenotypic diversity of sickle cell disease, and for the improvement of its management globally, there is a strong case for developing sustainable research partnerships between rich and poor countries.

Pharmacologic and cytokine treatment of commonly encountered anemias

Anemia has multiple etiologies: it may be caused by nutritional deficiencies or congenital abnormalities, or it may be associated with a number of conditions, such as chronic kidney disease, cancer, or human immunodeficiency virus (HIV) infection. Anemia is associated with an increase in morbidity and mortality in patients with endstage renal disease, cancer, or HIV infection. Each case of anemia is different, with different causes, clinical consequences, and treatment strategies. Identifying the most appropriate treatment requires an understanding of the etiology of the anemia and investigation of the nature of the causative medical condition. In some cases, such as anemia associated with chronic kidney disease, treatment is well defined and consists of administration of erythropoiesis-stimulating agents, accompanied by iron supplementation where appropriate. In other instances, such as megaloblastic anemia, which may be caused by vitamin or folate deficiency, vitamin supplementation alone may be a clinically appropriate treatment. This article gives an overview of the etiologies and current therapies of the most commonly encountered types of anemia, highlighting both the diverse nature of the condition, and the equally diverse pharmacologic and supportive treatment approaches.

Sickle cell disease: the neurological complications

The genetic cause of sickle cell disease has been known for decades, yet the reasons for its clinical variability are not fully understood. The neurological complications result from one point mutation that causes vasculopathy of both large and small vessels. Anemia and the resultant cerebral hyperemia produce conditions of hemodynamic insufficiency. Sickled cells adhere to the endothelium, contributing to a cascade of activated inflammatory cells and clotting factors, which result in a nidus for thrombus formation. Because the cerebrovascular reserve becomes exhausted, the capacity for compensatory cerebral mechanisms is severely limited. There is evidence of small-vessel sludging, and a relative deficiency of nitric oxide in these vessels further reduces compensatory vasodilatation. Both clinical strokes and silent infarcts occur, affecting motor and cognitive function. New data suggest that, in addition to sickle cell disease, other factors, both environmental (eg, hypoxia and inflammation) and genetic (eg, mutations resulting in thrombogenesis), may contribute to a patient's stroke risk. The stroke risk is polygenic, and sickle cell disease can be considered a model for all cerebrovascular disease. This complex disease underscores the potential intellectual and practical distance between the determination of molecular genetics and effective clinical application and therapeutics.

[Presentation of 2 cases of sudden deafness in patients with sickle-cell anemia and trait]

We report two cases of sudden deafness which appeared during vaso-occlusive crisis of a sickle cell anaemia (homozygous form of disease) and a sickle cell trait (heterozygous form) in two males aged sixteen and twenty-two, respectively. A high erythrocyte aggregability and low deformability were proved in both young men. Although hearing disorders have been reported in this disease, a sudden onset is not common. The treatment used was useful in the removal of painful crisis and infections, but deafness did not improve in either of then.

Sickle cell anaemia: progress in pathogenesis and treatment

The phenotypic expression of sickle cell anaemia varies greatly among patients and longitudinally in the same patient. It influences all aspects of the life of affected individuals including social interactions, intimate relationships, family relations, peer interactions, education, employment, spirituality and religiosity. The clinical manifestations of sickle cell anaemia are protean and fall into three major categories: anaemia and its sequelae;pain and related issues; andorgan failure including infection. Recent studies on the pathogenesis of sickle cell anaemia have centred on the sequence of events that occur between polymerisation of deoxy haemoglobin (Hb) S and vaso-occlusion. Cellular dehydration, inflammatory response and reperfusion injury seem to be important pathophysiological mechanisms. Management of sickle cell anaemia continues to be primarily palliative in nature, including supportive, symptomatic and preventative approaches to therapy. Empowerment and education are the major aspects of supportive care. Symptomatic management includes pain management, blood transfusion and treatment of organ failure. Pain managment should follow certain priniciples that include assessment, individualisation of therapy and proper utilisation of opioid and nonopioid analgesics in order to acheive adequate pain relief. Blood selected for transfusion should be leuko-reduced and phenotypically matched for the C, E and Kell antigens. Exchange transfusion is indicated in patients who are transfused chronically in order to prevent or delay the onset of iron-overload. Acute chest syndrome is the most common form of organ failure and its management should be agressive, including adequate ventilation, multiple antibacterials and simple or exchange blood transfusion depending on its severity. Preventitive therapy includes prophylactic penicillin in infants and children, blood transfusion (preferably exchange transfusion) in patients with stroke, and hydroxyurea in patients with frequent acute painful episodes. Bone marrow and cord blood transplantation have been successful modalities of curative therapy in selected children with sickle cell anaemia. Newer approaches to preventative therapy include cellular rehydration with agents that inhibit the Gardos channel or the KCl co-transport channel. Curative gene therapy continues to be investigational at the level of the test tube and transgenic mouse models.

Sickle cell anemia

Sickle cell anemia (SCA) is a disease caused by production of abnormal hemoglobin, which binds with other abnormal hemoglobin molecules within the red blood cell to cause rigid deformation of the cell. This deformation impairs the ability of the cell to pass through small vascular channels; sludging and congestion of vascular beds may result, followed by tissue ischemia and infarction. Infarction is common throughout the body in the patient with SCA, and it is responsible for the earliest clinical manifestation, the acute pain crisis, which is thought to result from marrow infarction. Over time, such insults result in medullary bone infarcts and epiphyseal osteonecrosis. In the brain, white matter and gray matter infarcts are seen, causing cognitive impairment and functional neurologic deficits. The lungs are also commonly affected, with infarcts, emboli (from marrow infarcts and fat necrosis), and a markedly increased propensity for pneumonia. The liver, spleen, and kidney may experience infarction as well. An unusual but life-threatening complication of SCA is sequestration syndrome, wherein a considerable amount of the intravascular volume is sequestered in an organ (usually the spleen), causing vascular collapse; its pathogenesis is unknown. Finally, because the red blood cells are abnormal, they are removed from the circulation, resulting in a hemolytic anemia. For the patient with SCA, however, the ischemic complications of the disease far outweigh the anemia in clinical importance.

Anemia

Anemia is an enormous problem worldwide that is worse in the developing countries but by no means lacking in developed countries. Women and children are disproportionately affected. Nutritional anemias, mainly caused by a lack of iron and folate, are largely correctable by dietary improvement, but this socioeconomic change may not be readily achieved. The inherited disorders, the hemoglobinopathies and thalassemias, in their heterozygous forms are beneficial to the affected populations. Prevention of the homozygous forms and the serious diseases that result can only be addressed by education. These conditions are seen in all types of medical practice ranging from neonatology to geriatrics and public health and are an ongoing concern to all physicians.

Osteoarticular disorders of haematological origin

Clinical abnormalities of the musculoskeletal system may be the first manifestation of sickle haemoglobinopathies, leukaemias, lymphomas and haemophilia. In addition to this, known patients with these diseases exhibit a variety of osteoarticular features. The painful crisis is the most common manifestation of sickle cell disorders, but avascular necrosis, osteomyelitis and various forms of arthritides are also common. In haematological malignancies, bone pain and arthritis may occur at any stage of the disease. The diagnosis must be confirmed by the presence of malignant cells on histological examination of various samples. Haemarthrosis is the main symptom of haemophilia. It needs early treatment to avoid damage to the joints. The availability of new safe coagulation factors has improved the prognosis of haemophilia.