A cautionary note regarding hydroxyurea in sickle cell disease

Abstract Hydroxyurea can increase fetal hemoglobin (HbF) and improve the clinical course of sickle cell disease (SCD) patients. However, several issues of hydroxyurea therapy remain unresolved, including differences in patients' drug clearance, predictability of drug response, reversibility of sickle cell disease-related organ damage by hydroxyurea, and the efficacy of elevated HbF. We treated two patients with hydroxyurea for periods of 1 to 4 years, monitoring clinical course and laboratory parameters at regular intervals. The first patient (patient A) had a history of chronic pain and extensive hospitalizations. The second patient (patient B) had a history of stroke and refused to continue with chronic transfusion therapy and chelation. Both patients showed a fivefold to tenfold increase in HbF (5% to 25%, 3% to 31%). However, patient A developed an acute chest syndrome, despite an HbF level of 20%. After red blood cell transfusions for hypoxia, the HbF level decreased to 5%. When hydroxyurea dosage was increased, pancytopenia developed and was not resolved until 2 months after hydroxyurea was discontinued; Patient B developed a cerebral hemorrhage on hydroxyurea; he died shortly thereafter. His HbF level was 21% before death. We noted an increase in HbF and a general improvement in the two patients. However, both experienced major SCD-related complications despite HbF levels over 20%. Our findings also suggest that the progressive vascular changes associated with SCD are unlikely to be dramatically affected by increased HbF levels. Because neither the efficacy nor the toxicity of hydroxyurea have been thoroughly investigated, physicians should be cautious in prescribing hydroxyurea for patients with SCD before completion of the National Clinical Trial.

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A cautionary note regarding hydroxyurea in sickle cell disease

Blood ◽

10.1182/blood.v83.4.1124.bloodjournal8341124 ◽

1994 ◽

Vol 83 (4) ◽

pp. 1124-1128

Author(s):

EP Vichinsky ◽

BH Lubin

Keyword(s):

Sickle Cell Disease ◽

Sickle Cell ◽

Clinical Course ◽

Fetal Hemoglobin ◽

Organ Damage ◽

Acute Chest Syndrome ◽

Cell Disease ◽

Transfusion Therapy ◽

History Of ◽

Hbf Level

Hydroxyurea can increase fetal hemoglobin (HbF) and improve the clinical course of sickle cell disease (SCD) patients. However, several issues of hydroxyurea therapy remain unresolved, including differences in patients' drug clearance, predictability of drug response, reversibility of sickle cell disease-related organ damage by hydroxyurea, and the efficacy of elevated HbF. We treated two patients with hydroxyurea for periods of 1 to 4 years, monitoring clinical course and laboratory parameters at regular intervals. The first patient (patient A) had a history of chronic pain and extensive hospitalizations. The second patient (patient B) had a history of stroke and refused to continue with chronic transfusion therapy and chelation. Both patients showed a fivefold to tenfold increase in HbF (5% to 25%, 3% to 31%). However, patient A developed an acute chest syndrome, despite an HbF level of 20%. After red blood cell transfusions for hypoxia, the HbF level decreased to 5%. When hydroxyurea dosage was increased, pancytopenia developed and was not resolved until 2 months after hydroxyurea was discontinued; Patient B developed a cerebral hemorrhage on hydroxyurea; he died shortly thereafter. His HbF level was 21% before death. We noted an increase in HbF and a general improvement in the two patients. However, both experienced major SCD-related complications despite HbF levels over 20%. Our findings also suggest that the progressive vascular changes associated with SCD are unlikely to be dramatically affected by increased HbF levels. Because neither the efficacy nor the toxicity of hydroxyurea have been thoroughly investigated, physicians should be cautious in prescribing hydroxyurea for patients with SCD before completion of the National Clinical Trial.

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Sickle Cell Disease

10.1093/med/9780190678333.003.0033 ◽

2018 ◽

Author(s):

Ann Ng ◽

Erin S. Williams

Keyword(s):

African American ◽

Sickle Cell Disease ◽

Sickle Cell ◽

Sickle Cell Anemia ◽

Sickle Cell Trait ◽

Organ Damage ◽

Acute Chest Syndrome ◽

Cell Disease ◽

Systemic Involvement ◽

History Of

Sickle cell anemia (sickle cell disease) is a common hemoglobinopathy with anywhere from 90,000 to 100,000 Americans affected. This chronic condition has a predominance in populations of African descent, occurring in approximately 1 out of 365 African American births, compared to 1 out of 16,300 Hispanic births. The sickle cell trait can be detected in 1 of 13 African American births. One of the most common complications associated with sickle cell anemia, vaso-occlusive crises by sickled cells, results in severe pain. Other issues associated with this condition include acute chest syndrome, lung infections, end organ damage, and stroke. With improvements in the management and prevention of pain crises, infection, and other systemic involvement, these patients are living longer, thus increasing the potential for surgical needs. Whether it is for routine surgeries or surgeries that are due to the natural history of the disease; the pediatric anesthesiologist must be knowledgeable of the management of these patients in order to prevent morbidity and mortality.

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Poor Sensitivity of Physician Assessment to Predict Acute Chest Syndrome in Children with Sickle Cell Disease and Fever

Blood ◽

10.1182/blood.v126.23.2185.2185 ◽

2015 ◽

Vol 126 (23) ◽

pp. 2185-2185

Author(s):

Stephanie G. Cohen ◽

Robert Hagbom ◽

Sarah G. Lazarus ◽

Courtney E. McCracken ◽

Olufolake A. Adisa ◽

...

Keyword(s):

Sickle Cell Disease ◽

Sickle Cell ◽

Clinical Assessment ◽

Clinical Course ◽

Normal Lung ◽

Acute Chest Syndrome ◽

Clinical Impression ◽

Cell Disease ◽

Physician Assessment ◽

History Of

Abstract Background: Acute chest syndrome (ACS) is a common complication of sickle cell disease (SCD) detected by chest radiography (CXR) with significant morbidity and mortality. Previous studies show that many children with ACS present without obvious signs or symptoms. We evaluate the sensitivity of clinical assessment for predicting ACS in children with SCD and fever. Methods: This is a prospective cross-sectional, observational study that took place from June 2014-March 2015. Consented providers in 2 CHOA EDs caring for patients aged 0-18 years with SCD and fever 38.0 C completed a questionnaire including vital signs, past history of ACS or asthma, clinical signs, symptoms, physical exam (PE) findings and whether the provider suspected pneumonia/ACS on CXR. CXRs were read by a blinded pediatric radiologist. CXR results were compared to questionnaire responses completed prior to CXR. Sensitivity, specificity, positive and negative predictive value and accuracy of clinical assessment for predicting ACS compared to CXR was determined. Signs, symptoms, PE findings, and clinical course was compared in cases with positive versus negative CXRs as well as suspected versus unsuspected ACS. Results: 111 SCD fever events with CXR were evaluated over 10 months. Thirteen patients (12%) had evidence of ACS on CXR. Based on MD questionnaires, only 46% of ACS cases were predicted by clinical assessment alone. Physician assessment sensitivity to identify ACS was low at only 50%. (Table 1). An abnormal lung exam, history of ACS, lack of rhinorrhea and a trend towards chest pain were more common in ACS cases compared to children with a negative CXR. However, 62% of children with ACS had a normal lung exam. Cases of unsuspected ACS had a lower degree of fever at presentation to the ED, but ultimately required more packed red blood cell transfusions during hospitalization than suspected ACS cases. There were no other significant differences in signs, symptoms, PE findings or clinical course in suspected vs. unsuspected ACS cases. The recently published NIH guidelines for including CXR in a fever work-up for children with SCD (risks include presence of cough, tachypnea, shortness of breath or abnormal lung exam) performed poorly in our cohort, with an Area under the Curve (AUC) = 0.725 Conclusions: Clinical impression alone is a poor predictor of ACS in children with SCD and fever. We and others have identified clinical criteria to help identify a high risk group, however many children with ACS lack signs and symptoms of ACS and may be missed based on clinical assessment alone. Given the high mortality and morbidity associated with ACS, empiric CXR may still be indicated in children with SCD. Due to radiation exposure risks with CXR, our team is studying lung ultrasound as an alternative modality for ACS imaging. Disclosures No relevant conflicts of interest to declare.

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To Give or Not to Give: RhD Immunoglobulin for an RHD*39 Pregnant Woman with Sickle Cell Disease

Transfusion Medicine and Hemotherapy ◽

10.1159/000512644 ◽

2021 ◽

pp. 1-5

Author(s):

Justin E. Juskewitch ◽

Craig D. Tauscher ◽

Sheila K. Moldenhauer ◽

Jennifer E. Schieber ◽

Eapen K. Jacob ◽

...

Keyword(s):

Pregnant Woman ◽

Sickle Cell Disease ◽

Sickle Cell ◽

Pregnancy Termination ◽

Acute Chest Syndrome ◽

Cell Disease ◽

Childbearing Age ◽

Procedural Complications ◽

History Of ◽

Chronic Hemolysis

Introduction: Patients with sickle cell disease (SCD) have repeated episodes of red blood cell (RBC) sickling and microvascular occlusion that manifest as pain crises, acute chest syndrome, and chronic hemolysis. These clinical sequelae usually increase during pregnancy. Given the racial distribution of SCD, patients with SCD are also more likely to have rarer RBC antigen genotypes than RBC donor populations. We present the management and clinical outcome of a 21-year-old pregnant woman with SCD and an RHD*39 (RhD[S103P], G-negative) variant. Case Presentation: Ms. S is B positive with a reported history of anti-D, anti-C, and anti-E alloantibodies (anti-G testing unknown). Genetic testing revealed both an RHD*39 and homozygous partial RHCE*ceVS.02 genotype. Absorption/elution testing confirmed the presence of anti-G, anti-C, and anti-E alloantibodies but could not definitively determine the presence/absence of an anti-D alloantibody. Ms. S desired to undergo elective pregnancy termination and the need for postprocedural RhD immunoglobulin (RhIG) was posed. Given that only the G antigen site is changed in an RHD*39 genotype and the potential risk of RhIG triggering a hyperhemolytic episode in an SCD patient, RhIG was not administered. There were no procedural complications. Follow-up testing at 10 weeks showed no increase in RBC alloantibody strength. Discussion/Conclusion: Ms. S represents a rare RHD*39 and partial RHCE*ceVS.02 genotype which did not further alloimmunize in the absence of RhIG administration. Her case also highlights the importance of routine anti-G alloantibody testing in women of childbearing age with apparent anti-D and anti-C alloantibodies.

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Hydroxyurea Treatment for Sickle Cell Disease

The Scientific World JOURNAL ◽

10.1100/tsw.2002.295 ◽

2002 ◽

Vol 2 ◽

pp. 1706-1728 ◽

Cited By ~ 13

Author(s):

Martin H. Steinberg

Keyword(s):

Sickle Cell Disease ◽

Sickle Cell ◽

Fetal Hemoglobin ◽

Hemoglobin Concentration ◽

Pharmacologic Therapy ◽

Acute Chest Syndrome ◽

Cell Disease ◽

Globin Chains ◽

Hydroxyurea Treatment ◽

Erythroid Precursors

High fetal hemoglobin (HbF) levels inhibit the polymerization of sickle hemoglobin (HbS) and reduce the complications of sickle cell disease. Pharmacologic agents that can reverse the switch from γ- to β-chain synthesis — γ-globin chains characterize HbF, and sickle β-globin chains are present in HbS — or selectively increase the proportion of adult erythroid precursors that maintain the ability to produce HbF are therapeutically useful. Hydroxyurea promotes HbF production by perturbing the maturation of erythroid precursors. This treatment increases the total hemoglobin concentration, reduces the vaso-occlusive complications of pain and acute chest syndrome, and attenuates mortality in adults. It is a promising beginning for pharmacologic therapy of sickle cell disease. Still, its effects are inconsistent, trials in infants and children are ongoing, and its ultimate value — and peril — when started early in life are still unknown.

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ANTXR1 Intronic Variants Are Associated with Fetal Hemoglobin in the Arab-Indian Haplotype of Sickle Cell Disease

Acta Haematologica ◽

10.1159/000491688 ◽

2018 ◽

Vol 140 (1) ◽

pp. 55-59 ◽

Cited By ~ 4

Author(s):

Zhara A. Al-Ali ◽

Rana K. Fallatah ◽

Esra A. Aljaffer ◽

Eman R. Albukhari ◽

Neriman Sadek Al-Ali ◽

...

Keyword(s):

Sickle Cell Disease ◽

Sickle Cell ◽

Sickle Cell Anemia ◽

Real Time Pcr ◽

Genetic Variants ◽

Fetal Hemoglobin ◽

Genetic Mutations ◽

Cell Disease ◽

Hbf Level ◽

Intronic Variants

Disease severity of sickle cell anemia is highly variable, and it is commonly accepted that fetal hemoglobin (HbF) levels play a major role as an ameliorating factor. Investigation of genetic variants have identified several genes to be the principal influencers of HbF regulation. Here, we further elucidated the association of rs4527238 and rs35685045 of ANTXR1 genes in the context of HbF level variance in sickle cell anemia patients of the Arab-Indian haplotype. Samples from 630 sickle cell anemia patients were analyzed for the mutations at 2 specific locations of the ANTXR1 gene by TaqMan®-based real-time PCR. The CC genotype (p = 0.018) of rs4527238 and the TT genotype (p = 0.048) of rs35685045 of ANTXR1 were found to be significantly associated with low HbF expression. The frequency of the CC genotype of rs4527238 was observed to be high in the low HbF patient group compared to the high HbF group (p = 0.009). Likewise, the frequency of the TT genotype of rs35685045 was also high among the low HbF group (p = 0.017). The ANTXR1 genetic mutations and the association with HbF expression in the Arab-Indian haplotype sickle cell patients revealed that the ANTXR1 gene may be a major HbF modulator leading to potential therapeutic options that should be further explored.

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Sickle crisis in the critically ill

10.1093/med/9780199600830.003.0275 ◽

2016 ◽

Author(s):

Shilpa Jain ◽

Mark T. Gladwin

Keyword(s):

Sickle Cell Disease ◽

Blood Cell ◽

Sickle Cell ◽

Red Blood Cell ◽

Systemic Infection ◽

Red Blood Cell Transfusion ◽

Acute Chest Syndrome ◽

Cell Disease ◽

Ischaemia Reperfusion Injury ◽

Transfusion Therapy

Sickle cell disease crises are precipitated by an acute occlusion of microvessels, which can lead to end organ ischaemia reperfusion injury and acute haemolysis. Acute fat emboli syndrome, acute lung injury (the acute chest syndrome), acute pulmonary hypertension, and cor pulmonale, haemorrhagic and occlusive stroke, and systemic infection represent the most common life-threatening complications observed in current ICU practice. General principles of management in all patients admitted to the critical care unit are hydration, antibiotics, pain control, and maintenance of oxygenation and ventilation. Red blood cell transfusion therapy is the treatment of choice for most complications of sickle cell disease requiring intensive care management. Transfusion of sickle negative, leukoreduced red blood cells, phenotypically matched for Rhesus and Kell antigens is the minimum standard of care in sickle cell disease patients as they have a high incidence of red blood cell alloimmunization.

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Sickle Cell Anemia

10.1093/med/9780199937837.003.0079 ◽

2017 ◽

Author(s):

Eboni I Lance ◽

Andrew W. Zimmerman

Keyword(s):

Sickle Cell Disease ◽

Sickle Cell ◽

Blood Cells ◽

Marrow Transplant ◽

Neurologic Complications ◽

Cell Disease ◽

Transfusion Therapy ◽

Hematological Disorder ◽

History Of ◽

Underlying Mechanisms

Sickle cell disease is a genetic hematological disorder involving red blood cells that become deformed when stressed. Patients with homozygous hemoglobin SS disease often have multiple systemic and neurologic complications, particularly stroke. Intellectual disability is commonly seen in the population, in patients with and without a history of stroke, attributed to different underlying mechanisms of brain injury. Autism is rare and not described in sickle cell disease in the literature to date. Many treatments (chronic transfusion therapy, hydroxyurea, bone marrow transplant) are in trials at this time to see if risk of stroke and other neurologic complications can be reduced (ClinicalTrials.gov identifiers: NCT01425307, NCT01389024, NCT00152113).

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Clinical events in the first decade in a cohort of infants with sickle cell disease. Cooperative Study of Sickle Cell Disease [see comments]

Blood ◽

10.1182/blood.v86.2.776.bloodjournal862776 ◽

1995 ◽

Vol 86 (2) ◽

pp. 776-783 ◽

Cited By ~ 321

Author(s):

FM Gill ◽

LA Sleeper ◽

SJ Weiner ◽

AK Brown ◽

R Bellevue ◽

...

Keyword(s):

Sickle Cell Disease ◽

Sickle Cell ◽

Clinical Course ◽

The United States ◽

Beta Thalassemia ◽

Acute Chest Syndrome ◽

Cooperative Study ◽

Cell Disease ◽

Splenic Sequestration ◽

Clinical Events

Within the Cooperative Study of Sickle Cell Disease, 694 infants with confirmed sickle cell disease were enrolled at less than 6 months of age. Information about the nature and frequency of complications was collected prospectively over a 10-year period. Painful crises and acute chest syndrome were the most common sickle cell-related events in homozygous sickle cell anemia (SS), hemoglobin SC disease (SC), and S beta thalassemia patients (overall incidence in SS patients of 32.4 and 24.5 cases per 100 person-years, respectively). Bacteremia occurred most frequently in SS children under 4 years of age and in SC patients less than 2 years of age. The mortality rate was low in this cohort compared with that found in previous reports. Twenty children, all with Hb SS, died (1.1 deaths per 100 person-years among SS patients). Infection, most commonly with Streptococcus pneumoniae and Hemophilus influenzae, caused 11 deaths. Two children died of splenic sequestration, 1 of cerebrovascular accident, and 6 of unclear causes. Two patients underwent cholecystectomies, and 17 underwent splenectomies after one or more splenic sequestration crises. The experience of this cohort should reflect closely the true clinical course of those children with Hb SS and Hb SC disease who are observed in sickle cell centers in the United States.

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An Evidence-Based Approach to the Treatment of Adults with Sickle Cell Disease

Hematology ◽

10.1182/asheducation-2005.1.58 ◽

2005 ◽

Vol 2005 (1) ◽

pp. 58-65 ◽

Cited By ~ 50

Author(s):

Richard Lottenberg ◽

Kathryn L. Hassell

Keyword(s):

Sickle Cell Disease ◽

Sickle Cell ◽

Enzyme Inhibitor ◽

Controlled Trial ◽

Acute Chest Syndrome ◽

Evidence Based ◽

Clinical Expertise ◽

Cell Disease ◽

Transfusion Therapy ◽

Treatment And Prevention

Abstract The application of evidence-based medicine to the management of adults with sickle cell disease (SCD) is currently primarily driven by clinical expertise and patient preference, as there is a paucity of randomized controlled trial (RCT) data to guide decision-making. A summary of SCD management principles in the areas of health care maintenance, transfusion therapy, treatment and prevention of painful episodes, acute chest syndrome, stroke, renal disease, contraception and pregnancy, and priapism is predominantly based on the authors’ interpretation of available observational studies as well as the opinions of experts in SCD. RCTs impacting current practices address use of hydroxyurea to prevent painful episodes and acute chest syndrome, intensity of pre-operative transfusion, transfusion during pregnancy, and angiotensin-converting enzyme inhibitor therapy for proteinuria, but most issues in adult SCD care have not been rigorously studied and management may not be appropriately extrapolated from pediatric data. While challenging clinical problems need to be addressed by RCTs, there is also the need for development of practice guidelines using formal methodological strategies. This brief review is not a substitute for the process but provides a literature-based approach to making treatment decisions when caring for adults with SCD.

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