A patient on hydroxyurea for sickle cell disease who developed an opportunistic infection

Navigating the Diagnosis and Management of Rheumatoid Arthritis in the Context of Sickle Cell Disease: A Dual Challenge

Sickle cell disease is a common condition in the eastern part of India and can often present with pain crisis, vasculo-occlusive crisis and anemia. These patients seldom have coexisting rheumatological illnesses like rheumatoid arthritis that are camouflaged with the pain crisis of sickle cell disease, leading to a delay in the diagnosis and a delay in initiating the treatment which leads to a poorer quality of life. Herein we discuss a case of sickle cell disease presenting concomitantly with the features of rheumatoid arthritis and the challenges faced in the diagnosis and treatment.

Rheumatoid Arthritis in Sickle-Cell Population: Pathophysiologic Insights, Clinical Evaluation and Management

The advent of hydroxyurea and advanced medical care, including immunizations has led to improved survival among patients with Sickle Cell Disease (SCD). This prolonged survival however, introduces a chronic inflammatory disorder, Rheumatoid Arthritis (RA), which presents at a relatively older age and is rarely reported among SCD patients. In this review, we highlight the epidemiological association of SCD-RA and discuss the underlying common pathogenetic mechanisms, such as endothelial dysfunction, the role of inflammatory cytokines and oxidative stress. We also point to the difficulties in ascertaining the clinical diagnosis of RA in SCD patients. Finally, we provide rationale for therapeutic options available for RA and the challenges in the management of these patients with agents that are known to increase the risk of infection and immunosuppression such as steroids, disease modifying anti-rheumatic drugs and biologics.

Systematic review: Hydroxyurea for the treatment of adults with sickle cell disease

BACKGROUND

Hydroxyurea is the only approved drug for treatment of sickle cell disease.

OBJECTIVE

To synthesize the published literature on the efficacy, effectiveness, and toxicity of hydroxyurea when used in adults with sickle cell disease.

DATA SOURCES

MEDLINE, EMBASE, TOXLine, and CINAHL were searched through 30 June 2007.

STUDY SELECTION

Randomized trials, observational studies, and case reports evaluating efficacy and toxicity of hydroxyurea in adults with sickle cell disease, and toxicity studies of hydroxyurea in other conditions that were published in English.

DATA EXTRACTION

Paired reviewers abstracted data on study design, patient characteristics, and outcomes sequentially and did quality assessments independently.

DATA SYNTHESIS

In the single randomized trial, the hemoglobin level was higher in hydroxyurea recipients than placebo recipients after 2 years (difference, 6 g/L), as was fetal hemoglobin (absolute difference, 3.2%). The median number of painful crises was 44% lower than in the placebo group. The 12 observational studies that enrolled adults reported a relative increase in fetal hemoglobin of 4% to 20% and a relative reduction in crisis rates by 68% to 84%. Hospital admissions declined by 18% to 32%. The evidence suggests that hydroxyurea may impair spermatogenesis. Limited evidence indicates that hydroxyurea treatment in adults with sickle cell disease is not associated with leukemia. Likewise, limited evidence suggests that hydroxyurea and leg ulcers are not associated in patients with sickle cell disease, and evidence is insufficient to estimate the risk for skin neoplasms, although these outcomes can be attributed to hydroxyurea in other conditions.

LIMITATION

Only English-language articles were included, and some studies were of lower quality.

CONCLUSION

Hydroxyurea has demonstrated efficacy in adults with sickle cell disease. The paucity of long-term studies limits conclusions about toxicity.

Systematic review: Hydroxyurea for the treatment of adults with sickle cell disease

BACKGROUND

Hydroxyurea is the only approved drug for treatment of sickle cell disease.

OBJECTIVE

To synthesize the published literature on the efficacy, effectiveness, and toxicity of hydroxyurea when used in adults with sickle cell disease.

DATA SOURCES

MEDLINE, EMBASE, TOXLine, and CINAHL were searched through 30 June 2007.

STUDY SELECTION

Randomized trials, observational studies, and case reports evaluating efficacy and toxicity of hydroxyurea in adults with sickle cell disease, and toxicity studies of hydroxyurea in other conditions that were published in English.

DATA EXTRACTION

Paired reviewers abstracted data on study design, patient characteristics, and outcomes sequentially and did quality assessments independently.

DATA SYNTHESIS

In the single randomized trial, the hemoglobin level was higher in hydroxyurea recipients than placebo recipients after 2 years (difference, 6 g/L), as was fetal hemoglobin (absolute difference, 3.2%). The median number of painful crises was 44% lower than in the placebo group. The 12 observational studies that enrolled adults reported a relative increase in fetal hemoglobin of 4% to 20% and a relative reduction in crisis rates by 68% to 84%. Hospital admissions declined by 18% to 32%. The evidence suggests that hydroxyurea may impair spermatogenesis. Limited evidence indicates that hydroxyurea treatment in adults with sickle cell disease is not associated with leukemia. Likewise, limited evidence suggests that hydroxyurea and leg ulcers are not associated in patients with sickle cell disease, and evidence is insufficient to estimate the risk for skin neoplasms, although these outcomes can be attributed to hydroxyurea in other conditions.

LIMITATION

Only English-language articles were included, and some studies were of lower quality.

CONCLUSION

Hydroxyurea has demonstrated efficacy in adults with sickle cell disease. The paucity of long-term studies limits conclusions about toxicity.

[Hydroxyurea treatment in patients affected with sickle cell anemia: efficacy and safety]

Hydroxyurea is the unique drug having demonstrated an efficacy in preventing recurrences of painful crises, acute chest syndromes and in reducing transfusional needs in patients severely affected with sickle cell disease. However, there is a wide variation in the clinical response to hydroxyurea in sickle cell patients, with children generally experiencing greater benefits than adults. Short- and middle-term tolerances are good. Our uncertainties about long-term tolerance are mainly that we do not know the consequences of the drug on ulterior fertility in boys treated early and for long periods. Hydroxyurea has just been licensed for sickle cell adults and children in Europe. Its prescription for the moment must be restricted to severely affected patients, enrolled in long-term follow-up protocols.

Disseminated nontuberculous mycobacterial infections in sickle cell anemia patients

Nontuberculous mycobacteria (NTM) are ubiquitous in nature and have been implicated in skin/soft-tissue, pulmonary, middle ear, bone, and surgical/traumatic wound infections. Disseminated disease occurs infrequently and almost exclusively in the immunocompromised. We describe the first 2 reported cases of disseminated Mycobacterium fortuitum infection in teenagers with sickle hemoglobinopathy. Both had central venous catheters (CVCs), frequent admissions for vaso-occlusive painful episode and received hydroxyurea. Diagnosis was confirmed by multiple positive blood cultures and pulmonary dissemination occurred in both. Both had successful treatment after CVC removal and combination drug therapy. Positive cultures persisted in 1 patient due to drug resistance emphasizing the need for accurate susceptibility data. NTM infection should be added to the list of pathogens in sickle cell patients with CVCs and fever. Investigation for disseminated disease should be undertaken based on clinical signs and symptoms. Although some routine blood culture systems can identify NTM, specific mycobacterial blood culture is optimal. Removal of involved CVCs is essential and treatment of NTM must be guided by susceptibilities. As dissemination almost always occurs in those with impaired cellular immunity, human immunodeficiency virus testing should be performed. Hydroxyurea may be a risk factor for dissemination and needs further evaluation.