Doctor with SCD patient

Credit: St Jude Children’s

Research Hospital

A new set of guidelines includes some strong recommendations for managing patients with sickle cell disease (SCD) that are not supported by high-quality evidence, according to researchers.

The group reviewed the medical literature to examine the quality of evidence supporting each of the guideline’s recommendations.

And they discovered a lack of randomized controlled trials in SCD patients that have left “extensive” gaps in our knowledge of the disease.

So while the guidelines do provide some helpful advice for managing patients with SCD, they also leave healthcare professionals with some uncertainties, according to the researchers.

The National Heart, Lung, and Blood Institute convened an expert panel to develop the guidelines, which are now available on the institute’s website.

Barbara P. Yawn, MD, of the Olmsted Medical Center in Rochester, Minnesota, and her colleagues examined the quality of evidence supporting the guidelines and reported their results in JAMA alongside a related editorial. Several examples of guideline recommendations and supporting evidence follow.

Health management recommendations

The guidelines strongly recommend oral penicillin prophylaxis twice daily until age 5 years in all children with HbSS to prevent invasive pneumococcal infection. And this recommendation is supported by moderate-quality evidence.

But the guidelines also strongly recommend referral to an ophthalmologist for dilated eye examination to screen for retinopathy beginning at age 10 years, and the quality of evidence supporting this recommendation is poor.

Acute SCD complications

The guidelines strongly recommend rapid initiation of parenteral opioids in adults and children with a vaso-occlusive crisis associated with severe pain, a suggestion supported by high-quality evidence.

However, the guidelines also strongly recommend treating SCD patients with acute chest syndrome with an intravenous cephalosporin, an oral macrolide antibiotic, and supplemental oxygen (to maintain oxygen saturation of >95%), as well as closely monitoring patients for bronchospasm, acute anemia, and hypoxemia. And this is supported by low-quality evidence.

Chronic complications

A strong recommendation supported by high-quality evidence is to treat avascular necrosis with analgesics and consult physical therapy and orthopedic departments for assessment and follow-up.

A strong recommendation supported by low-quality evidence is to evaluate all children and adults with SCD and intermittent or chronic hip pain for avascular necrosis by history, physical examination, radiography, and magnetic resonance imaging, as needed.

Use of hydroxyurea

Dr Yawn and her colleagues found that strong recommendations for hydroxyurea are all supported by moderate- or high-quality evidence.

A strong recommendation supported by high-quality evidence is to initiate hydroxyurea in adults who have at least 3 moderate-to-severe pain crises associated with SCD during a 12-month period.

A strong recommendation supported by moderate-quality evidence is to initiate hydroxyurea in adults who have sickle cell-associated pain that interferes with daily activities and quality of life.

Transfusion therapy

For this category, the only strong recommendation supported by high-quality evidence is to transfuse a child with a transcranial Doppler reading greater than 200 cm/s.

The guidelines strongly recommend transfusing red blood cells in adults and children with SCD to bring the hemoglobin level to 10 g/dL prior to undergoing a surgical procedure involving general anesthesia, but this is supported by moderate-quality evidence.

A strong recommendation supported by low-quality evidence is to perform an exchange transfusion in a patient with symptomatic, severe acute chest syndrome (defined by an oxygen saturation less than 90% despite supplemental oxygen).

Conclusions

Dr Yawn and her colleagues said this investigation confirms that developing guidelines for managing SCD is challenging because high-quality evidence is limited in virtually every area related to SCD management.

Therefore, the guidelines leave healthcare professionals with some uncertainties about managing SCD patients. But the researchers hope their analysis will prompt new research that might provide more definitive guidance.

Recommendations for managing SCD lack supporting evidence