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Dr. Andrew Campbell examines a child

Children’s National physicians provide education at 46th Annual Sickle Cell Disease Association of America Convention

Dr. Andrew Campbell examines a child

Andrew Campbell, M.D., presented at the conference on the topics of hydroxyurea (HU) and blood transfusions.

More than 600 researchers, physicians, nurses, social workers and individuals living with sickle cell disease (SCD) and sickle cell trait (SCT) gathered in Baltimore for the 46th Annual National Sickle Cell Disease Association of America (SCDAA) Convention in mid-October. Children’s National physicians Andrew Campbell, M.D., director of the Comprehensive Sickle Cell Program, and Deepika Darbari, M.D., were among the speakers at the four-day convention discussing the latest scientific research and clinical information through seminars, panel discussions and symposiums.

Dr. Campbell presented at the conference on the topics of hydroxyurea (HU) and blood transfusions. He spoke to families about the benefits of HU, explaining how it lowers the percentage of sickle cells in the blood and decreases the overall inflammatory process. He stressed the importance of HU as a medication used in the prevention of SCD and emphasized the potential decrease in organ damage and increased overall survival rate of SCD patients. The importance of minor antigen blood group phenotyping was also discussed, as it can decrease the chance of patients rejecting future blood transfusions by developing new red blood cell antibodies.

“The indications for blood transfusions in the acute ‘ill’ setting can be life-saving and improve oxygen delivery and overall clinical outcomes within sickle cell complications, including acute chest syndrome, stroke and splenic sequestration. Approximately 10 to 15 percent of patients will need monthly blood transfusions for primary (i.e. stroke, patients with abnormal brain vessel TCD velocities >200cm/s) and secondary (i.e. patients with a previous stroke, multiple splenic sequestrations, recurrent priapism, recurrent acute chest syndromes) sickle cell complications,” explains Dr. Campbell.

Dr. Darbari, a hematologist at Children’s National, educated medical colleagues on chronic pain in SCD and emphasized the increase in pain from adolescence to adulthood.

“During childhood, pain in SCD is considered a consequence of discrete episodes of vaso-occlusion.  Such vaso-occlusion is a complex process in which abnormally shaped (so-called ‘sickled’) red blood cells episodically obstruct the microcirculation thereby causing distal ischemia and resultant pain. As patients get older, mechanisms such as peripheral neuropathic or centralization may play important roles in transition and maintenance of chronic pain. It is important to consider underlying mechanisms contributing to pain when managing a patient with SCD,” states Dr. Darbari. She referenced her coauthored and published Analgesic, Anesthetic and Addiction Clinical Trial Translations Innovations Opportunities and Networks (ACTTION)-American Pain Society Taxonomy (AAPT) criteria for classifying chronic pain in SCD and how useful this tool can be for physicians in the treatment of patients with SCD.

Both Drs. Campbell and Darbari shared their expertise on different facets of SCD with families and medical professionals alike. Their impactful work is paving the way for future treatments and pain management techniques for treating patients living with SCD and their families.

Blood Transfusion

Hydroxycarbamide effective in sickle cell stroke prevention

Blood Transfusion

Hydroxycarbamide treatment is on par with blood transfusions for preventing stroke in patients with sickle cell anemia.

What’s known

Strokes are common and devastating complications for patients with sickle cell anemia, often leading to severe and lifelong motor and neurocognitive problems for people with this congenital blood disorder. Results of a clinical trial published in 1998 showed that having regular blood transfusions could reduce the risk of having a first stroke by 90 percent in children with sickle cell anemia. Since then, doctors have employed this prophylactic treatment widely. However, blood transfusions can be painful, inconvenient and carry substantial risks themselves — including the potential of blood-borne infections, iron overload and immune-related reactions to blood products. Finding a way to reduce stroke risk without over-relying on blood transfusions could substantially benefit patients with sickle cell anemia.

What’s new

A team of researchers, including Naomi L.C. Luban, M.D., a Children’s National Health System hematologist and laboratory medicine specialist, tested transfusions against a drug treatment called hydroxycarbamide in a clinical trial to see if the pharmaceutical intervention could reduce strokes at least as well as transfusions. The clinical trial, known as “TCD With Transfusions Changing to Hydroxyurea (TWiTCH),” assigned 60 patients with sickle cell anemia who had abnormally high transcranial Doppler (TCD) flow velocities—a measure of blood flow in the brain that suggests elevated risk of stroke—to receive hydroxycarbamide instead of transfusions. The research team compared the outcomes for these patients with 61 other patients who received standard prophylactic transfusions. Over the 24-month study period, neither group experienced any strokes, although three transient ischemic attacks (a temporary blockage of blood flow in the brain) occurred in each group. These comparable findings suggest that hydroxycarbamide treatment, also known as hydroxyurea, is on par with transfusions for preventing strokes in patients with sickle cell anemia.

Questions for future research

Q: Does hydroxycarbamide offer a long-term way for patients with sickle cell anemia to avoid transfusions?
Q: Could hydroxycarbamide help patients with sickle cell anemia who already have suffered a stroke or who have had severe problems with blood vessels in their brains that impair blood flow?
Q: Which other treatments can help patients avoid the myriad complications that accompany sickle cell anemia?

Source: Hydroxycarbamide versus chronic transfusion for maintenance of transcranial doppler flow velocities in children with sickle cell anemia—TCD With Transfusions Changing to Hydroxyurea (TWiTCH): A multicentre, open-label, phase 3, non-inferiority trial.” Ware, R.E. B. R. Davis, W. H. Schultz, R.C. Brown, B. Aygun, S. Sarnaik, I. Odame, B. Fuh, A. George, W. Owen, L. Luchtman-Jones, Z.R. Rogers, L. Hilliard, C. Gauger, C. Piccone, M.T. Lee, J.L. Kwiatkowski, S. Jackson, S.T. Miller, C. Roberts, M.M. Heeney, T.A. Kalfa, S. Nelson, H. Imran, K. Nottage, O. Alvarez, M. Rhodes, A.A. Thompson, J.A. Rothman, K.J. Helton, D. Roberts, J. Coleman, M.J. Bonner, A. Kutlar, N. Patel, J. Wood, L. Piller, P. Wei, J. Luden, N.A. Mortier, S.E. Stuber, N. L. C. Luban, A.R. Cohen, S. Pressel and R.J. Adams. Published by The Lancet on Feb. 13, 2016.