Researcher says sickle cell patients shouldn’t lose vision

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By Marie Y. Lemelle

Contributing Writer

According to the Centers of Prevention and Disease Control, there are millions of people living with sickle cell disease and one out of every 365 Black babies is affected with the disease.

The sickle cell trait, which is not a disease, is inherited from one or both parents and affects about one in 13 Black babies. About 3 million people are living with the sickle cell trait and are unaware of it. Sickle cell trait is diagnosed with a simple blood test. People at risk of having it may talk with a doctor or health clinic about getting tested.

“I met Gail Woolley for retinal evaluation because she had sudden severe vision loss due to sickle cell disease related vitreous hemorrhage and retinal detachment after an ICU stay for complications from acute chest syndrome,” said Dr. Adrienne W. Scott, an associate professor of ophthalmology at the Wilmer Eye Institute at Johns Hopkins University School of Medicine.

She focuses on vitreoretinal diseases, with an emphasis on sickle cell retinopathy and its relationship to systemic sickle cell disease, retinal imaging and health disparities in eye care.

“As sickle cell disease primarily strikes individuals from Black and African descent and from more vulnerable socioeconomic backgrounds, Gail and her husband Howard Woolley were successful, well-traveled and affluent,” Scott said. “In spite of their social standing and education, Gail suffered the lifelong stigma well-known to sickle cell disease patients, where trips to the E.R. seeking relief from painful vaso-occlusive crises often meant unpleasant exchanges with E.R. physicians suspicious of drug-seeking patients; therefore, pain relief was often deferred and inadequate.”

Many patients with sickle cell disease avoid E.R. presentation even at times when they are in severe pain, for this reason, Scott said.

“Gail told me, ‘I have to see, I need my vision back so I can complete my memoir.’ Vitreoretinal surgery is challenging and sickle cell retinal detachment repair particularly so, complicated by the Gail’s systemic sickle morbidity with anesthesia risk,” Scott said. “Fortunately, I was able to repair the retinal detachment and save Gail’s sight.”

Scott says treating Gail in 2014 changed her health career research choice.

“I’m fortunate to be at Johns Hopkins and as I started my career on faculty, Dr. Mort Goldberg, for whom the sickle cell retinopathy grading system is named in the 1970s, was cutting back clinically,” Scott said. “I saw an opportunity to deepen our understanding of sickle cell retinopathy, in that new imaging modalities such as OCT angiography and ultra-wide field fluorescein angiography were providing more and more insight into retinal vascular disease.

“Sickle cell disease is an inherited blood disorder affecting red blood cells. Normal red blood cells contain hemoglobin A, which helps oxygen travel through the body,” Scott said. “People with sickle cell disease have red blood cells containing mostly hemoglobin S, or other abnormal types of hemoglobin. These red blood cells become sickle-shaped (crescent-shaped), and have difficulty passing through small blood vessels and getting oxygen to the tissues of the body. When there is lack of oxygen to the body from sickle cell disease, patients will feel pain.”

Acute chest syndrome, which is most often triggered by a respiratory infection is one of the sickle cell disease serious complications and major cause of death. People living with sickle cell disease are at risk for acute pulmonary complications, including viral infections.

“Individuals with sickle cell disease have a genetic mutation in their hemoglobin, the molecule responsible for transporting oxygen through the body,” said Scott, who is native to Washington, D.C., and a mother of three. “The retina is the nerve tissue that lines the back of the eye and helps us see. The retina has a high oxygen demand to function properly.  In sickle cell retinopathy, abnormal oxygen transport in the retina can in abnormal blood vessel growth and thinning of the retina. Though most individuals with sickle cell disease have good vision, in some individuals, sickle cell retinopathy can impair vision.”

Scott adds, “Anyone with sickle cell disease can develop sickle cell retinopathy, but it is more common in people with specific hemoglobin mutations, including sickle-hemoglobin C disease and sickle beta plus thalassemia.”

When lack of oxygen occurs to the retina, patients do not feel this and often experience no symptoms. However, when symptoms are present, patients describe blind spots, sudden onset of floaters or blurred vision, flashes of light, and loss of side vision or a shadow over their vision. These symptoms may be caused by a lack of blood flow to the retina; formation of new abnormal blood vessels which can burst or bleed; or retinal detachment which can result in significant vision loss.

Scott recommends a yearly sickle cell retinopathy screening exam with a retina specialist starting at age 10 for those diagnosed with sickle cell disease in order to monitor the condition and begin needed treatment as early as possible.

“Common treatments for advanced sickle cell retinopathy include laser treatment of large areas of blocked blood vessels, surgery and injections of medications that can prevent new blood vessel formation in select patients,” Scott said.

“Hemoglobin blood disorders like [sickle cell disease] can make you more likely to get severely ill from COVID-19,” she added. “According to the CDC, preventive measures such as vaccination, wearing a mask and social distancing are critically important for anyone with an underlying health condition like [sickle cell].”

The coronavirus also can trigger sickle cell disease complications.

Patients who have conditions often associated with sickle cell disease, are more vulnerable to COVID-19, such as hyper inflammation — when a body’s immune response goes out of control and begins attacking healthy cells; deep vein thrombosis — a blood clot, usually in the legs, but can also happen in the lungs and other veins, that can cause pain and/or swelling; immunocompromised state, having a weakened or impaired immune system to the point where your body cannot effectively fight infection; and life-threatening organ damage when tissues of the body of almost every organ system that are already weakened from lifelong damage from sickle cell disease.

The CDC designated sickle cell disease among the medical conditions with high risk for severe COVID-19, and currently, in most states, sickle cell disease is now considered one of the priority conditions for which vaccination is recommended. Trusted providers can play key roles in overcoming vaccine hesitancy, particularly in vulnerable populations.

Scott says sickle cell disease “is really the prototypical example of a racial health disparity. As we know, it is the most common inherited blood disorder, the first disease where an abnormal protein was identified to be at fault.”

Before Gail passed away from complications from pulmonary hypertension in 2015 at 58, she continued to be an accomplished woman. She finished her memoir and, along with her husband, championed Scott’s sickle cell retinopathy research program.

“I am forever grateful for the impact the Woolleys had on my life as a researcher to find solutions to stop vision loss for people with sickle cell,” Scott said.

Marie Y. Lemelle is the founder of www.platinumstarpr.com and a film producer. She can be reached at MarieLemelle@platinumstarpr.com. Follow her on Instagram @platinumstarpr.