DANVILLE —With Sickle Cell Awareness Day coming up on June 19, Valley doctors want to get the word out about the genetic disease that can cause debilitating pain due to deficient red blood cells.
“Sickle cell anemia is a type of inherited blood disorder in which there aren’t enough healthy red blood cells,” said Dr. Priyanka Pathak, a hematologist oncologist with the Geisinger Health System. “Normally, red blood cells, which carry oxygen throughout the body, are round and flexible which enables them to pass through the smallest blood vessels in the body. In sickle cell anemia, these cells take on a sickle or crescent shape and become inflexible. This causes them to get stuck in the blood vessels which prevents different parts of the body from getting enough oxygen.”
Dr. Enrico Novelli, a hematologist, UPMC Hillman Cancer Center, and director of the UPMC Adult Sickle Cell Anemia Program, said the symptoms of the disease manifest in infancy, and the disease requires both parents to pass down the gene that causes sickle cell.
“Sickle cells do not survive as long as normal red blood cells, causing anemia,” Novelli said. “It is important to note that it is necessary to inherit two mutated hemoglobin genes to have sickle cell anemia. People who only carry one mutated gene are generally healthy.”
According to Novelli, thanks to modern screening techniques many children in the U.S. are diagnosed at birth. The most common and oldest test is hemoglobin electrophoresis, which measures the different types of hemoglobin in the blood and looks for abnormalities.
Abnormalities like sickle cells can cause severe fatigue and pain occur as early as five to six months of age, Pathak said.
“The children can have episodes of severe pain all over the body.” Pathak said. “They can get swelling of the hands and feet, vision problems, delayed growth and frequent infections. Silent strokes can happen in childhood as well.”
Novelli calls these sever pain episodes “pain crisis.” Patients may seem to be doing well one day and then incredibly sick the next. This can happen when “the sickle cells and other blood cells becoming very sticky and attaching to the wall of the blood vessels causing blockages,” he said. “Blood cannot be delivered downstream of the blockages causing severe bouts of pain and damage to the tissues and organs of the body.”
Another debilitating aspect of the disease is organ failure, which can occur as patients age. Novelli said some can end up on dialysis due to kidney damage.
Pathak also said the African American population in the United States is the most likely to inherit the disease.
Novelli noted other cultural genetic possibilities.
“Most people affected with sickle cell anemia live in sub-Saharan Africa and India, although due to migrations and displacement of people throughout history, the disease can be found in many parts of the world. In the United States, sickle cell anemia is predominantly found among Black people, although people from Latin America, Southern Europe (e.g. Italy and Greece), India and the Arab peninsula among others can also carry the gene and the disease.”
Treatment is centered around maintaining control of the pain. While some drugs are available, the treatment options are few.
The method is about “relieving symptoms when they occur and preventing complications,” Pathak said, listing medications such as Hydroxyurea, L-Glutamine, Crizanlizumab and Voxelotor.
Novelli said there is no guarantee of permanent removal of pain with the medications.
“None of them is a cure but they help mitigating the effects of sickle cell anemia and improving quality of life. In addition, antibiotics are very important to prevent infections in children, and transfusions improve the anemia and the risk of stroke.”
Novelli said before medications were available, many children died of the disease before reaching adulthood.
“Unfortunately, this is still the case in poor countries across the world,” Novelli said.
“Stem cell transplant,” Pathaki said, “is the only cure for sickle cell anemia.”
Novelli explained that stem cell therapy requires chemotherapy, radiation and a matched donor.
“With stem cell transplantation, normal parent cells (stem or progenitor cells) of all the cells of the blood, including red blood cells, can be transplanted from a healthy donor (ideally a fully matched sibling) to a person with sickle cell anemia, curing her from the disease,” Novelli said.
A new treatment is being studied, Novelli said, known as gene therapy.
“Genes can be inserted or removed from the stem cells of a person living with sickle cell anemia, potentially curing their disease. Gene therapy holds great promise, but currently it is only available in research studies,” Novelli said.