What is Sickle cell disease?
Sickle cell anemia is a severe form of anemia caused by genetic mutation in the Red blood cells. It is a genetic disorder which is inherited by the patient from the two faulty hemoglobin genes from both the parents. Because of the genetic mutation,the shape of RBC ,which is flexible circular disc shaped changes to rigid sickle or crescent shaped rods. Hemoglobin a protein in RBCs,works as a transporter of nutrients and oxygen to cells all across the body.Normal RBCs are disc shaped,with the centers partially scooped out. They are flexible and soft and therefore have the capacity to squeeze through even the tiniest of blood vessels to reach every cell in the body.Due to genetic mutation the RBCs acquire the shape of a crescent moon or Sickle and become rigid and brittle.These Abnormal shaped RBCs which are not flexible get struck in small blood vessels causing slow or blockage of blood flow to other tissues of body and disrupt supply of Oxygen to those parts. Moreover the lifespan of abnormal sickle shaped RBCs is only 10-20 days as compared to 120 days of normal RBCs.Human body keeps on forming new RBCs to replace the old ones,but in a person with sickle cell disease the balance in formation of new RBCs and Destruction of existing RBCs is disturbed. This results in lower RBC count or anemia in a person suffering with Sickle cell disease.
What are complications of Sickle cell disease?
Sickle cell anemia may have different complications in different people at different stages of disease,but the major and severe complications for a person suffering from sickle cell anemia can be broadly classified as Acute and chronic.
Sickle cell crisis:
Sickle cell crisis or VAS ( Vaso occlusive crisis ) manifests as acute severe pain.Sickle cells disrupts blood supply through smaller capillaries resulting in ischemia. Sudden pain across body that may persist from a few hours to a few days.The pain usually occurs in limbs,chest and back.
Fever and infections:
Patients with sickle cell disease are prone to severe bacterial infections because of reduction or absence of splenic function. This may expose the patient to extremely high risk of septicemia and meningitis.Pneumonia is the most common infection ,meningitis,influenza and hepatitis are other infections occurring in sickle cell disease patients.
Sickle cell disease may cause a a stroke in an affected person because of oxygen deprivation due to blockage in supply of blood to tissue of brain. Some of the sickle cell anemia patients may experience a Transient ischemic attack.
Acute Chest Syndrome:
Pneumonia like complications in a child or adult suffering from sickle cell disease. The reason could be an infection or sickle cells trapped in micro capillaries of lungs.
Hepatobiliary tract abnormalities are common in sickle cell disease patients.They may include cholelithiasis, acute cholecystitis, biliary sludge, and acute choledocholithiasis,acute Hepatic Sequestration and acute intrahepatic cholestasis.
Acute renal failure:
A decrease in kidney functions due to dehydration or obstruction or even because of intrinsic renal disease.
May be because of Splenic sequestration.
Multisystem Organ failure:
A systemic failure of lungs,liver and kidney is a life threatening medical condition for sickle cell anemia patients.
A sickle cell disease patient may develop vision problems over a period of time.It may include proliferative sickle retinopathy and vitreous hemorrhage. Complete vision loss is also possible.
Avascular or aseptic necrosis can occur when capillaries are occluded by sickled erythrocytes at distal portions of a bone, near a joint, where hypoxia is maximal and collateral circulation is inadequate .The most common site for sickle cell anemia induced avascular necrosis is femoral neck.
Leg ulcers appear in patients of sickle cell anemia.
Pulmonary hypertension occur in sickle cell disease patients.
Sickle cell anemia-Treatments:
Sickle cell anemia patients are usually referred to a Hematologist ( A doctor who has specialized in blood disease management). Treatment of sickle cell anemia may involve determining many factors by the treating hematologist.Treatment of sickle cell anemia includes regular monitoring and follow up with a hematologist,Medications for management of symptoms and complications,pain management,blood transfusions, oxygen supplementation and allogeneic Bone Marrow transplant.
Stem Cell or BMT for Sickle cell disease
Stem cell or Bone marrow transplant is a viable treatment option for those young sickle cell anemia patients where the diseases condition is severe and can not be managed with conventional methods. A sickle cell anemia child who is having a matching sibling donor is referred for a bone marrow transplant by the hematologist considering all the pros and cons. Risk involved is big but a stem cell or bone marrow transplant is the only cure for sickle cell anemia child or young adult.
Before the transplant, bone marrow cells are taken from a close matching healthy brother or sister. The patient with sickle cell disease is then treated with chemotherapy and radiation that destroy his or her bone marrow cells. After that, the donated bone marrow stem cells are transplanted in the patient.