Sickle Cell disease is when red blood cells take an unusual shape and obstruct blood vessels, causing injury to several tissues.
An extended explanation of Sickle cell disease will be done in this article, the cause, the symptoms, and how it works. We’ll also be seeing about its complication, how to know if someone has it, and how to treat it.
By reading this article, you will get an insightful description of this common hereditary blood disease. Please continue reading to obtain comprehensible yet profound information about this disease, all explained by a doctor.
What is sickle cell disease?
Sickle cell disease is a hereditary and genetic disease that affects the red blood cells from birth. This is the most common heritable blood disease, affecting 70.000 to 100.000 people in the United States of America.
It is present mostly in people that have an ancestor from Africa, the Mediterranean, and Spain. In light of this, there is a high amount of sickle cell anemia cases, especially in South America and Africa, within the black population.
When a person carries the gene or the disease itself, they are immune to the Plasmodium’s disease, Malaria. Plasmodium is a parasite that introduces itself in healthy red blood cells, reproducing in them and then destroying them. This causes anemia, chronic fevers, and spleen bigger in size, making it a fatal disease that mosquitoes easily transmit. Therefore, professionals say that the sickle cell disease mutation is a product of the body’s defense mechanism in these zones where malaria is so widespread.
Red blood cells are in charge of transporting oxygen from the lungs to all tissues in the body. They also bring back carbon dioxide to the lungs, all of this with help from a protein in blood cells.
Hemoglobin is a necessary and complex protein inside of red blood cells that carry oxygen and carbon dioxide. In sickle cell disease, abnormal hemoglobin is made by the body, which causes the blood cell to take a C or sickle shape.
Normal red blood cells can move through the blood vessels without problems since they are quite flexible and elastic. Sickled cells, on the other hand, have issues passing through small blood vessels because of their shape and rigidity.
Since they present trouble going through, it can obstruct the blood flow to different organs and tissues. This blood blocking can cause pain, healthy tissue damage, and can also lead to infections.
What are the signs and symptoms of a sickle cell crisis?
Sickle cell disease can manifest itself in many different ways; one of those is acute pain when there’s a crisis. A vaso-occlusive crisis is when the sickle cells obstruct the blood vessels of the microcirculation, causing poor blood flow.
The decrease of blood going to the tissues leads to the area’s infarction (lack of blood), resulting in a sickle cell pain crisis. How often patients suffer from these crises varies, some have episodes up to six times a year and others none.
Usually, the frequency of the painful crises is consistent with each person, and they expect it in a particular pattern. It can start abruptly and last from hours to days, ending as suddenly as it began.
The low blood flow can happen in many parts of the body, producing infarction and pain in various characteristic places. One of these places is the abdomen since organ damage occurs very often, and the patient feels this pain diffusively.
Depending on the tissue’s extent within the infarction, it can produce severe pain, making it a common hospitalization cause. Another common site the disease causes injury is the bones, especially long bones such as the ones in the legs. Since the blood vessels that carry blood to these areas are small, it’s a frequent place the sickled cells obstruct. Also, sickle cell patients often present pain in the legs, joints, and spine when they are in their adolescence.
Hand-foot syndrome is also a common manifestation of sickle cell crisis in children between 6 months and three years old. It is the swelling and pain of the hands and feet soft tissue, called dactylitis, by doctors. This syndrome occurs because, between those ages, part of red blood cell production happens in the hands’ bones.
What triggers the sickle cell crisis?
There are multiple factors, known by doctors, that can precipitate a sickle cell patient crisis. The main factor is hypoxia, whether it is the product of an external cause of the environment or an internal cause. Hypoxia means having less oxygen in the blood that a person would typically have.
An example of an external cause is at places with low oxygen levels, such as high mountain peaks. An internal cause is having a respiratory infection that leads to a drop in red blood cells’ oxygen levels.
Dehydration can also trigger sickle cell crises, since the volume of fluid inside blood vessels decreases, making them smaller. When the blood vessels get smaller, there’re higher probabilities for a sickle cell to obstruct them, causing tissue damage.
In addition, acidosis causes problems in red blood cells’ normal function, as it alters oxygen’s uptake and holds. Acidosis happens when the blood pH gets lower because of severe infections, kidney problems, diarrhea, and many others.
Finally, some triggers are more common to find daily, such as cold temperatures, psychological stress, pregnancy, and alcohol intoxication. Cold weather induces the peripheral blood vessels to contract as it needs to preserve the body heat.
Which children are at risk for sickle cell disease?
Genetically there are diverse types of sickle cell disease, and they affect people differently. The kind of disease depends on which genes carry each parent, making some forms more hard-hitting than others.
The most common one is with two S globins (HbSS), meaning each parent carries the same S globin gene. It’s the most severe form of the disease as it has the lowest survival rate in most patients with SCD.
Another form is HbSC, in which the patient inherits one sickle cell gene (Hemoglobin S) and one hemoglobin C gene. The latter is an abnormal hemoglobin form, and both together make a minor or less severe disease type.
Furthermore, with HbS beta-thalassemia, one parent has an HbS gene, and the other a gene for beta-thalassemia. This is not a very common disease. Also, there are different kinds of beta-thalassemia: 0 and +. The 0 type is a more severe one, while the + type is a milder version of the disease.
When a person carries the gene but does not develop the disease, it’s what doctors call a sickle cell trait. These patients have mostly normal hemoglobin and do not show any problems throughout their lives unless they’re under severe hypoxia. But they can also pass the gene to their child, exposing them to the risk of suffering from SCD.
Although these different subtypes prone patients to varying levels of risks, the most significant threat is a lack of education. When people who suffer from SCD and have a low economic and social status, there are more chances they don’t take care of themselves. This situation exposes them to other diseases and poor lifestyle choices that only worsen the condition.
Why does sickle cell disease cause health problems?
When the body exposes red blood cells in sickle cell patients to situations of poor oxygen or low oxygen levels, these take a sickled form. This form can be reversible, but they become an irreversible sickle cell after several times of exposure.
Many sickle cells obstruct the small blood vessels since they cannot pass, as they have now become rigid. Low blood flow to the tissue can lead to a permanent injury and dysfunction of the particular organ.
Besides, the patient also suffers from hemolytic anemia, which is when red blood cells die prematurely inside blood vessels. Hemoglobin’s massive production to the blood causes a depletion of nitric oxide, a molecule that widens blood vessels. The decrease of this molecule only furthers the disease even more as arteries get smaller and more sickle cells are blocking the blood flow even easier.
The low red blood cells available make the bone-marrow, a tissue inside bones that create blood cells, to get bigger. This only causes a decrease in healthy bone tissue as the increase in bone marrow is not sufficient.
Simultaneously, obstruction is happening in the small arteries that transport blood to the inside of the bones. Resulting in the injury of the bones and joints and leading to pain, especially in long ones. Additionally, the patient becomes more susceptible to fractures, and growth diminishes, making them lose height and weight gain through life.
SCD patients also suffer from severe anemia chronically, as there is a reduced life span of red blood cells. Even though the hemoglobin levels are deficient, they usually don’t present much anemia symptoms because of its chronicity. Since they live all their lives with these low hemoglobin levels, the body gets used to them. Only when there are significant efforts like exercising or a really cold environment, they show anemic symptoms.
How painful is the sickle cell crisis?
One of the most characteristic symptoms of sickle cell crisis is pain, and for a good reason. Patients often suffer from severe pain when a crisis happens and, it can last from hours to various days. Pain frequently happens in one place, and there are a few common body sites such as:
- Hands and feet
- Chest and ribs
- Lower back
Another cause of pain that some patients have to deal with is something called priapism. This is an erection the patient does not desire and cannot control, making it long-lasting and painful.
When priapism is constant, it can lead to impotence even if a urologist applies proper treatment for the disease. Some people start to have priapism by the age of 12, and by the age of 20, almost 90% of SCD patients have had an episode.
Chronic pain is also prevalent in most patients, specifically in the lower extremities and joints. This pain is usually milder and can converge with sickle cell crises’ severe pain, making them challenging to differentiate. Sometimes chronic pain can be the only expression of pain but still deeply affects the patient’s day to day life.
Is sickle cell crisis an emergency?
Usually, sickle cell crisis pain forces the patient to go to an ER but isn’t necessarily life-threatening. There are other emergencies sickle cell disease can cause, putting the patient’s life in danger, such as:
- Aplastic crisis: When a healthy child gets parvovirus B-19 (Fifth disease), they get a fever, rash, weakness, and slight anemia. Since it infects the bone marrow, the tissue where the body produces red blood cells, the synthesis decreases, but because healthy red blood cells have a 120 days life span, it is enough to maintain their normal levels. In SCD patients who get the disease, it can be life-threatening because their red blood cells last approximately 20 days, instead of 120. Therefore, this means there is a period when the anemia becomes really prominent and puts the person in danger.
- Acute chest syndrome: Children present fever, cough, fast breathing, chest pain, and fluids inside the lungs. Most times is due to a lung infection, but SCD can also cause lung infarction. If doctors do not treat it on time, the disease can develop into something worse, leading to death.
- Pulmonary hypertension: Before the lungs oxygenate the blood. The blood has to get there through blood vessels that transport red blood cells without oxygen. That prompts more sickle cells in this area, causing obstruction, infarction, and hemolysis (premature death of red blood cells). As we also know, there is a decrease in nitric oxide because of the excessive release of hemoglobin. This causes constriction of blood vessels in the lungs, augmenting the blood pressure and leading to right heart failure.
- Splenic sequestration: This consists of severe anemia and an increase in the spleen’s size, which both can be fatal. The onset of splenic sequestration is fast, so it’s essential parents recognize it and head to a health center immediately.
How do you know if someone has a crisis?
Usually, people who have this disease can know from the moment of their birth by doing a Hemoglobin S screening. In countries like the US, it is a mandatory thing to do to every child born. In other countries where it is not mandatory, there’s usually a family member with SCD, and tests are done early. So by the time a person has their first sickle cell crisis, doctors have already given instructions to the parents.
In infants up to their six months of life, there is still something doctors call fetal hemoglobin. This protects most children until that age from getting a sickle cell crisis, as hemoglobin is coming from pregnancy.
When a hemoglobin screening takes place, it is essential to know that a higher percentage of hemoglobin will be fetal. Besides, this test can distinguish the different types of genes that produce and contribute to sickle cells from very early on. After the screening proves positive, hemoglobin electrophoresis must also be done to confirm the diagnosis and sub-type.
Finally, when the patient is having a crisis, it is enough to confirm it with the previous diagnosis and symptoms. More blood tests and imaging studies like CT scan can view any complications, like acute chest syndrome or splenic sequestration.
How do you treat a crisis?
When patients have a crisis, most of the time, they treat themselves in their homes following directions of their hematologist. Pain is usually taken care of with opioids, rest, and hydration; if it doesn’t work, they go to the ER. It is crucial to test for further complications in case that treatment is needed for them.
There are other options available in more severe cases such as:
- Bone marrow transplant: This is a permanent solution to the disease. Doctors transplant (or replace) the organ that produces sick red blood cells. It is not a first-line treatment as it has many risks and downsides that could do more harm than good if the patient doesn’t need the surgery.
- Blood transfusion: Doctors use transfusion specifically for aplastic crises, perioperative, acute chest syndrome, and in pregnant women. In other cases, the patient may need a red blood cell transfusion like infarction and organ failure.
- Hydroxyurea: It is a molecule that increases levels of fetal hemoglobin often used in adults. This drug diminishes the amount of vaso-occlusive crises a person has in a year and reduces most symptoms overall.
Why do sickle cell patients have a big stomach?
Sickle cell patients do not have a big stomach since the disease does not affect the stomach but other organs. Now, the spleen is directly next to the stomach, and as we now know, it can get a bigger size when splenic sequestration occurs.
This situation creates confusion in some people leading them to think the stomach got more prominent when the spleen actually gained some size. It happens in children most of the time and can be quite dangerous since the spleen is a fragile organ that can easily bleed after a trauma or injury.
Are you having symptoms of it?
This tool is a sickle cell anemia symptoms checker. It gathers the most important signs, symptoms, and risk factors for this condition. Therefore, it would help anyone who uses it to determine the likelihood of having this disease or its crisis. Please, feel loose to use the tool. It is free and would only take a few minutes to complete it.