A granulocyte is a type of white blood cell. Agranulocytosis is when the body is not producing enough granulocytes.
The white blood cells are a crucial part of the immune system, so a person with this condition is at risk of developing a severe or even life-threatening infection.
Granulocytes are also known as neutrophils or white blood cells. They are an important part of the body’s immune system because they contain enzymes that kill bacteria and other foreign pathogens.
Without these white blood cells, the body is not able to fight off or remove potentially dangerous pathogens or foreign materials.
The symptoms of agranulocytosis are usually similar to those of an underlying infection and can include:
If the infection is left untreated, it can spread quickly throughout the body and even into the blood, causing a condition known as sepsis, which can be life-threatening without quick treatment.
Symptoms of sepsis also include rapid heartbeat, fast breathing, and a change in mental state.
Causes and risk factors
HIV, medication for an overactive thyroid gland, and chemotherapy may cause agranulocytosis.
There are two types of agranulocytosis: acquired or congenital.
Acquired agranulocytosis means that a person develops the condition, whereas congenital agranulocytosis means that a person is born with the condition.
Certain conditions or medications that affect the immune system can cause acquired agranulocytosis. These include:
- bone marrow transplant
- autoimmune disorder
- bone marrow disease or leukemia
- infections such as HIV
- taking certain medications, such as Clozapine (an antipsychotic)
- taking medications for an overactive thyroid gland
People with these conditions are at higher risk for developing agranulocytosis and should be monitored periodically for this condition.
A person with agranulocytosis or any of these risk factors should always report any signs of infection to their doctor to ensure prompt treatment and prevent a more serious infection developing.
Diagnosing agranulocytosis is done through a simple blood test to check the number of white blood cells in the blood.
Typically, doctors diagnose agranulocytosis when the number of neutrophils (granulocytes), known as the absolute neutrophil count (ANC), is less than 100 per microliter (mcL) of blood.
A normal ANC is at least 1,500 neutrophils per mcL of blood.
If someone has a neutrophil count between 100 and 1,500 per microliter of blood, it is called granulocytopenia or neutropenia. It means that there are too few neutrophils in the blood, which can also raise the risk of infection.
The doctor will also perform a physical exam and take a medical history. If the ANC level is abnormal, the doctor may recommend further testing, such as a bone marrow biopsy or genetic blood tests to determine what is causing the agranulocytosis.
Treatment aims to manage the cause of agranulocytosis and restore the white blood cell count back to normal. Possible treatments include:
- Stopping a medication: If the doctor believes that a medication may be responsible, they may recommend that the person stops taking it and prescribe an alternative drug. The doctor will monitor blood tests to see if the ANC improves, which may take up to 2 weeks. If stopping the drug is not an option, then the doctor will closely monitor blood tests and watch for early signs of infection.
- Antibiotics: Antibiotics can prevent new infections and treat existing infections. Also, doctors may prescribe anti-viral or anti-fungal medications to treat viral or fungal infections.
- Granulocyte colony-stimulating factor: Granulocyte colony-stimulating factor, or G-CSF, is an injection that stimulates the bone marrow to produce more white blood cells. This medication can be effective in some people with cancer who are undergoing chemotherapy. Three forms of G-CSF are currently available: filgrastim (Neupogen), pegfilgrastim (Neulasta) and lenograstim (Granocyte).
- Immune suppressing medications: This type of medicine is effective against agranulocytosis that has been caused by an autoimmune disorder. Immune suppressing medications, such as some steroids, can be used to reduce the immune attack on white blood cells and the bone marrow.
- Granulocyte infusions: In rare cases, a person may undergo a transfusion of granulocytes, which is similar to a blood transfusion. The donor cells must be taken from a match, ideally from a close relative. The donor is given a steroid and G-CSF to boost their granulocyte production. Once the blood has been removed, the granulocytes are separated out for transfusion into the recipient.
- Bone marrow transplant: When medication and other measures are not working, the doctor may consider a bone marrow transplant. In this treatment, marrow from a healthy donor replaces the bone marrow in the person with agranulocytosis. The new bone marrow means that the body can produce healthy white blood cells. Unfortunately, it can sometimes be difficult to find a matching donor.
There is no way to prevent agranulocytosis. However, it is crucial for people with this condition to prevent infections.
Washing hands regularly and with soap and water, as well as maintaining good personal hygiene, can help to prevent infections.
In addition to staying away from someone who is sick, people with agranulocytosis should:
- avoid crowds
- avoid cut flowers
- not eat fruits and vegetables that cannot be peeled or thoroughly washed
- avoid working in the soil or with animals
- not eat undercooked or raw foods
- maintain good personal hygiene
- regularly wash hands with soap and water
- store and prepare food properly
Agranulocytosis can be a dangerous condition because it can put someone at risk for a serious infection. If a person does not seek prompt treatment, they may develop sepsis, which can quickly become life-threatening.
In most cases, when the cause of the agranulocytosis is identified and treated, a person’s white blood cell count and their risk of developing an infection will return to normal.