Aplastic Crisis Definition
Aplastic Crisis, also known as Reticulocytopenia, is a condition characterized by an abnormal reduction of reticulocytes in one’s body. Reticulocytes are immature red blood cells (RBCs) with a network of granules or filaments. It occurs due to various factors which makes the body unable to produce red blood cells for a certain amount of time. This disorder can occur in patients suffering from blood disorders like Sickle Cell Disease and Spherocytosis. It can turn potentially life-threatening in some cases.
Aplastic Crisis Vs Hemolytic Anemia
Reticulocytopenia should not be mistaken for another condition named Hemolytic Anemia. It is a long-term condition that is present in Sickle Cell Anemia patients, while Reticulocytopenia is a short-term disorder occurring when the RBC production stops temporarily. Due to this reason, it is also referred to as transient Aplastic Crisis.
Aplastic Crisis Causes
There are numerous types of infections that prevent the bone marrow from producing the required amount of red blood cells. Most of these infections affect children of school-going age, but can also occur in adults. Infection caused by the parvovirus B19 most commonly leads to this disorder as it shuts down the production of RBC in a child for around 10 days.
Aplastic Crisis Signs and Symptoms
Low RBC count gives rise to many mild to severe problems in patients, such as:
Picture 1 - Aplastic Crisis
- Pale lips, gums and nail beds
- Being sleepy and tired all the time
- Fever with temperature above 101°F
- Increased heart rate
- Shortness of breath
- Being easily irritated
- Eye pain and photophobia
Aplastic Crisis Diagnosis
In most cases, the diagnosis of Reticulocytopenia caused by parvovirus B19 infection is presumptive. A doctor supposes the presence of the condition depending on a reducing hemoglobin value accompanied by an abnormally low reticulocyte-count in a patient suffering from Hemolytic Anemia. Certain DNA examinations can be used for confirming the diagnosis by PCR (polymerized chain reaction) due to the robust type of viremia present in the patient. A rising IgM (immunoglobulin M) antibody to parvovirus B19 is another way to confirm this diagnosis.
The following diagnostic tests can be used for detecting this condition:
- Physical exam
- Complete Blood Count (CBC)
- Parvovirus B19 test
- Blood culture for detecting any germs in the blood
- Cross-matching blood (in patients requiring blood transfusion)
- Chest X-ray
Aplastic Crisis Differential Diagnosis
This disorder generally occurs due to B19 infection, although there are other less frequent factors that can lead to Reticulocytopenia. These include certain bacterial infections (like pneumococcal septicaemia) and drugs that suppress the functioning of the bone marrow such as chloramphenicol. It is important for a diagnostician to confirm the exact cause behind the blood disorder.
Rubella is another condition to rule out during the diagnosis of parvovirus B19 infection.
Aplastic Crisis Treatment and Management
The condition generally calls only for certain supportive measures. In most cases, patients need blood transfusions which help to increase the RBC count until their bodies are capable of producing the required amount of red blood cells again. Most patients do not require more than one blood transfusion for fighting the bone marrow suppression responsible for the disease. Parvovirus B19 does not suppress the BFU-E. Due to this reason, the bone marrow responds very quickly to the treatment once the virus causing the infection is destroyed.
Other possible treatment options include:
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- IV fluids
- Oxygen therapy
- Pain-relieving medications (analgesics)
In some very rare cases, the immunoglobulin treatment may be necessary. This procedure is very effective for reversing this type of aplasia. Immunoglobulin concentrate is most commonly used for this treatment and is administered as 0.4 g/kg/day for five days.
Individuals with Reticulocytopenia require regular checkups to determine whether the blood count is normal even after achieving complete recovery.
Aplastic Crisis Prognosis
The prognosis is positive in most patients as it is a temporary condition. Timely treatment allows affected children to attain full recovery within a reasonably short time. Adults with the disorder can also be treated successfully with appropriate treatment options.
Aplastic Crisis Prevention
There are no known ways to prevent the occurrence of this condition as many of its possible trigger factors are not clearly known. It is advisable to stay away from people with parvovirus B19 infection as it is contagious. Children suffering from this infection should never go near pregnant women, individuals with weak immune systems and other children with conditions like Sickle Cell Disorder. This helps to prevent further transmission of the virus. However, this virus is generally not harmful for healthy individuals.
Aplastic Crisis is a transient blood disease caused by viral infection. Children with Sickle Cell Anemia often develop the disease and require prompt medical attention. Siblings suffering from Sickle Cell disorders should be monitored regularly for any signs of the contagious infection resulting in Reticulocytopenia.