Pancytopenia is the medical term used to describe the condition when all three major formed elements of blood (red blood cells, white blood cells, and platelets) are low in number.
When red blood cells, white blood cells, or platelets are low, we call that anemia, leukopenia, or thrombocytopenia, respectively. But that’s more than a mouthful, so thankfully we can just say pancytopenia. When you break the word down, it explains itself beautifully:
penia: poverty, lack
Pancytopenia is not a disease. Rather, it is a sign of disease. All three cell lines are decreased, either because of bone marrow problems or destruction of the cells outside of the bone marrow.
Clinical signs of pancytopenia include pallor and bleeding disorders, mostly due to low numbers of red blood cells and platelets. In general, clinical signs of the primary disease that is causing pancytopenia are more evident and will vary significantly depending on the disease process.
Below are some of the more common reasons for pancytopenia in dogs and cats.
Exposure to bone marrow suppressing drugs.
Estrogen. Pets are either purposely given the medication or accidentally exposed through their owner’s topical therapy. Rarely, male pets can have tumors that produce excess estrogen.
Some veterinary antibiotics, antifungals, and dewormers, as well as methimazole, which is used to treat feline hyperthryoidism, can cause bone marrow suppression in rare individuals.
Chemotherapy drugs can (and often do) suppress the bone marrow.
Parvovirus, feline leukemia virus (Felv), feline immunodificiency virus (FIV), and Ehrlichiosis (either chronic or acute).
Bacterial infections leading to septicemia and endotoxemia are also to blame for some cases of pancytopenia.
Malignant histiocytosis, lymphoma, and carcinomas are all capable of suppressing the production of blood cells.
Pancytopenia can also be caused by factors outside of the bone marrow, such as direct destruction of the blood cells themselves. This most commonly occurs in patients with immune-mediated hemolytic anemia (IMHA) and immune-mediated thrombocytopenia (IMT).
The prognosis for patients with pancytopenia depends largely on the underlying condition, therefore it is important to establish the reason for pancytopenia. Tests to rule out infectious diseases and ruling out drug induced pancytopenia are important parts of the diagnostic work-up. Bone marrow aspirates or biopsies may also be required, and will be covered by your pet insurance policy.
There is no specific treatment for pancytopenia, as treating the underlying cause will often address the blood cell deficiencies. Severe cases may require transfusions of one or more component of blood, however.
If pancytopenia is present on your pet’s blood work, you can be sure that your veterinarian will be looking for the cause. Recovery time will vary, but the sooner the underlying cause is found, the better!