Felty syndrome is a rare complication of rheumatoid arthritis. People with the condition have an enlarged spleen, decreased white blood cell count, and recurrent infections.
Rheumatoid arthritis (RA) is an autoimmune and inflammatory disease that mainly attacks joints.
However, RA may also have other symptoms that affect other body parts beyond the joints. These are often severe complications of long-term inflammation relating to RA.
Felty syndrome is an uncommon complication of RA.
In this article, we cover Felty syndrome, including its causes, symptoms, treatment, and more.
RA has two types: seropositive and seronegative. Seronegative RA generally has a
People with seropositive RA have
Felty syndrome is a rare complication of seropositive RA. It involves the
- chronic rheumatoid arthritis
- enlarged spleen, which doctors call splenomegaly
- neutropenia, or a low neutrophil count — neutrophils are a type of white blood cell
While the three symptoms typically characterize the condition, all three do not need to be present for a Felty syndrome diagnosis. However, neutropenia is a key feature of the condition and should be present.
Felty syndrome occurs in
The underlying cause of Felty syndrome is unclear. However, multiple factors, such as autoimmunity and genetics, likely play a role.
There is a
Experts also believe that Felty syndrome is an autoimmune disorder that occurs due to an allergy, blood disorder, or unknown immune disturbance.
Felty syndrome affects females three times more than males. The condition also affects more Caucasians than African Americans.
The syndrome tends to occur in people with a long-term and aggressive type of RA for
Felty syndrome manifests in people with severe RA, which is
Symptoms typically develop around 16 years after the initial onset of RA.
People with the condition do not usually experience symptoms other than recurrent infections due to low immunity. However, some may develop severe, life threatening infections.
Other symptoms of Felty syndrome
- rheumatoid nodules
- liver enlargement, which doctors call hepatomegaly
- enlarged or swollen lymph nodes, which doctors call lymphadenopathy
- leg ulcers
- Sjögren’s disease
- pulmonary fibrosis
- peripheral neuropathy
- certain cancers, such as Hodgkin lymphoma
- portal hypertension, or heightened pressure in the portal venous system
Doctors diagnose Felty syndrome by taking a detailed medical history and performing a thorough clinical evaluation.
Neutropenia is a hallmark feature of Felty syndrome. If a doctor suspects Felty syndrome, they will order a complete blood count.
An absolute neutrophil count of under 2,000 per microliter is necessary to diagnose someone with Felty syndrome.
Other lab tests that can help diagnose the condition
- a rheumatoid factor test
- cyclic citrullinated peptide antibody test
- antinuclear antibodies
- anti-histone antibodies
Imaging can also help detect the presence and extent of joint damage and spleen enlargement.
The doctor may also request a bone marrow biopsy to rule out large granular lymphocyte leukemia and non-Hodgkin lymphoma.
Treatments will aim to control a person’s underlying RA and treat neutropenia to reduce their risk of infections.
Long-term management of the underlying RA involves prescribing disease-modifying antirheumatic medications (DMARDs). These include:
If a person does not respond to DMARDs, the doctor may prescribe rituximab.
Doctors may also prescribe granulocyte colony-stimulating factor (G-CSF), which encourages the bone marrow to produce more white blood cells. Healthcare professionals recommend this treatment in people with a neutrophil count of less than
Learn more about DMARDs and biologics.
A doctor will start a person on broad-spectrum antibiotics if they have an active infection.
Additionally, adequate oral hygiene and staying updated on vaccinations can help
People with the condition who do not improve with conventional treatment may qualify for a splenectomy, an operation to remove the spleen.
Before the introduction of DMARDs, the 5-year mortality rate for Felty syndrome was
Treating the underlying RA should improve Felty syndrome in most people. However, without treatment, infections may occur, and the RA may worsen.
Advanced treatment options for RA gradually decrease the severity and presence of extra-articular manifestations, which are complications or symptoms that occur outside of affected joints. The use of G-CSF can also reduce the need for splenectomy.
Felty syndrome is a rare disease that occurs as a complication of RA. Chronic RA, splenomegaly, and neutropenia characterize the disease. However, a person may have Felty syndrome without having all these three conditions.
A low white blood cell count puts a person at risk of recurrent infections. Generally, Felty syndrome responds well to DMARDs and other conventional RA treatments. If symptoms do not improve, an individual may be a candidate for spleen removal.