Felty Syndrome - Symptoms, Diagnosis, Treatment and Complications

Introduction:

The immune system protects our body against foreign invaders like bacteria, viruses, fungi, and parasites. The reaction that happens within the body, which activates the immune cells to defend against the pathogen, is called the immune response.

Sometimes the immune system mistakenly attacks our own body cells. This condition is called an autoimmune disease. There are various autoimmune diseases and most of which occur with an unknown cause.

What Is Felty Syndrome?

Felty syndrome is an autoimmune disease that exhibits a group of symptoms without a definitive cause. The condition was first discovered in 1924 by an American physician, Augustus Roi Felty, at Johns Hopkins hospital, and later in 1932, Hanrahan and Miller described the condition and termed it Felty syndrome. The condition is otherwise known as Chauffard-Still-Felty-Syndrome since it was analogous to the disease described by Still and Chauffard.

The exact cause of Felty syndrome is unknown, but research shows strong evidence of genetic involvement. The condition is more prevalent among patients with rheumatoid arthritis and is more common in people in the age group of 50 to 70 years. The prevalence of Felty syndrome is estimated to be ten in 100000 patients with rheumatoid arthritis. Early occurrence of Felty syndrome is more in men, but women are three times more common to acquire this syndrome. Caucasians are affected more by this syndrome than the African-American population.

What Are the Signs and Symptoms of Felty Syndrome?

Felty syndrome is characterized by a triad of -

• Rheumatoid arthritis.

• Enlargement of the spleen.

• Low neutrophil count (a type of white blood cell important for immune response).

Patients often complain,

• Pain, stiffness, and swelling in the joints that mostly affect the upper and lower limbs.

• Pain and diffuse expansion in the abdomen (stomach region).

• Recurrent infection.

• Fever.

• Swollen lymph nodes.

• Leg ulcers.

• Skin pigmentation.

• Loss of appetite and weight loss.

• Weakness and fatigue.

Clinical findings are -

• Damage to the nerves, usually in the hands and legs.

• Inflammation in the layers of the eyeball.

• Anemia.

• Inflammation of the blood vessels.

• A decreased platelet count affects the clotting mechanism.

How Does Felty Syndrome Develop and Progress?

• Felty syndrome involves immune mechanisms which produce defective neutrophils resulting in decreased concentration of matured neutrophils in the blood. The loss and destruction of neutrophils increase the risk of developing chronic infections.

• In rheumatoid arthritis, the immune system attacks the body’s own tissues in the joints. The damage to the healthy tissues induces inflammation and fluid collection in the joints and causes swelling. Slowly there is a decrease in the joint space, and as the disease progresses, the bones in the joints get fused, and the mobility is completely occluded.

• The increased need for the production of white blood cells causes hyperactivity in the spleen and ultimately leads to spleen enlargement. It is more of an inflammatory condition.

How to Diagnose Felty Syndrome?

The following clinical evaluation and detailed investigations are used to diagnose Felty syndrome:

Medical History and Physical Examination: Physicians may evaluate the presence of rheumatoid arthritis and its severity, ulcers, lymph node enlargement, and nodules in the skin.

Blood Test: Complete blood count shows an absolute decrease in the neutrophil, which is a hallmark sign of Felty syndrome. Also, there is a low number of red blood cells and platelets in the bloodstream. Laboratory findings also exhibit the characteristic presence of certain antibodies and proteins associated with rheumatoid arthritis.

Imaging Techniques: X-rays are used to visualize severe joint destruction. Ultrasound and MRI (magnetic resonance imaging) scans can show an enlarged spleen and are helpful in measuring the dimensions.

The normal dimension of the spleen in adults is about 11 cm. Poulin et al. described splenomegaly (spleen enlargement) on the basis of the size of the spleen.

• Moderate: If the dimension is between 11 to 20 cm.

• Massive: If the dimensions are more than 20 cm.

Splenomegalycan also be defined by weight as follows,

• Normal: Averagely around 170 gms.

• Mild: If the spleen weighs between 400 to 500 gms.

• Moderate: If the spleen weighs between 500 to 1000 gms.

• Massive: If the spleen weighs more than 1000 gms.

Biopsy: Bone marrow aspiration and biopsy can show immature blood cells. Also, it is used to rule out other diseases associated with blood.

How to Treat Felty Syndrome?

The main aim of treatment for Felty syndrome is to control underlying arthritis and manage neutropenia (less neutrophil count) to prevent infections.

• Painkillers - NSAIDs (non-steroidal anti-inflammatory drugs), steroids, physiotherapy, occupational therapy, DMARD (disease-modifying antirheumatic drugs), and immunosuppressive drugs are suggested to improve arthritic conditions.

• Granulocyte Colony-Stimulating Factor (G-CSF) Therapy - Synthetic growth hormones to bring a significant increase in the absolute neutrophil count.

• Splenectomy (Removal of the Spleen) - It gave a marked improvement in neutrophil count. This surgical procedure was first suggested and tried by Hanrahan and Miller in 1932 and found a marked improvement in the clinical findings of Felty syndrome.

• Multiple Blood Transfusions - It may be required to combat fewer red blood cells and platelets.

• Monoclonal Antibody Therapy - This is a form of immunotherapy to attack the specific cells in the body.

• Gold Therapy - This was used in the olden days but discontinued owing to its extensive side effects.

What Are the Complications of Felty Syndrome?

• One of the most important complications of Felty syndrome is life-threatening recurrent infections, especially of the respiratory tract.

• Splenic rupture and internal bleeding.

• Increased risk of blood cancer (particularly non-Hodgkin’s lymphoma).

• Acute exacerbation of the underlying autoimmune disorder.

• Elevates the pressure in the veins of the liver and may result in bleeding along the lining of the gastrointestinal tract.

Conclusion:

Felty syndrome is a rare disease and requires an interdisciplinary team of doctors to effectively manage the condition. Early diagnosis and treatment can avoid potential complications since the consequence of treatment delay in Felty syndrome can be fatal. Patients with rheumatoid arthritis must be frequently screened for recurrent infections, internal bleeding, and abdominal pain, especially in the spleen region.

The treatment outcome for Felty syndrome depends on the severity of the symptoms and the patient's overall health. However, the collaborative approach of the physicians and patient compliance will give better treatment results.