Felty syndrome is a symptom complex that includes the main triad of signs: rheumatoid arthritis, splenomegaly and leukopenia. In addition to these symptoms, the course of Felty syndrome is accompanied by fever, muscular atrophy, pigmentation and ulcers on the skin of the shins, polyserositis, polyneuropathy, episcleritis, lymphadenopathy, hepatomegaly, a tendency to infectious diseases. In the diagnosis, crucial importance is attached to the presence of a history of rheumatoid arthritis and laboratory parameters (high titers of RF, leukopenia, neutropenia, thrombocytopenia, etc.). The therapeutic algorithm includes the appointment of corticosteroids (lithium or gold salts, D-penicillamine), plasmapheresis; splenectomy.
ICD 10
M05.0 Felty syndrome
Meaning
Felty syndrome is an independent variant of the articular-visceral form of rheumatoid arthritis, combining polyarthritis, leukopenia, enlargement of the spleen (splenomegaly), skin pigmentation and other clinical and laboratory signs. Syndrome develops in about 1-5% of patients with rheumatoid arthritis. The disease was differentiated into an independent nosology in 1929. Women predominate among the sick (sex ratio 3:1) over the age of 40-50 years. In rheumatology, syndrome is extremely rare, so there are many gaps in the etiology, pathogenesis, diagnostic and therapeutic tactics of this pathology.
The etiology of pathology has been studied even less than rheumatoid arthritis. It is known that the syndrome is an HLA-DRw4 associated disease. The mechanism of neutropenia development is explained by the fact that circulating immune complexes formed in the body of patients with Felty syndrome disrupt the functions of neutrophils and activate their phagocytosis, mainly in the spleen. This is confirmed by the detection of deposits in the cytoplasm of neutrophils containing immunoglobulins (IgG, IgM) and complement, as well as specific antibodies to leukocytes (including antigranulocyte antibodies). In addition, humoral and cellular immunity factors that inhibit leukopoiesis in the bone marrow are assumed to be involved in the occurrence of neutropenia.
Symptoms
Felty syndrome occurs in patients with seropositive rheumatoid arthritis (i.e., with a positive rheumatoid factor) on average 10 years after joint damage. Articular symptoms are characterized by the development of polyarthritis with the predominant involvement of small joints of the hands and feet. The presence of other manifestations of rheumatoid arthritis is also characteristic: subcutaneous nodules, fever, polyneuropathy, amyotrophy, generalized lymphadenitis. In addition, systemic visceral lesions in Felty syndrome include myocarditis, polyserositis, episcleritis, hepatomegaly. The spleen is dense to the touch, painless; its size usually increases significantly, and the weight is on average 4 times higher than normal.
In half of the cases, Sjogren’s syndrome develops; pigmentation and ulcers may appear on the skin of the shins. Due to leukopenia and suppression of immunity, patients with Felty syndrome are prone to infectious diseases: recurrent acute respiratory infections, pneumonia, recurrent pyoderma, etc. The course of Felty syndrome can be complicated by rupture of the spleen, portal hypertension, gastrointestinal bleeding, amyloidosis.
Diagnostics
The basis for the clinical diagnosis is a combination of rheumatoid polyarthritis and splenomegaly. The blood test is characterized by leukopenia, neutropenia, thrombocytopenia, anemia. Immunological examination of blood in Felty syndrome reveals high RF titers, the presence of antinuclear antibodies (especially antigranulocyte antibodies), CEC, hypergammaglobulinemia (increased IgG and IgM). According to the myelogram, myeloid hyperplasia of the bone marrow with a shift towards immature cellular elements is detected. The data of instrumental studies (ultrasound of joints, radiography, MRI and CT) are not informative enough. Felty syndrome should be differentiated with lymphomas, sarcoidosis, cirrhosis of the liver, hepatolienal syndrome.
Treatment
The search for ways to effectively treat Felty syndrome continues. Currently, lithium preparations are used to stimulate granulocytopoiesis, but their use can cause side effects: tremor, tubulo-interstitial nephritis, hypothyroidism. In order to reduce the risk of intercurrent infections, it is advisable to introduce a granulocytostimulating factor. Within the framework of therapy aimed at blocking the formation of antigranulocytic AT, the appointment of glucocorticoids, basic drugs (D-penicillamine, gold salts, methotrexate), plasmapheresis is indicated. With severe leukopenia and splenomegaly, splenectomy is indicated, but in a quarter of patients, even after removal of the spleen, neutropenia recurs. Prevention of Felty syndrome has not been developed; the prognosis is very serious. Felty syndrome increases the risk of non-Hodgkin’s lymphomas.