Felty’s Syndrome, Insights and Updates

Abstract

Felty’s syndrome (FS) is characterized by the triad of seropositive rheumatoid arthritis (RA) with destructive joint involvement, splenomegaly and neutropenia. Current data shows that 1-3 % of RA patients are complicated with FS with an estimated prevalence of 10 per 100,000 populations. The complete triad is not an absolute requirement, but persistent neutropenia with an absolute neutrophil count (ANC) generally less than 1500/mm3 is necessary for establishing the diagnosis. Felty’s syndrome may be asymptomatic but serious local or systemic infections may be the first clue to the diagnosis. FS is easily overlooked by parallel diagnoses of Sjӧgren syndrome or systemic lupus erythematosus or lymphohematopoietic malignancies. The role of genetic (HLA DR4) is more prominent in FS in comparison to classic rheumatoid arthritis. There is large body of evidence that in FS patients, both cellular and humoral immune systems participate in neutrophil activation, and apoptosis and its adherence to endothelial cells in the spleen. It has been demonstrated that proinflammatory cytokines may have inhibitory effects on bone marrow granulopoiesis. Binding of IgGs to neutrophil extracellular chromatin traps (NET) leading to neutrophil death plays a crucial role in its pathophysiology. In turn, "Netting" neutrophils may activate auto-reactive B cells leading to further antibody and immune complex formation. In this review we discuss on basic pathophysiology, epidemiology, genetics, clinical, laboratory and treatment updates of Felty’s syndrome.

A Case Report of Chikungunya Fever, Rheumatoid Arthritis, and Felty’s Syndrome

“…The illness was consistent with American College of Rheumatology (ACR)/ European League Against Rheumatism (EULAR) 2010 classification criteria for rheumatoid arthritis [5]. The diagnosis of Felty's syndrome was also established, based on the triad of rheumatoid arthritis, neutropenia, and splenomegaly [6].…”

Phenotypic variability in a child with Felty’s syndrome: a case report

“…FS is an uncommon but severe extra-articular manifestation of rheumatoid arthritis, including hepatopathy, lymphadenopathy, vasculitis, leg ulcers, abnormal skin pigmentation and a high frequency of rheumatoid nodules [2,9]. There is no specific diagnostic criterion for FS.…”

“…There is no specific diagnostic criterion for FS. FS is a clinical diagnosis in patients with RA or JIA with unexplained neutropenia and splenomegaly [2,10].…”

“…The level of hemoglobin was below the normal range only in patient 5. Adult FS is three times more common in females [2], but most children with FS have been females so far. Adults diagnosed with FS are usually 50-70 years of age and have had RA for more than 10 years [9,13], while the average age at onset of JIA is only 9.2 years (range from 4.0-15.0), and the duration of JIA until FS is 6.2 years (range from 4.0-15.0).…”

“…Typically, FS tends to affect patients with long-standing erosive RA. It usually develops after a > 10year course of RA [2], with increased risk in patients with a positive family history of RA. The complete triad is not an absolute requirement, but persistent neutropenia with an absolute neutrophil count (ANC) less than 1500-2000/mm 3 is generally regarded as necessary for establishing the diagnosis in adult [3].…”