Protracted arthritis in a Japanese patient with familial Mediterranean fever.

The most common arthritic involvement in familial Mediterranean fever (FMF) is acute self- limiting monoarthritis which typically lasts for 72 h. Hip joint involvement is uncommon in FMF and can result either from a process specific to this disease or from a coexisting inflammatory joint disease. We describe a 37-year-old woman with FMF and right osteoarthritis secondary to congenital hip dislocation. Periodic fever with right coxalgia lasting for 6 months was treated using colchicine. Genetic analysis revealed homozygous mutation in the MEFV gene (L110P-E148Q/L110P-E148Q), confirming the FMF diagnosis. Although the clinical presentation and course of FMF arthritis are diverse, delineating these clinical patterns may help with early recognition and treatment to prevent destructive arthritis in FMF. Clinicians should consider the possibility of FMF development in unusual monoarthritis patients with recurrent febrile attacks.

Multicentric Castleman disease mimicking IgG4-related disease: A case report.

A 50-year-old woman was referred to our hospital for shoulder joint stiffness. She had a history of polyclonal hypergammaglobulinemia and an elevated C-reactive protein level. Her laboratory data revealed an elevated serum immunoglobulin G4 (IgG4) level, hypergammaglobulinemia, and rheumatoid factor positivity in the absence of anticyclic citrullinated peptide antibody. [18F]-Fluorodeoxyglucose positron emission tomography showed significant [18F]-fluorodeoxyglucose uptake in multiple lymph nodes (axillary, hilar, para-aortic, and inguinal). Biopsy of the inguinal lymph node showed expansion of the interfollicular areas by heavily infiltrating plasma cells, consistent with multicentric Castleman disease (MCD). Immunohistochemical analysis revealed a 37.3% IgG4-positive:IgG-positive plasma cell ratio, indicating overlapping IgG4-related disease. However, serological cytokine analysis revealed elevated levels of interleukin-6 (9.3 pg/ml) and vascular endothelial growth factor (VEGF) (1210 pg/ml), which are compatible with MCD. Corticosteroid treatment resolved the serological and imaging abnormalities. IgG4-related disease can mimic MCD, and it is crucial to distinguish between these two diseases. Serum interleukin-6 and VEGF levels may help to discriminate MCD from IgG4-related disease.

Myelodysplastic syndrome precedes the onset of remitting seronegative symmetrical synovitis with pitting edema (RS3PE) syndrome.

Remitting seronegative symmetrical synovitis with pitting edema (RS3PE) syndrome is characterized by symmetrical synovitis predominantly involving the wrists, and is associated with marked pitting edema of the dorsum of the hands. Although the etiology of RS3PE syndrome is still unknown, several putative associations with malignancies and hematological disorders have been reported. Myelodysplastic syndrome (MDS) is characterized by infective hematopoiesis with possible transformation to leukemia; however, an association between RS3PE syndrome and MDS has been rarely reported. Here, we describe a 67-year-old man with MDS with refractory anemia who developed RS3PE syndrome 3 months after the diagnosis of MDS. The patient presented with polyarthritis with pitting edema at the dorsum of the hands, the elevated serum levels of C-reactive protein and a proinflammatory cytokine, interleukin-6, and the elevated plasma levels of vascular endothelial growth factor (VEGF). VEGF has been shown to be involved in the pathogenesis of RS3PE syndrome. Treatment with low doses of corticosteroids resulted in the regression of polyarthritis and pitting edema of the dorsum of the hands, as well as a reduction in the elevated levels of plasma VEGF. Partial resolution of refractory anemia was also observed with steroid therapy. In summary, RS3PE syndrome developed shortly after MDS was identified in this patient. The sequence of clinical events suggests that MDS-mediated immunological abnormalities including inflammatory cytokine induction may be responsible for the association between MDS and RS3PE syndrome. Patients with RS3PE syndrome should be screened for hematological disorders that promote proinflammatory mediators.