Rheumatoid Arthritis: Calabri GB

Simonini G, Azzari C, Gelli AM, Giani T, Calabri GB, Leoncini G, Del Rosso A, Generini S, Cimaz R, Cerinic MM, Falcini F. · Rheumatology Unit, Department of Pediatrics, University of Florence, Via Pico della Mirandola 24, 50132 Florence, Italy. · Rheumatol Int. · Pubmed #14997340 No free full text.

Abstract: OBJECTIVE: Neprilysin (neutral endopeptidase, 3:4:24:11, CD10) (NEP) is a Zn metallopeptidase linked to controlling inflammation through the degradation of neuropeptides involved in neurogenic inflammation of chronic rheumatic diseases. The aim of our study was to evaluate circulating activity and cellular expression of NEP in the plasma of 58 children with juvenile idiopathic arthritis (JIA) and 52 controls. In 20 subjects requiring local steroid injection, NEP was measured in synovial fluid. METHODS: Plasma and synovial NEP were evaluated using a fluorimetric technique. Neprilysin, expressed as the antigen CD10, was determined on circulating and synovial fluid cells as mean fluorescence intensity (MFI) and as percentage of positive cells by two-color immunofluorescence. RESULTS: Circulating NEP levels were lower in JIA patients than in controls (42.0+/-16.6 vs 76.5+/-24 pmol/ml per min, P<0.001), while synovial fluid NEP values were higher than circulating levels (241.4+/-86.2 vs 40+/-15.3 pmol/ml per min, P<0.001). In monocytes, the percentage of CD10-positive circulating cells and the MFI in JIA were lower than in controls (11.6+/-5.2% vs 41.4+/-13%, P<0.001 and 18.1+/-7.5 vs 31.2+/-5.4, P<0.05, respectively). On synovial monocytes, the percentage of CD10-positive cells and the MFI were higher than on circulating monocytes (35.2+/-14.6% vs 9.1+/-2.4%, P<0.001 and 66.4+/-5.4 vs 22.8+/-14.7, P<0.001, respectively). CONCLUSIONS: The downregulation of CD10 expression in monocytes and the reduction in NEP activity may be linked to the enzyme's role in the control of peptides involved in the inflammation. The increased levels of NEP, MFI, and CD10-positive monocytes in synovial fluid, even though in plasma, might reflect a reactive effort to control synovial proliferation.

Falcini F, Ferrari R, Simonini G, Calabri GB, Pazzaglia A, Lionetti P. · Rheumatology Unit, University of Florence, Italy. · Clin Exp Rheumatol. · Pubmed #10464568 No free full text.

Abstract: A case of occult coeliac disease (CD) presenting with recurrent monoarthritis in a boy aged 11 years is reported. The case is unique due to the association of occult untreated CD and arthritis in childhood. Peripheral or axial arthritis as a first manifestation of occult CD has been described in adult patients, with an interval between the arthritis and CD of up to 15 years. In our case the interval between the appearance of arthritis and the diagnosis of CD was 2 years. The boy was asymptomatic for bowel disease and his nutritional status was normal. The diagnosis of CD was established using anti-gliadin (AGA) and anti-endomysium (EMA) antibody tests and was confirmed by small bowel biopsy. The introduction of a gluten-free diet resulted in the persistent remission of arthritis. As the treatment of CD-associated arthritis is based on dietary therapy, physicians should be alert to the possibility of occult CD in any child with arthritis of unclear origin.