Levels of chemerin and interleukin 8 in the synovial fluid of patients with inflammatory arthritides and osteoarthritis

OBJECTIVES

Chemerin and interleukin (IL)-8 are pro-inflammatory mediators whose role in joint inflammation and cartilage degradation has been demonstrated in in-vitro findings. Studies on their presence in synovial fluid (SF) samples may offer further information on their pathogenic role. The aim of this study was to investigate SF chemerin and IL-8 levels in patients with different joint diseases.

METHODS

37 patients were enrolled: 18 with rheumatoid arthritis (RA), 8 with psoriatic arthritis (PsA) and 11 with osteoarthritis (OA). 41 SF samples were obtained by arthrocentesis in case of knee synovitis. Serum samples were obtained from 13 patients (4 with RA, 6 with PsA and 3 with OA) at the time of arthrocentesis. Chemerin, IL-8, TNF-α and IL-6 levels were measured using commercially available ELISA kits. Immunohistochemical analysis of synovial RA specimens was also performed.

RESULTS

No difference in chemerin SF levels emerged between patients with immune-mediated inflammatory arthritides and those with OA (p=0.0656), while subjects with inflammatory arthritis displayed significantly higher levels of SF IL-8 compared to OA (p=0.0020). No significant difference emerged across the three conditions in the serum levels of both chemerin and IL-8. IL-8 strongly correlated with inflammatory markers as ESR, CRP, IL-6 and TNF-α.

CONCLUSIONS

We observed similar chemerin SF and serum levels in the three conditions. Although flawed by some limitations, our findings support the emerging concept of OA as an inflammatory disorder. However the increased IL-8 levels we described in patients with inflammatory arthritis suggest a selective involvement of this pro-inflammatory and angiogenic cytokine in these conditions.

[Long-term evaluation of infliximab in the treatment of persistently active juvenile idiopathic arthritis refractory to conventional therapy]

OBJECTIVES

To evaluate, in long-term open label prospective study, infliximab as therapeutic choice for Juvenile Idiopathic Arthritis (JIA) non responsive to conventional therapy.

METHODS

We enrolled to treat with infliximab 78 JIA patients (66 females, 12 males): the mean age was 20.7+/-7.1 years (median 20.9, range 5.4-34.9); mean JIA duration was 13.6+/-7.6 years (median 13.5, range 0.4-31.4). Infliximab, at dose of 3-10 mg/kg/infusion added to weekly subcutaneous Methotrexate or other previous DMARDs, was administered by intravenous infusions at weeks 0, 2, 6 and every 8 weeks thereafter. Chest X-ray, Mantoux's test, electrocardiogram were performed at baseline; laboratory tests and clinical evaluation were performed at each infusion. Response was evaluated according to ACR improvement criteria.

RESULTS

Mean treatment period was 21.6 months+/-18.8 (median 14.7, range 1.4-72.4). Just after first infusion most of patients reported significant improvement in pain, fatigue, morning stiffness. Infliximab is still successfully administered to 23 patients (29.5%); 55 (70.5%) patients suspended because of: inefficacy (7), infusion reactions (17), adverse events (9), disease flare-up after a period of effectiveness on synovitis, pain, and morning stiffness (19), remission (2), lack of compliance to treatment (1). Infusion reactions, like dyspnea, flushing, chills, headache, hypotension, anxiety, throat oedema, were observed in 29 patients (34.5%). Anti-DNA antibodies were present in 7 patients (none developed Systemic Lupus Erythematous).

CONCLUSIONS

Infliximab showed impressive effectiveness treating refractory JIA, although most of patients had to discontinue treatment because of disease flare-up or adverse events. Infliximab may represent a good therapeutic choice in patients non-responders to Methotrexate.

[Simultaneous ultrasonography and arthroscopy for the study of the joint environment: indications and limits]

Arthroscopy is a mini-invasive technique that allows the direct observation of the joint cavity and the execution of diagnostic and therapeutic procedures; arthroscopy needs a very long learning-time curve as well as dedicated spaces and instruments. Ultrasonography is an imaging technique that enables to perform an immediate extension of the standard physical examination. The opportunity to visualize soft tissues, to obtain multiplanar and dynamic images in real time makes this practice easy repeatable at low costs. Ultrasonography allows to detect a variety of changes during inflammatory processes. The wide experience in arthroscopy of rheumatic patients acquired through the years by our team at the G. Pini Institute led us to study in vivo, during arthroscopy, the correspondence between arthroscopic and ultrasonographic images. Up to now three knee arthroscopies have been conducted with the double equipment (ultrasonographic and arthroscopic devices) in operating room. In our experience, the combination of the two methods in operating room may improve the validation of ultrasonography with arthroscopy as gold standard, helps to train the ultrasonographer to give immediate answers in order to clear the doubts aroused by ultrasonographic images; it also allows the arthroscopist to visualize the deeper layers of the synovial membrane making double guided targeted biopsies possible. Limits are the complexity of the procedure (instruments, operators, spaces, training of the doctors), the loose of power-doppler signal with the blood tourniquet and the always difficult evaluation of cartilage.