Israel Medical Association Journal

Background: Methotrexate is the most frequently administered first-line treatment for rheumatoid arthritis (RA). The disease-modifying effects of methotrexate are mainly associated with enhanced release of free adenosine. The downstream anti-inflammatory effects of adenosine are mediated via its binding to adenosine receptor 2A (ADORA2A) and 3 (ADORA3). Many clinically important single nucleotide polymorphisms (SNPs) were reported in ADORA2A and ADORA3 genes.

Objectives: To investigate whether tagging ADORA2A and ADORA3 polymorphisms influences methotrexate treatment in RA.

Methods: In total, 212 RA patients treated with methotrexate were genotyped for tagging ADORA2A (rs2298383, rs8141793, rs2236624, rs5751876, rs35320474, and rs17004921) and ADORA3 SNPs (rs2298191, rs1544223, rs78594984, rs35511654, rs2229155, rs3393, and rs3394).

Results: RA patients who carried ADORA3 rs35511654 G allele showed a tendency toward better response to methotrexate treatment (P = 0.054). Carriers of ADORA2A polymorphic allele rs2298383 (P = 0.011), rs2236624 (P = 0.027), rs5751876 (P = 0.018), and rs35320474 (P = 0.026) were less likely to experience methotrexate induced adverse events. All associations remained significant after adjustment for clinical factors. The effects of these polymorphisms were also significant in haplotype analyses.

Conclusions: Polymorphisms in the ADORA2A gene may influence methotrexate treatment response and may be considered as a potential biomarker for methotrexate treatment in rheumatoid arthritis.

Background: Atopic dermatitis or atopic eczema is an itchy inflammatory skin condition with a predilection of the skin flexures. Most cases start in children although some have been reported in adults. Patients with moderate to severe disease refractory to topical corticosteroid or calcineurin inhibitors may require second-line treatment such as phototherapy or systemic immunosuppressants. Methotrexate therapy has been suggested to be a useful immunosuppressant in adult atopic dermatitis.

Objectives: To further determine the efficacy of low dose methotrexate therapy in adults with new-onset atopic dermatitis or with idiopathic eczema.

Methods: All adult patients with new-onset atopic dermatitis or idiopathic eczema treated by methotrexate in our clinics from 2004 to 2006 were included in the study. All had failed prolonged therapy with oral antihistamines and local corticosteroid creams. Methotrexate, 10–20 mg, was given orally once a week along with folic acid supplements 5 days a week. Additional therapies included predominantly emollients. During the entire treatment period the investigators made global assessments of the clinical response.

Results: Nine patients diagnosed with late-onset atopic dermatitis (n=6) or idiopathic eczema (n=3) were treated with methotrexate. All patients responded to the drug. The initial response was noted after 3–7 weeks. Six patients achieved complete remission after 3 months of methotrexate therapy and three patients had significant improvement. One patient's the condition worsened after achieving a complete response while on methotrexate and it was withdrawn completely. No serious adverse events were noted during treatment.

Conclusions: Low dose methotrexate is an effective therapeutic alternative for late-onset atopic dermatitis or idiopathic eczema in patients unresponsive to local and other systemic therapies.
 

Background: In both adjuvant arthritis and rheumatoid arthritis edema and inflammation appear in synovial joints. Edema or effusion reflects an imbalance in lymph dynamics. Purified micronized flavonoid fraction is mainly used in the treatment of chronic venous insufficiency. This compound improves lymphatic drainage with a signicant increase in lymphatic flow and lymphatic pulsality. It is suggested that the beneficial effect of purified micronized flavonoid fraction may be involved in the treatment of adjuvant arthritis in rats.

Objectives: To evaluate the effect of Detralex on methotrexate prophylactic treatment of adjuvant arthritis in rats.

Methods: Groups of rats with adjuvant arthritis were treated with methotrexate (0.6 mg/kg/week), Detralex (20 mg/kg/day) and their combination for 50 days from adjuvant application. Hind paw swelling, arthrogram scores, serum albumin level, serum nitrite/nitrate concentrations, whole body mineral density and X-ray scans of synovial joints were evaluated as markers of inflammation and destructive changes associated with arthritis.

Results: Long-term prophylactic treatment with low dose methotrexate significantly inhibited the markers of both inflammation and arthritis. Detralex administered alone slightly decreased both the hind paw swelling and the arthritic score. Other inflammatory and arthritic markers were not significantly influenced. However, detralex combined with methotrexate markedly potentiated the beneficial effects of methotrexate, which resulted in a more significant reduction in hind paw swelling, arthritic scores, and serum concentrations of nitrite/nitrate. Interestingly, the arthritis-induced decrease of BMD[1] in AA[2] rats was significantly lower only in the group treated with the combination of Detralex+methotrexate.

Conclusion: Detralex increased the therapeutic efficacy of methotrexate basal treatment in AA. We suggest that this may be related to the beneficial effect of Detralex on microcirculation, especially on venules and lymphatic vessels.

There has been a paradigm shift in the treatment of rheumatoid arthritis in recent years. Early and aggressive treatment with good control of disease activity has improved the prognosis of the disease, however, there is significant variability in the response of patients to different therapeutic agents. Hence it is essential to find the predictors of response to a drug at baseline so that we can avoid the delay in achieving remission and improve the outcome. Here we review the literature on available predictors for treatment response in general and specifically for methotrexate and biological agents. We also look at specific scores or indices that can help predict the response in individual patients.

The addition of methotrexate to treatment protocols in children with acute lymphoblastic leukemia has been found beneficial in preventing central nervous system relapse. However, MTX[1] itself may be associated with neurologic morbidities, the most significant of which is leukoencephalopathy. The present study describes the clinical spectrum of leukoencephalopathy, which ranges from a subclinical disease manifested only radiologically to a progressive, devastating encephalopathy. The interaction of MTX with other components of the treatment protocol is discussed, as is the effect of leucovorin. A summary is presented of the metabolic pathways that may be involved in the development of MTX toxicity. Researchers are still seeking a biochemical marker to aid in the determination of the amount of MTX that may be safely administered.

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There is accumulating evidence that tumor necrosis factor plays a major role in the pathogenesis of rheumatoid arthritis. Recent biotechnological advances have allowed for the development of agents that directly target TNF, a pro-inflammatory cytokine. In the last 2 years, the U.S. Food and Drug Administration and the European Union’s Commission of the European Communities have approved two biological agents for the treatment of refractory RA, etanercept and infliximab. Etanercept is a fusion protein, composed of the Fc portion of immunoglobulin G1 and the extracellular domain of a TNF receptor (p75). Infliximab is a chimeric monoclonal antibody composed of murine variable and human constant regions. In placebo-controlled trials, both agents have proven to be effective and well tolerated in PA patients.