Search

Objective: Methotrexate (MTX) is a disease-modifying antirheumatic drug used in the treatment of rheumatoid arthritis (RA). Genetic polymorphisms of reduced folate carrier (RFC1 A80G), P-glycoprotein (MDR1 G2677T>A/C and C3435T), 5,10-methylenetetrahydrofolate reductase (MTHFR C677T and A1298C), thymidylate synthase (TS 2R-->3R), methionine synthase (MS A2756G) and methionine synthase reductase (MTRR A66G) modify MTX transport and metabolic effects and may influence the treatment response., Methods: A genotyping approach was used to determine the studied polymorphisms in 213 RA patients., Results: We observed that 56 (26.3%) patients discontinued MTX treatment due to poor response and/or toxicity. RFC1 A80G and MDR1 C3435T polymorphisms increased the risk for overall MTX toxicity (P = 0.039, OR = 3.574, 95% CI = 1.065-11.993 and P = 0.032, OR = 7.801, 95% CI = 1.194-50.960 respectively), while MTHFR A1298C polymorphism had a protective effect on overall MTX toxicity (P = 0.027, OR = 0.170, 95% CI = 0.035-0.820)., Conclusion: Our results suggest that genetic polymorphisms in the folate metabolic pathway and MTX transporters modify the toxicity but not the efficacy of MTX treatment.

Objective: Leflunomide is a disease-modifying antirheumatic drug used for treating rheumatoid arthritis (RA). In vitro studies demonstrated that cytochromes P450 (CYPs), mainly CYP1A2 and CYP2C19, might be involved in leflunomide activation. The aim of our study was to investigate whether genetic polymorphisms of CYP1A2, CYP2C19, and CYP2C9 influence leflunomide toxicity., Methods: A genotyping approach was used to determine CYP1A2*1F, CYP2C19*2, CYP2C19*17, CYP2C9*2, and CYP2C9*3 alleles in 105 RA patients., Results: Leflunomide treatment was well tolerated by 62 patients, whereas 43 patients discontinued the treatment within the first year due to toxicity. Patients with CYP1A2*1F CC genotype had a 9.7-fold higher risk for overall leflunomide-induced toxicity than did the carriers of CYP1A2*1F A allele [P = 0.002, odds ratio = 9.708, 95% confidence interval = 2.276-41.403]. No significant association between the CYP2C19 and CYP2C9 genotypes and the leflunomide toxicity was observed., Conclusion: Our results suggest that the CYP1A2*1F allele may be associated with leflunomide toxicity in RA patients.

With the broad employment of immunosuppressive therapy, the incidence of Pseudallescheria boydii infections is rising. We report a first case of the localized subcutaneous P. boydii infection in a patient with microscopic polyangiitis. Favorable outcome related to the treatment with voriconazole adds to the growing body of evidence supporting the use of this particular agent in P. boydii infections.

In a sixty-one-year-old patient with chronic polyarthritis, two life-threatening septic events were observed over a period of 6 months. The patient also had a selective IgG3 deficiency. The susceptibility to infection and chronic polyarthritis observed in this patient were very likely a consequence of the selective IgG3 deficiency.