Burkitt lymphoma, a type of non-Hodgkin B-cell lymphoma, is the fastest growing human cancer, presenting pathologically with a ‘starry sky’ pattern. It is most often found in the abdomen and the jaw, however, localization in the...

Background: Nonalcoholic fatty liver disease (NAFLD) is common in rheumatoid arthritis (RA), and methotrexate (MTX) use raises concern about hepatotoxicity. We evaluated whether HLA-DRB1, PNPLA3, SLCO1B1, and MTHFR variants are associated with NAFLD, liver fibrosis, or MTX toxicity/pharmacokinetics in RA, after accounting for clinical covariates. Methods: In a cross-sectional cohort of 159 patients with RA, NAFLD, and fibrosis were assessed by FibroScan (CAP ≥ 275 dB/m; LSM > 8 kPa). We compared baseline characteristics by NAFLD status and fitted multivariable models for NAFLD, fibrosis, ALT elevation, and MTX toxicity; MTX pharmacokinetics were analyzed in 111 MTX-treated patients. Multiple testing was controlled using the Benjamini–Hochberg method. Results: The prevalence of NAFLD was 36%, and that of fibrosis was 11%. NAFLD patients had higher CAP and LSM, and markedly greater adiposity indices (body weight, BMI, waist and hip circumference, WC). BMI and WC were independently associated with NAFLD (BMI OR 1.27 per kg/m², 95% CI 1.16–1.40; WC OR 1.06 per cm, 95% CI 1.01–1.12). No HLA-DRB1, PNPLA3, SLCO1B1, or MTHFR variant showed an association that survived multiple-comparison correction. Among MTX users, 21/111 (19%) experienced toxicity. SLCO1B1 and MTHFR variants did not influence MTX pharmacokinetics; age was associated with lower dose-normalized MTX exposure, and cumulative dose was positively associated with exposure. Conclusions: In RA, adiposity—not the tested candidate pharmacogenes—drives NAFLD risk, and SLCO1B1/MTHFR variants do not support MTX dose adjustment. The findings emphasize routine clinical risk factors over single-gene testing for NAFLD and MTX hepatotoxicity in this setting.

Background/Objectives: This observational study investigated associations between human leukocyte antigen (HLA) polymorphisms and imaging-defined hepatic steatosis (non-alcoholic fatty liver disease—NAFLD) and liver fibrosis in patients with rheumatoid arthritis (RA). Methods: Steatosis was assessed by transient elastography (FibroScan) and defined as controlled attenuation parameter (CAP) ≥ 275 dB/m; fibrosis was defined as liver stiffness measurement ≥ 8 kPa. We tested 11 frequent HLA alleles (HLA-A*02, HLA-B*07, HLA-B*08, HLA-B*27, HLA-B*35, HLA-B*44, HLA-B*51, HLA-DRB1*11, HLA-DRB1*14, HLA-DRB1*15, and HLA-DRB1*16). Associations were evaluated using multivariable logistic regression (individual and omnibus models) adjusted for age, body mass index (BMI), triglycerides, and glucose. Results: A total of 176 patients with rheumatoid arthritis were enrolled. NAFLD/steatosis was present in 35.2% of patients (n = 62), and fibrosis in 10.8% (n = 19). No HLA allele was significantly associated with steatosis or fibrosis after correction for multiple testing. BMI and triglycerides were independently associated with steatosis (BMI OR 1.22, 95% CI 1.12–1.34; triglycerides OR 1.48, 95% CI 1.04–2.18). For fibrosis, HLA-DRB1*15 showed the strongest trend-level association (OR ~2.6–2.9) but did not remain significant after correcting for multiple testing. Conclusions: In this RA cohort, metabolic factors (particularly BMI and triglycerides) were the dominant predictors of CAP-defined steatosis. No robust association between the tested HLA markers and steatosis or fibrosis was identified. Trend-level signals—most notably HLA-DRB1*15 for fibrosis—should be considered hypothesis-generating and warrant replication in larger, adequately powered cohorts.