MALT1 serves as a biomarker for estimating disease risk of lupus nephritis: a prospective case-control study

BACKGROUND: Mucosa-associated lymphoid tissue lymphoma translocation protein 1 (MALT1) regulates immune/inflammation response and kidney injury, indicating that it might participate in the lupus nephritis (LN) pathology. The present study sought to investigate the utility of MALT1 serving as an indicator of severity and inflammation biomarker in LN. METHODS: In total, 30 LN patients and 30 non-LN systemic lupus erythematosus (SLE) patients were recruited, and blood MALT1 expression was detected using reverse transcription-quantitative polymerase. Besides, the SLE disease activity index was calculated for all subjects to assess disease activity. RESULTS: MALT1 was more increased in LN patients than non-LN SLE patients {2.26 [interquartile range (IQR): 1.38–3.54] vs. 1.04 (IQR, 0.60–1.62); P<0.001}. Additionally, the multivariate logistic regression model analysis indicated that higher MALT1 [odds ratio (OR): 3.097, 95% CI: 1.292–7.425, P=0.011] and higher serum creatinine (Scr) (OR: 1.055, 95% CI: 1.012–1.099, P=0.011) were independently related to an elevated risk of LN. The MALT1 and Scr-based nomogram exhibited a good value in estimating LN risk with an area under the curve (AUC) of 0.873 (95%CI: 0.787–0.960). MALT1 was highest in LN patients with class IV (accompanied by V or not), followed by class V and class III (accompanied by V or not) patients, and lowest in class II patients (P=0.046). MALT1 was positively linked to the LN activity index (r(s)=0.370, P=0.044); however, while it was positively associated with the LN chronicity index, the level did not reach statistical significance (r(s)=0.341, P=0.066). MALT1 was positively linked to 24 h proteinuria (r(s)=0.473, P=0.008), Scr (r(s)=0.378, P=0.039), and C-reactive protein (CRP) (r(s)=0.410, P=0.025) in LN patients. CONCLUSIONS: MALT1 might serve as a useful biomarker for estimating the disease risk in LN patients; however, future large-sample size studies need to be conducted to validate our findings.