Badr AMM, et al. - In this current study, the physicians aimed to apply interleukin 22 binding protein (IL-22BP) as a non-invasive marker for disease activity in juvenile systemic lupus erythematosus (JSLE) and lupus nephritis (LN). They suggested that urinary IL-22BP might be used as a non-invasive marker for assessment of disease activity in children with JSLE and LN.

Methods

• This study consisted of 82 subjects: 51 JSLE patients and 31 healthy controls of matched age and gender.
• With enzyme-linked immunosorbent assay, urinary IL-22BP was measured.
• Urinary IL-22BP level was correlated with different clinical and laboratory data in JSLE as well as Systemic Lupus Erythematous Disease Activity Index 2000 (SLEDAI-2k), renal SLEDAI-2k, and Systemic Lupus International Collaborating Clinics (SLICC) renal activity score which were used to assess overall disease and renal activity.

Results

• Investigations displayed that urinary IL-22BP level was significantly higher in JSLE patients with mean level of 4.13 ± 1.10, as compared to controls 1.63 ± 0.61 (P value < 0.001).
• Patients with active LN had urinary levels of IL-22BP (5.47 ± 1.03) higher than patients with active JSLE without LN (4.23 ± 0.72) and patients with non-active JSLE/LN (3.5 ± 0.65) with a highly significant P value < 0.001.
• Moreover, there was a positive correlation with SLEDAI-2k, renal SLEDAI, and renal activity scores (P < 0.001).