OBJECTIVE : Systemic lupus erythematous (SLE) is an autoimmune disease which correlate with genetic, immunologic, hormonal, and environmental factors. One of the important environmental factors is vitamin D. This study was aimed to determine and compare the vitamin D level and disease activity in SLE patient. 
METHODS : We perform a cross sectional study of SLE patients from Allergy-Immunology Division, Pediatric Departement, Saiful Anwar Hospital Malang who fulfilled at least 4 American College of Rheumatology (ACR) criteria from February 2018 to February 2019. Disease activity was assessed using SELENA SLEDAI score. SLE patients with SLEDAI score ? 6 were considered to have active disease. Serum 25 Hydroxyvitamin D [25(OH)D] was measured by Enzyme Linked Immunosorbent Assay (ELISA). Vitamin D deficiency was define as < 10 ng/mL, insufficient < 20 ng/mL, and sufficient ? 20 ng/mL. Correlation of serum vitamin D level and disease activity index in pediatric SLE patients were analyzed using the SPSS software with p < 0.05 was significant.
RESULT : Fourteen patients were fulfilled ACR criteria for SLE with median age was 11 years old (range 3-16). There were all female patients. The most common clinical manifestations were rash, arthritis, and fever. Nine patients have active disease with SLEDAI score ? 6. There were 3 patients with deficiency, 5 patients with insufficient, and 6 patients with sufficient vitamin D levels. SLEDAI score in sufficient group (5.00 ± 1.46) was lower than insufficient group (11.67 ± 1.45) and deficient group (16.60 ± 1.99), with p = 0.001. There was also significant correlation between vitamin D level and SLEDAI score (p=0.000, r=-0.893). 
CONCLUSION: There were correlation between vitamin D level and SLEDAI score in pediatric SLE patients