Background: chronic kidney disease (CKD) is one of the leading cause of death among the Palestinians. Although vitamin D deficiency has been recently linked to CKD, biochemical tests in Gaza hospitals and clinics are restricted to monitoring kidney function by routine tests. Therefore, introducing vitamin D test for CKD patients may be helpful in understanding patient’s condition and help in disease management. Objective: To assess serum vitamin D level in CKD patients from Gaza Strip. Material and methods: This case-control study comprised 42 CKD patients and 42 healthy controls. Patients were taken from Kidney unit in Al-Shifa hospital and Nasser Medical Complex in Gaza Strip. Controls were selected from the general population. Questionnaire interview was applied. Serum vitamin D, urea, creatinine, uric acid, glomerular filtration rate (GFR), total protein, albumin, globulin, calcium and phosphorus were determined. Data were analysed using SPSS version 18.0. Results: The mean ages of cases and controls were 55.3±8.6 and 54.9±8.2 years, respectively. CKD was more frequent among unemployed individuals, families with low income as well as among families with history of CKD (P<0.05). The mean levels of vitamin D were significantly lower in cases compared to controls (29.7±12.9 versus 35.2±9.9 ng/dl, P=0.033). Serum urea, creatinine and uric acid were found to be significantly higher in cases (84.6±47.4 and 1.90±1.20 and 7.92±2.29 mg/dl, respectively) compared to controls (35.7± 13.5 and 0.81±0.27 and 5.18±2.31 mg/dl) with P=0.000. In contrast, The mean value of GFR was significantly declined in cases compared to controls (62.4±32.5 versus 124.6±45.4, P=0.000). There was a significant decrease in serum total protein and albumin in cases compared to controls (7.0±0.5 and 5.2±0.40 versus 7.3±0.6 and 5.4±0.59, P=0.005 and P=0.023, respectively). Serum calcium was significantly declined in cases compared to controls, whereas serum phosphorus showed none significant increase in cases (8.61±0.77 versus 9.12±0.69, P=0.003 and 4.72±0.94 versus 4.49±0.85, P=0.239, respectively). Vitamin D level was found to be significantly lower in individuals with family history of CKD (P=0.038). Vitamin D levels were positively correlated with GFR (r=0.258, P=0.020), total protein (r=0.283, P=0.011), albumin (r=0.278, P=0.012), globulin (r=0.159, P=0.156) and calcium (r=0.562, P=0.001) and negatively correlated with urea (r=-0.302, P=0.005), creatinine (r=-0.343, P=0.001), uric acid (r=-0.249, P=0.022) and phosphorus (r=-0.168, P=0.125). Conclusions: Serum vitamin D levels were significantly lower in CKD patients compared to controls. Vitamin D levels were lower in individuals with family history of CKD. Vitamin D levels were positively correlated with GFR, total protein, albumin, globulin and calcium, and negatively correlated with urea, creatinine, uric acid and phosphorous
