Vitamin-D deficiency is encountered in almost all egyptian stage 3-5 chronic kidney disease patients in spite of the sunny weather.

Currently, there is no available data about Vitamin D status among Egyptian chronic kidney disease (CKD) patients. This cross-sectional study is looking for the prevalence of Vitamin D deficiency among Stage 3a-5 CKD Egyptian patients and its possible associations. We studied 1624 Stage 3a-5 CKD adults (689 males and 935 females) together with 200 normal control persons. All the recruited candidates were tested for body mass index (BMI); serum levels of blood urea nitrogen, creatinine, calcium (Ca), phosphorus (P), parathyroid hormone (PTH), 25 hydroxy vitamin D (25(OH)D), albumin, and uric acid (UA); urine albumin/creatinine ratio (ACR), and estimated glomerular filtration rate. The optimal level of Vitamin D was encountered in only 1.4% of CKD patients versus 52% of the normal controls. A total of 1107 (68.2%) CKD patients versus 23 (11.5%) controls had serum 25(OH)D <20 ng/mL (mean ± standard deviation = 16.8 ± 5.8 versus 37.3±7.6 ng/mL for CKD versus control group, respectively, P <0.001). There was a highly statistically significant positive correlation between serum 25(OH)D and serum Ca (r = 0.299, P <0.001) and a highly statistically significant negative correlation between serum 25(OH)D on the one hand and serum P, serum PTH, serum UA, and urine ACR on the other hand (r = -0.46, -0.69, -0.73, and -0.8, respectively, P <0.001). Vitamin D deficiency is very common among Egyptian CKD patients. Serum P, UA, and urine ACR ratio are the most important variables which are found to be negatively associated with serum 25(OH)D.