The safety and efficacy of Caltriol on mild proteinuria (<1.0g/d) reduction in CKD patients.

Proteinuria is not only a capital sign of kidney disease, but also a marker of chronic kidney disease (CKD) progression. Emerging evidence in patients with CKD show that vitamin D and its analogs can reduce proteinuria or albuminuria in the presence of angiotensin-converting enzyme inhibithion. While some of the studies reported that vitamin D receptor activation has been associated with increased serum creatinine and reduced estimated glomerular filtration rates. Therefore, the investigators plan to conduct a randomized clinical study to evaluate the efficacy and safety of Calcitriol in the treatment of mild proteinuria (<1.0g/d) CKD patients,which has no specific treatment at present.

Inclusion Criteria:

• aged 18-75 years
• clinical diagnosed and/or biopsy-confirmed primary glomerulonephritis
• proteinuria 0.15-1.0 g/d in 2 consecutive samples within 4 weeks despite ACE inhibitor (ACEI) or angiotensin receptor blocker (ARB) treatment for at least 1 year or ACEI/ARB withdrawal because of of drug intolerances (low blood pressure, cough, hyperkalemia) for at least 1 month
• estimated glomerular filtration rate (eGFR)>60ml/min/1/73m2
• corticosteroid and immunosuppressive agents withdrawal for at least 6 months
• normal blood pressure
• serum intact parathyroid hormone (iPTH) level >20pg/mL
• corrected serum calcium level < or = 2.55 mmol/L
• serum phosphorus level < or = 1.68 mmol/L
• 24 hours urinary calcium excretion level < or = 7.5 mmol
• not receive treatment of vitamin D or its analogue within 6 months
• willigness to give written consent and comply with the study protocol

Exclusion Criteria:

• history of sensitivity or allergy to calcitriol or other vitamin D analogs
• pregnancy, lactating women
• history of severe coexisting disease such as, but not limited to, chronic liver disease, myocardial infarction, cerebrovascular accident, malignant hypertension
• history of malignancy
• history of extraskeletal calcification, hyperuricemia, gout, kidney stone, gall stone, bone diseases
• patients receiving drugs contains of calcium
• patients receiving cimetidine, trimethoprim, or other drugs which can increase tubular creatinine reabsorption
• participation in any other trials within 1 month
• history of non-compliance