Please select the eligibility criteria that correspond to the clinical trial below.
Title: Metabolic Acidosis and Its Impact on Mineral Metabolism and Physical Performance in Renal Transplant Patients
Brief Summary: Acidosis (accumulation of acid in the body) may be an underrecognized problem in patients after renal transplantation. It may have consequences on physical performance due to negative effects on bone and muscle metabolism.

Therefore, the purpose of this study is

1. to determine the status of physical capacity and bone structure in renal transplant patients with metabolic acidosis
2. to study the effect of substituting base equivalents (citrate) on acid/base status of renal transplant patients with acidosis
3. to compare the status of physical capacity and bone structure in renal transplant patients with metabolic acidosis before and after substitution with citrate


Options:
A: Inclusion Criteria:

* Recipients of a deceased donor kidney transplant at least 3 months after transplantation
* Urinary protein to creatinine ratio (UPCR) \> 200 mg/g (20 mg/mmol) as determined by the the mean of three second morning void urine specimens
* Subject is on stable immunosuppression for at least 3 months
* Subject is on stable doses of antihypertensive medications for at least 3 months
* Subject is not expected to begin dialysis for at least 6 months
* Estimated glomerular filtration rate \> 15 ml/min/1.73 m2
* Corrected serum calcium level \< 2.6 mmol/l
* Intact parathormone value \> 30 pg/ml

Exclusion Criteria:

* Subjects on vitamin D receptor activation therapy within 3 months prior to the first study visit
* Acute kidney injury within 3 months of the first study visit
* Subjects with poorly controlled hypertension
B: Inclusion Criteria:

1. First or second kidney transplant recipients, aged 18-75 years, PTH \> 150 pg/ml
2. De novo patients scheduled to receive ciclosporin A and prednisolone based immunosuppression.

Exclusion Criteria:

1. Previous or current bone disease unrelated to end stage renal failure.
2. Patients with PTH \< 150pg/ml who may be at risk of adynamic bone disease.
3. Treatment at any time with a bisphosphonate.
4. d. Calcitonin treatment during the previous month.
5. Malignancy (current or history within last 5 years)
6. Pregnancy or lactation, or women of childbearing potential unwilling to use an effective form of contraception for the 12 month duration of the study.

Protocol-defined inclusion/exclusion criteria may apply.
C: Inclusion Criteria:

* age \> 18
* deceased donor kidney transplant recipients
* only kidney transplant recipients
* vitamin D deficiency defined as 25 (OH)D \< 50nmol/l

Exclusion Criteria:

* re-transplantation for the second time if the patient is highly immunized and therefore included in the aphaeresis program
* re-transplantation for the third or further time
* significant impaired intestinal resorption: malabsorption due to celiac sprue, systemic scleroderma; maldigestion due to chronic pancreatitis, pancreatic insufficiency, pancreas resection, mucoviscidosis, Zollinger-Ellison-syndrome
* history of inflammatory bowel disease: Crohn's disease, ulcerative colitis
* previous gastrectomy, small bowel or large bowel resection, intestinal bypass surgery
* severe liver disease: cirrhosis
* HIV positive
D: Inclusion Criteria:

* Patients with a renal graft having been transplanted within the previous 8 years and being at least 3 months post transplantation, or, patients scheduled to undergo transplantation from a living organ donor within the upcoming 3 months
* Venous serum bicarbonate concentration \< 24 mmol/L at time of baseline determination
* Renal transplant function with a calculated glomerular filtration rate (GFR) greater or equal 30 ml/min according to the Cockcroft-Gault formula
* Immunosuppressive therapy including a calcineurin inhibitor (cyclosporine A or tacrolimus)
* Age 20 through 65 years of either sex
* Written informed consent for study participation

Exclusion Criteria:

* Acute rejection episode requiring specific therapy within 4 weeks before study inclusion
* Severe impairment in general health and/or physical handicaps (malignant neoplasia, catabolic state, acute systemic infection requiring therapy)
* Mental illness, psychiatric disorder
* Tetracycline intolerance
* Planned or "overt" pregnancy

Answer: D