Q: My father-in-law is diabetic for more than 10 years and he is 72 years old. Last month, he felt sick with swelling in the abdomen and ankles. We admitted him in the hospital and the doctors diagnosed chronic renal failure. The creatinine level was 1.8, urea was 90, calcium - 12.5. After he was discharged, we took him to a nephrologist and he performed a renal biopsy. The biopsy result showed that he was suffering from chronic diabetic nephropathy. The nephrologist said that this stage was not reversible but said he would treat him the best he can. The nephrologist advised us to take all the urine and blood tests and meet him after 10 days. Yesterday, we took blood and urine tests but the results showed normal values for all parameters. The creatinine was 1.3, urea 38 and calcium 10.2. Also, other parameters like sodium, potassium were normal. I am surprised to see such a result. Has renal failure been reversed? Is he not suffering form any renal malfunctioning any more? Please advise how we should take care of him?

A:The results are not surprising. Undoubtedly, your father-in-law has changes of chronic diabetic nephropathy, which is a progressive disorder. Serum creatinine and urea are indirect functional correlates of the structural changes in the kidney. Many times there is poor co-relation and functional deterioration may come later or early. Moreover, there are others factors (some which are reversible), which could affect kidney function. It is possible that such factors may have been responsible for deterioration and its reversal led to improvement. One also has to keep in mind the laboratory variation of S. creatinine and urea, especially if done in different labs as standardisation can be a problem. Your father-in-law requires to keep his blood pressure target around 120/75 mm Hg, preferably use ACEI/ARF (in consultation with your nephrologist), keep his target HbA1C (7%) done every 3 months and avoid smoking to slow down the rate of natural deterioration of kidney function in diabetic kidney disease.