Hi,

Thank you for the query.

I wanted to know a few more things:
- What is the reason for renal failure and how bad is the serum creatinine?
- Are you losing weight by any chance?
- What is the heart problem like - is it ischemic heart disease or heart failure following that?

Darkening of skin is associated with the following:
- Dark pigmentation of skin is seen in renal, hepatic (liver) and heart failure.
- If you are losing weight with some kind of weakness in body then lower serum cortisol can be a reason for dark pigmentation.
- Any kind of acute stress also makes you dark
- If you are losing weight with some kind of palpitations and tremors in body, excess sweating etc exist then it can be something call 'hyperthyroidism' where you get functional 'hypocortisolism' and this leads to dark pigmentation.
- Having very low vitamin B12 levels in the body is another reason.

In brief you will need to be evaluated to know the cause of darkening. If any of the below test is done recently (in last 3 months), please let me know the results. Else, the below tests are in order.
- Thyroid Stimulation Hormone (TSH).
- Free T4
- Serum Cortisol- blood sample given in fasting, at 8 AM and not beyond that
- Serum Vitamin B12 levels
- Serum creatinine
- Serum sodium
- Serum potassium
- Liver function tests
- Hemoglobin

This will give us lead to find a reason for such a sudden onset of dark pigmentation of the skin. So please revert back with these reports.

Hope this answers your query. Let me know if you have any other enquiries.

Regards

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