Hello,
Without being able to see the skin I can't say for certain, but if he had
high blood pressure and if there has been swelling of the bottoms of his legs (you mention that the skin is tight), the discoloration may be "brawny induration" from stasis
dermatitis.
This happens when there is swelling in the lower legs and over time, pigment from the blood stains the skin. Treatment is to address the cause of the swelling in the legs (is it due to congestive heart failure? or to deep varicosities?).
Elevating the legs frequently, not standing on them for long periods of time, and wearing compression stockings (fit specifically for him) may help if venous stasis dermatitis is the problem. And if there is congestive heart failure, he may need a
diuretic.
To help prevent skin break down, use a good emolient to keep the skin moisturized and supple, such as
Eucerin.
Hope I have answered your query. Let me know if I can assist you further.
Regards,
Dr. Bonnie Berger-Durnbaugh, General & Family Physician