Brief Answer:
There are many causes for kidney problems.

Detailed Answer:
Hello and welcome,

I think you are asking what illnesses cause decreased kidney function? (Or are you asking what symptoms to expect?)

There are many causes. Is your decreased kidney function being investigated as to the cause?

Here are some possible causes for decreased kidney function:

Diabetes (can cause diabetic nephropathy)

High blood pressure (hypertension), if not controlled, can damage the kidneys over time.

Infections (kidney problems can happen after certain types of infections)

Lupus

Hereditary problems such as polycystic kidney disease (less common)

Certain medications including ibuprofen and other NSAIDs.

Atherosclerosis (deposits in the arteries can interfere with the kidneys getting the blood they need)

Urinary tract stones and tumors can obstruct urine flow to the bladder and cause kidney problems.

Sickle cell disease (more common to people of XXXXXXX or African-American origin)

Drug abuse.

Chronic kidney infections.

HIV

Please let me know if I can provide further information or clarification. The more information and history you can provide, the more specific I can be in my response.

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