Brief Answer:
collection of fluid in kidney.various types,causes,problems detailed below.

Detailed Answer:
Hello and welcome to Ask A Doctor services.
I have read your query and here is my advise.

* The issue is having multiple medical complex material, but here I have tried to make
it as much simple as possible for you.

* The renal cyst is basically a collection of fluid involving part of kidney, usually surface
in beginning and later other parts of the kidney.

* These are non cancerous condition of the kidney and can be of 2 broad categories as
simple or complex cysts.

* Simple cysts are
- usually isolated, single, unilateral ( involving one kidney )
- causes of no symptoms and found accidentally
- usually does not require treatment
- not associated with other systemic issues

* Complex cysts
- usually multiple, various size
- can be associated with cyst at other body organs as liver or else
- can present with various symptoms of high BP, varying pain, abdomen fullness or
others

* Causes
- simple cyst etiology is not clear, though partial erosion of surface of kidney from
cell damage and giving rise to diverticulum type thing with collection of fluid
- multiple cysts are in many cases hereditary ( derived from genes ) and sometimes
sporadic ( without inheritence )

* Complications of the renal cysts
- may remain asymptomatic and without problems for long period of times
- may enlarge, give pain in renal angle, dysuria, infection, stone formation, rupture, high BP
and some cases may progress to kidney failure

* Above is the gross derivation of general presentation in clinics, there are innumerable
variations which can show up in different cases as well.

* Detailed evaluation require precise medical history, physical examination, kidney
function tests for creatinine and others to figure out the management.
Most vital is control of BP and blood sugar levels.

Hope this information will help you to understand the condition and I would like to discuss your further doubts regarding the same.

Wish you best health and recovery.
Regards.

Dr Bhagyesh

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