Renal Cysts

[CandiceC]

I am a 48 year old woman who had several severe kidney infections in my left kidney beginning about 25 years ago.  The urologist indicated I had a renal reflux in that kidney.  I experience only a few infections since and very small stone(s) about ten years ago in that kidney.  Now I've had UTIs again, with frequent left flank pain, fatigue.  A urologist performed a cystoscopy a few months agao and said I have a grfade 5 left reflux.  The nephrologist did a CT that showed cysts on both kidneys that are 16 (R) and 20 mm (L).  The nephrologist said that the cyst on the left is complex and septated with many interior walls. I'm scheduled for a VCUG and US in a couple of weeks.  Lab work indicates my C3c level is low (50).  Other tests are fine so far.  I take lithium as well for mild bipolar disorder, the nephrologist believes I should get off this drug and get on something else due to some kind of problem in the kidneys that can occur after long term use.  

The left flank pain is quite frequent and painful, but he says probably not due to the cysts.  Can the cyst cause the pain, can it be eliminated and what is recommended to make sure this cyst does hot become cancerous?  Is the C3c related to this problem?  IS it generally recommended to stay off lithium?

[Kevin Pho, MD]

Simple renal cysts are the most common renal masses, accounting for roughly 65 to 70 percent of cases.  They typically produce no symptoms and are discovered incidentally by radiological examination. In one study of over 1000 patients, for example, there was no increase in the incidence of hypertension, flank pain, hematuria, or proteinuria when compared to matched controls without cysts.  If the cysts are indeed simple cysts, I am not aware of a connection to cancer.  

I am also not aware of a connection between a low C3 level and kidney cysts.  Regarding Lithium, nephrogenic diabetes insipidus is the most common associated kidney disease, but renal tubular acidosis, the nephrotic syndrome, and a chronic interstitial nephritis have also been described.  If you are having documented kidney damage, you may want to discuss with your personal physician about stopping the Lithium.

Followup with your personal physician is essential.

This answer is not intended as and does not substitute for medical advice - the information presented is for patient education only. Please see your personal physician for further evaluation of your individual case.

Thanks,
Kevin, M.D.

Bibliography:
Rose.  Renal toxicity of lithium.  UptoDate, 2004.
Rose et al.  Simple renal cysts and evaluation of a renal mass in adults.  UptoDate, 2004