Erythropoietin-producing renal cyst and polycythemia vera

Erythropoietin in polycystic kidneys.

“…This agrees with the concept that a higher EPO production is a major reason for the less severe anemia in these patients. It is thought that the cystic kidneys are the source of EPO in ADPKD (7,8) and both our findings that cysts sometimes contain enormous amounts of biologically active EPO and that arteriovenous concentration differences of EPO were seen in five kidneys further support this idea. However, the intrarenal production site of EPO in the cystic kidneys is so far unknown.…”

“…Interestingly, the degree of anemia is strikingly moderated if ADPKD is the reason for renal insufficiency (3)(4)(5)(6). Based on the observations that serum EPO levels in patients with ADPKD are on average twofold higher than in end-stage renal disease of other causes (4)(5)(6) and that renal cysts may contain erythropoietic activity (7,8) it is assumed that an improved 1. Abbreviations used in this paper: ADPKD, adult dominant polycystic kidney disease; EPO, erythropoietin.…”

Reversible Erythrocytosis in a Patient with a Hydronephrotic Horseshoe Kidney

“…Erythrocytosis as a result of increased EPO production has been reported in patients with hydronephrotic or polycystic kidneys, solitary renal cysts and renal cell carci nomata [1][2][3], Our patient had dystrophia myotonica and was found to have erythrocytosis due to increased EPO production by a hydronephrotic moiety of a horseshoe kidney. The association of rare neurological syndromes with renal ectopia or cystic diseases of the kidney has been documented [4] and it is possible that our patient is another such example.…”

Management of Renal Cystic Disorders

“…Benign renal cysts have been associated with erythrocytosis, and in a few instances increased amounts of erythropoieten have been isolated from the cyst fluid (225)(226)(227). In one patient the erythrocytosis remitted after decompression of the cysts (228).…”