There are many reports about development of AC in patients on dialysis therapy (DT) and about their pathophysiological consequences. The aim of our studies was to determine the prevalence of AC in patients treated with hemodialysis in dialysis centre in Gdańsk. We also tried to asses relationship between the presence of AC, age and sex of the patients, the duration of DT and level of haemoglobin (Hb), hematocrit (Ht), red blood cells (RBC) and the prevalence of hypertension (H). Renal ultrasound scan was performed in 54 patients, among them 26 (48.5%) had acquired cysts. No correlation was found between presence of cysts and age, sex and nature of the underlying renal disease. There was a positive correlation between the prevalence of AC and the duration of DT (DT < 1 year--36.8/, DT < 3 years--42.8%, DT > 3 years--59%), it did not, however, reach statistical significance. Haematological parameters did not differ significantly between both groups, AC--patients, however, received more blood transfusions (2983 ml/year vs. 2485 ml/year). Similarly, there were no differences in systolic and diastolic blood pressures (mean yearly values before and after HD) between both groups, but in AC+ group more patients needed intensive treatment with hypotensive drugs. Our results indicate that the prevalence of AC increases with the duration of DT. The possibility that the presence of AC may influence severity of anaemia and hypertension is suggested.