ESPN 50th Annual Meeting

ESPN 2017

A Retrospective Case Series 1996-2014 of Simple Renal Cysts in Children in a tertiary paediatric centre


Simple renal cysts are increasingly identified on imaging.  We describe their natural history in this case series and propose a clinical and imaging follow up regimen.   

Material and methods:

We performed an ethically approved, retrospective case series of children who had one or two simple renal cysts identified on ultrasound  (USS) from 1996-2014 and who had at least one subsequent USS in our institution. Cases were identified electronically, USS reports were manually read and clinical data extracted from electronic records.  Exclusion criteria included; multicystic dysplastic kidney, autosomal dominant polycystic kidney disease (ADPKD), cystic dysplastic kidneys, more than two cysts, hydronephrosis, tuberous sclerosis and kidney transplant.   


88 patients were identified, 35 (39.8%) were male.  Median age at first USS 8 years (range 10 days-21 years). 79 (89.8%) patients presented with 1 cyst, 9 (10.2%) patients with 2 cysts.  Overall median follow up was 2.6 years (36 days-11.8 years). 

Cysts resolved (definition; not seen on 2 sequential USS) in 10 patients (11.4%).  A further 10 patients (11.4%) had no cyst on 1 repeat USS, but had no subsequent scans.  

10 patients (11.4%) developed further cysts, median time 3.2 years (range 35-days-5years).  Two patients (2.2%) were diagnosed with ADPKD. 

9 patients (10%) developed morphological changes; 7 septations, 1 haemorrhage, 1 complex. Median time 1.5 years (range 50 days to 4.8 years).  3 patients developed calcification, median time 1.3 years (range 1-1.3 years). 

2 patients (2%) were diagnosed with hypertension.  23 patients (26.1%) had an albumin creatinine ratio (ACR) available.  Median ACR 3.25mg/mmol (range 0.3-118.5).  4 patients’ (4%) ACR >30mg/mmol.    


Simple renal cysts spontaneously resolve in 10 – 20% of cases.  A proportion develop further cysts, morphological change, hypertension and proteinuria.  25 patients (28.4%) developed one or more complications.  We recommend at least 3 ultrasound scans and 5 year follow up with regular blood pressure and ACR measurements.