Introduction Patients with Polycystic Liver Disease (PLD) have a wide range of symptom severity and disease course but little is known about the clinical impact of PLD in the UK. The aim of our study was to examine the spectrum of PLD including severity, cyst phenotype, symptoms and treatment in a large, secondary care population over a 10-year period.

Methods We systematically searched radiology reports from 2011-2020 at a major acute hospital serving a catchment population of 675,000. ‘Polycystic’ and ‘multiple cysts’ were used as search terms to identify patients, excluding those without liver or renal cysts. Electronic patient records were interrogated to collect demographics, clinical information and radiology. Images were reviewed to confirm numbers and sizes of cysts.

Results We identified 484 patients with multiple liver cysts; 211 with isolated PLD and 273 with both liver and kidney cysts. Of the radiology images available to view, 133/234 (57%) met the accepted definition of PLD (>10 liver cysts). Overall, 39/484 (8%) had symptoms from hepatic cysts whereas 26/133 (20%) meeting the PLD definition were symptomatic with abdominal pain being the most common symptom (85%). The mean age of first reporting PLD symptoms was 56 (range 36-84 years). Females were a higher proportion of both symptomatic patients (72%) and those requiring treatment (82%). Symptoms correlated with cyst number, occurring in 0-10 cysts 6/101 (6%), 11-20 cysts 6/42 (14%), >20 cysts 20/91 (22%) respectively. Cyst size similarly impacted symptoms and 218/229 (95%) of patients with small (<5cm) liver cysts were asymptomatic. The mean largest cyst size was 4.0 cm (range 0.3-14.8) in asymptomatic people and 8.6 cm (range 4.3-21.0) in those with symptoms. Only 16/484 (3%) received targeted treatment for hepatic cysts with fenestration being the most common procedure performed, followed by resection and liver transplantation. No patients received somatostatin analogues during the study period.

Conclusions This is the largest systematic study of a PLD population from the UK and describes the clinical spectrum of disease. We found patients with multiple simple liver cysts rarely became symptomatic or required treatment. However, defined PLD was more severe in females with a higher rate of symptoms and need for specialist treatment. Symptomatic disease increased when multiple hepatic cysts exceeded 10 in number or grew larger than 5cm. Our data informs the natural history of PLD including the need to access appropriate care for symptomatic disease and highlights the importance of the recently established UK PLD Registry [https://clinicaltrials.gov/ct2/show/NCT04645251].