Cyst Infections in Patients with Autosomal Dominant Polycystic Kidney Disease

Background and objectives: Cyst infection is a complex diagnostic and therapeutic issue in patients with autosomal dominant polycystic kidney disease (ADPKD); however, published data regarding the diagnosis and the management of cyst infections in patients with ADPKD are sparse.Design, setting, participants, & measurements: A retrospective study was conducted in a referral center for patients with ADPKD in Paris, France. We identified using a computerized database all patients who had ADPKD and were admitted in the nephrology department of Hôpital Necker between January 1998 and August 2008 with likely or definite renal and/or hepatic cyst infection. Medical files of all included patients were reviewed.Results: Among 389 identified patients with ADPKD, 33 (8.4%) had 41 episodes of cyst infection, including eight definite and 33 likely cases. The incidence of cyst infections in patients with ADPKD was 0.01 episode per patient per year. Microbiological documentation was available for 31 episodes (75%), Escherichia coli accounting for 74% of all retrieved bacterial strains. Positron emission tomography scan proved superior to ultrasound, Computed tomography scan, and magnetic resonance imaging for the detection of infected cysts. Clinical efficacy of initial antibiotic treatment was noted in 71% of episodes. Antibiotic treatment modification was more frequently required for patients who were receiving initial monotherapy compared with those who were receiving bitherapy. Large (diameter >5 cm) infected cysts frequently required drainage.Conclusions: Positron emission tomography scan will probably make the diagnosis of cyst infections easier and more accurate. Antibiotic association, including a fluoroquinolone, and the drainage of large infected cysts remain the main treatment for cyst infections.Autosomal dominant polycystic kidney disease (ADPKD) represents the most common inherited disorder affecting one in 500 to one in 1000 live births and accounting for 4 to 10% of dialysis patients. The most striking feature of ADPKD is the occurrence of numerous renal and hepatic cysts, which arise from various renal tubule segments and lead to an increased kidney size. Cysts are also associated with some of the most common complications of ADPKD: Intracystic bleeding, gross hematuria, obstruction mainly caused by liver cysts, and, most important, infections. Kidney and liver cyst infection is a complex diagnostic and therapeutic challenge; however, the literature on the diagnosis and the management of urinary tract infections and particularly cyst infections in patients with ADPKD is relatively sparse. The clinical, microbiological, and radiologic features of cyst infections as well as treatment regimens remain ill-defined (1–3). We conducted a retrospective, single-center study to assess the clinical and radiologic presentation and treatment outcomes of cyst infections in patients with ADPKD.