Managing cyst infections in ADPKD: an old problem looking for new answers.

Kidney and liver cyst complications are frequent in patients with autosomal dominant polycystic kidney disease (ADPKD). It has been estimated that 30 to 50% of patients with ADPKD experience some form of kidney infection during their lifetime (1,2). Patients may experience symptoms from cyst infections, cyst hemorrhage, or pain from ruptured or expanding cysts. The clinical determination of an infected kidney cyst may be difficult in a patient with ADPKD. The typical presentation of fever and abdominal pain carries a broad differential that includes pyelonephritis, infected kidney stones, perinephric or perihepatic abscess, cyst hemorrhage, or even intra-abdominal pathology unrelated to ADPKD. Conventional imaging with ultrasound, computed tomography, or magnetic resonance imaging scan may not be definitive in isolating the location of infection or even in differentiating cyst infection from cyst hemorrhage or pyelonephritis (3). A urine culture is often negative because kidney cysts become separated from their parent nephron, and one must rely more on blood cultures or cyst fluid aspiration when they can be obtained. The accurate diagnosis of cyst infection is of great importance, because it can influence the prompt initiation of antibiotics (particularly one that is widely known to penetrate cyst membranes), it can determine the need for extending the duration of antibiotic …