Caliceal diverticulum in pediatric patients: the spectrum of imaging findings

Background Caliceal diverticulum (CD) is uncommon in children. As compared to adults, most children with CD are symptomatic. Common complications include stone formation and infection. Correct diagnosis of CD is important for guiding management. Objective To identify imaging findings at diagnosis and follow-up in pediatric patients with CD. Materials and methods We identified all patients from 2003 to 2010 with a diagnosis of CD. We reviewed presenting symptoms, underlying diseases, complications, management, and all pertinent radiological examinations. Results Twenty-four patients (2.6 to 18.5 years old, 11 females) had CD. Urinary tract infection was the most common (n = 8) presentation. Diagnosis of CD was based on delayed post-contrast CT in 79% of patients with only one false-negative CT. Most patients (n = 20) had a single CD; others had either 2 CDs (n = 2) or multiple CDs (n = 2). CD diameter ranged from 1.0 to 18.3 cm and grew in five of nine patients who had follow-up studies. Seven patients developed stone in the CD. Fifteen patients (63%) underwent a surgical procedure. Conclusions CD is commonly solitary, often grows with time and may mimic other diagnoses, including simple cyst, complex cyst and polycystic kidney disease. Delayed postcontrast CT is highly sensitive in diagnosing CD.