<prompt> An 8-month-old boy is referred for evaluation following a urinary tract infection. Ultrasound examination of the abdomen is normal. The most appropriate investigation to evaluate his lower urinary tract isRadionuclide cystogramMicturating cystourethrogramIntravenous pyelogramCystoscopy  <response>: Diagnostic imaging studies following UTI Recommended radiological evaluation includes a combination of ultrasound abdomen, micturating urethrogram MCU, most appropriate and radionuclide renal scan. Detailed radiological investigations are performed on all children: 1. Below 3-year-old with first UTI 2. Those with symptoms of pyelonephritis 3. Recurrent UTI 4. Abnormal voiding 5. Family history of UTI or hypeension. Procedure The estimated age-adjusted bladder capacity can be calculated using : linear equations: 1 year weight x 7 capacity mL 2.5 x age 38 capacity mL 2 years: age years 2 x 30 capacity mL 6 2 years: age 26 x 30 capacity mL non-linear equations: 4.5 x age 0.40 x 30 capacity Reference: GHAI Essential pediatrics, 8th edition 