Pyelonephritis: Diagnostic Tests

Obligatory medical device diagnostics.

  • Renal ultrasonography (ultrasonography of the kidneys) – as a basic diagnostic test [widened, echo-poor parenchymal fringe may be apparent; evidence of complicating factors such as urinary stones, urinary retention, abscess formation (formation of a pus cavity), residual urine formation, if applicable]Note: Only in circa 50% of all acute pyelonephritides is a pathologic (deviating from the norm) sonogram found.In infants, increase in renal volume (> 2 SD) is an indication of probable pyelonephritis.

Optional medical device diagnostics – depending on the results of the history, physical examination, laboratory diagnostics and obligatory medical device diagnostics – for differential diagnosis.

  • X-ray abdomen review – to exclude concomitant diseases.
  • I.v. pyelogram (synonyms: IVP; i.v. urogram; urogram; i.v. urography; excretory urography; excretory pyelogram; intravenous excretory urogram; radiographic imaging of the urinary organs or urinary tract system) – to exclude urinary outflow disorders.
  • Micturition cystourethrography (MZU; examination method in which the urinary bladder and urethra before and during micturition with the help of contrast media in the context of an X-ray examination are represented) or sonographically as micturition sonography (MUS) – to exclude or detect a vesicoureteral reflux (VUR; unphysiological reflux of urine from the bladder via the ureters (ureters) into the renal pelvis).
  • Color Doppler sonography (color-coded Doppler sonography; medical imaging technique that can dynamically visualize fluid flows (especially blood flow))
  • Magnetic resonance (MR) urography – when complex malformations of the kidney are suspected; may also be used to assess renal function, drainage ratios, and scarring in the renal parenchyma
  • Computed tomography (CT) of the abdomen (abdominal CT) – if abscess formation is suspected.
  • Renal scintigraphy:

Urinary tract infection (UTI) in childhood

The aim of medical device diagnostics in urinary tract infection (UTI) in childhood:

  • To detect anatomic abnormalities that promote the infection:
    • Outflow obstructions in the urinary tract (e.g., at the pyeloureteral junction or in the terminal ureter).
    • Vesicoureteral reflux (VUR; nonphysiologic reflux of urine from the bladder via the ureters (ureters) into the renal pelvis)
    • Congenital reflux nephropathy; already before birth, a dilation (expansion) of the upper urinary tract is noticeable (boys more often than girls)
  • Distinguish an upper from a lower UTI.
  • Detect late sequelae of the infection (scarring of the renal parenchyma)