Lower UTI

Upper UTI

Complication

Role of imaging:

› Medical conditions

› Surgical conditions (pyonephrosis, renal abscess,

perinephric abscess)

Prefered exam: ultrasound

Role : to find out the underlying pathology

Indication

Suspected of KUB stone

Uncommon infection: TB, fungus

Poor respond to antibiotics

Recurrent infection

Suspected of neurogenic bladder

Suspected of complicated UTI › Due to immunocompromised

host or underlying DM

IVP

› May be normal

› Enlarged kidney

› Displaced calyces

› Delayed nephrogram

US

› Enlarged kidney

› Decreased parenchymal echogenicity

CT Scan

› Enlarged affected

kidney

› Patchy decreased

density on pre-contrast

› Perinephric fat stranding

› Decreased

enhancement

› Urothelial thickening

› Striated nephrogram

A 19-year-old woman with acute left flank pain.

Non-contrast

Post-contrast

Preferred exam: US or CT

Preferred exam: US or CT

Pus produces fluid layers

(dependent echogenic

debris) within the dilated collecting system

Severe necrotizing infection

E. coli is frequent associated causative

organism.

Characterized by gas within renal parenchyma

and occasionally within perirenal tissues.

More than 90% of cases occur in diabetic

patients

Female predominance

Plain film

› Air in renal parenchyma ± entend into perirenal or retroperitoneum space

US › Acoustic shadow from air “ring down or

reverberation” artifact

CT scan › Renal enlargement, impaired renal function,

thickening perirenal fascia

Emphysematous cystitis in a 62-year-old diabetic man

who presented with groin pain and hematuria.

©2004 by Radiological Society of North America

A form of chronic pyelonephritis

› Chronic obstruction plays a part in development.

› Proteus mirabilis is frequent associated causative

organism.

› DM is an associated condition in 10% of cases

Characterized by destruction and replacement of

renal parenchyma by lipid-laden macrophages.

Gross pathologic

› Massive renal enlargement, lithiasis, hydronephrosis

› Perinephric fibrosis and lobulated yellow masses

replacing renal parenchyma.

Diffuse > focal

Plain KUB

› Renal enlargement

› Staghorn calculus

› Extrarenal extension is

suggested by indistinct

outlines of the kidney and

psoas muscle

IVP

› Decreased or absent

excretion in 85% of cases

CT scans › Staghorn calculus with

contracted renal pelvis

› Enlarged kidney and multiple dilated calyces

› Characteristic low-attenuation (10-15 HU), peripherally enhancing rounded masses “bear’s paw sign”

› Extrarenal extension of inflammation thickening of Gerota fascia…

Preferred exam: US

-Decreased

renal size

-Parenchymal scar

-Focal

dilatation of

the calyx opposing the

scar

http://etc.usf.edu/clipart/54200/54271/54271_kidney.htm

IVP

25% associated with pulmonary TB

1. Renal parenchyma infection

2. Ureter and collecting system

TB kidney › Irregular calyx

› Infundibular stenosis

› Calyceal dilatation

› Fibrosis / scarring

› Amputated calyx

› Calcification

moth-eaten calyx

Infundibular stenosis

Amputation of bilateral upper pole calices

TB ureter

› Irregular fibrosis: segmental

dilatation and stenosis of ureter

TB bladder

› Contracted bladder = small bladder capacity

› Calcifed bladder wall