CT plays an important role in imaging urosepsis and urinary tract infections. It can confirm or change diagnoses in 33-59% of cases and change treatment in 28-42% of cases. CT is useful for detecting infection foci when clinical infection is obscure. It can identify various urinary tract conditions like pyelonephritis, renal and perinephric abscesses, xanthogranulomatous pyelonephritis, and tuberculosis. Findings include renal enlargement, parenchymal defects, nephromegaly, perinephric stranding, and calcifications. CT accurately depicts the extent of infection and guides appropriate management.

1. Role of CT in
imaging of urosepsis
DR/AHMED BAHNASSY
CONSULTANT RADIOLOGIST
ALEXANDRIA UROLOGY HOSPITAL
Alexandria Urology
Hospital AUH

2. Severity patterns of urosepsis
(a) Asymptomatic
(b) Causing local symptoms such as dysuria, urinary
frequency, urgency, supra- or retropubic
pain or bladder tenderness
(c) Causing general symptoms including fever,
flank pain, nausea and vomiting.
(d) Systemic inflammatory response syndrome
with fever or hypothermia, hyperleucocytosis
or leucopenia, tachycardia and tachypnoea
(e) Circulatory and organ failure

3. Eur Radiol. 2017 Nov;27(11):4544-4551. doi: 10.1007/s00330-017-4897-6. Epub 2017 Jun 12.
Impact of multidetector computed tomography on the diagnosis and treatment of patients with
inflammatory response syndrome or sepsis.
Schleder S1, Luerken L2, Dendl LM2, Redel A3, Selgrad M4, Renner P5, Stroszczynski C2, Schreyer AG2.
OBJECTIVES:
To evaluate the impact of CT scans on diagnosis or
change of therapy in patients with systemic
inflammatory response syndrome (SIRS) or sepsis and
obscure clinical infection.
METHODS:
CT records of patients with obscure clinical infection
and SIRS or sepsis were retrospectively evaluated.
Both confirmation of and changes in the diagnosis or
therapy based on CT findings were analysed by means
of the hospital information system and radiological
information system. A sub-group analysis included
differences with regard to anatomical region, medical
history and referring department.
.
RESULTS:
Of 525 consecutive patients evaluated, 59% had been
referred from internal medicine and 41% from surgery. CT
examination had confirmed the suspected diagnosis in
26% and had resulted in a different diagnosis in 33% and
a change of therapy in 32%. Abdominal scans yielded a
significantly higher (p=0.013) change of therapy rate
(42%) than thoracic scans (22%). Therapy was changed
significantly more often (p=0.016) in surgical patients
(38%) than in patients referred from internal medicine
(28%).
CONCLUSIONS:
CT examination for detecting an unknown infection focus
in patients with SIRS or sepsis is highly beneficial and
should be conducted in patients with obscure clinical
infection.

5. The logic of imaging
Gravity of clinical condition may not
correspond to radiological findings.
The benefit of use of contrast medium is
far more than any risk.
Ultrasound is the initial examination and
can be the only available
tool(pregnancy)

6. 1.Acute Pyelitis
Bilateral pyelitis:
Even thickening and contrast uptake in the walls of the
renal pelvis .
The presence of cortical defects is visible and this
corresponds to the sequelae of pyelonephritis

7. 2.Acute pyelonephritis
 Acute pyelonephritis (APN) is an extensively described,
well-known disease. The first descriptions date to
ancient Egypt, underlining its severity and its potential
to lead to sepsis, kidney abscesses and destruction of
the kidney parenchyma
the Ebers Papyrns from
ancient Egypt recommended
herbal treatment to
ameliorate urinary symptoms
without providing insight into
pathological
mechanisms.

8. Acute Pyelonephritis
 Spoked wheel appearance.
 Striated nephrogram.
 Nephromegaly.
 Perinephric stranding.
Fat is the mirror of the
abdomen.

9. 3.Chronic pyelonephritis
Chronic pyelonephritis: a: axial view; b: coronal
reconstruction. Pyelonephritis scar tissue combining
cortical retraction and deformation of the calyces with
areas in between that are comparatively healthy seen on
contrast-enhanced CT scan.
Fat stranding key of concurrent
inflammation

10. 4.Focal bacterial nephritis
AFBN of the left kidney.
Pseudotumoural left kidney mass, made up of tissue
combined with multiple hypodense microabscesses:

11. 5.Renal abscess
Renal abscess: a: axial view; b: coronal view. Fluid-filled
collection in the left kidney, with septations and thick walls

12. 6.Emphysematous pyelonephritis
 Emphysematous pyelonephritis refers to a morbid infection with
particular gas formation within or around the kidneys.
 If not treated early, it may lead to fulminant sepsis and, therefore, carries a
high mortality.
 It tends to be more common in females, and approximately 90% of
patients have uncontrolled diabetes mellitus . It may however also be seen
in immunocompromised individuals or associated with urolithiasis ,
neoplasms, or sloughing of papilla.
 Causative organisms include:
 E. Coli: usually considered the commonest causative organism 3
 Klebsiella pneumonia
 Proteus mirabilis

13. Types
 type 1
 greater than one-third renal parenchymal destruction
 streaky or mottled appearance of gas
 intra- or extrarenal fluid collections are characteristically absent
 it is usually more aggressive and lead to death shortly, if not intervened early
 mortality 70%
 type 2
 destruction of less than one-third of the parenchyma
 renal or extrarenal collections associated with bubbly or loculated gas, or gas within
pelvicalyceal system or ureter
 mortality 20%

14. Huang-Tseng CT classification system
 class 1: gas in the collecting system only
 class 2: gas in renal parenchyma only (without extrarenal extension)
 class 3: gas in renal parenchyma with extrarenal extension
 class 3a: extension of gas or abscess to perinephric space
 class 3b: extension of gas or abscess to pararenal space
 class 4: bilateral emphysematous pyelonephritis or solitary kidney with
emphysematous pyelonephritis

15. Emphysematous pyelonephritis
Early emphysematous pyelonephritis. Intraparenchymal
gas bubbles found on CT .

16. 63-year-old male admitted to emergency
department because of high fever, dysuria and
distended tender abdomen was diagnosed with
decompensated diabetes mellitus, severe renal
impairment , markedly increased C-reactive protein
andmetabolic acidosis. Initial ultrasound showed
enlargement of the right kidney, with parenchymal
hyperechoic bands , posterior acoustic shadowing and
previously unknown congenital left renal aplasia
CT confirmed enlarged solitary right kidney
with strongly hypoattenuating gaseous components,
consistent ith emphysematous pyelonephritis.

17. 7.Xanthogranulomatous
pyelonephritis (XGP)
 Xanthogranulomatous pyelonephritis (XGP) is a rare form of chronic
pyelonephritis and represents a chronic granulomatous disease resulting in a
non-functioning kidney.
 Clinical presentation is typically vague, consisting of constitutional symptoms
such as malaise, weight loss and low-grade fever. Hematuria and flank pain
are sometimes encountered
 Despite often absent urinary tract symptoms, pyuria and positive urinary
cultures are present in the majority of cases (95 and 60% respectively) 2.
 result of subacute/chronic infection inciting a chronic but incomplete immune
reaction . Various bacteria are isolated, however, the most commonly isolated
species are Escherichia coli and Proteus mirabilis 1,4.
 The kidney is eventually replaced by a mass of reactive tissue, surrounding
the usually present (90%) inciting staghorn calculus with
associated hydronephrosis of a greater or lesser degree. Foamy (lipid-laden)
macrophages predominate .

18. Stages and types
 Staging
 One method of staging is based on the degree of involvement of the adjacent tissues :
 stage I: the disease is confined to the renal parenchyma only
 stage II: involves renal parenchyma as well as an extension to perirenal fat
 stage III: disease extends into the perirenal and pararenal spaces or diffuse retroperitoneum
Types
 Two forms of the disease are recognized both macroscopically and on imaging 1,5:
 diffuse (90%)
 focal (10%)
 sometimes a truly focal process in a normal kidney
 in other instances, this represents diffuse XGP of one moiety of a duplex system

19. Xanthogranulomatous pyelonephritis
The combination of characteristic CT
features,
(a) Non-functioning kidney
(b) Central lithiasis
(c) Calyceal dilatation
(d) Perinephric involvement

20. XGP
Long
standing
lithiasis

21. Extension of infection
Peri/para
renal
involvement

22. Extension of infection
Muscles and
abscess
formation

23. A 64-year-old female presented to emergency
department with low-grade fever and painful
erythematous swelling in her right lumbar region, without
any previous surgical or interventional procedures.
CT showed right kidney with reduced, poorly functioning
parenchyma, calcific pelvicalyceal stones. A fluid-
containing track with enhancing walls consistent
with spontaneous fistulisation was seen crossing through
the perinephric, posterior pararenal spaces and
abdominal wall muscles, to form a large abscess..

24. 8.Cyst infection
Enhanced
wall

25. 9.Pyonephrosis
Pyonephrosis represents
an infected, obstructed and frequently
enlarged, collecting system

27. seminal vesicles

28. Prostate abscess
Massively enlarged prostate with marked surrounding
inflammation and central liquifaction indicative of abscess.

29. Epididymo-orchitis-scrotal abscess
Scrotal wall cellulitis is more frequent in obese, diabetic
or immunocompromised patients; however
scrotal wall abscess may occur also in young men
due to infected hair follicles and infections of
scrotal lacerations.
Scrotal wall abscess may be
the evolution of untreated scrotal cellulitis.

30. Fournier gangrene
Fournier’s gangrene (FG) is a polymicrobial
necrotising fasciitis that involves the perineal,
perianal or genital regions and constitutes a urologic
emergency with a potentially high mortality

31. Role of CT
Fournier’s gangrene in a
63-year-old diabetic male with recurrent UTIs and perineal
painful swelling.

32. Perineal infections Extensive cryptogenetic perianal inflammation
in a 56-year old diabetic male with fever.
CT image revealed perineal abscess
Additional MRI including axial STIR , post-gadolinium
axial fat-suppressed and coronal T1-weighted
images showed extensive inflammatory signal
abnormalities and hyperenhancement (+) surrounding the
anus,and extending to the ischioanal fossa.
Topography of infection, sparing of prostate and corpora
cavernosa and clinical examination were inconsistent
with complicated UTI

34. Galaxy of findings
1. Chronicicty
2. Spread
3. Different ages.
4. Distortion.
5. Vague symptoms

35. Early
The earliest CT renal features of UG-TB reflect
localized tissue oedema from active inflammation
and include focal hypoperfused parenchymal
areas and sometimes small-sized cortical abscess-like
collections; therefore, the appearance closely
mimics that of bacterial acute pyelonephritis.
Occasionally, tuberculosis may masquerade as
a solid renal mass with minimal enhancement

36. Lobar caseation

37. Late
Late renal changes consistent with advanced
disease include a multiloculated cystic appearance
from progression and confluence of caliectasis,
and presence of calcifications
Contracted nodular kidney

38. The mild urothelial thickening along the right renal pelvis
and ureter showed positive contrast enhancement
The atrophied right kidney had uneven calyceal
dilatation

39. Nephrographic acquisition :left upper renal pole
thinned parenchyma and dilated and distorted calyces
opacified by urine in the delayed excretory phase.
An additional focal renal scarring with calcification was
Noted .
Findings were consistent with chronic
tubercular infection.

40. References
Massimo Tonolini:Imaging and Intervention in Urinary Tract Infections and
Urosepsis.
Tuberculosis of the genitourinary system-Urinary tract tuberculosis: Renal
tuberculosis ;Suleman Merchant, Alpa Bharati, Neesha Merchant1
Department of Radiology, LTM Medical College and LTM General Hospital,
Mumbai, India, 1Department of Radiology,University Health Network, University of
Toronto, Toronto, Canada.
Eur Radiol. 2017 Nov;27(11):4544-4551. doi: 10.1007/s00330-017-4897-6. Epub
2017 Jun 12.
Impact of multidetector computed tomography on the diagnosis and treatment of
patients with systemic inflammatory response syndrome or sepsis.
Schleder S1, Luerken L2, Dendl LM2, Redel A3, Selgrad M4, Renner
P5, Stroszczynski C2, Schreyer AG2.