Dr. Brian Shreve is an Emergency Medicine Resident and Dr. Isolina Rossi is a Surgery Resident at Carolinas Medical Center in Charlotte, NC. They are interested in medical education. With the guidance of Drs. Kyle Cunningham and Michael Gibbs, they aim to help augment our understanding of emergent abdominal imaging. Follow along with the EMGuideWire.com team as they post these monthly educational, self-guided radiology slides on: • Staghorn Caculi • Xanthogranulomatous Pyelonephritis • Fecal Impaction • Horseshoe Kidney • Polycystic Kidney Disease • Blunt Renal Trauma

1. Adult Abdominal Imaging Case Studies
Isolina R. Rossi, MD & Brian P. Shreve, MD
Department of Surgery & Emergency Medicine
Carolinas Medical Center & Levine Children’s Hospital
Kyle Cunningham, MD & Michael Gibbs, MD - Faculty Editors
Abdominal Imaging Mastery Project
April 2020

2. Disclosures
▪ This ongoing abdominal imaging interpretation series is proudly co-
sponsored by the Emergency Medicine & Surgery Residency Programs at
Carolinas Medical Center.
▪ The goal is to promote widespread interpretation mastery.
▪ There is no personal health information [PHI] within, and ages have been
changed to protect patient confidentiality.

3. Process
▪ Many are providing cases and these slides are shared with all contributors.
▪ Contributors from many Carolinas Medical Center departments, and now…
Brazil, Chile and Tanzania.
▪ Cases submitted this month will be distributed next month.
▪ When reviewing the presentation, the 1st slide will show an image without
identifiers and the 2nd slide will reveal the diagnosis.

4. It’s All About The Anatomy!

5. Systematic Approach to Abdominal CTs
● Aorta Down - follow the flow of blood!
○ Thoracic Aorta → Abdominal Aorta → Bifurcation → Iliac a.
● Veins Up - again, follow the flow!
○ Femoral v. → IVC → Right Atrium
● Solid Organs Down
○ Heart → Spleen → Pancreas → Liver → Gallbladder → Adrenal →
Kidney/Ureters → Bladder
● Rectum Up
○ Rectum → Sigmoid → Transverse → Cecum → Appendix
● Esophagus down
○ Esophagus → Stomach → Small bowel

6. Systematic Approach to Abdominal CTs
● Abdominal Wall/Soft tissue Up
○ Free air, abscesses, hernias
● Retroperitoneum Down
○ Hematoma, masses
● GU Up
○ Masses
● Tissue specific windows
○ Lung
○ Bone
● Don’t forget to look at multiple planes
○ Axial, sagittal, coronal

7. 28-year-old female presents
with right flank pain, hematuria,
and dysuria for 3 weeks.
Diagnosis?

8. 28-year-old female presents
with right flank pain, hematuria,
and dysuria for 3 weeks.
Here are the CT images of the
same patient.
Diagnosis?

9. 28-year-old female presents
with right flank pain, hematuria,
and dysuria for 3 weeks.
Diagnosis?
Staghorn Calculi: Urine culture
positive for Klebsiella.
Percutaneous nephrostomy
tube was placed and the patient
was discharged with plan for
outpatient follow-up.

10. 28-year-old female returns to
ED with continued pain 1 month
after percutaneous
nephrostomy tube placement.
Diagnosis?

11. 28-year-old female returns to
ED with continued pain 1 month
after percutaneous
nephrostomy tube placement.
Diagnosis?

12. 28-year-old female returns to
ED with continued pain 1 month
after percutaneous
nephrostomy placement.
Diagnosis?
Xanthogranulomatous
Pyelonephritis.
Notice the change in the renal
parenchyma and worsening
hydronephrosis as compared
with the first visit despite the
nephrostomy tube.
The patient ultimately required
a right nephrectomy.
First Visit Second Visit

14. ● A rare parenchymal destructive process after chronic urinary
tract obstruction or infection
● All patients were symptomatic
● All patients had renal calculi
○ 34.1% were staghorn calculi
● 85% of patients with XGP were women
● Urine culture results
○ 35.3%- E. Coli
○ 17.6%- Proteus mirabilis
○ 35%- Sterile
● CT findings: hydronephrosis, kidney enlargement, poor
excretion of contrast, dilated calyces
○ Spread of the disease beyond the kidney (22.0%)
and to the psoas muscle (17.1%)
● Most patients had an open nephrectomy, higher
complication rate with initial laparoscopic approach

16. Renal enlargement 100%
Multiple dilated calyces and abnormal parenchyma 82%
Calculus with obstruction 55%
Focal fat deposits* 27%
Renal abscess 18%
Extra-renal inflammatory changes 91%
Abscesses of abdominal and bowel walls 27%
Splenic abscess 9%
*Pathologic finding of XGP
CT Imaging Findings In A Limited Case Series Of 11 Patients With XGP

17. 78-year-old female presents
from a nursing facility
unresponsive, with a GCS= 3
and hypoxia.
Diagnosis?

18. 78-year-old female
presents from a nursing
facility unresponsive,
with a GCS= 3 and
hypoxia.
CT Abdomen & Pelvis.
Diagnosis?

19. 78-year-old female
presents from a nursing
facility unresponsive,
with a GCS= 3 and
hypoxia.
What do you notice
about the kidneys?
Diagnosis?

20. Fecal impaction
Hydronephrosis
Horseshoe Kidney
78-year-old female presents
from a nursing facility
unresponsive, with a GCS= 3
and hypoxia.
What do you notice about the
kidneys?
Fecal Impaction + Horseshoe
Kidneys With Bilateral
Hydronephrosis.

22. Horseshoe Kidney (HSK)- Epidemiology
• HSK is the most common congenital fusion abnormality of the urinary tract
• 3 anatomic abnormalities:
• Ectopia
• Malrotation
• Vascular changes
• 1 in 400-600 individuals
• Men to women (2:1)
• Present in 20% of patients with Trisomy 21
• Present in 60% of patients with Turner Syndrome
• Increased risk of malignancy
• Typically renal cell carcinoma
• Transitional cell carcinoma- secondary to chronic infections, stones, UPJ obstruction
• Wilms tumor in childhood

23. Horseshoe Kidney (HSK)- Anatomy
• Trapped under the IMA when ascending from the pelvis
• Traps kidneys in the lower lumbar region, although it can appear at anywhere along the
ascent from the pelvis
• Usually located at the 3 or 5th lumbar spine
• Under IMA anterior to AA and IVC
• Typically connected at lower poles
• Rarely “inverted” and connected at upper poles
• UPJ higher than normal at superior part of each kidney
• Higher rates of compression
• Compressed against the lumbar spine and not protected by ribs
• Increased serious injuries following trauma

24. Horseshoe Kidney (HSK)- Vascular
Abnormalities
Arterial Venous

25. Horseshoe Kidney (HSK)-
Presentation/Management
• Typically asymptomatic and found incidentally
• If symptomatic, typically secondary to UPJ obstruction;
• Hydronephrosis
• Lithiasis (16-60%)- higher proportion of staghorn calculi
• Pyelonephritis
• Pain is generally in the low lumbar area compared to more traditional flank
pain.
• Can now be detected as early as the first trimester prenatally with ultrasound
• Standard urologic management for UPJ obstruction is typically all that is
needed

26. 66-year-old female an MRI for
routine disease monitoring.
Diagnosis?

27. 66-year-old female an MRI for
routine disease monitoring.
Axial images of kidneys & liver.
Diagnosis?

28. 66-year-old female an MRI for
routine disease monitoring.
Axial images of kidneys & liver.
Diagnosis?
Polycystic kidney & liver disease.

30. Autosomal Dominant Polycystic Kidney
Disease
• ADPKD most common hereditary kidney disorder
• PKD1 (78%), PKD2 (15%), with hundreds of other associated mutations
• Prevalence: 1 in 1000-2500
• ESRD by 6th decade of life
• Complications:
• Chronic pain
• Gross hematuria
• Cyst infection
• Nephrolithiasis
• Abdominal hernias
• Typical complications of of ESRD

31. Diagnosis
● Ultrasound
○ Low cost, non-invasive
○ ID cysts as small as 2-
3mm
● MRI next best option
○ 10 cysts with specificity
and sensitivity of 100% in
at risk under 40 years old
○ Less than 5 cysts excludes
the disease
● If no family history cannot rule
out with imaging alone

32. ADPKD Extrarenal Manifestations
• Polycystic Liver disease
• 90% of patients older than 35, 20% symptomatic
• Worse in females, estrogen exposure, multiple pregnancies
• Normal synthetic function
• Intracranial aneurysms
• 4x higher than general population 9-12%
• If family history- 22%, no family history 6%
• Screen with MRA if positive family history, ruptured aneurysm, high risk
occupations
• Cysts in other locations
• Pancreas, seminar vesicles, ovaries, and cardiac disease
• Rarely symptomatic, no need for routine screening

33. ADPKD Treatment
Non-Operative
• Drinking large amounts of
water (inhibits vasopressin
activity, prevents
nepthrolithiasis)
• Statin therapy
• Antiproliferative agents- still
in development, all studies
negative to date
• Somatostatin analogues
Operative
• Nephrectomy (high morbidity
and mortality w/o transplant)
• Transplant
• Embolization
• Cyst fenestration
• Cyst aspiration
• Foam sclerotherapy

34. 41-year-old female presents
following MVC. Complaining of
flank pain and hematuria,
otherwise no concerning
physical exam findings.
Diagnosis?

35. Renal laceration
through the collecting
system.
Perinephric
fluid collection.
41-year-old female presents
following MVC.
Left renal laceration with
perinephric fluid collection.
Note that there is no
active extravasation of
contrast.

36. AAST Kidney Injury
Grading Scale
• This patient has a AAST grade IV
injury: parenchymal laceration
extending into the collecting
system.
• Radiopaedia.com provides
images of different grades of
injury:
https://radiopaedia.org/articles/aast-kidney-injury-
scale?lang=us#image_list_item_6539445

37. AUA renal injury management guidelines
• Clinicians may initially observe patients with renal parenchymal
injury and urinary extravasation.
• Clinicians should perform follow-up CT imaging for renal
trauma patients having either:
• (a) deep lacerations (AAST Grade IV-V)
• (b) clinical signs of complications (e.g., fever, worsening flank pain,
ongoing blood loss, abdominal distention).
• Clinicians should perform urinary drainage in the presence of
complications such as enlarging urinoma, fever, increasing pain,
ileus, fistula or infection.
https://www.auanet.org/guidelines/urotrauma-guideline

38. Summary Of Diagnoses This Month
● Staghorn Calculi/ Xanthogranulomatous
Pyelonephritis
● Fecal impaction/Horseshoe Kidney
● Polycystic Kidney Disease
● Blunt renal trauma

39. See You Next Month!