Clinical and imaging inputs are important for diagnosing acute abdominal inflammatory conditions. A thorough history and physical exam can provide clues to the condition. Key lab tests include a CBC, CRP, and pancreatic enzymes. Imaging plays a crucial role, with ultrasound as a first-line exam and CT being the preferred modality. CT allows evaluation of the entire abdomen and detection of complications. The clinical presentation and location of pain can help determine the appropriate imaging exam and differential diagnoses to consider.

1. Clinical & Imaging Inputs in Acute Abdominal
Inflammatory Conditions
Prof. Raju Sharma
All India Institute of Medical Sciences, New Delhi

2. Clinical Inputs
History
 Pain: location, type, duration,
 Fever
 Vomiting
 Diarrhoea
 Distension
Examination
 Tachycardia
 Guarding
 Rigidity
 Lump

3. Lab Parameters
 CBC
 Leucocytosis with shift to right
 C Reactive Protein: inflammatory marker
 Procalcitonin: biomarker of sepsis
 Pancreatic amylase, lipase: ↑ in acute pancreatitis
 LFTs
 Fecal Calprotectin: marker of bowel inflammation

4. Spectrum
 Acute hepatitis
 Liver abscess
 Acute cholecystitis
 Cholangitis
 Acute pancreatitis
 Acute pyelonephritis
 Acute gynae disease: PID, TO
abscess
 Acute gastroenteritis
 Appendicitis
 Bowel obstruction
 Inflammatory Bowel Disease
 Enterocolitis: Infectious
 Diverticulitis

5. IMAGING MODALITIES
 Plain radiograph (supine/erect)
 Ultrasonography- screening tool
 Computed Tomography- modality of choice
 Magnetic Resonance Imaging – seldom used
 Angiography
 Image guided intervention

6. Computed Tomography
 Modality of choice for abdominal emergencies
 Global perspective of entire abdomen
 Uninhibited by bowel gas & fat
 MDCT: thin collimation, MPRs
 Oral contrast: not useful in emergent situation
 I.V contrast mandatory unless CI
 CT Angiography: bowel ischemia, GI bleed
 Radiation concern: ASIR, low dose protocols

7. Bowel Obstruction
 Small bowel obstruction is more common than large
 Common causes: adhesions, hernia, volvulus, inflammatory strictures,
intussusception, ischemic
 Accounts for 20% of acute abdominal surgical conditions
 Simple/Strangulated
 Complete/Incomplete
 Open/Closed loop

8. Acute Abdomen: Quadrant Approach
 Helps choose modality
 Narrows differential diagnosis
 ACR appropriateness criteria
 RUQ: USG (9) MRI & CT (6)
 LUQ
 RLQ: CT (8) USG (6)
 LLQ: CT (9) USG (4)
 Non-localized pain – CT (8) USG (4)
Beta HCG testing should be done in women of reproductive age group

9. Acute Abdomen
Bowel Obstruction
Perforation
Right Upper Quadrant Pain
Biliary pathology
Lower Quadrant Pain
Plain Radiographs
CT
USG
Bowel Ischemia
GI Bleed
CT Angiography
MRCP/CT DSA/Intervention
USG
CT

10. Right Upper Quadrant Pain
 Among the commonest reasons for ED visit
 USG is the modality of choice, occ CT or MRI are required
 Liver: Ac hepatitis, abscess, hydatid
 Gall Bladder: calculi, ac. cholecystitis & its complications,
Mirrizi syndrome
 Acute pancreatitis
 Peptic ulcer disease

11. Complications of Cholelithiasis
 Acute cholecystitis
 Perforation, peri-cholecystic abscess
 Pancreatitis
 Gall stone ileus
 Biliary fistula
 Mirrizi’s syndrome

12. Acute Cholecystitis
 Commonest cause: gall stones
 Sonography: modality of choice
 Hallmarks: thickened GB wall (>3mm), distended GB,
pericholecystic edema, sonographic Murphy’s sign (92% sensitivity)
 Acalculus cholecystitis – seen in sick ICU patients
 Gangrenous, Emphysematous, Xanthogranulomatous cholecystitis

13. Acute Cholecystitis

14. Gangrenous Cholecystitis
Striated thickening of wall, irregularity, intraluminal membrane, Murphy’s sign may be absent

15. Emphysematous Cholecystitis
• More common in males & diabetics
• Stones seen only in 50%
• Small vessel disease may be
responsible
• Murphy’s sign is often absent
• Organism: Cl. welchii, E coli
• Mortality 15%

16. Ruptured GB

17. Gall stone eroding & causing Pseudoaneurysm

18. Gall Stone Ileus
 Accounts for 1-5% of non-malignant small bowel
obstruction
 GB perforation with fistula formation with
duodenum
 Gall stone impaction occurs in ileum(54-65%),
jejunum (27%) and rarely duodenum (1-3%)
 Bouveret syndrome
 Riggler triad: bowel obstruction, pneumobilia,
obstr. Gall stone – seen in 30-40% patients

19. Mirrizi’s Syndrome
• CHD/ CBD obstruction due to impacted
calculus in GB neck/ cystic duct
• May be associated with cholecystocholedocal
fistula
• Uncommon, 2% of pts operated for
symptomatic gall stones
• Preop diagnosis is important: USG, MRI
• Standard technique of Sx: increased risk of
injury to CBD due to dense adhesions in hepato-
duodenal ligament

20. Liver Abscess

21. Amoebic Liver Abscess with Typhlitis

22. Cholangiolar Abscess

23. Ruptured Liver Hydatid

24. 32yr old: pain, jaundice fever

25. Oriental Cholangiohepatitits (OCH)
• Common in south east Asia
• Rec episodes of RUQ pain, fever,
jaundice
• Multiple intra and extrahepatic
strictures
• Intraductal calculi specially in absence
of gall stones
• Segmental atrophy specially of lateral
segment of left lobe

26. Acute Pancreatitis
 Causes: gall stones, alcohol, abdominal surgery
 CT is the modality of choice
 Balthazar grading system and CT scoring system
 Ideal for detecting pancreatic necrosis
 Can diagnose complications of acute pancreatitis

27. Types
Interstitial Pancreatitis (80-90%) Necrotizing Pancreatitis (5-10%)

28. Necrosis
Pancreatic Peri-pancreatic Combined

30. Infected Walled off Necrosis

31. Complications Of Acute Pancreatitis
 Pseudocyst
 Infected walled off necrosis
 Pseudoaneurysms
 Vascular thrombosis

32. Left Upper Quadrant Pain
 Less common than other sites
 Splenic pathology: infarct, abscess, spontaneous rupture
 Gastritis
 Pancreatitis & its complications
 Left pyelonephritis
 Splenic flexure colitis, ischemia
 Sub-phrenic abscess

33. Splenic Infarction
 Causes: pancreatitis, portal
hypertension, sickle cell anemia,
splenomegaly
 Presents with left upper quadrant pain
 Peripherally located wedge shaped
hypodense, non-enhancing lesion

34. Splenic Abscess with Rupture

35. Emphysematous Pyelonephritis

36. Right Lower Quadrant Pain
 Common presenting symptom
 Ac appendicitis, IC Tb, IBD, amoebic typhlitis, mesenteric adenitis, adnexal
pathology
 Omental infarction, epiploic appendagitis, neutropenic enterocolitis
 Central abdominal pain which shifts to RIF, leucocytosis
 USG followed by CT is the way to go
 Reported sensitivity & specificity of CT for appendicitis: 90-99%

38. Retrocecal Appendicitis Perforated Appendicitis

39. Crohn’s Disease

40. Epiploic Appendagitis
• Oval fat density mass with a
central dot & an inflamed
peripheral hyperdense rim
• D/D: omental infarct which is
usually larger
• Tt: conservative

41. Omental Infarct
 Sudden onset of right lower
quadrant pain
 Fat density with stranding
 Usually > 5cm
 Primary/ secondary
 Usually self limiting
 Conservative Tt

42. Neutropenic Enterocolitis
• Oedema & inflammation of cecum, asc colon
& occ small bowel
• Combination of chemoRx induced mucosal
injury - facilitating infection, altered immune
response
• Should be considered in any neutropenic
patient (<500 cells/cumm) presenting with
fever, pain RIF, GI bleed &/or diarrhoea

43. Left Lower Quadrant Pain
 Causes: colitis, diverticulitis, urolithiasis, epiploic appendagitis, gynae causes
 CT is considered the modality of choice
 Colitis: ischemic, infective, pseudomembranous, UC, Crohn’s
 An empty colon sign favours infective colitis over ischemic & inflammatory
etiology
 Crohn’s & pseudomembranous colitis: greater wall thickening than in
ischemic & UC
 Adnexal pathology

44. Crohn’s Colitis

45. Ischemic Colitis

46. Diverticulitis
• Bowel wall thickening, peri-colonic
inflammation, diverticulosis
• Inflamed diverticuli may be
hyperdense on CT
• Sigmoid colon: most often involved
• Hinchey’s classification
• Perforated malignancy may mimic
perforated diverticulitis

48. Intra-Abdominal Abscess
 Post-operative patient
 Complication of appendicitis, bowel perforation
 Inflammatory Bowel Disease
 Diverticulitis
 On USG: fluid with debris
 Fluid attenuating lesion with thick rim enhancement
 On MRI: fluid signal with restricted diffusion

49. Sub-Phrenic Abscess

50. Post-Op Patient

51. Acute Abdomen in Pregnancy &
Women in Reproductive Age Group
 As far as possible avoid ionizing radiation
 Sonography first line
 MRI (no Gadolinium) is very useful
 CT only if benefit outweighs the risk
 Non-pregnancy related: biliary, acute appendicitis
 Pregnancy related: ectopic, abruption, HELLP
 Gynae causes: PID, TO abscess, ovarian hgic cyst, torsion

52. Conclusion
 Wide spectrum of diseases
 Clinical findings: often non-specific & frequently overlap
 Judicious use of imaging modalities: narrow D/d & triage patients
 Diagnostic laparotomy: thing of the past
 USG & CT: mainstay of imaging
 Niche indications for MRI
 Quality of imaging & interpretation must be high

53. Thank you for your attention!