Clinical & Imaging Inputs in Acute Abdominal Inflammatory Conditions

Prof. Raju SharmaAll India Institute of Medical Sciences, New

Delhi

Clinical Inputs

History Pain: location, type,

duration, Fever Vomiting Diarrhoea Distension

Examination Tachycardia Guarding Rigidity Lump

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

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

IMAGING MODALITIES

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

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

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

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

Acute Abdomen

Bowel ObstructionPerforation

Right Upper Quadrant Pain

Biliary pathologyLower Quadrant Pain

Plain Radiographs

CT

USG

Bowel IschemiaGI Bleed

CT Angiography

MRCP/CT DSA/Intervention

USG

CT

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

Complications of Cholelithiasis

Acute cholecystitis Perforation, peri-cholecystic abscess Pancreatitis Gall stone ileus Biliary fistula Mirrizi’s syndrome

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

Acute Cholecystitis

Gangrenous Cholecystitis

Striated thickening of wall, irregularity, intraluminal membrane, Murphy’s sign may be absent

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%

Ruptured GB

Gall stone eroding & causing Pseudoaneurysm

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

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

Liver Abscess

Amoebic Liver Abscess with Typhlitis

Cholangiolar Abscess

Ruptured Liver Hydatid

32yr old: pain, jaundice fever

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

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

Types

Interstitial Pancreatitis (80-90%) Necrotizing Pancreatitis (5-10%)

Necrosis

Pancreatic Peri-pancreatic Combined

Infected Walled off Necrosis

Complications Of Acute Pancreatitis

Pseudocyst Infected walled off necrosis Pseudoaneurysms Vascular thrombosis

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

Splenic Infarction

Causes: pancreatitis, portal hypertension, sickle cell anemia, splenomegaly

Presents with left upper quadrant pain

Peripherally located wedge shaped hypodense, non-enhancing lesion

Splenic Abscess with Rupture

Emphysematous Pyelonephritis

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%

Retrocecal Appendicitis

Perforated Appendicitis

Crohn’s Disease

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

Omental Infarct

Sudden onset of right lower quadrant pain

Fat density with stranding Usually > 5cm Primary/ secondary Usually self limiting Conservative Tt

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

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

Crohn’s Colitis

Ischemic Colitis

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

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

Sub-Phrenic Abscess

Post-Op Patient

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

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

Thank you for your attention!