• Sleisenger & Fordtran's GI and Liver Disease (appendicitis with Alvarado score, biliary disease)
• Sabiston Textbook of Surgery (LUTS/BPH management, TURP)
• Pye's Surgical Handicraft (UC, intestinal obstruction)
• Bailey & Love's Short Practice of Surgery (appendicitis, general surgery)Here are the complete, detailed answers for all questions from your MS General Surgery examination paper:

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MS General Surgery Examination - January 2025

Model Answers from Standard Surgical Textbooks

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Q.1 (30 marks) - Gallbladder Stones: Etiology, Clinical Presentations, Investigations & Tenets of Safe Cholecystectomy

A. ETIOLOGY OF GALLBLADDER STONES

1. Cholesterol Stones (80% in Western countries)

• Supersaturation of bile with cholesterol - the liver secretes too much cholesterol relative to bile salts ("lithogenic bile")
• Accelerated nucleation - cholesterol monohydrate crystals precipitate from supersaturated bile faster than normal, promoted by mucin glycoproteins and other pronucleating factors
• Gallbladder hypomotility - impaired emptying allows nucleated crystals to aggregate into stones

• Fat (obesity - BMI >30 triples the risk)
• Female (estrogen increases cholesterol secretion; progesterone reduces gallbladder motility)
• Fertile (multiparity)
• Forty (increasing age - prevalence rises with age)
• Fair (Caucasian/Native American populations)
• Family history (genetic predisposition)

2. Pigment Stones

• Black pigment stones: Calcium bilirubinate + calcium carbonate/phosphate. Formed in the gallbladder in conditions of excess unconjugated bilirubin - hemolytic anemias (sickle cell, hereditary spherocytosis, thalassemia), cirrhosis, ileal disease. Biliary infection is NOT required.
• Brown pigment stones: Calcium bilirubinate + calcium palmitate + cholesterol. Form in bile ducts due to biliary infection (E. coli producing beta-glucuronidase that deconjugates bilirubin) and biliary stasis/parasites (Clonorchis sinensis, Ascaris). Common in Asia.

3. Mixed Stones

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B. CLINICAL PRESENTATIONS

1. Asymptomatic (Silent) Gallstones (~70-80%)

2. Biliary Colic (Symptomatic, Uncomplicated)

• Pathophysiology: Transient impaction of a stone in the cystic duct or Hartmann's pouch
• Pain: Steady, severe RUQ or epigastric pain (misnomer - NOT colicky), radiating to the right scapula/shoulder tip (due to diaphragmatic irritation via phrenic nerve)
• Duration: 30 minutes to 6 hours; resolves when stone dislodges
• Precipitants: Fatty meals (stimulate CCK release and gallbladder contraction)
• Associated symptoms: Nausea, vomiting, flatulence, fatty food intolerance
• No fever, no jaundice in uncomplicated colic

3. Acute Cholecystitis

• Pathophysiology: Persistent cystic duct obstruction causing chemical inflammation of gallbladder wall, secondary bacterial infection (E. coli, Klebsiella, Enterococcus)
• Pain: Persistent RUQ pain (>6 hours), worse on inspiration
• Murphy's sign positive: Inspiratory arrest on palpation of RUQ (gallbladder compressed against examining fingers)
• Sonographic Murphy's sign on USS
• Systemic signs: Fever (38-38.5°C), leukocytosis
• Complications: Empyema (pus-filled gallbladder), gangrene, perforation, pericholecystic abscess
• Tokyo Guidelines TG18 criteria for diagnosis (local + systemic + imaging findings)

4. Choledocholithiasis (CBD stones)

• Presentation: RUQ pain + jaundice (obstructive) + elevated serum bilirubin, ALP, GGT
• Charcot's Triad: RUQ pain + fever with rigors + jaundice = ascending cholangitis (life-threatening emergency)
• Reynolds' Pentad: Charcot's triad + shock + altered mental status = suppurative cholangitis
• Requires urgent ERCP + sphincterotomy + stone extraction

5. Gallstone Pancreatitis

• Stone impacted at ampulla of Vater
• Epigastric pain radiating to back, raised serum amylase/lipase (>3x normal)

6. Gallstone Ileus

• Rare; large stone (>2.5 cm) erodes through gallbladder into duodenum (cholecystoduodenal fistula), travels to terminal ileum causing mechanical small bowel obstruction
• Rigler's triad on X-ray: small bowel obstruction + pneumobilia + ectopic gallstone

7. Mucocele / Empyema

• Hydrops: cystic duct obstruction without infection - distended gallbladder filled with mucus
• Empyema: infection superimposed - patient toxic with high fever

8. Carcinoma of Gallbladder

• Porcelain gallbladder and large stones (>3 cm) are associated with increased risk

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C. INVESTIGATIONS

Blood Tests

Imaging

1. Ultrasound (USS) - Investigation of Choice:
   • Detects gallstones with sensitivity >95%
   • Shows acoustic shadowing behind stones
   • Gallbladder wall thickening (>3-4 mm) in acute cholecystitis
   • Pericholecystic fluid, positive sonographic Murphy's sign
   • Dilated CBD (>6 mm = suggestive; >8 mm = significant)
   • Limitations: poor visualization of CBD stones (sensitivity ~50%)
2. Plain X-ray Abdomen:
   • Only 10-15% of gallstones are radio-opaque (calcium-containing)
   • Pneumobilia (air in biliary tree) suggests fistula or post-sphincterotomy
   • Rigler's triad in gallstone ileus
3. MRCP (Magnetic Resonance Cholangiopancreatography):
   • Non-invasive, no radiation
   • Gold standard for CBD stone visualization (sensitivity 90-95%)
   • Shows entire biliary tree
4. ERCP (Endoscopic Retrograde Cholangiopancreatography):
   • Both diagnostic AND therapeutic
   • Sphincterotomy + stone extraction for CBD stones
   • Bile sampling for cytology/culture
5. HIDA Scan (Hepatobiliary Iminodiacetic Acid Scintigraphy):
   • Non-visualization of gallbladder confirms cystic duct obstruction
   • Used when USS equivocal in suspected acute cholecystitis
6. CT Scan Abdomen:
   • Detects complications (perforation, abscess, pneumobilia, gallstone ileus)
   • CT cholangiography for biliary anatomy
7. Endoscopic Ultrasound (EUS):
   • High sensitivity for small CBD stones and microlithiasis
   • Used before ERCP to avoid unnecessary intervention

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D. TENETS OF SAFE CHOLECYSTECTOMY

1. Critical View of Safety (CVS) - Strasberg's Criteria

• The hepatocystic triangle must be dissected free of fat and fibrous tissue
• Two and only two structures (cystic duct and cystic artery) should be seen entering the gallbladder
• The lower third of the gallbladder should be separated from the liver bed
• CVS must be achieved before ANY structure is clipped or divided

2. The "Infundibulum-First" or Fundus-Down Technique

• Dome-down/retrograde cholecystectomy when inflammation prevents identification of CVS
• Start at fundus, dissect toward Calot's triangle

3. Identification of Calot's Triangle Contents

• Boundaries: Cystic duct (below), common hepatic duct (medially), inferior border of liver (above)
• Identify cystic duct-CBD junction clearly before any clipping
• The cystic duct is usually shorter and narrower than the CBD
• Do NOT clip any structure until confident of identification ("if in doubt, don't cut")

4. Intraoperative Cholangiogram (IOC)

• Confirm biliary anatomy before division
• Detect unexpected CBD stones
• Mandatory when anatomy is unclear or variation suspected

5. Avoid Excessive Traction

• Tenting the CBD - tent sign - occurs when cystic duct is pulled, making CBD appear to be the cystic duct
• Use gentle lateral and caudal traction on Hartmann's pouch

6. Conversion to Open Surgery

• Never hesitate to convert when:
  • Anatomy is unclear
  • Dense adhesions/inflammation prevent safe dissection
  • Uncontrolled bleeding
  • Bile duct injury suspected
  • Conversion is a sign of surgical judgment, not failure

7. Appropriate Patient Positioning and Port Placement

• 30° reverse Trendelenburg + left lateral tilt to displace bowel
• 4-port technique with adequate triangulation

8. Drain Placement

• Not routinely required
• Use drain when bile leak is suspected or hemostasis not perfect

9. Timing

• Acute cholecystitis: Early cholecystectomy within 48-72 hours of presentation is preferred (Tokyo Guidelines)
• Reduces total hospital stay and avoids risk of interval complications

10. Post-operative Check

• Ensure no bleeding from cystic artery stump
• Inspect gallbladder fossa for bile leak (bilious fluid confirms leak)

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Q.2 (30 marks) - Assessment of Patients with LUTS & Management of BPH

A. ASSESSMENT OF PATIENTS WITH LOWER URINARY TRACT SYMPTOMS (LUTS)

LUTS Classification

1. History

• Symptom characterization: Duration, severity, voiding vs. storage, impact on quality of life
• International Prostate Symptom Score (IPSS): Validated 7-item questionnaire (0-35 points): mild 0-7, moderate 8-19, severe 20-35 + quality of life (QoL) question
• Voiding diary: Records fluid intake, frequency, volumes voided, episodes of urgency/incontinence over 3 days
• Hematuria: Must be investigated - carcinoma in situ, transitional cell carcinoma
• UTI symptoms: Dysuria, fever, cloudy urine
• Sexual function: Erectile dysfunction, ejaculatory dysfunction (relevant to treatment choice)
• Medications: Diuretics, anticholinergics, alpha-agonists (worsen voiding), alpha-blockers
• Medical history: DM (neurogenic bladder), neurological disease (Parkinson's, MS, stroke), previous urethral/pelvic surgery

2. Physical Examination

• Digital Rectal Examination (DRE):
  • Prostate size estimation (normal ~20 g, BPH >30 g)
  • Consistency: BPH - uniformly firm, rubbery, smooth, normal sulcus
  • Suspicious features: hard nodule, irregular surface, loss of sulcus = carcinoma until proven otherwise
  • Rectal tone assessment
• Abdominal examination: Palpable/percussable bladder (chronic retention)
• Neurological examination: Perineal sensation, anal tone (sacral roots S2-S4), lower limb reflexes
• External genitalia: Meatal stenosis, phimosis, urethral discharge

3. Investigations

Baseline (Mandatory)

• Urinalysis + Urine culture: Exclude infection, hematuria, glycosuria
• Serum creatinine/eGFR: Assess renal function (bilateral hydronephrosis from chronic retention)
• PSA (Prostate-Specific Antigen): After counseling; elevated in BPH, prostatitis, carcinoma; age-adjusted normals used; free:total PSA ratio helps differentiate BPH (>25%) from cancer (<15%)

Urodynamic Studies

• Uroflowmetry: Non-invasive, objective measure of voiding
  • Normal peak flow (Qmax) >15 mL/sec
  • BPH typically shows Qmax <10 mL/sec with prolonged voiding time and reduced average flow
  • Plateau pattern on flow curve
• Post-Void Residual (PVR): Measured by USS or catheter post-void
  • Normal <50 mL; >200 mL significant; indicates incomplete bladder emptying and increased infection risk
• Pressure-Flow Studies (Urodynamics): Invasive; distinguishes detrusor underactivity from BOO; reserved for complex cases before surgical intervention

Imaging

• Renal and Bladder USS: Assess upper tract dilation (hydronephrosis from chronic retention), bladder wall trabeculation/diverticula, measure PVR, estimate prostate volume
• Transrectal USS (TRUS): Accurate prostate volume measurement (for treatment planning); guide TRUS biopsy if PSA elevated
• CT Urogram/IVU: If hematuria present to exclude upper tract transitional cell carcinoma

Endoscopy

• Cystoscopy: Indicated if hematuria, suspected stricture, bladder tumor, or before surgical intervention; assesses bladder neck, degree of prostatic lobe protrusion, bladder wall changes (trabeculation, diverticula)

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B. MANAGEMENT OF BENIGN PROSTATIC HYPERPLASIA (BPH)

Pathophysiology

• Static component: Mechanical obstruction by enlarged gland
• Dynamic component: Increased smooth muscle tone in prostate/bladder neck (mediated by alpha-1 adrenoreceptors)

1. Watchful Waiting (Active Surveillance)

• For mild LUTS (IPSS 0-7) or moderate symptoms not bothersome to patient
• Lifestyle modifications: fluid restriction (especially before bed/going out), reduce caffeine/alcohol, double voiding, pelvic floor exercises, treat constipation
• Annual reassessment with IPSS, uroflowmetry, PVR

2. Medical Management

Alpha-1 Adrenoreceptor Blockers (Alpha-Blockers)

• Mechanism: Block alpha-1A receptors in prostate smooth muscle and bladder neck - reduce dynamic obstruction
• Drugs: Tamsulosin (0.4 mg OD - most uroselective), Alfuzosin, Doxazosin, Terazosin
• Onset: Within 1-2 weeks
• Side effects: Postural hypotension (less with tamsulosin), retrograde ejaculation, dizziness
• First-line for moderate LUTS

5-Alpha Reductase Inhibitors (5-ARIs)

• Mechanism: Block conversion of testosterone to DHT (dihydrotestosterone - the active androgen driving prostatic growth); cause gland shrinkage (~20-25% volume reduction over 6-12 months)
• Drugs: Finasteride (5 mg OD - type II 5AR), Dutasteride (0.5 mg OD - types I and II 5AR)
• Onset: Slow - 6-12 months for full effect
• Benefits: Reduce long-term risk of acute urinary retention and need for surgery; PSA reduced by ~50% (must double PSA for cancer screening)
• Side effects: Erectile dysfunction, reduced libido, ejaculatory dysfunction, gynecomastia, teratogenic in pregnancy
• Best for large prostates (>30-40 g) with elevated PSA

Combination Therapy

• Alpha-blocker + 5-ARI shown superior to either drug alone for long-term outcomes (MTOPS and CombAT trials)
• Combination of tamsulosin + dutasteride (Duodart/Jalyn) is available

Phosphodiesterase-5 Inhibitors (PDE5i)

• Tadalafil 5 mg OD approved for LUTS/BPH
• Mechanism: Smooth muscle relaxation via cGMP pathway
• Useful when BPH coexists with erectile dysfunction

Antimuscarinics / Beta-3 Agonists

• For storage symptoms (OAB component) alongside alpha-blockers
• Mirabegron (beta-3 agonist) - fewer side effects than antimuscarinics

3. Surgical Management

• Acute urinary retention (AUR) unresponsive to or recurring after catheter trial
• Chronic urinary retention with renal impairment (azotemia)
• Recurrent UTI due to incomplete bladder emptying
• Recurrent hematuria unresponsive to 5-ARIs
• Bladder calculi
• Bladder diverticula

Transurethral Resection of the Prostate (TURP) - Gold Standard

• Resectoscope via urethra, electrocautery loop resects periurethral adenoma
• Dramatic improvement in IPSS, Qmax, PVR
• TUR syndrome: Dilutional hyponatremia from absorption of glycine irrigation fluid (monopolar TURP) - presents with confusion, hyponatremia, cardiovascular instability
• Bipolar/laser TURP: Uses saline irrigation - eliminates TUR syndrome, less bleeding
• Retrograde ejaculation: Occurs in ~65-90% of cases (due to destruction of bladder neck mechanism)

Laser Procedures

• HoLEP (Holmium Laser Enucleation of the Prostate): Enucleates entire adenoma, suitable for large prostates; outcomes equivalent to open prostatectomy; minimal bleeding; shorter hospital stay
• PVP (Photoselective Vaporization of the Prostate / GreenLight): Vaporizes prostatic tissue; good for patients on anticoagulants

Open Simple Prostatectomy (Millin's Retropubic / Freyer's Transvesical)

• For very large prostates (>80-100 g) not amenable to transurethral procedures
• Enucleation of adenoma via retropubic or transvesical approach
• Long historical use; excellent outcomes

Minimally Invasive Procedures

• UroLift (Prostatic Urethral Lift): Mechanical retraction of prostatic lobes; preserves ejaculatory function; for smaller prostates
• Rezum (Water Vapor Thermal Therapy): Steam injection into prostate tissue
• TUNA (Transurethral Needle Ablation): Radiofrequency ablation
• TUMT (Transurethral Microwave Thermotherapy): Microwave heat

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Q.3a (10 marks) - Acute Appendicitis

ACUTE APPENDICITIS

Pathophysiology

• Luminal obstruction is the primary event: fecalith (most common), lymphoid hyperplasia (in children - following viral infection), mucus plug, parasites (Enterobius), foreign body, rarely carcinoid tumor
• Obstruction - bacterial overgrowth - increased intraluminal pressure - venous congestion - ischemia - mucosal ulceration - bacterial invasion of wall - perforation

Clinical Features

• Pain: Begins as poorly localized periumbilical colicky pain (visceral; T10 dermatome from appendicular stretch) that migrates to right iliac fossa (RIF) within 6-8 hours (somatic; parietal peritoneum involvement) - pathognomonic sequence
• Anorexia: Almost universal (absence makes diagnosis questionable)
• Nausea and vomiting: Follow the pain (if vomiting precedes pain, consider gastroenteritis)
• Low-grade fever (37.5-38°C); higher fever suggests perforation/abscess
• Altered bowel habit, dysuria/frequency (pelvic appendix)

• McBurney's point tenderness: 1/3 from ASIS to umbilicus; maximum tenderness point
• Rebound tenderness (Blumberg's sign): Peritoneal irritation
• Rovsing's sign: Pressure in LIF causes pain in RIF (peritoneal irritation)
• Psoas sign: Extension of right hip causes RIF pain (retrocaecal appendix)
• Obturator sign: Internal rotation of right hip causes RIF pain (pelvic appendix)
• Guarding and rigidity: Localized (appendicitis) or generalized (perforation with peritonitis)
• Dunphy's sign: Increased pain on coughing

• Elderly: vague symptoms, delayed presentation, higher perforation rate
• Children <5 years: higher perforation rate due to underdeveloped omentum
• Pregnant women: appendix displaced superiorly by uterus; RUQ pain possible; MRI preferred
• Pelvic appendix: urinary symptoms, diarrhea
• Retrocaecal appendix (most common position - 65%): minimal anterior guarding, positive psoas sign

Investigations

• WBC: Leukocytosis (12,000-18,000); left shift (immature neutrophils); very high WBC >18,000 suggests perforation
• CRP: Elevated; rises with duration of inflammation; useful in equivocal cases
• Urinalysis: Exclude UTI; sterile pyuria and microscopic hematuria can occur from adjacent ureteral irritation (do not dismiss appendicitis)
• Serum beta-hCG: Mandatory in all females of reproductive age to exclude ectopic pregnancy
• Serum amylase/lipase: To exclude pancreatitis

• Plain X-ray: Not diagnostic; may show fecalith (5%), localized ileus, scoliosis away from pain
• Ultrasound (USS): Sensitivity 86%, specificity 81%; non-compressible appendix >6 mm, periappendiceal fat echogenicity; operator-dependent; first-line in children and pregnant women
• CT Abdomen (with IV contrast) - Most Accurate:
  • Appendix diameter >10 mm = diagnostic; periappendiceal fat stranding, appendicolith, free fluid
  • Sensitivity ~95%, specificity ~95%
  • Reduced negative appendectomy rate to ~5%
  • Radiation concern limits use in young/pregnant patients
• MRI: Choice in pregnancy; no radiation; sensitivity and specificity approaching CT

• Alvarado Score (MANTRELS): Maximum 10 points - migration of pain (1), anorexia (1), nausea (1), tenderness RLQ (2), rebound tenderness (1), elevated temperature (1), leukocytosis (2), left shift (1)
  • 5-6: Suggestive - evaluate with imaging
  • 7-8: Probable - consider surgery
  • 9-10: Almost certain appendicitis
• AIR Score (Appendicitis Inflammatory Response)
• Adult Appendicitis Score (AAS)

Management

• Evidence supports antibiotics alone (amoxicillin-clavulanate or cefazolin + metronidazole) for uncomplicated appendicitis in selected patients (Scandinavian APPAC trial)
• 25-30% recurrence rate within 1 year; 72% success at 5 years
• Patient counseling regarding recurrence and risk of missing perforated appendicitis is essential

• Laparoscopic appendicectomy: Preferred; shorter hospital stay, faster recovery, better visualization of pelvis, lower wound infection rate; standard of care
• Open appendicectomy (Lanz/McBurney incision): When laparoscopy unavailable or contraindicated
• Pre/peri-operative antibiotics: Reduce wound infection (single dose of cefazolin + metronidazole)
• IV fluids and analgesia: Opioid analgesia does NOT mask signs and should not be withheld

• Perforated appendicitis: Urgent surgery; peritoneal lavage; prolonged antibiotic course
• Appendix mass (phlegmon): Initial non-operative management (IV antibiotics, fluids) - resolves in most cases; interval appendicectomy at 6-8 weeks is controversial (now often not performed)
• Appendix abscess: Percutaneous CT-guided drainage + IV antibiotics; delayed appendicectomy if recurrence

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Q.3b (10 marks) - Non-Palpable Testes (Cryptorchidism)

NON-PALPABLE TESTES

Definition and Incidence

• Undescended testis (UDT/cryptorchidism): A testis not present in the scrotum at birth, unable to be manipulated into the normal scrotal position
• Incidence: 2-4% of term male infants; 30% in premature infants; spontaneous descent occurs in most by 3 months; final prevalence ~1% at 1 year of age
• Non-palpable testis = cannot be felt anywhere along the normal path of descent (accounts for ~20% of UDT)

Classification

By Location

1. Intra-abdominal (most common non-palpable - ~50%): Above the internal inguinal ring
2. Intracanalicular: Within the inguinal canal
3. Ectopic: Normal descent but deviated to an abnormal site (superficial inguinal pouch - most common ectopic site; perineum; femoral; transverse ectopia)
4. Retractile: Normal testis drawn up by overactive cremasteric reflex; can be manipulated into scrotum and remains there - no treatment needed
5. Vanishing (absent) testis (~20% of non-palpable): Testicular atrophy/antenatal torsion; no viable testicular tissue

Why Non-Palpable?

• Testis is truly absent
• Intracanalicular but cannot be palpated due to obesity/non-cooperation
• Intra-abdominal position
• Atrophic testicular nubbin

Consequences of Undescended Testis

1. Infertility: Spermatogenesis requires 2°C cooler than body temperature; bilateral UDT has 70-90% infertility if uncorrected; even unilateral UDT affects contralateral testis
2. Malignancy: 4-10x increased risk of testicular germ cell tumors (seminoma > teratoma); risk persists even after orchidopexy but early surgery reduces it; orchidopexy also facilitates self-examination
3. Torsion: Increased risk in undescended testis
4. Psychological: Empty scrotum
5. Associated anomalies: Patent processus vaginalis/hernia (~95%), hypospadias

Assessment

• Was testis present at birth? (Retractile vs. true UDT)
• Gestational age, birth weight
• Previous surgery or manipulation
• Family history of UDT
• Hypospadias, ambiguous genitalia (consider DSD)

• Bimanual examination: one hand pushing from ASIS downward, other palpating scrotum and inguinal canal
• Truly impalpable: Cannot be brought into scrotum with gentle pressure
• Contralateral testis: compensatory hypertrophy suggests absent/atrophic opposite testis
• Check for hernia

• Ultrasound: Limited sensitivity for intra-abdominal testes (~50%); useful for inguinal canal; should NOT delay surgery if impalpable
• MRI: Better for intra-abdominal testes (sensitivity ~60-80%); still not 100% accurate
• Laparoscopy (gold standard for non-palpable testis): Diagnostic AND therapeutic; reveals:
  • Blind-ending vas + vessels (vanishing testis) - no further action needed
  • Vessels/vas entering internal ring - testis present, proceed to exploration
  • Intra-abdominal testis - proceed to laparoscopic orchidopexy
• Hormonal testing: hCG stimulation test (testosterone rise confirms viable testicular tissue); AMH/inhibin B (markers of Sertoli cell function); LH/FSH (elevated in bilateral absence)
• Karyotype: If bilateral non-palpable testes in phenotypic male or any DSD features

Management

Timing

• Orchidopexy should be performed at 6-12 months, no later than 18 months
• Early orchidopexy optimizes germ cell numbers and fertility potential

Surgical Approach for Non-Palpable Testis

• If blind-ending cord structures above internal ring: testis absent - no further surgery
• If cord structures entering ring: inguinal exploration
• If intra-abdominal testis close to ring: laparoscopic or standard orchidopexy possible

• Laparoscopic orchidopexy: Mobilize testis with adequate length of vas and vessels; create scrotal pouch (Dartos pouch); fix testis in scrotum
• Inguinal orchidopexy: Gridiron incision, mobilize testis, ligate processus vaginalis (hernia sac), place in Dartos pouch

• When testicular vessels are too short for single-stage scrotal placement
• Stage 1: Divide spermatic vessels (laparoscopic or open) - collateral blood supply via vasal vessels develops over 6 months
• Stage 2: Six months later - orchidopexy based on vasal blood supply
• Success rate ~70-90%

• Testicular vessels anastomosed to inferior epigastric vessels; rarely used

• Indicated for atrophic nubbin or dysplastic testis without viable tissue
• Bilateral anorchia: testosterone replacement at puberty

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Q.4a (10 marks) - Ulcerative Colitis

ULCERATIVE COLITIS

Definition and Epidemiology

• Incidence: 6-8/100,000 population/year (highest in Northern Europe, North America)
• Bimodal age distribution: peaks at 15-30 years and 50-70 years
• Equal sex distribution; increased risk in non-smokers

Pathology

• Continuous mucosal inflammation starting from rectum
• Congested, hyperemic, friable mucosa that bleeds on contact
• Shallow mucosal ulcers
• Inflammatory (pseudopolyps): Islands of regenerating mucosa between ulcers appear as polypoid projections
• Shortened, narrowed colon (lead-pipe colon) in chronic disease
• Loss of haustra (featureless or "drainpipe" colon on barium enema)

• Crypt abscesses (neutrophil infiltration into crypts) - characteristic
• Goblet cell depletion
• Mucosal ulceration
• Lamina propria inflammatory infiltrate (lymphocytes, plasma cells)
• Changes limited to mucosa and submucosa (cf. Crohn's = transmural)

Clinical Presentation

• Bloody diarrhea with mucus: Cardinal symptom; urgency, tenesmus
• Frequency: 4-20 loose motions/day depending on severity
• Abdominal cramping pain preceding defecation
• Weight loss in severe disease

• Joints: Peripheral arthropathy (parallels bowel disease), ankylosing spondylitis (HLA-B27 positive, independent of bowel activity)
• Skin: Erythema nodosum (parallels), pyoderma gangrenosum (may be independent)
• Eyes: Episcleritis (parallels), uveitis/iritis (may be independent)
• Liver: Primary sclerosing cholangitis (PSC) - 5-8% of UC patients; may be independent; pANCA positive
• Others: Aphthous mouth ulcers, venous/arterial thrombosis (hypercoagulable state)

Investigations

• CBC: Anemia (iron deficiency from blood loss), leukocytosis, thrombocytosis
• ESR, CRP: Disease activity markers
• Albumin: Low in severe disease (poor nutrition, protein-losing enteropathy)
• LFTs: Baseline and for PSC screening
• ANCA: pANCA positive in ~60-70% of UC (vs. ASCA positive in Crohn's)

• Stool culture: Exclude infectious colitis (Clostridium difficile, Campylobacter, Salmonella, E. coli O157)
• Fecal calprotectin: Elevated; correlates with mucosal inflammation; useful for monitoring

• Flexible sigmoidoscopy/colonoscopy with biopsy: Gold standard
• Demonstrates mucosal friability, granularity, continuous involvement from rectum, loss of vascular pattern
• Multiple biopsies from different segments to assess extent and dysplasia
• Caution: Avoid colonoscopy in fulminant/toxic megacolon (risk of perforation)

• Plain AXR: In severe attack: assess extent of mucosal disease, exclude toxic megacolon
• Double-contrast barium enema: "Lead pipe" colon, loss of haustra, pseudopolyps (largely replaced by colonoscopy)
• CT scan: Bowel wall thickening, pericolic fat stranding; detects toxic megacolon/perforation
• CT colonography/MRI colonography: For patients unfit for colonoscopy

Complications

1. Toxic Megacolon: Transverse colon >6 cm on AXR; sepsis, shock; high mortality; emergency colectomy
2. Perforation: Spontaneous or associated with toxic megacolon
3. Hemorrhage: Massive, life-threatening
4. Stricture/Carcinoma: Risk of colorectal carcinoma increases with duration - 2% at 10 years, 8% at 20 years, 18% at 30 years; requires surveillance colonoscopy every 1-2 years after 8-10 years of pancolitis

Management

1. Mild-to-Moderate UC:
   • 5-Aminosalicylates (5-ASA/mesalazine): First-line; topical (enemas, suppositories) + oral; induces and maintains remission; Sulfasalazine is original agent (now superseded due to side effects)
   • Rectal mesalazine suppositories for proctitis
   • Oral + rectal combination superior to either alone
2. Moderate-to-Severe UC (in-patient):
   • Systemic corticosteroids: Prednisolone 40 mg/day orally or IV hydrocortisone 100 mg 6-hourly
   • IV fluids, electrolyte correction, nutritional support (TPN if needed)
   • DVT prophylaxis (UC is a hypercoagulable state)
   • Regular AXR and clinical monitoring
   • Stool cultures to exclude C. difficile superinfection
3. Steroid-Refractory/Dependent Disease:
   • Calcineurin inhibitors: IV ciclosporin (cyclosporine) - rescue therapy to avoid emergency colectomy in acute severe UC; response within 7 days
   • Biologic therapy:
     • Anti-TNF agents: Infliximab (IV), Adalimumab (SC) - first-line biologics
     • Anti-integrin: Vedolizumab (gut-selective, targets alpha-4-beta-7 integrin)
     • Anti-IL-12/23: Ustekinumab
   • Thiopurines (Azathioprine/6-Mercaptopurine): Maintenance of remission; not for acute induction; require TPMT enzyme testing before starting

• Emergency: Fulminant colitis unresponsive to 48-72 hours of IV therapy, toxic megacolon, perforation, massive hemorrhage
• Elective: Medically refractory disease, dysplasia/carcinoma, complications of medications

1. Emergency: Subtotal colectomy + end ileostomy + hartmann pouch or mucous fistula (quickest, safest)
2. Elective - Restorative Proctocolectomy with Ileal Pouch-Anal Anastomosis (IPAA/J-pouch): Procedure of choice for young, fit patients; removes entire disease burden; avoids permanent stoma; J-pouch constructed from terminal ileum
3. Total Proctocolectomy + Permanent Ileostomy: For patients unsuitable for pouch (poor sphincter function, elderly, carcinoma of low rectum)

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Q.4b (10 marks) - Intestinal Obstruction

INTESTINAL OBSTRUCTION

Definition

Classification

• Mechanical obstruction: Physical blockage (most common clinically significant form)
• Functional (Paralytic ileus/Pseudo-obstruction): No mechanical block; failure of peristalsis due to neuromuscular dysfunction

• Gallstone ileus
• Bezoar, swallowed foreign body
• Meconium (neonates)
• Intussusception (children - most commonly ileocolic)

• Carcinoma of colon (most common cause of large bowel obstruction in adults)
• Crohn's disease (fibrous stricture)
• Diverticular disease
• Ischemic stricture
• Congenital atresia/stenosis

• Adhesions (most common cause of small bowel obstruction - 75% of cases; post-surgical)
• Hernias: Inguinal, femoral, paraumbilical, incisional (second most common cause of SBO; ~30%)
• Volvulus: Sigmoid (common in elderly, chronic constipation) or caecal
• Compression by tumor/abscess

• Small bowel obstruction (SBO) vs. Large bowel obstruction (LBO) - management differs

• Simple obstruction: Blood supply intact
• Strangulated obstruction: Vascular compromise - leads to ischemia, gangrene, perforation - surgical emergency

Pathophysiology

• Luminal obstruction causes distension proximal to obstruction
• Accumulation of gas (swallowed air, bacterial fermentation) and fluid (up to 6 L/day of intestinal secretions)
• Vomiting leads to dehydration, electrolyte disturbance (hypokalemia, hyponatremia, metabolic alkalosis in proximal SBO; metabolic acidosis in late SBO)
• Bacterial translocation with mucosal barrier breakdown
• Strangulation: Arterial or venous occlusion - ischemia - mucosal necrosis - gangrene - perforation - peritonitis - sepsis

Clinical Features

1. Colicky abdominal pain: Intermittent, wave-like; coincides with peristaltic waves trying to overcome obstruction
2. Vomiting:
   • Proximal SBO: early, profuse, bilious vomiting
   • Distal SBO: late, feculent (bacterial action on stagnant contents)
   • LBO: late, feculent
3. Abdominal distension:
   • Proximal SBO: minimal (vomiting decompresses)
   • Distal SBO/LBO: pronounced central/peripheral distension
4. Absolute constipation (obstipation): No flatus or stool per rectum; may be absent early if stool distal to obstruction still passed

• Dehydration (tachycardia, dry tongue, reduced skin turgor, low BP)
• Abdominal distension with visible peristalsis (in thin patients)
• High-pitched, tinkling "metallic" bowel sounds coinciding with colic
• Later: absent bowel sounds (exhausted bowel)
• Tenderness: localized over strangulated segment
• Always examine hernial orifices (inguinal, femoral, umbilical) - incarcerated hernia is a common cause
• Rectal examination: empty rectum in obstruction; carcinoma felt as mass

• Fever, tachycardia, persistent/continuous pain (not colicky anymore)
• Localized tenderness, rigidity, peritonism
• Leukocytosis >18,000, metabolic acidosis, raised lactate
• Failure to improve with conservative management

Investigations

• WBC: Leukocytosis; marked elevation (>18,000) or neutrophilia suggests strangulation/infarction
• U&E: Hyponatremia, hypokalemia, raised creatinine (dehydration)
• Serum lactate: Elevated in bowel ischemia
• Serum amylase: Mildly elevated (especially in strangulation)
• ABG: Metabolic alkalosis (early), metabolic acidosis (late strangulation)
• Blood cultures: If sepsis suspected

1. Plain AXR (Erect + Supine) - First-Line:
   • Erect: Multiple air-fluid levels in dilated loops
   • Supine: Pattern of distended loops
   • SBO: Central dilated loops; valvulae conniventes (plicae circulares) visible - thin transverse lines traversing entire bowel width; "stepladder" pattern
   • LBO: Peripheral dilated loops; haustra visible - incomplete transverse lines not crossing full width; distal cut-off at site of obstruction
   • Rigler's sign: Air on both sides of bowel wall = pneumoperitoneum (perforation)
   • Caecal diameter >9 cm on LBO - at risk of perforation
   • Pneumobilia suggests gallstone ileus
2. CT Abdomen and Pelvis (with IV/oral contrast) - Gold Standard:
   • Identifies level, site, and cause of obstruction
   • Detects strangulation: bowel wall thickening, pneumatosis intestinalis, mesenteric fat stranding, portal venous gas
   • Identifies transition point
   • Detects complications (perforation, abscess)
3. Water-Soluble Contrast Enema:
   • For LBO: Identifies site and nature of obstruction (carcinoma vs. diverticular vs. volvulus)
   • Gastrografin in SBO: Therapeutic + diagnostic; may stimulate peristalsis and resolution
4. Colonoscopy:
   • Diagnostic + therapeutic for sigmoid/cecal volvulus (detorsion and decompression)

Management

Initial Resuscitation ("Drip and Suck")

• IV access, large-bore cannula
• IV fluids: Normal saline + KCl for volume resuscitation and electrolyte correction
• Nasogastric tube (NGT) on free drainage: Decompresses stomach, reduces vomiting risk and aspiration
• Urinary catheter: Monitor urine output (target >0.5 mL/kg/hr)
• Analgesia: Opioid analgesia (does not mask signs, is humane)
• Antibiotics: If strangulation, perforation, or peritonitis suspected (broad-spectrum IV)
• DVT prophylaxis: LMWH + compression stockings

Conservative Management (SBO)

• Adhesive SBO (non-strangulated, partial): 60-80% resolve with conservative management (NGT, IV fluids, observation 24-48 hours)
• Gastrografin challenge: Water-soluble contrast given via NGT; therapeutic + diagnostic; if contrast reaches colon within 24 hours, predicts non-operative resolution
• Close monitoring for signs of strangulation mandating surgery

Surgical Management

• Strangulation (suspected or confirmed)
• Perforation/peritonitis
• Closed-loop obstruction (caecal diameter >9 cm in LBO with competent ileocaecal valve)
• Failure of conservative management (48-72 hours)
• Hernia with incarceration/strangulation

• Explore abdomen (laparoscopic or open)
• Identify and relieve cause of obstruction
• Assess bowel viability: warm saline-soaked packs, assess color, peristalsis, Doppler
• Resect non-viable bowel
• SBO due to adhesions: Divide adhesion/band; resect non-viable segment
• LBO (carcinoma):
  • Right-sided: Right hemicolectomy + primary anastomosis
  • Left-sided: Hartmann's procedure (resect + end colostomy) for emergency; or on-table lavage + primary anastomosis in fit patients
  • Obstructing colorectal cancer: Endoscopic stent as bridge to elective surgery in selected cases
• Sigmoid volvulus: Flexible sigmoidoscopy + flatus tube decompression first; elective sigmoid resection after stabilization; Hartmann's if gangrenous
• Hernias: Herniotomy + assessment of bowel viability; resect gangrenous bowel

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Quick Reference Summary

Key Exam Points to Remember:

• Q1 - Safe Cholecystectomy: Strasberg's Critical View of Safety (CVS) - the most examinable concept; never clip until CVS achieved
• Q2 - IPSS scoring: Mild 0-7, Moderate 8-19, Severe 20-35; TURP gold standard surgical treatment
• Q3a - Alvarado Score: MANTRELS mnemonic; score ≥7 = likely appendicitis; CT has ~95% sensitivity
• Q3b - Non-palpable testis: Laparoscopy is gold standard for diagnosis AND treatment; Fowler-Stephens for high testes
• Q4a - UC: Always rectum first, continuous, mucosal only; Truelove-Witts criteria; IPAA/J-pouch for young fit patients
• Q4b - Intestinal Obstruction: "Drip and suck"; examine hernial orifices; strangulation = emergency surgery; SBO valvulae conniventes vs. LBO haustra on X-ray