Abdominal Pain OSCE - Appendicitis

Case Overview

• Age/Sex: 18-year-old male
• Occupation: College student, semi-professional soccer player
• Setting: Emergency department / urgent assessment clinic
• Chief complaint: "My lower belly really hurts"

Patient Script

Who I Am

I'm an 18-year-old college student who plays soccer for my college team and lives at home with my parents.

What Brings Me In

My stomach has been aching since yesterday and it’s getting worse on the right side — I thought it might pass but now I'm worried.

My Story

It started about 24 hours ago with a dull pain around my belly button that I thought was indigestion after dinner. Over the next 12 hours the pain moved and now it's a sharper pain in the lower right side of my belly. It's been getting worse — it's about 7 out of 10 now, worse when I walk, cough or move. I felt a bit hot last night and checked my temperature this morning — it was about 38°C. I felt sick and had one episode of vomiting about 6 hours ago and I haven't really felt like eating since the pain started.

I trained with the team yesterday afternoon and thought maybe I pulled something, but the pain is more in my tummy than in a muscle. I took some ibuprofen last night which helped a little at first. I also had one loose stool yesterday evening after dinner — I thought maybe I’d just eaten something off, but the diarrhea didn't continue.

My Medical Background

• Past medical history: No serious illnesses, no surgeries.
• Medications: None regularly; took one ibuprofen last night for pain.
• Allergies: None known.
• Social: Lives with parents, non-smoker, drinks alcohol occasionally, uses marijuana rarely; plays soccer regularly.
• Sexual history: Sexually active with one partner; uses condoms usually. No penile discharge.
• Family history: Mother has asthma; otherwise no significant family illnesses.

What I Think & Worry About

• I think it might just be food poisoning or a pulled muscle from training.
• I’m worried it could be something serious that needs an operation, and I don’t want to miss playing or exams.

If You Ask Me About Other Symptoms...

• Appetite: "I have very little appetite since it started."
• Bowel movements: "I had one loose stool yesterday evening, but none since then."
• Vomiting: "Just the one time, about 6 hours ago."
• Fever/chills: "I felt hot and had chills last night; my temp was 38°C this morning."
• Urine: "No burning or frequency, I peed this morning and it felt normal."
• Testicles/penis: "No pain or swelling down there."
• Cough/sore throat: "I had a mild cough and sniffles for a couple of days — I thought it was just a bit of a cold."
• Recent trauma: "I played a full training session yesterday but didn't have any fall or direct blow to the belly."

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Clinical Summary

Examination

• General: Alert, slightly anxious, lying still on the bed.
• Vitals: Temperature 38.1°C, HR 102 bpm, BP 118/72 mmHg, RR 18/min, SpO2 99% on air.
• Abdomen: Soft but with focal tenderness in the right lower quadrant (maximal at McBurney's point); guarded on that side; mild rebound tenderness present. Bowel sounds present but slightly reduced. No visible bruising or distension.
• Special signs: Positive Rovsing's sign (pain in RLQ when palpating left lower quadrant). Psoas and obturator manoeuvres produce discomfort on the right. No flank tenderness.
• Genital exam: Testes normal on palpation, no tenderness, no swelling.

Investigations

• CBC: WBC 15.2 x10^9/L, neutrophils 86% (absolute neutrophilia) (suggests bacterial/inflammatory process)
• CRP: 52 mg/L (elevated, supports inflammation)
• Electrolytes & renal function: Na 139 mmol/L, K 4.1 mmol/L, creatinine 72 µmol/L (within acceptable range)
• Urinalysis (dip): Trace blood, no nitrites, no significant leukocytes (makes UTI less likely)
• Pregnancy test: Not applicable (male patient)
• Abdominal ultrasound (graded compression): Non-compressible blind-ending tubular structure in the right iliac fossa measuring 8 mm in diameter with surrounding echogenic fat (consistent with acute appendicitis)
• If ultrasound equivocal: CT abdomen/pelvis with contrast: Dilated appendix ~11 mm with periappendiceal fat stranding and no obvious perforation (if needed for equivocal cases)

Diagnosis

• Primary: Acute appendicitis

  • Evidence: Typical migratory abdominal pain from periumbilical to right lower quadrant over 24 hours, fever, anorexia, nausea/vomiting, raised WBC and CRP, focal RLQ tenderness with peritoneal signs, positive Rovsing's sign, and ultrasound showing non-compressible appendix >6 mm.

• Differentials and reasoning:

  • Gastroenteritis: Considered because of one episode of loose stool and vomiting, but localized RLQ focal peritonism, fever pattern and raised inflammatory markers make this less likely.
  • Mesenteric adenitis: Can mimic appendicitis, often after viral illness and common in younger patients; ultrasound would usually show mesenteric lymph nodes rather than an inflamed appendix.
  • Renal colic: Typically flank/loin pain radiating to groin with hematuria and colicky character — not matching history or exam.
  • Testicular torsion: Presents with acute scrotal pain and abnormal testicular exam; this patient has normal genital exam.
  • Inflammatory bowel disease (terminal ileitis): Possible but less acute; would more likely have prior GI history and persistent diarrhoea.

Management

• Immediate:

  • Nil by mouth (NPO) in preparation for possible surgery.
  • IV access and fluid resuscitation as needed (e.g., 0.9% NaCl bolus if clinically indicated).
  • Analgesia: IV opioids (e.g., morphine titrated) and/or IV paracetamol as required for pain control.
  • Antiemetic as needed (e.g., ondansetron).
  • Administer broad-spectrum IV antibiotics preoperatively (example: ceftriaxone plus metronidazole or cefuroxime plus metronidazole depending on local protocol).
  • Urgent surgical consultation for likely appendectomy (laparoscopic preferred in this demographic if available).
  • If diagnosis uncertain: consider CT abdomen/pelvis with contrast for further evaluation.

• Perioperative:

  • Consent discussion covering risk/benefit of appendectomy, possibility of laparoscopy, and potential complications (bleeding, infection, bowel injury).
  • Routine pre-op investigations and anaesthetic review.

• Postoperative:

  • Continue analgesia and IV fluids as required.
  • Transition to oral antibiotics/short course depending on intraoperative findings and microbiology.
  • Early mobilisation and wound care instructions; advise about return to sport and typical timelines (usually several weeks depending on recovery).

Key Learning Points

• Classic appendicitis often presents with periumbilical pain migrating to the right lower quadrant with anorexia, nausea, fever and localized peritoneal signs.

• In young patients, ultrasound is a useful first-line imaging modality; a non-compressible appendix >6 mm with surrounding inflammatory changes is highly suggestive of acute appendicitis. Elevated WBC and CRP support the diagnosis.

• Initial management includes NPO status, IV fluids, timely analgesia, preoperative IV antibiotics and urgent surgical review — do not delay surgical assessment when clinical suspicion is high.