Antibiotics for acute cholecystitis — OSCE prescribing station

The stem

Mrs Hamdan is admitted with 2 days of right upper quadrant pain and fever. She has a positive Murphy’s sign. Ultrasound shows gallstones with a thick-walled gallbladder and fluid around it. She is not septic. Prescribe her antibiotics.

Patient details

Patient: Mrs Rana Hamdan, 48 years
Weight: 72 kg
Allergies: Penicillin: “a rash as a child”
Temperature: 38.3 °C
White cells: 15.4 ×10⁹/L
eGFR: 92 mL/min/1.73 m²
Bilirubin: Normal

Drug chartTo write

Drug (generic name)	Dose	Route	How often / rate	Notes

Write the drug, dose, route and frequency, and sign every entry.

The examiner’s questions

Question 1What do you ask about her allergy before prescribing?Show the model answer

What happened, when, and how it was treated. A rash in childhood without breathing difficulty, swelling or collapse is a non-severe reaction. Anaphylaxis, angioedema, or a severe skin reaction such as Stevens–Johnson syndrome is severe. Record the drug and the reaction in the allergy box either way.

Question 2Prescribe her antibiotics.Show the model answer

She has a non-severe penicillin allergy, so avoid penicillins such as co-amoxiclav. A cephalosporin is reasonable because cross-reactivity is low.

Drug (generic name)	Dose	Route	How often / rate	Notes
Ceftriaxone	2 g	IV	Once daily	Indication: acute cholecystitis. Review at 48 to 72 hours
Metronidazole	500 mg	IV	Every 8 hours	Indication: acute cholecystitis. Review at 48 to 72 hours

If her reaction had been severe, avoid all beta-lactams and use your local alternative, for example ciprofloxacin with metronidazole, after discussion with microbiology. Always follow your hospital’s antibiotic guideline.

Question 3What must you do before giving the first dose, and when is the antibiotic stopped?Show the model answer

Take blood cultures if she is febrile, without delaying treatment. Write the indication and a review date on the chart. Review at 48 to 72 hours: change to oral, narrow according to culture results, or stop. After early cholecystectomy, antibiotics can usually be stopped within 24 hours in mild to moderate cholecystitis; longer courses are for severe disease or complications such as empyema or perforation.

Question 4What is the definitive treatment?Show the model answer

Early laparoscopic cholecystectomy, ideally within 72 hours of admission and within a week of diagnosis, if she is fit for surgery. If she is too unwell, a percutaneous cholecystostomy drains the gallbladder.

After you answerThe teaching pointShow

Antibiotics treat the infection; the operation removes the source. Write the indication and a review date on every antibiotic prescription.

Related: Imaging station 5 →

The patients are written for teaching and are not real. Doses are typical adult doses; always check the current formulary and your hospital’s guidelines before prescribing.