MRCP2-2912

MRCP2-2912

A 35-year-old backpacker presents to the Emergency Department with severe fever, left-sided lower abdominal pain and bloody diarrhea over the past 48 hours. He has no significant medical history and does not take any regular medication. He has been staying in hostels over the past few days where cooking and bathroom facilities are shared.

On examination, his blood pressure is 120/80 mmHg, with a postural drop of 20 mmHg on standing, and his pulse is 90 bpm.

Investigations:
Haemoglobin (Hb) – 142 g/l (normal range: 135–175 g/l)
White cell count (WCC) – 11.8 × 109/l (normal range: 4–11 × 109/l)
Platelets (PLT) – 190 × 109/l (normal range: 150–400 × 109/l)
Sodium (Na+) – 140 mmol/l (normal range: 135–145 mmol/l)
Potassium (K+) – 3.8 mmol/l (normal range: 3.5–5.0 mmol/l)
Creatinine – 120 µmol/l (normal range: 50–120 µmol/l)
Urea – 9.5 mmol/l (normal range: 2.5–7.8 mmol/l)
C-reactive protein (CRP) – 180 mg/l (normal range: < 5 mg/l)
Stool screen: Positive for Campylobacter.

He is given oral rehydration sachets and expresses his desire to continue his trip. What is the most appropriate additional intervention?