Emergency Medicine

Infectious Disease and Foreign Travel Emergencies 149

GASTROINTESTINAL TRACT INFECTION

(vii) ‘Traveller’s diarrhoea’ is most often due to enterotoxigenic

Escherichia coli, and is usually self-limiting over 2–5 days, causing

watery stools and occasionally vomiting. Fever is unusual,

and may indicate a more serious infection that needs active

investigation, including malaria or even epidemic influenza.

3 The most important feature in all cases, after establishing a contact or travel
histor y, is clinica l ev idence of dehydration.
(i) Dehydration causes thirst, lassitude, dry lax skin, tachycardia and
postural hypotension, leading to oliguria, confusion and coma
when critical.

4 Also consider other causes of acute diarrhoea including drug-related,
Clostridium difficile antibiotic-related diarrhoea (CDAD), Crohn’s disease,
ulcerative colitis, ischaemic colitis, irritable bowel syndrome, and ‘spurious’
from faecal impaction.

5 Send blood for FBC and ELFTs, and commence an i.v. infusion of normal
saline in all dehydrated, febrile or toxic patients.
(i) Send a stool specimen for C. difficile toxin assay, if antibiotic-
associated diarrhoea is suspected following any antibiotic use in
the previous 8 weeks.

MANAGEMENT

1 Admit dehydrated, toxic, very young or elderly, and immunosuppressed
patients for rehydration.

2 Allow other patients home and encourage them to drink plenty of f luid.
(i) Alternatively, give the patient an oral glucose and electrolyte
rehydration solution, which may also be purchased over the
counter.
(ii) Give an antimotility agent such as loperamide 4 mg initially,
followed by 2 mg after each loose stool to a maximum of 16 mg/
day (not in children).

3 Ask the patient to return within 24–48 h if symptoms persist:
(i) Send stools for microscopy and culture then.
(ii) Consider empirical treatment for moderate to severe systemic
illness with bloody diarrhoea or for associated rigors
(a) give ciprofloxacin 500 mg orally b.d. for 5–7 days (not in
children).
(iii) Give tinidazole 2 g orally once if Giardia is suspected.

4 Arrange follow-up in medical outpatients or by the local GP.
(i) Stop any antibiotics if CDAD is confirmed and give
metronidazole 400 mg orally t.d.s. for 7 days.