Gastrointestinal tract

Antimicrobial therapy seldom indicated unless systemic invasion is suspected. Consult Microbiology before starting antibiotics.

In the presence of bloody diarrhoea, consider the possibility of infection with E. Coli 0157. Unless the patient is septic, antibiotics are not appropriate for bloody diarrhoea because of the risk of precipitating Haemolytic Uraemic Syndrome.  Seek microbiologist advice.

Obtain travel history for all cases.

Initial management is supportive until a pathogen has been isolated.

Give empirical antibiotic treatment if:

• Confirmed or suspected sepsis
• Age <6 months
• Immunocompromised
• Malnourished
• Haemoglobinopathy and suspected Salmonella gastroenteritis

Those with bacteraemia will require prolonged IV therapy.  Discuss with microbiology.

Salmonella

Cefotaxime IV

Duration: 10-14 days

Shigella / Campylobacter

Ciprofloxacin oral

Duration: 5 days

Beware of complications e.g. osteomyelitis, meningitis. If these present, treatment should be given for longer.

Seek Microbiologist advice

Cefotaxime IV

Treat bacteraemia and severe infection treat for 10-14 days.

Mild or moderate:

Metronidazole PO

Duration: 10 to 14 days. Stop at day 10 if symptoms resolved

As indicated by any of the following:

• Immunocompromised
• Abdominal tenderness
• Fever
• Raised WCC
• Declining renal function

Duration: 10 to 14 days. Stop at day 10 if symptoms resolved.

If patient unable to tolerate oral or NG vancomycin, give Metronidazole intravenously

Do not use Vancomycin IV

Seek urgent GI or surgical review

Vancomycin PO (high dose)

Plus

Metronidazole IV

Concomitant surgical management is important.

Patients with complicated peritonitis, previously treated with broad-spectrum antibiotics are at risk of infection with multi-resistant organisms.

In addition empirical antifungal therapy (e.g. fluconazole) may be considered for patients with complicated postoperative intra-abdominal infections.

Cefotaxime IV

Plus

Metronidazole IV

If true penicillin allergy: Seek Microbiology advice

Duration: Minimum 7 days

Seek urgent surgical and GI review

In patients with liver disease and ascites consider peritoneal tap and send aspirate for urgent microscopy and culture. Prophylaxis may be required after treatment of infection. Seek GI advice

Cefotaxime IV

Plus

Metronidazole IV

If true penicillin allergy: Seek Microbiology advice 

The role of antibiotics in uncomplicated acute cholecystitis remains unclear.

If not improving, consider adding gentamicin and seek microbiology advice.

Cefotaxime IV

Plus

Metronidazole IV

Duration: 7-10 days

If true penicillin allergy: Seek Microbiology advice