The Center For Disease Dynamics, Economics & Policy

Complicated Intra-Abdominal Infection (Community-Acquired)

Clinical definition:

Suspected or confirmed peritonitis including perforation or leakage of intestinal contents into peritoneum

 

Neonate

Preferred antibiotic choice
Drug Formulation Dosage Duration
Combination therapy with:

Cefotaxime (IV)

PLUS

Metronidazole (IV)

Cefotaxime- Powder for injection: 250 mg per vial (as sodium salt) o   First week of life (7 days or less): 50 mg/kg/dose 12 hourly

o   8-20 days: 50 mg/kg/dose 8 hourly

o   21 days & older: 50 mg/kg/dose 6 hourly

5 – 10 days depending on response to clinical and surgical treatment
Metronidazole- Injection: 500 mg in 100- mL vial. o   First week of life (7 days or less): 7.5 mg/kg/dose 12 hourly

o   8 days of age & older: 7.5 mg/kg/dose 8 hourly, maximum dose 400 mg 8 hourly

Alternative antibiotic choice(s)
Combination therapy with:

Benzylpenicillin (IV)

PLUS

Gentamicin (IV)

PLUS

Metronidazole (IV)

 

Benzylpenicillin- Powder for injection: 600 mg (= 1 million IU); 3 g (= 5 million IU) (sodium or potassium salt) in vial. o   First week of life (7 days or less): 100 000 IU/kg/dose 8 hourly

o   8 days of age & older: 125 000 IU/kg/dose 6 hourly, maximum dose 5 million IU 6 hourly

5 – 10 days depending on response to clinical and surgical treatment
Gentamicin- Injection: 10 mg; 40 mg (as sulfate)/ mL in 2- mL vial. o   4 mg/kg/dose once daily

 

Metronidazole- Injection: 500 mg in 100- mL vial. o   First week of life (7 days or less): 7.5 mg/kg/dose 12 hourly

o   8 days of age & older: 7.5 mg/kg/dose 8 hourly, maximum dose 400 mg 8 hourly

If Benzylpenicillin (IV) unavailable, substitute with:

Ampicillin (IV)

Treat with Gentamicin (IV) PLUS Metronidazole (IV), as above.

Ampicillin- Powder for injection: 500 mg; 1 g (as sodium salt) in vial. o   First week of life (7 days or less): 50 mg/kg/dose 8 hourly

o   8 days of age & older: 50 mg/kg/dose 6 hourly

Infant, Child & Adolescent

Preferred antibiotic choice
Drug Formulation Dosage Duration
Combination therapy with:

Ceftriaxone (IV)

PLUS

Metronidazole (IV)

Ceftriaxone- Powder for injection: 250 mg, 1 g (as sodium slat) in vial 50 mg/kg/dose 12 hourly, maximum dose 2 g 12 hourly 5 days if source control has been achieved (e.g. laparotomy, washout, repair). Longer durations may be required if source control is delayed
Metronidazole- Injection: 500 mg in 100- mL vial.  

7.5 mg/kg/dose 8 hourly, maximum dose 400 mg 8 hourly

Alternative antibiotic choice(s)
Amoxicillin + clavulanic acid (IV) Powder for injection: 500 mg (as sodium) + 100 mg (as potassium salt); 1000 mg (as sodium) + 200 mg (as potassium salt) in vial. 30 mg/kg/dose of amoxicillin component 8 hourly, maximum dose 1.2 g 8 hourly 5 days if source control has been achieved (e.g. laparotomy, washout, repair). Longer durations may be required if source control is delayed
If poor response to treatment
Combination therapy with:

Piperacillin/tazobactam (IV)

PLUS

Amikacin (IV)

Piperacillin/tazobactam Powder for injection: 2 g (as sodium salt) + 250 mg (as sodium salt); 4 g (as sodium salt) + 500 mg (as sodium salt) in vial 100 mg/kg of piperacillin component/dose 8 hourly, maximum dose 4 g of piperacillin component 8 hourly 5 days if source control has been achieved (e.g. laparotomy, washout, repair). Longer durations may be required if source control is delayed
Amikacin- Injection: 250 mg (as sulfate)/mL in 2- mL vial 15 mg/kg/dose once daily, maximum dose 1.5 g
If piperacillin-tazobactam (IV) is not available or in case of confirmed drug allergy or medical contraindication
Ciprofloxacin (IV)

PLUS

Metronidazole (IV)

PLUS

Amikacin (IV)

Ciprofloxacin- Solution for IV infusion: 2 mg/ mL (as hyclate) 10 mg/kg/dose 8-12 hourly, maximum dose 400 mg 8-12 hourly 5 days if source control has been achieved (e.g. laparotomy, washout, repair). Longer durations may be required if source control is delayed
Metronidazole- Injection: 500 mg in 100- mL vial. 7.5 mg/kg/dose 8 hourly, maximum dose 400 mg 8 hourly
Amikacin- Injection: 250 mg (as sulfate)/mL in 2- mL vial 15 mg/kg/dose once daily, maximum dose 1.5 g

 

Principles of Stewardship:

  • Obtain a blood culture prior to starting antibiotic therapy.
  • Investigate TB as a cause in endemic areas.

Notes:

  • Consultation with a surgeon is frequently required in patients with complicated intra-abdominal infections.
  • Once the patient is improving clinically and tolerating oral feeds, consider switching to an oral antibiotic such as amoxicillin + clavulanic acid.