4.07 - Intra-abdominal Infections

A) Adults

Disease / Etiology

Preferred

Alternative

Comments


Biliary tract infection: 

Cholecytits, cholangitis, biliary sepsis or common duct obstruction 

Microorganisms:
Gram negative aeroebs: 
E coli
Klebsiella sp,

Enterococcus faecalis (less common)
Anaerobe rare unless there is biliary obstruction: Bacteroides (rarely- perforation, serious illness and bowel manipulation)
Yeast (rarely)
 

Co-amoxiclav 1.2 gm IV q8H 

In septic shock or needing ICU management or patient with risk of Pseudomonas:
Piperacillin / Tazobactam 4.5 gm IV q8H 

Clinical improvement: 
Co-amoxiclav 625 mg PO q12H 

OR 

Cefuroxime 500 mg PO q12H 
+
Metronidazole 400 mg PO q8H

 

Cefoperazone 1 - 2 gm IV q12H OR Ceftriaxone 2 gm IV q24H

Metronidazole 500 mg IV q8H 
± 
Gentamicin 3 - 5 mg/kg IV q24H if risk of Pseudomonas present
 
Duration: 7 days. 

To consider laparocsopic cystectomy during presentation. 
Blood cultures should be taken BEFORE antibiotics. 
Use susceptible testing to guide ongoing therapy.

*Fluoroquinolones cause collateral damage, should be used only when the other drugs are contraindicated.

Biliary drainage should be performed for moderate to severe cholangitis. 
Empirical agents should be changed according to bile C&S. 

Infectious Diarrhea

 
Acute mild to moderate diarrhea 
Virus: norovirus (usually)
Bacteria
Parasite (rarely)

 

To replace fluids. 
No antibiotics required.
 
Mild
: ≤ 3 unformed stools, minimal symptoms

Moderate: ≥ 3 unformed stools and/or symptomatic

Severe: fever (> 38.5oC), ≥ 6 unformed stool. Severe diarrhea in the elderly, fecal leucocytes ± bloody stools.

Ciprofloxacin resistance increasing for salmonella and campylobacter.
TMP-SMX resistant and Campylobacter resistance common in Asia.
 
Acute severe diarrhoea 
Campylobacter 
Yersinia
Salmonella
Aeromonas
Plesiomonas spshigella 






C difficile


Ciprofloxacin 500 - 750 mg PO q12H for 3 - 5 days.









If C diff suspected, to add Metronidazole 400 - 800 mg PO q8H for 10 - 14 days



Trimethoprim -Sulfamethoxazole (TMP-SMX) (TMP 80 mg/SMX 400 mg) 2 tablet PO q12H for 3 - 5 days


OR

Azithromycin 500 mg PO q24H for 3 days

Alternative,
Vancomycin 125 - 500mg PO q6H for 14 days

Hepatic Abscess

 
Pyogenic abscess:
Enterobacteriaceae
Strep anginosus/milleri (occasionally)
Enterococci
Bacteroides

 
Co-amoxiclav 1.2 gm IV q8H

If septic shock:
Piperacillin / Tazobactam 4.5 gm IV q8H
 
Cefoperazone 2 gm IV q24H 
OR Ceftriaxone 2 gm IV q24H 

Metronidazole 500 mg IV q8H

  
Duration: 4 - 6 weeks. 

Modify antibiotics according to culture.
Convert to oral once clinically improved. 
If no culture available, oral Augmentin can be used.


Amoebic abscess:
Entamoeba histolytica

Metronidazole 500 mg IV q8H

Switch to Metronidazole 400 mg PO q8H for 10 days when clinical improvement occurs.


Tinidazole 2 gm PO q24H for 3 - 5 days

Tinidazole not available in UMMC.

Acute Pancreatitis

 
Mild to moderate pancreatitis including alcoholic pancreatitis
 
Antibiotics not required
 



 
Severe non necrotizing pancreatitis

Antibiotics not required



 
Perform an image guided percutaneous aspiration before antibiotics.


Severe non infected necrotizing pancreatitis

 
Antibiotics not required
 
Prophylaxis antibiotics to prevent pancreatic infection are no longer recommended because of lack of benefit and possibly of harm.
Surgical debridement is the treatment of choice.
 

Severe infected necrotizing pancreatitis: infected pseudo cyst, pancreatic abscess
Enterobacteriaceae
Enterococci
Staph aureus
Streptococcus
Staph Epidemidis
Anaerobes
Candida spp (Rarely)


Imipenem* 500 mg IV q6H

Cefoperazone 1 - 2 gm IV q24H OR Ceftriaxone 2 gm IV q24H
+
Metronidazole 500 mg IV q8H or 400 mg PO q8H

* Deescalate antibiotic once culture and sensitivity result is available.
 
Prophylaxis antibiotics if > 30% of pancreas necrotic on CT scan
(CONTROVERSIAL)



Imipenem 500 mg IV q6H OR
Meropenem 1 gm IV q8H


Duration: if cultures are negative, stop antibiotics by Day 3.
Perform an image guided percutaneous aspiration before antibiotics.

Diverticular Disease


Diverticulitis, appendicitis, Peri-diverticular abscess, Peri-appendiceal abscess, Peritonitis due to Perforated viscus, Perirectal abscess:
Enterobacteriaceae
Enterococci (in perforation of large bowel)
Anaerobes

 
Co-amoxiclav 1.2 gm IV q8H

If patient is at risk of Pseudomonas infection:
Piperacillin / Tazobactam 4.5 gm IV q8H

 
Ceftriaxone 1 gm IV q24H
+
Metronidazole 500 mg IV q8H

Duration: 5 - 10 days

*Fluoroquinolone causes collateral damage.
 Should be used only when the other drugs are contraindicated.

Add Metronidazole if peritonitis, perforation or abscess present.

Spontaneous Bacterial Peritonitis (SBP)‡
Entereobacteriaceae (63%)
S. pneumoniae (15%) 
Enterococci (6-10%)
Anaerobes (uncommon)

 
Co-amoxiclav 1.2 gm IV q8H

If patient is at risk of Pseudomonas infection: Piperacillin / Tazobactam 4.5 gm IV q8H

 
Ceftriaxone 1 gm IV q24H
+
Metronidazole 500 mg IV q8H
 
Duration: 5 - 7 days

* Add Ampicillin 1 gm IV q6H if on TMP / SMX or Norfloxacin prophylaxis because in these cases, Streptococcus and Enterococci are more common

Esophageal Gastric Infection
Esophageal Perforation

 
Piperacillin / Tazobactam 4.5 gm IV q8H

 
Cefoperazone 1 - 2 gm IV q24H
OR Ceftriaxone 1 - 2 gm IV q24H
+
Metronidazole 500 mg IV q8H

 
 
Perforated Gastric / Duodenal Ulcers
 
Co-amoxiclav 1.2 gm IV q8H


B) Paediatrics

Disease / Etiology

Preferred

Alternative

Comments


Primary Peritonitis :
S pneumonia
Strep pyogenes
Staph aureus
Escherichia coli
Klebsiella pneumoniae

Ceftriaxone 50 mg/kg IV q12H
+
Metronidazole 7.5 mg/kg IV q8H

Piperacillin / Tazobactam 100 mg/kg (Piperacillin component) IV q6 - 8H
OR Clindamycin 10 mg/kg (max 1.2 gm) IV q6H
+
Gentamicin
1 week – 10 years old:
8 mg/kg IV q24H for Day 1 then 6 mg/kg IV q24H
> 10 years old:
7 mg/kg IV q24H for Day 1 then 5 mg/kg IV q24H
OR
Amikacin
1 week to 10 years:
25 mg/kg IV Day 1 then 18 mg/kg IV q24H
> 10 years old:
20 mg/kg IV Day 1, then 15 mg/kg (max 1.5 gm) IV q24H




Secondary Peritonitis:
E coli
Klebsiella
Enterococcus
Enterobacter
Pseudomonas
Proteus spp

Anaerobes - Bacteroides
Candida spp (rare)


Cefepime 50 mg/kg IV q12H
+
Metronidazole 7.5 mg/kg IV q8H

Piperacillin / Tazobactam 100 mg/kg (Piperacillin component) IV q6 - 8H
OR
Imipenem 15 mg/kg (max 500 mg) IV q6H
  
Peritonitis secondary to gut perforation is often polymicrobial.

Documented non-VRE and Enterococcus faecalis: Vancomycin 15 mg/kg IV q8H

Liver Abscess


Pyogenic Hepatic Abscess:
Staph aureus 
Escherichia coli
Enterococcus spp 
Klebsiella
Pseudomonas

Proteus
Bacteroides
Strep milleri


Cloxacillin 50 mg/kg IV q6H
+
Ceftriaxone 50 mg/kg IV q12H OR Ceftazidime 50 mg/kg IV q8H
+
Metronidazole 7.5 mg/kg IV q8H

 
Piperacillin/Tazobactam
100 mg/kg (Piperacillin component) IV q6-8H
 
Often associated with multiple abscesses within spleen.

Cholangitis


Escherichia coli
Klebsiella
Enterococcus
Enterobacter
Pseudomonas
Proteus

Bacteroides

Ceftriaxone 50 mg/kg IV
q12H
+
Metronidazole 7.5 mg/kg IV q8H
+
Gentamicin / Amikacin

Piperacillin / Tazobactam 100 mg/kg (Piperacillin component) IV q6 - 8H
+
Gentamicin
1 week – 10 years old:
8 mg/kg IV q24H for Day 1 then 6 mg/kg IV q24H
> 10 years old:
7 mg/kg IV q24H for Day 1 then 5 mg/kg IV q24H
OR
Amikacin
1 week to 10 years:
25 mg/kg IV Day 1 then 18 mg/kg IV q24H
> 10 years old:
20 mg/kg IV Day 1, then 15 mg/kg (max 1.5 gm) IV q24H

 

Cholecystitis

 
Escherichia coli 
Klebsiella 
Enterococcus 
Enterobacter 
Pseudomonas 
Proteus

Bacteroides
 
Ceftriaxone 50 mg/kg IV
q12H 

Metronidazole 7.5 mg/kg IV q8H 

Gentamicin / Amikacin
 
Piperacillin / Tazobactam 100 mg/kg (Piperacillin component) IV q6 - 8H 

Gentamicin 
1 week – 10 years old: 
8 mg/kg IV q24H for Day 1 then 6 mg/kg IV q24H 
> 10 years old: 
7 mg/kg IV q24H for Day 1 then 5 mg/kg IV q24H 
OR 
Amikacin 
1 week to 10 years: 
25 mg/kg IV Day 1 then 18 mg/kg IV q24H 
> 10 years old: 
20 mg/kg IV Day 1, then 15 mg/kg (max 1.5 gm) IV q24H

 
Majority are acalculous; associated with other systemic diseases like typhoid, Streptococcal infection, Staph aureus