Download Module 5: Stewardship in intra

Objectives
 Review basic categories of intra-abdominal infection and their
respective treatments
 Community acquired intra-abdominal infection
 Mild/Moderate
 Severe
 Acute biliary tract infections
 Nosocomial intra-abdominal infection
 Consider other abdominal processes associated with antibiotic
use
 Spontaneous bacterial peritonitis
 Pancreatitis with and without necrosis
 Infectious diarrhea
 Mention of prevention of surgical infections during colorectal
surgery
Useful guidelines
1. IDSA complicated intra-abdominal infection guideline1
2. IDSA infectious diarrhea guideline2
3. AASLD ascites guidelines3
4. ACG pancreatitis guideline4
5. IDSA SHEA surgical prophylaxis guideline5
6. ISPD peritoneal dialysis infection guideline6
7. AGA diverticulitis guidelines11,12
Intra-abdominal infection
 Enteric contents enter the peritoneal cavity leading to abscess
or peritonitis
 Obtaining adequate early source control is the rule
 Localized- Appendicitis, diverticulitis, cholecystitis with or
without perforation
 Contained perforation without hemodynamic instability
 Carefully selected patients with appendiceal perforation
OCCASIONALLY treated medically without an open or
percutaneous source control procedure
 Trend to non-operative management of perforated diverticulitis
utilizing percutaneous drainage only
 Diffuse peritonitis- after perforation
 THESE PATIENTS ARE SICK AND NEED TO GO TO THE OR
“High risk” infection1
Treatment
 Mild-moderate severity: perforated appendicitis,
diverticulitis, intra-abdominal abscess.
 Cefazolin 1-2g iv q8h plus metronidazole 500mg iv q8h
 High-risk severity: hemodynamic instability, advanced
age, immune-compromised state (Table 1 on prior slide)
 Piperacillin/tazobactam 3.375g iv q8h over 4h, or
 Cefepime 1g iv q8h plus metronidazole 500mg iv q8h
 Healthcare-associated
 Use high-risk regimen
 Can consider empiric addition of vancomycin but rarely
needed
Metronidazole dosing
 T1/2 = 8h (similar to ceftriaxone)
 Concentration dependent killing
 Some institutions use q24h dosing when using IV
 1g – 1.5g IV q24h in adults1,7
 30 mg/kg/day IV q24h in children8
 When given PO, nausea is limiting so q8h dosing more
appropriate
Basic points
 Cultures not mandatory for mild-moderate infections
 Do not use ampicillin/sulbactam, clindamycin, aminoglycosides,
or cephamycins
 Empiric enterococcus therapy not needed for mild-moderate
infections but favored for severe infections
 If recovered in culture in severe or healthcare associated infection
then treat
 Empiric antifungal therapy is not recommended
 Give fluconazole if recovered in culture until identified
 Patients to be treated non-operatively for low-risk infections
should be on a low-risk regimen with plans for early PO
conversion
Biliary infections
 These are UPPER GI flora
 No anaerobic coverage required for non-severe disease
unless pre-existing biliary-enteric anastomosis is present
 Mild-moderate
 Cefazolin
 Severe
 Piperacillin-tazobactam, or
 Cefepime plus metronidazole
De-escalation and alteration of
initial regimen
 Low-risk patients with adequate source control who are
improving nicely DON’T have to be broadened if
untreated pathogens are later reported in culture
 In high risk or persistently ill patients, try to optimize
regimen to predominant flora and generally avoid
narrowing
Duration of therapy
 Stomach or proximal jejunal perforation repaired within 24h and with
adequate source control
 Cefazolin prophylaxis x24h then discontinue
 If on PPI or malignancy, give high-risk regimen x4-7d
 Penetrating/blunt or iatrogenic perforation repaired within 12 hours
 Treat for ≤24h
 Acute appendicitis without perforation
 Treat ≤24h
 Acute cholecystitis without perforation
 Treat ≤24h
 Complicated established infection with adequate source control
 4 – 7 days
Recent duration of
therapy literature
 Acute grade II cholecystitis9
 WBC >18, Mass in RUQ, >72h symptoms, or
gangrenous/pericholecystic abscess/emphysematous/local
peritonitis
 ≤4 days of therapy was as effective as >4 days Rx
 STOP-IT trial10
 NEJM 2015
 518 patients with complicated intra-abdominal infection
 Randomized to fixed 4 day Rx vs. 10 days or “clinical
resolution”
 Results: intervention group got 4 days, control 8 days
 Equivalent 21% recurrence rates
Acute uncomplicated diverticulitis
 Antibiotics may not be needed after all!?
 If no perforation or sepsis
 AGA guidelines allow for “selective” use11,12
 Several new studies show no difference in acute
resolution, possible reduced recurrence with antibiotics1316
 Too early to know what to recommend, but argues for
less-aggressive trend to current approach
Approach to perforated
diverticular abscess
 Patients with diffuse fecal peritonitis require emergent
surgery
 Localized small abscesses <4-6cm may be amenable to
antimicrobial therapy alone17,18
 Larger abscesses are generally drained by CT guidance
percutaneously
 Failure to improve with medical or CT drainage after 3
days suggests need for surgery
 Patients with successful drainage may require delayed
elective sigmoid resection due to high recurrence rates19-22
3
Spontaneous bacterial peritonitis
 Defined as PMN ≥250 cells/mm3 in ascitic fluid of cirrhotic patient with
signs or symptoms suggestive of ascitic fluid infection
 Tap and treat if PMN criteria reached
 Ceftriaxone 1g iv q12h x5 days
 Narrow if a single pathogen is isolated in culture
 Cefotaxime E. coli activity is inferior to ceftriaxone at our institutions
so no longer recommended
 Total daily dose 2g vs. 1g associated with improved outcomes29
 Give SBP prophylaxis in patients with variceal bleeding
 Ceftriaxone 1g IV q24h x 7 days
 Secondary prophylaxis after 1st SBP episode30 if ascites protein <1
 Trimethoprim/sulfamethoxazole DS 1 tab daily
 Daily ciprofloxacin 500mg PO daily if tmp/smx not feasible
Acute pancreatitis
 These patients have high WBC, fever, and tachycardia;
they look septic
 Patients with shock need blood cultures and antibiotics4
 Without shock, treat as pancreatitis with fluids, NPO etc
 If antibiotics started, when blood negative and no other
source found abx should be discontinued
 Necrotic pancreatitis is not an indication for antibiotics
 Earlier trials of PROPHYLACTIC antibiotics23,24 have been
disproven25-27
 No decrease in infections or sugery, but more RESISTANT
organisms when infection develops25
Infected pancreatic necrosis
 Patients failing to improve or worsening after 7-10 days of
conservative management
 CT guided fine needle aspiration (FNA) can be used to
diagnose
 Preferred from stewardship standpoint over empiric abx
 Prolonged IV antibiotics if infected
 Surgery can be avoided in ~3/4 of patients and only ~1/3
required percutaneous drainage28
 Cephalosporin plus metronidazole or carbapenem
Infectious Diarrhea2
 Fever and blood = dysentery
 Shigella, campylobacter, sometimes salmonella
 Await stool culture if stable
 If septic can give azithromycin 500mg or Cipro 500mg
 Traveler’s diarrhea
 Entero-toxigenic E. coli (ETEC), shigella, salmonella
 Empiric cipro 500 bid x3d or 750 x1; azithromycin 500 x3d
 Blood and NO fever
 Enterohemorrhagic E. coli (EHEC): NO ANTIBIOTICS
 Recent hospitalization, ED visit, or antibiotics
 CDIFF, CDIFF, CDIFF
Peri-operative prophylaxis for
colorectal surgery
 Our protocols mimic our treatment guidelines
 Cefazolin 2g (3g if >120kg) plus metronidazole 500mg
 Immediately prior to incision
 Can be mixed and given in same bag as “cefanidazole”
 Cefazolin redosing interval 4h; metronidazole not redosed
 Levofloxacin 750mg plus metronidazole if anaphylactic
penicillin allergy
 No redosing
 If known MRSA colonized can consider adding vancomycin
though literature supports primarily for orthopedic and cardiac
surgery
If already on antibiotics and
going to OR
 Redose based on published intra-operative redosing
interval5
 4h for cefazolin
 2h for piperacillin/tazobactam
 Using cefazolin/metronidazole is effective, easy, and
logistically simple vs. alternative regimens
 We do NOT endorse use of ertapenem for prophylaxis
 Extremely broad , ESBL coverage
 If surgeons insist on q24h regimen can use daily dosed
ceftriaxone plus metronidazole 1g
References
1.
Clinical Infectious Diseases 2010; 50:133–64
12.
Gastroenterology 2015;149:1950–1976
2.
Clinical Infectious Diseases 2001; 32:331–50
13.
Colorectal Dis. 2016 Apr 18
3.
Hepatology 2009;49:2087-107).
14.
Gastroenterology 2015;149:1650–1651
4.
Am J Gastroenterol 2013; 108:1400–1415;
15.
Br J Surg 2012;99:532–539.
5.
Am J Health-Syst Pharm. 2013; 70:195-283
16.
United European Gastroenterol J
2014;2(1S):A2
6.
Peritoneal Dialysis International, Vol. 25, pp.
107–131
17.
Tech Coloproctol. 2015 Feb;19(2):97-103
7.
J Chemother. 2007 Aug;19(4):410-6
18.
Dis Colon Rectum. 2006 Oct;49(10):1533-8
8.
J Pediatr Surg . 2008 June ; 43(6): 981–985
19.
Dis Colon Rectum. 2016 Mar;59(3):208-15
9.
J Gastrointest Surg (2013) 17:1947–1952
20.
ANZ J Surg. 2016 Apr 8.
10.
N Engl J Med 2015;372:1996-2005.
21.
Ann Surg. 2015 Dec;262(6):1046-53
11.
Gastroenterology 2015;149:1944–1949
22.
Dis Colon Rectum. 2014 Dec;57(12):1430-40
References
23.
Surg Gynecol Obstet 1993 ; 176 : 480 – 3
24.
Lancet 1995 ; 346 : 663 – 7
25.
Ann Surg 2007 ; 245 : 674 – 83
26.
Cochrane Database Syst Rev : CD002941
27.
Am J Surg 2009 ; 197 : 806 – 13
28.
Gastroenterology 2013 ; 144 : 333 – 40
29.
F1000Research 2014, 3:57
30.
Ann Pharmacother. 2010
Dec;44(12):1946-54