intra abdominal infections

uncomplicated IAI

infection remains contained within an organ

complicated IAI

infection extends beyond a single organ, involves anatomical disruption

peritonitis or abscess

peritonitis

inflammation or infection of peritoneal lining

abscess

contained, walled-off, purulent fluid collection

collection of bacteria, WBCs, necrotic debris

primary peritonitis (aka spontaneous bacterial peritonitis (SBP))

infection of peritoneal cavity without any obvious source of infection

secondary peritonitis

infection of the peritoneal cavity caused by another infectious process within the abdomen

obvious source

ex: appendicitis

tertiary peritonitis

infection of peritoneal cavity that recurs or persists > 48 hours after apparent control of primary or secondary peritonitis

peritoneal space

bottom of diaphragm to pelvic floor

retroperitoneal space

behind the peritoneum

diverticulosis

chronic

development of small pockets in wall of colon

diverticulitis

acute inflammation of diverticula commonly caused by infection

cholecystitis

inflammation of gallbladder

cholangitis

inflammation and infection of bile duct

is primary peritonitis mono or polymicrobial? what pathogens cause it?

monomicrobial

pathogens:

-cirrhosis (SBP): e coli, klebsiella, s pneumoniae, h influenzae

-peritoneal dialysis (PD): staph, strep, enterococci, e coli, pseudomonas, klebsiella

is secondary peritonitis mono or polymicrobial? what pathogens cause it?

polymicrobial

pathogens:

-gram negatives: e coli, enterobacter, klebsiella, proteus

-gram positives: cocci

-anaerobes: bacteroides, clostridium

-fungi: candida

what lab values indicate primary peritonitis?

ascitic fluid contains > 250 PMN/mm³

who is generally sicker, someone with primary or secondary peritonitis?

secondary

goals of treatment for IAI

eradicate infection

correct causative disease process or injury

prevent spread of infection

reduce or minimize occurrence of complications

surgical source control is almost always necessary for _________

secondary peritonitis (complicated IAIs)

surgical management is mainstay of _________ treatment

uncomplicated IAI treatment

primary peritonitis is often managed with _______

antibiotics

pharm treatment of IAI routes of administration

start IV

convert to PO when pt improving

who should get empiric enterococcal coverage?

high-risk pts

is empiric MRSA coverage typically recommended?

NO

antifungal therapy is indicated for higher-risk patients with IAI if _________ is grown from an intraabdominal culture

candida spp

treatment of cirrhosis/ascites (SBP)

IV 3rd gen cephalosporin

-ceftriaxone

-cefotaxime

prophylaxis of cirrhosis/ascites (SBP)

PO cipro

IV ceftriaxone

when is the intraperitoneal route preferred?

peritoneal dialysis

peritoneal dialysis (PD) treatment

one gram positive and one gram negative coverage

-gram+: first gen cephalosporin (cefazolin), vanco (if MRSA suspected)

-gram-: ceftazidime, aminoglycoside

or

4th gen cephalosporin mono therapy (cefepime)

secondary peritonitis (complicated IAI)

low risk

treatment

ceftriaxone (or cefotaxime) + metronidazole

ertapenem

cipro + metronidazole

moxifloxacin

secondary peritonitis (complicated IAI)

high risk

treatment

cefepime + metronidazole

zosyn (piperacillin/tazobactam)

acute uncomplicated appendicitis

treatment

appendectomy

acute complicated appendicitis

treatment

same as complicated IAI recommendations

carbapenem if no surgery

chronic appendicitis

treatment

antibiotics NOT recommended

NOT infectious

biliary infections

community-acquired

mild severity (grade I)

cefazolin, cefuroxime, ceftriaxone, cefotaxime ± metronidazole

cefoxitin

ertapenem

cipro or levo ± metronidazole

moxifloxacin

biliary infections

community-acquired

moderate severity (grade II)

piperacillin/tazobactam (zosyn)

ceftriazone, ceftazidime, cefepime ± metronidazole

ertapenem

cipro or levo ± metronidazole

moxifloxacin

biliary infections

community-acquired

high severity (grade III)

OR healthcare associated

vanco PLUS

-piperacillin/tazobactam (zosyn)

-ceftazidime or cefepime ± metronidazole

-imipenem/cilastatin, meropenem, or ertapenem

-aztreonam ± metronidazole

diverticulitis

community-acquired

mild-moderate/low risk

piperacillin/tazobactam (zosyn)

cefazolin, cefuroxim, ceftriaxone, or cefotaxime + metronidazole

cipro or levo + metronidazole

diverticulitis

community-acquired

severe/high risk

piperacillin/tazobactam (zosyn)

meropenem or imipenem/cilastatin

ceftazidime or cefepime + metronidazole

diverticulitis

healthcare associated

piperacillin/tazobactam (zosyn)

meropenem or imipenem/cilastatin

ceftazidime or cefepime + metronidazole ± ampicillin or vanco (if enterococcal risk)

complicated IAI with adequate source control duration of treatment

4 days

extend to 8 if critically ill

uncomplicated IAI duration of treatment

ex: traumatic bowel perforation, acute or gangrenous appendicitis, acute or gangrenous cholecystitis

24 hours

peritoneal dialysis related infection duration of treatment

14-28 days

is routine empiric coverage against fungi in IAI recommended?

NO

when is antifungal therapy indicated? what treatment is recommended?

indicated for high-risk pts with IAI if candida spp is grown

echinocandins (anidulafungin) is recommended

when is intraperitoneal route preferred over IV therapy?

when the cause of primary peritonitis is peritoneal dialysis