Spectrum: Local Antimicrobial Stewardship, for Island Health

Appendicitis

Refers to acute inflammation and subsequent infection of the vermiform appendix

Diagnostic Pearls

Surgical consultation for all patients

Blood cultures in severely ill and health care associated complicated infections; appendectomy cultures not needed

Procalcitonin (PCT) not usually useful

Empiric Therapy

Uncomplicated

Infection not extending beyond the appendix, without perforation, phlegmon or abscess

Complicated

Presence of perforation, phlegmon or abscess

Pre-operative fecal peritonitis (free perforation)

Non-operative Management

While evidence supporting antibiotic only management of uncomplicated appendicitis is mounting, controversy exists regarding:

  • accuracy of imaging in distinguishing uncomplicated vs. complicated (perforated) disease

  • risk to elderly, immunocompromised or those with multiple co-morbidities

  • eventual need for appendectomy after > 1 year (it is currently estimated to be ~15-30% during the first year)

Non-operative management is not routinely recommended by guidelines but can be considered in select cases

For stable perforated appendicitis treated by an initial non-operative approach, see Complicated

Microbiology

Usual Organisms

Enterobacteriaceae (E. coli, Klebsiella)

Enteric anaerobes (B. fragilis, Clorstridium)

Less Common Organisms

Streptococci

Enterococcus faecalis

Organisms of Interest in IAI

ESBLs in IAI

AmpC producing organisms or "SPICE" bacteria in IAI

Enterococci, particularly E. faecium and VRE in IAI

MRSA in IAI

Candida in IAI