7% lifetime risk; incid in ER pts w abdominal pain under age 60 yr = 25%, over age 60 yr = 4%
Sx:Nausea, anorexia; pain, periumbilical at 1st, then migrates to right lower quadrant; <72 h duration; sensation of constipation and urge to defecate
Si:Fever 37.5-38.5°C; <101°F. Right lower quadrant guarding and rebound tenderness; tenderness may only be on pelvic/rectal exam or w heel pounding; later rigidity and diminished bowel sounds; mass; any or all may be absent, esp in the elderly
Perforation (20-25%) w peritonitis; perforation increases prevalence of infertility × 5 (Nejm 1986;315:1506)
r/o PID; intussusception in children < age 4 yr; mesenteric adenitis including Yersiniapseudoappendicular syndrom (Yersinia Gastroenteritis) (Nejm 1989;321:16); diverticulitis; typhilitis, a cecal colitis seen w aggressive chemoRx of leukemia
Lab:
Hem:CBC not sens or specif, but usually wbc about 10 000-13 000 with some left shift
Urine:Urinalysis often shows hematuria, suggesting ureteral impingement
Xray:
(Ann IM 2004;141:537)
1st: Spiral CT after Gastrografin enema (Nejm 1998;338:141), or plain CT w rectal contrast; combined w US in children has 94% sens and specif (Jama 1999;282:1041); esp useful in women and whenever dx equivocal
2nd: Ultrasound, 25% false neg, 0% false pos? (Nejm 1987;317:666)
KUB not helpful
Rx:
Surgery; w cefoxitin prophylactically perioperatively if perforation likely? Neg pathology in 15-20% overall despite current diagnostics (Jama 2001;286:1748), and in 45% of young women
Pain meds ok to use while w/u in progress (Acad Emerg Med 1996;3:1086; BMJ 1992;305:554)