Appendicitis

For pediatric patients see Appendicitis (peds)

Background

• Most common nonobstetric surgical emergency in pregnancy
• Most commonly caused by luminal obstruction by a fecalith
• There are no historical or physical exam findings that can definitively rule out appy

Clinical Features

History

• Early on primarily malaise, indigestion, anorexia
  • Later patient develops abdominal pain
    • Initially vague, periumbilical (visceral innervation)
    • Later migrates to McBurney point (parietal innervation)
• Nausea, with or with out emesis, typically follows onset of pain
• Fever may or not occur
• Urinary symptoms common given proximity of appendix to urinary tract (sterile pyuria)
• Sudden improvement suggests perforation
• 33% of patients have atypical presentation
  • Retrocecal appendix can cause flank or pelvic pain
  • Gravid uterus sometimes displaces appendix superiorly → RUQ pain

Physical Exam

• Rovsing sign (palpation of LLQ worsens RLQ pain)
• Psoas sign (extension of right leg at hip while patient lies on left side elicits abdominal pain)
• Obturator sign (internal and external rotation of thigh at hip elicits pain
• Peritonitis suggested by:
  • Right heel strike elicits pain
  • Guarding

Clinical Examination Operating Characteristics

Procedure	LR+	LR-
RLQ pain	7.3-8.4	0-0.28
Rigidity	3.76	0.82
Migration	3.18	0.50
Pain before vomiting	2.76	NA
Psoas sign	2.38	0.90
Fever	1.94	0.58
Rebound	1.1-6.3	0-0.86
Guarding	1.65-1.78	0-0.54
No similar pain previously	1.5	0.32
Anorexia	1.27	0.64
Nausea	0.69-1.2	0.70-0.84
Vomiting	0.92	1.12

Differential Diagnosis

RLQ Pain

• Appendicitis
• Abdominal aortic aneurysm
• Crohn's disease (terminal ileitis)
• Diverticulitis (cecal, Asian patients)
• Ectopic
• Endometriosis
• Epiploic appendagitis
• Herpes zoster
• Inguinal hernia
• Ischemic colitis
• Meckel's diverticulum
• Mesenteric lymphadenitis
• Mittelschmerz
• Ovarian cyst
• Ovarian torsion
• PID
• Psoas abscess
• Testicular torsion
• Kidney stone
• Neutropenic enterocolitis (typhlitis)

Evaluation

Labs

• CBC
  • Normal WBC does not rule-out appy
• Urinalysis
  • Sterile pyuria or hematuria consistent with appy
• Urine pregnancy
• CRP
  • Normal CRP AND WBC makes appy very unlikely

Imaging

• Early surgical consultation should be obtained before imaging in straightforward cases
• Not universally necessary; consider in:
  • Women of reproductive age
  • Men with equivocal presentation
• Perforation may result in false negative study
• Modalities
  • Ultrasound
    • First choice for pregnant women and children
    • Findings: noncompressible appendix >6mm in diameter, wall thickness greater or equal to 3 mm
    • Other supportive findings: aperistalsis, distinct wall layers, target appearance in axial view, appendicolith, periappendiceal fluid, prominent echogenic periappendiceal fat
  • CT
    • First choice for adult males and nonpregnant women with equivocal cases
    • Women derive the greatest benefit from preoperative imaging (lower neg appy rate)
    • Contrast (both PO and IV) is unnecessary but typically ordered
  • MRI
    • When unable to identify appendix in children or pregnant women

Clinical Scoring Systems

Alvarado score

Right Lower Quadrant Tenderness	+2
Elevated Temperature (37.3°C or 99.1°F)	+1
Rebound Tenderness	+1
Migration of Pain to the Right Lower Quadrant	+1
Anorexia	+1
Nausea or Vomiting	+1
Leukocytosis > 10,000	+2
Leukocyte Left Shift	+1

Clinical scoring system, where a score (Total=10) is composed on presence/absence of 3 signs, 3 symptoms and 2 lab values to help guide in case management.

• ≤3 = Appendicitis unlikely
• ≥7 = Surgical consultation
• 4-6 = Consider CT

MANTRELS Mnemonic: Migration to the right iliac fossa, Anorexia, Nausea/Vomiting, Tenderness in the right iliac fossa, Rebound pain, Elevated temperature (fever), Leukocytosis, and Shift of leukocytes to the left (factors listed in the same order as presented above).

Management

Supportive Management

1. NPO status
2. Fluid resuscitation
3. Analgesia/antiemetics

Antibiotics

Coverage should extend to E. coli, Klebsiella, Proteus, and Bacteroides (an anaerobe)

Adult Simple Appendicitis

Antibiotic prophylaxis should be coordinated with surgical consult

Options:

• Cefoxitin 2g IV q6 hours OR
• Cefotetan 2g IV q12 hours OR
• Moxifloxacin 400mg IV once daily OR
• Ertapenem 1g IV once daily

Pediatric Simple Appendicitis

Options:

• Cefoxitin 40mg/kg IV q6 hours
• Cefotetan 40mg/kg IV q12 hours
• Gentamicin 2.5mg/kg IV q8hrs +
  • Metronidazole 7.5mg/kg IV 16hrs OR
  • Clindamycin 10mg/kg IV q8hrs

Complicated Appendicitis

Defined as perforation, abscess, or phlegmon

Options:

• Metronidazole 50mg IV q8hrs +
  • Cefepime 50mg/kg IV q12hrs OR
  • Ciprofloxacin 400mg IV q12hrs OR
  • Levofloxacin 750mg IV q24hrs OR
  • Aztreonam 30mg/kg IV q8hrs
• Imipenem/Cilastatin 25mg/kg IV q6hrs (max 500mg)
• Meropenem 20mg/kg IV q8hrs (max 1g)
• Piperacillin/Tazobactam 100mg/kg (max 4.5g) IV q8hrs

Cautious use should be applied to use of fluoroquinolones in complicated pediatric appendicitis due to the risk of tendon injury

Surgery

• Open laparotomy or laparoscopy
  • Patients who present <72 hours after the onset of symptoms usually undergo immediate appendectomy
  • Patients who present >72hrs and have perforated appendix may be treated initially with antibiotics, intravenous fluids, and bowel rest

Disposition

Admission for surgery

Complications

• Infection (either a simple wound infection or an intraabdominal abscess)
  • Typically in patients with perforated appendicitis

See Also

• Appendicitis (Peds)

External Links

• CHOP Appendicitis Pathway

References

Authors

Jordan Swartz, Manpreet Singh, Ross Donaldson, Bobak Zonnoor, Daniel Eggeman, Yos Yachivev, Kevin Lu, Marissa Camilon, Neil Young, Michael Hwang, Claire, Daniel Ostermayer, Michael Holtz