Diferencia entre revisiones de «Appendicitis»
(Major update: Alvarado/AIR scores, CODA trial antibiotics-first approach, atypical presentations (pregnancy/elderly/retrocecal), MRI in pregnancy, interval appendectomy, references with PMIDs) |
(Strip excess bold) |
||
| Línea 1: | Línea 1: | ||
==Background== | ==Background== | ||
*'''Most common surgical emergency''' worldwide | *'''Most common surgical emergency''' worldwide | ||
*Lifetime risk: | *Lifetime risk: ~7-8% (peak incidence ages 10-30) | ||
*Pathophysiology: | *Pathophysiology: luminal obstruction (fecalith, lymphoid hyperplasia, rarely tumor) → bacterial overgrowth → wall inflammation → ischemia → perforation | ||
* | *Perforation risk increases with time: ~2% at 24 hours, increasing to ~50% by 72 hours | ||
*Atypical presentations common in: children, elderly, pregnant women, immunocompromised | *Atypical presentations common in: children, elderly, pregnant women, immunocompromised | ||
==Clinical Features== | ==Clinical Features== | ||
===Classic Presentation=== | ===Classic Presentation=== | ||
* | *Periumbilical pain migrating to RLQ over 12-24 hours (migration is most specific historical feature) | ||
* | *Anorexia (nearly universal; absence should raise doubt) | ||
*Nausea, vomiting (usually after onset of pain) | *Nausea, vomiting (usually after onset of pain) | ||
*Low-grade [[fever]] (high fever suggests perforation/abscess) | *Low-grade [[fever]] (high fever suggests perforation/abscess) | ||
===Physical Exam=== | ===Physical Exam=== | ||
* | *McBurney point tenderness (1/3 distance from ASIS to umbilicus) | ||
* | *Rovsing sign: RLQ pain with LLQ palpation | ||
* | *Psoas sign: RLQ pain with right hip extension (retrocecal appendix) | ||
* | *Obturator sign: RLQ pain with internal rotation of flexed right hip (pelvic appendix) | ||
* | *Rebound tenderness and guarding (peritoneal irritation) | ||
* | *Dunphy sign: increased pain with coughing | ||
===Atypical Presentations=== | ===Atypical Presentations=== | ||
* | *Retrocecal appendix (~30%): flank or back pain, positive psoas sign, less peritoneal irritation | ||
* | *Pelvic appendix: suprapubic pain, urinary symptoms, diarrhea | ||
* | *Pregnant women: RUQ pain (displaced appendix); less peritoneal signs; higher perforation rate<ref>Mourad J, et al. Appendicitis in pregnancy: new information that contradicts long-held clinical beliefs. ''Am J Obstet Gynecol''. 2000;182(5):1027-1029. PMID 10819817</ref> | ||
* | *Elderly: delayed presentation, less fever, higher perforation rate (~50%) | ||
* | *Children <5: nonspecific symptoms; perforation common by presentation | ||
==Differential Diagnosis== | ==Differential Diagnosis== | ||
| Línea 42: | Línea 42: | ||
==Evaluation== | ==Evaluation== | ||
===Labs=== | ===Labs=== | ||
* | *WBC: elevated in ~80% (but normal WBC does NOT exclude appendicitis) | ||
* | *CRP: elevated; combined normal WBC + normal CRP has high NPV | ||
* | *Urinalysis: mild pyuria/hematuria may occur (inflammation adjacent to ureter) — does not exclude appendicitis | ||
* | *Pregnancy test in all reproductive-age women | ||
* | *Lipase if epigastric component | ||
===Clinical Decision Rules=== | ===Clinical Decision Rules=== | ||
* | *Alvarado Score (MANTRELS): Migration, Anorexia, Nausea, Tenderness RLQ, Rebound, Elevation of temp, Leukocytosis, Shift to left | ||
**Score ≤3: low risk; 4-6: moderate; ≥7: high probability | **Score ≤3: low risk; 4-6: moderate; ≥7: high probability | ||
* | *AIR Score (Appendicitis Inflammatory Response): incorporates CRP | ||
*'''These scores help risk-stratify but do NOT replace clinical judgment''' | *'''These scores help risk-stratify but do NOT replace clinical judgment''' | ||
===Imaging=== | ===Imaging=== | ||
====CT Abdomen/Pelvis with IV Contrast (Test of Choice in Adults)==== | ====CT Abdomen/Pelvis with IV Contrast (Test of Choice in Adults)==== | ||
* | *Sensitivity 94-98%, specificity 95% | ||
*Findings: enlarged appendix | *Findings: enlarged appendix > 6 mm diameter, periappendiceal fat stranding, appendicolith, wall enhancement | ||
*Signs of perforation: abscess, extraluminal air, phlegmon | *Signs of perforation: abscess, extraluminal air, phlegmon | ||
* | *Oral contrast generally NOT needed | ||
====Ultrasound (First-line in Pediatrics and Pregnancy)==== | ====Ultrasound (First-line in Pediatrics and Pregnancy)==== | ||
* | *Sensitivity 86%, specificity 81% (operator dependent) | ||
*Findings: non-compressible appendix | *Findings: non-compressible appendix > 6 mm, target sign, periappendiceal fluid | ||
* | *If US equivocal in pediatrics: MRI preferred over CT to avoid radiation | ||
====MRI (Alternative in Pregnancy)==== | ====MRI (Alternative in Pregnancy)==== | ||
* | *Sensitivity 94%, specificity 97% | ||
*Preferred over CT in pregnancy (no radiation) | *Preferred over CT in pregnancy (no radiation) | ||
| Línea 73: | Línea 73: | ||
===Uncomplicated Appendicitis=== | ===Uncomplicated Appendicitis=== | ||
*'''NPO, IV fluids, pain control''' (analgesics do NOT mask peritoneal signs) | *'''NPO, IV fluids, pain control''' (analgesics do NOT mask peritoneal signs) | ||
* | *Pre-operative antibiotics: cefoxitin 2g IV or ceftriaxone + metronidazole | ||
* | *Laparoscopic appendectomy (standard of care) | ||
* | *Antibiotics-first approach: emerging evidence supports nonoperative management with antibiotics alone for selected uncomplicated appendicitis (CODA trial)<ref>CODA Collaborative. A randomized trial comparing antibiotics with appendectomy for appendicitis. ''N Engl J Med''. 2020;383(20):1907-1919. PMID 33017106</ref> | ||
**~30% failure/recurrence rate at 1 year | **~30% failure/recurrence rate at 1 year | ||
**Shared decision-making with patient and surgeon | **Shared decision-making with patient and surgeon | ||
===Complicated Appendicitis (Perforated/Abscess)=== | ===Complicated Appendicitis (Perforated/Abscess)=== | ||
* | *Broad-spectrum antibiotics: piperacillin-tazobactam 3.375-4.5g IV OR ceftriaxone + metronidazole | ||
*Small | *Small phlegmon/abscess (<3 cm): antibiotics + interval appendectomy in 6-8 weeks | ||
* | *Large abscess (>3 cm): CT-guided percutaneous drainage + antibiotics + interval appendectomy | ||
* | *Peritonitis/sepsis: emergent appendectomy | ||
==Disposition== | ==Disposition== | ||
* | *Surgical consultation for all confirmed or highly suspected appendicitis | ||
* | *Admit for surgical management | ||
*If appendicitis suspected but imaging equivocal: | *If appendicitis suspected but imaging equivocal: observation with serial exams or repeat imaging in 6-12 hours | ||
* | *Discharge with close follow-up only if alternative diagnosis confirmed and appendicitis reliably excluded | ||
==See Also== | ==See Also== | ||
Revisión del 09:29 22 mar 2026
Background
- Most common surgical emergency worldwide
- Lifetime risk: ~7-8% (peak incidence ages 10-30)
- Pathophysiology: luminal obstruction (fecalith, lymphoid hyperplasia, rarely tumor) → bacterial overgrowth → wall inflammation → ischemia → perforation
- Perforation risk increases with time: ~2% at 24 hours, increasing to ~50% by 72 hours
- Atypical presentations common in: children, elderly, pregnant women, immunocompromised
Clinical Features
Classic Presentation
- Periumbilical pain migrating to RLQ over 12-24 hours (migration is most specific historical feature)
- Anorexia (nearly universal; absence should raise doubt)
- Nausea, vomiting (usually after onset of pain)
- Low-grade fever (high fever suggests perforation/abscess)
Physical Exam
- McBurney point tenderness (1/3 distance from ASIS to umbilicus)
- Rovsing sign: RLQ pain with LLQ palpation
- Psoas sign: RLQ pain with right hip extension (retrocecal appendix)
- Obturator sign: RLQ pain with internal rotation of flexed right hip (pelvic appendix)
- Rebound tenderness and guarding (peritoneal irritation)
- Dunphy sign: increased pain with coughing
Atypical Presentations
- Retrocecal appendix (~30%): flank or back pain, positive psoas sign, less peritoneal irritation
- Pelvic appendix: suprapubic pain, urinary symptoms, diarrhea
- Pregnant women: RUQ pain (displaced appendix); less peritoneal signs; higher perforation rate[1]
- Elderly: delayed presentation, less fever, higher perforation rate (~50%)
- Children <5: nonspecific symptoms; perforation common by presentation
Differential Diagnosis
- Mesenteric adenitis (children — viral)
- Ovarian torsion, ruptured ovarian cyst, ectopic pregnancy
- Crohn's disease (terminal ileitis)
- Diverticulitis (right-sided in Asian patients, cecal)
- Cholecystitis, nephrolithiasis, UTI
- Pelvic inflammatory disease
- Epiploic appendagitis, omental infarction
- Testicular torsion
Evaluation
Labs
- WBC: elevated in ~80% (but normal WBC does NOT exclude appendicitis)
- CRP: elevated; combined normal WBC + normal CRP has high NPV
- Urinalysis: mild pyuria/hematuria may occur (inflammation adjacent to ureter) — does not exclude appendicitis
- Pregnancy test in all reproductive-age women
- Lipase if epigastric component
Clinical Decision Rules
- Alvarado Score (MANTRELS): Migration, Anorexia, Nausea, Tenderness RLQ, Rebound, Elevation of temp, Leukocytosis, Shift to left
- Score ≤3: low risk; 4-6: moderate; ≥7: high probability
- AIR Score (Appendicitis Inflammatory Response): incorporates CRP
- These scores help risk-stratify but do NOT replace clinical judgment
Imaging
CT Abdomen/Pelvis with IV Contrast (Test of Choice in Adults)
- Sensitivity 94-98%, specificity 95%
- Findings: enlarged appendix > 6 mm diameter, periappendiceal fat stranding, appendicolith, wall enhancement
- Signs of perforation: abscess, extraluminal air, phlegmon
- Oral contrast generally NOT needed
Ultrasound (First-line in Pediatrics and Pregnancy)
- Sensitivity 86%, specificity 81% (operator dependent)
- Findings: non-compressible appendix > 6 mm, target sign, periappendiceal fluid
- If US equivocal in pediatrics: MRI preferred over CT to avoid radiation
MRI (Alternative in Pregnancy)
- Sensitivity 94%, specificity 97%
- Preferred over CT in pregnancy (no radiation)
Management
Uncomplicated Appendicitis
- NPO, IV fluids, pain control (analgesics do NOT mask peritoneal signs)
- Pre-operative antibiotics: cefoxitin 2g IV or ceftriaxone + metronidazole
- Laparoscopic appendectomy (standard of care)
- Antibiotics-first approach: emerging evidence supports nonoperative management with antibiotics alone for selected uncomplicated appendicitis (CODA trial)[2]
- ~30% failure/recurrence rate at 1 year
- Shared decision-making with patient and surgeon
Complicated Appendicitis (Perforated/Abscess)
- Broad-spectrum antibiotics: piperacillin-tazobactam 3.375-4.5g IV OR ceftriaxone + metronidazole
- Small phlegmon/abscess (<3 cm): antibiotics + interval appendectomy in 6-8 weeks
- Large abscess (>3 cm): CT-guided percutaneous drainage + antibiotics + interval appendectomy
- Peritonitis/sepsis: emergent appendectomy
Disposition
- Surgical consultation for all confirmed or highly suspected appendicitis
- Admit for surgical management
- If appendicitis suspected but imaging equivocal: observation with serial exams or repeat imaging in 6-12 hours
- Discharge with close follow-up only if alternative diagnosis confirmed and appendicitis reliably excluded
See Also
References
- ↑ Mourad J, et al. Appendicitis in pregnancy: new information that contradicts long-held clinical beliefs. Am J Obstet Gynecol. 2000;182(5):1027-1029. PMID 10819817
- ↑ CODA Collaborative. A randomized trial comparing antibiotics with appendectomy for appendicitis. N Engl J Med. 2020;383(20):1907-1919. PMID 33017106
- Di Saverio S, et al. Diagnosis and treatment of acute appendicitis: 2020 update of the WSES Jerusalem guidelines. World J Emerg Surg. 2020;15:27. PMID 32295644
- Bhangu A, et al. Acute appendicitis: modern understanding of pathogenesis, diagnosis, and management. Lancet. 2015;386(10000):1278-1287. PMID 26460662
- Alvarado A. A practical score for the early diagnosis of acute appendicitis. Ann Emerg Med. 1986;15(5):557-564. PMID 3963537