This document provides an overview of acute appendicitis, including its embryology, anatomy, pathophysiology, clinical presentation, diagnosis, and management. It notes that appendicitis is most commonly caused by luminal obstruction and is the most frequent abdominal surgery. Clinical diagnosis involves abdominal pain shifting to the right lower quadrant along with nausea, anorexia, and tenderness. Imaging studies like ultrasound, CT, and MRI can help diagnose appendicitis and reduce negative appendectomy rates. Treatment involves antibiotic therapy for uncomplicated cases or appendectomy, which is most often performed laparoscopically.

1. Acute Appendicitis
Dr. Raju Khatiwada
Resident
General surgery
KISTMCTH

2. CONTENTS
• Introduction
• Embryology and anatomy
• History
• Pathophysiology
• Clinical diagnosis
• Laboratory and imaging studies
• Management
• References

3. INTRODUCTION
• Most common diseases faced by the surgeon in practice.
• It is the most common urgent or emergent general surgical operation performed in
the United States and is responsible for as many as 3,00,000 hospitalizations
annually
• lifetime incidence is 8.6% in men and 6.7% in women
• Acute appendicitis is relatively rare in infants
• Incidence peaking in the second decade of life
• Appendicitis is much less common in underdeveloped countries

4. Embryology and Anatomy
• The appendix is a midgut organ and is first identified at 8 weeks of gestation as a
small outpouching of the cecum
• The appendix is a true diverticulum of the cecum as it contains all the histological
layers of the colon
• Previously considered a vestigial organ
• The appendix is now linked to the development and preservation of gut-associated
lymphoid tissue (GALT) and to the maintenance of intestinal flora

5. Embryology and
Anatomy
• During childhood, continued growth of the
caecum commonly rotates the appendix into
a retrocaecal
• In approximately one-quarter of cases,
rotation of the appendix does not occur,
resulting in a pelvic, subcaecal or paracaecal
position
• The position of the base of the appendix is
constant
Bailey and love textbook of surgery, 27th edition

6. Embryology and
Anatomy
• The average length is between 7.5 and 10 cm
• The blood supply of the appendix is
appendiceal artery, branch of ileocolic artery,
branch of the superior mesenteric artery
which courses through the mesoappendix
• Lymphatic drainage into ileocaecal lymph
nodes
Bailey and love textbook of surgery, 27th edition

7. History
• In 1735, The first appendectomy was reported by a French surgeon, Claudius
Amyand
• May 1880, The first surgeon to perform deliberate appendectomy for acute
appendicitis was Lawson Tait
• In 1886, First formal description of the disease process, was by Reginald Heber
Fitz of Harvard University.
• In 1887, Thomas Morton was the first to diagnose appendicitis,
• Charles McBurney described the clinical manifestations of acute appendicitis
including the point of maximum tenderness in the right iliac fossa

8. History
• In 1889 publication, Charles McBurney advocated for early appendectomy
• In 1894, classic muscle-splitting incision and technique for removal of the
appendix
• In 1982, First laparoscopic appendectomy by Kurt Semm

9. Pathophysiology
• Appendicitis is caused by luminal obstruction
• In pediatric populations, occurs as a result of lymphoid hyperplasia;
• In adults, it may be due to fecaliths, fibrosis, foreign bodies (food, parasites,
calculi), or neoplasia
• Intestinal parasites, particularly Oxyuris vermicularis (pinworm)
• Infections associated with appendicitis is polymicrobial
• Common isolates include Escherichia coli, Bacteroides fragilis, enterococci,
Pseudomonas aeruginosa, Klebsiella pneumoniae, and others

10. Pathophysiology
Risk factors for perforation of the appendix
• Extremes of age
• Immunosuppression
• Diabetes mellitus
• Faecolith obstruction
• Pelvic appendix
• Previous abdominal surgery

11. Clinical diagnosis (symptoms)
• Periumbilical colic
• Pain shifting to the right iliac fossa
• Anorexia
• Nausea

12. Symptoms
• The classic visceral–somatic sequence of pain is present in only about half of
those patients subsequently proven to have acute appendicitis.
• Atypical pain is more common in the elderly
• Pelvis appendix causes suprapubic discomfort and tenesmus, may be elicited only
on rectal examination
• During the first 6 hours, there is rarely any alteration in temperature or pulse rate.
• After that time, slight pyrexia (37.2–37.7ºC) with a corresponding increase in the
pulse rate to 80 or 90 is usual.
• However, in 20% of patients there is no pyrexia or tachycardia in the early stages.

13. Signs of acute appendicitis
• Pyrexia
• Localised tenderness in the right iliac fossa
• Muscle guarding
• Rebound tenderness

14. Signs to elicit in appendicitis
• Rovsing sign: the presence of right lower quadrant pain on palpation of the left
lower quadrant (normal position)
• Obturator sign: right lower quadrant pain on internal rotation of the hip (pelvic
appendix)
• Psoas sign: pain with extension of the ipsilateral hip
• Dunphy’s sign: pain with coughing (retrocecal appendix)

15. Special features, according to position of the
appendix
• Retrocaecal: Rigidity is often absent, and even application of deep pressure may
fail to elicit tenderness (silent appendix)
• Pelvic: diarrhea, absence rigidity, most common in children, rectal tenderness
present.
• Postileal: most difficult to diagnose

16. Special features, according to age
• Infant: rare, perforation
• Children: rare to find without vomiting, complete aversion to food
• Elderly: gangrene and perforation common
• Obese: diminishes all local signs
• Pregnancy:
m/c extrauterine acute abdomen
Frequency 1: 1500-2000
Diagnosis complicated by delayed presentation
Fetal loss 3-5%, 20% if perforation at operation

17. Laboratory studies
• Routine Full blood count:
leukocytosis with left shift is present in 90% of the cases
higher leukocytosis associated with gangrenous and perforated appendicitis
(∼17,000 cells/mm3)
• Urinalysis- to rule out nephrolithiasis
• Pregnancy test- mandatory in child bearing age
• Urea and electrolytes
• C-reactive protein

18. Imaging studies
• Imaging studies in patients suspected to have
acute appendicitis can reduce the negative
appendectomy rate, which can be as high as
15%
• Plain radiographs
• Ultrasound (US)
• Computed tomography (CT) scanning
• Magnetic resonance imaging (MRI)

19. USG
• Ultrasonography has a sensitivity of 0.85 (95% CI 0.79–0.90) and a specificity of
0.90 (95% CI 0.83–0.95)1
• An easily compressible appendix <5 mm in diameter generally rules out
appendicitis.
• Features on an ultrasound that suggest appendicitis include
Diameter of greater than 6 mm
Pain with compression,
Presence of an appendicolith
Increased echogenicity of the fat,
Periappendiceal fluid

20. CT-scan
• A contrast-enhanced CT scan has a sensitivity of 0.96 (95% confidence interval
[CI] 0.95–0.97) and specificity of 0.96 (95% CI 0.93–0.97)
• Features on a CT scan that suggest appendicitis include
Enlarged lumen and double wall thickness (greater than 6 mm)
Wall thickening (greater than 2 mm)
Periappendiceal fat stranding
Appendiceal wall thickening and/or
An appendicolith

21. Sabiston’s textbook of surgery-21st Edition

22. MRI
• MRI is typically reserved for use in the pregnant patient; the study is performed
without contrast agents.
• Criteria for MRI diagnosis include
Appendiceal enlargement (>7 mm),
Thickening (>2 mm), and
The presence of inflammation.
• Sensitivity of MRI to be 97% with a specificity of 95%

23. Migratory RIF pain 1
Anorexia 1
Nausea and vomiting 1
Tenderness (RIF) 2
Rebound tenderness 1
Elevated temperature 1
Leukocytosis 2
MODIFIED ALVARADO SCORE
score of 7 or more: strongly predictive of acute appendicitis.
(5–6): equivocal score

24. Modified Alvarado score
The sensitivity and specificity of the Alvarado Score and the modified Alvarado
Score have been reported to be 53–88% and 75–80% respectively
Baidya N, Rodrigues G, Rao A, et al. Evaluation of Alvarado score in acute appendicitis: a prospective study. Int
J Surg. 2007

25. Management of appendicitis
• Non-operative management
• Operative management

26. Non-operative management
• Patients with uncomplicated (absence of appendicolith, perforation or abscess)
appendicitis.
• Bowel rest and intravenous antibiotics, often metronidazole and 3rd generation
cephalosporin.
• The available data indicate initial successful outcomes in more than 90% of
patients with CT confirmed appendicitis
• However, approximately one-quarter of patients initially treated conservatively
will require surgery within 1 year for recurrent appendicitis

27. In the APPAC III trial (66 patients), 87 percent (95% CI 75-99) of those treated
with placebo and 97 percent (95% CI 92-100) of those treated with antibiotics were
successfully treated without surgery within 10 days; the difference was not
statistically significant (p = 0.142)

28. Operative management
• For open appendectomy, the patient is placed in the supine position.
• The choice of incision is a matter of the surgeon’s preference, whether it is an
Oblique muscle-splitting incision (McArthur-McBurney)
Transverse incision (Rockey-Davis) or
Conservative midline incision

29. Bailey and love textbook of surgery, 27th edition

30. Open vs Laparoscopic appendectomy
• The debate about the choice of open versus laparoscopic appendectomy for the
treatment of appendicitis was historically a major point of controversy among
surgeons.
• Although no level I data exist to support one approach over another

31. Using the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP)
database (2005-2008)

32. CONCLUSION
• The investigators observed that laparoscopic appendectomy was associated with
lower risk of wound complications and deep surgical site infection in
uncomplicated appendicitis.
• In complicated appendicitis, laparoscopic appendectomy was associated with
fewer wound complications but a slightly higher incidence of Intraabdominal
abscess.

33. Management of appendix mass
• Standard treatment is the conservative Ochsner–Sherren regimen
• Criteria for stopping conservative treatment of an appendix mass
A rising pulse rate
Increasing or spreading abdominal pain
Increasing size of the mass
• Failure of the mass to resolve should raise suspicion of a carcinoma or Crohn’s
disease.
• Using this regime, approximately 90% of cases resolve without incident.

34. Post operative complications
• Wound infection is the most common postoperative complication, occurring in 5–
10% of all patients.
• Intra-abdominal abscess: Approximately 8% of patients
• Ileus:
A period of adynamic ileus is to be expected after appendicectomy, and this may
last a number of days following removal of a gangrenous appendix.
Ileus persisting for more than 4 or 5 days, particularly in the presence of a fever, is
indicative of continuing intra-abdominal sepsis and should prompt further
investigation
• Faecal fistula: from appendicular stump, rare

35. REFERENCES
1. Keyzer C, Zalcman M et al, Comparison of US and unenhanced multi-detector
row CT in patients suspected of having acute appendicitis. Radiology. 2005
Aug;236(2):527-34. doi: 10.1148/radiol.2362040984. PMID: 16040910.
2. Bailey and love textbook of surgery, 27th edition
3. Sabiston’s textbook of surgery-21st Edition
4. Schwartz textbook of surgery, 11th edition.
5. Uptodate

36. THANK YOU!
ANY QUESTIONS?