Acute Appendicitis

SURGICAL ABDOMEN
By Heinrich
 Outline
• Definition
• Epidemiology
• Aetiology
• Risk factors
• Pathophysiology
• Clinical presentation
• Diagnosis
• Treatment/management
• Complications
• Differential diagnosis
 Definition
• Appendicitis may be defined as inflammation of the
vermiform appendix
• Acute appendicitis is a common acute surgical presentation
• It is the most common cause of acute abdomen requiring
emergency surgical intervention in both children and adults
• Uncomplicated appendicitis: appendicitis with no evidence of
an appendiceal fecalith, an appendiceal tumor, or
complications, such as perforation, gangrene, abscess, or mass
• Complicated appendicitis: appendicitis associated with
perforation, gangrene, abscess, an inflammatory mass,
an appendiceal fecalith (concretion of feces that develops in
the appendix that can obstruct the appendiceal lumen), or an
appendiceal tumor
 Chronic vs. Acute Appendicitis

• Acute appendicitis happens quickly and needs to be

treated urgently. But in some cases, the symptoms
caused by inflammation of the appendix —
especially pain in the lower right abdomen — can
last for weeks, months, or even years, subsiding on
their own and then later recurring. This is called
chronic appendicitis, and it accounts for
approximately 1.5 percent of all appendicitis cases.
 Epidemiology

• It most commonly affects those in their second or

third decade and there is an overall lifetime risk of
7-8%. It is one of the most common causes of
abdominal pain in young people and children, with
around 50,000 appendicectomies performed in
both children and adults a year in the UK
• Relative incidence is low in Africa and Asia as
compared to Europe
• In Accra the incidence is around 1 in 3333 and
account for about 30% of all surgical emergencies
 Aetiology
• Obstruction caused by
i. Appendiceal fecalith and fecal stasis (35% of
cases): most common cause in adults. Fecalith is poop
rock.
ii. undigested seeds
iii. Parasitic infestation(uncommon): pin worm
iv. Lymphoid hyperplasia (lymphoid follicles grow as a
result of viral infections and in adolescent)
v. Neoplasm  (uncommon): more likely in patients > 50
years of age
 Risk factors
• Family history
– Twin studies suggest that genetics account for 30% of
risk*
• Ethnicity/race
– More common in Caucasians
• Environmental
– Seasonal presentation during the summer
• *No specific gene has been identified specifically,
but the risk is roughly three times higher in
members of families with a positive history
 Pathophysiology
• Obstructed proximal appendiceal lumen (closed-
loop obstruction), resulting in:
– Stasis of mucosal secretions → bacterial multiplication
and local inflammation → transmural spread of infection
→ clinical features of appendicitis
– Increased intraluminal pressure → obstruction
of veins→ edema of the appendiceal walls →
obstruction of capillaries → ischemia → gangrenous
appendicitis with/without perforation
• Inflammation can spread to serosa, leading
to peritonitis
 Clinical features
• Migrating abdominal pain: most common and specific symptom
– Typically constant and rapidly worsens
– Most patients present within 48 hours of symptom onset.
– Initial diffuse periumbilical pain: caused by the irritation of the visceral
peritoneum (pain is referred to T8–T10 dermatomes)  
– Localizes to the RLQ within ∼ 12–24 hours: caused by the irritation of
the parietal peritoneum 
• Associated nonspecific symptoms
– Nausea
– Anorexia
• In up to 80% of cases
• Hamburger sign: If there is no loss of appetite, appendicitis is unlikely. [7]
– Vomiting 
– Low-grade fever
– Diarrhea 
– Constipation
 Clinical features cont…
• Clinical signs of appendicitis
– McBurney point tenderness (RLQ tenderness)
• Tenderness at the junction of the lateral third and medial two-thirds of a line drawn from the right 
anterior superior iliac spine to the umbilicus
• This point corresponds to the location of the base of the appendix.
– RLQ guarding and/or rigidity
– Rebound tenderness (Blumberg sign), especially in the RLQ
– Rovsing sign: RLQ pain elicited on deep palpation of the LLQ
– Psoas sign: can be performed in two different ways 
• Can be elicited on flexing the right hip with stretched leg against resistance
• RLQ pain may be elicited on passive extension of the right hip when the patient is positioned on their left side.
– Obturator sign: RLQ pain on passive internal rotation of the right hip with the hip and knee flexed 
– Hyperesthesia within Sherren triangle: formed by the anterior superior iliac spine, umbilicus, and 
symphysis pubis
– Lanz point tenderness: at the junction of the right third and left two-thirds of a line connecting
both the anterior superior iliac spines
– Pain in the Pouch of Douglas: pain elicited by palpating the rectouterine pouch on rectal
examination
– Baldwin sign: pain in the flank when flexing the right hip (suggests an inflamed retrocecal appendix
)
 Diagnosis
Risk stratification scores: AIRS & ALVERADOS
• Diagnostic test
1. Abdominal ultrasound
2. CT scan
3. MRI
4. Diagnostic laparoscopy

• Supportive test
1. Full blood count
2. C-reactive protein and Estimated sedimentary rate
3. Urine routine test
 Treatment
Principles
1. Admit
2. Prevent progression of disease
3. Prevent or manage complications
4. Fluid therapy
5. Antibiotic and antipyretic therapy
6. Surgical treatment
 Supportive care

• Bowel rest (NPO)

• Intravenous fluids 
• Electrolyte repletion as needed
• IV analgesics (using the pain management scale) 
• IV antiemetics as needed
• Antipyretic therapy
 Empiric antibiotic therapy for acute appendicitis 
• Indication: all patients with acute appendicitis
• Required coverage: against gram-negative and anaerobic organisms [19]
• Preoperative antibiotics for uncomplicated appendicitis: Administer one of the
following agents as prophylaxis against surgical site infection (can be discontinued
after surgery or within 24 hours) [14][19][37]
– A cephalosporin with anaerobic coverage: Cefoxitin DOSAGE OR Cefotetan DOSAGE
– Combination therapy with a first-generation cephalosporin (e.g., cefazolin DOSAGE) PLUS 
metronidazole DOSAGE [37]
– In patients allergic to penicillin/cephalosporin, administer clindamycin DOSAGE OR 
metronidazole DOSAGE PLUS one of the following: [37]
• High dose gentamicin DOSAGE
• Ciprofloxacin DOSAGE
• Nonoperative management for appendicitis (with or without interval appendectomy)
– Agents: See ''Mild or moderate infection'' in “Empiric antibiotic therapy for intraabdominal
infections.” [19]
– Duration for early uncomplicated appendicitis (not yet standardized): Consider initial parenteral 
antibiotics for at least 2–3 days then switch to oral antibiotics for 7 days.  [33][38]
– Duration for complicated appendicitis (appendiceal mass or appendiceal abscess): 3–5 days
 Operative management
Appendectomy 
• Appendectomy within 24 hours of diagnosis is the current standard of
care for acute uncomplicated appendicitis.  
• Definition: surgical removal of the appendix, usually within 24
hours of the diagnosis  
• Emergency appendectomy 
– Timing: less than 8 hours after diagnosis 
– Indications: systemic manifestations resulting from complicated appendicitis (e.g., sepsis,
generalized peritonitis) 
• Relative contraindications  
– Appendiceal mass 
– Appendicular abscess 

• Approach 
– Laparoscopic appendectomy 
– Open appendectomy (via a transabdominal incision in the RLQ) 
 Steps of nonoperative management 

• Empiric parenteral antibiotic therapy for 2–3 days: See ''Mild or

moderate infection'' under ''Community-acquired infections'' in 
empiric antibiotic therapy for intraabdominal infections. 
• Supportive care (see above)
• Periappendiceal abscess > 4 cm: image-guided percutaneous
drainage; send aspirate for cultures
• Monitor vitals and serial abdominal examinations every 6–12 hours.
– Insignificant improvement/worsening of symptoms : urgent surgical
intervention  
– Symptomatic improvement within 24–48 hours
• Slow introduction of enteral nutrition
• Switch to oral antibiotics for 7-day course.  
• Schedule interval colonoscopy in patients > 40 years of age following
NOM of acute appendicitis to rule out early colonic malignancy.
 Complications
• Inflammatory appendiceal
mass (appendiceal phlegmon) 
• Appendiceal abscess 
• Gangrenous appendicitis
• Perforated appendix
• Pylephlebitis 
• Sepsis
 Differential diagnosis
• Ectopic pregnancy
• Meckel diverticulum
• Diverticulitis(especially in elderly patients)
• Inflammatory bowel disease
• Gastroenteritis
• Colon cancer
• Urolithiasis and renal colic
• Urinary tract infections
• Psoas abscess (in patients with a positive psoas sign)
• Gynecological diseases (e.g., pelvic inflammatory
disease, ovarian cyst
 References
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