Medical Articles
The Appendix
Anatomy & Physiology
- Length: 1-25cm (average 8cm)
- Position: Variable
- Blood supply: Appendicular artery
- Nerve supply: Autonomic nervous system
- Function: ? Immune surveilance of gut
Acute Appendicitis
INTRODUCTION
- Very common
- Lifetime risk 7%
- Peak incidence 10-30 years
- Potentially lethal condition
PATHOGENESIS
- Lumiinall obstructiion vs priimary iinffectiious etiiollogy
- Primary infectious etiology - temporall & geographiic clusteriing - Organiisms isolated → typiical coloniic flora Possible rolle off llymphoiid hyperpllasiia
- Lumiiallobstructino (most widell accepted) - lymphoid hyperplasia,, fecaliths,, increased concretions
- Obstructiion → mucous production → stasis → Bacterial overgrowth → supperation → increased intraluminal pressure → ischaemiia/inffectiion → perforatiion → localized → abscess → free → generalized periitoniitiis
CLINICAL FINDINGS
TYPICAL
- History
- Abdominal pain
- Anorexia
- Nausea & vomiting
Physical examination (varies with stage of disease progression)
- Early
- low grade fever, mild tachycardia-
- tenderness in RIF (maximal at McBurney’s point) progresses to peritoneal irritation
- Late
- free perforation → generalized peritonitis ± septic shock
- localized → appendix mass/abscess
Atypical presentation
- Atypiicall posiitiion
- Decreased iimmuniity
- Speciiffiic siigns (not so iimportant)
- Rovsiing’s siign
- Obturator siign
- Illeopsoas siign
Laboratory findings
- Raiised lleucocyte count (average 15000)
- 10% normall lleucocyte count
- ↑CRP
- Uriine
- Pregnancy test
Imaging studies
- Mostlly to excllude other pathollogiies + diiagnosiis iis uncertaiin
- Diifffferentiiate between appendiix mass + abscess
- CXR
- AXR
- Abdominalulltrasound
- AbdominalCT scan
Diagnosis + differential diagnosis
Cornerstone is history + physical examination
- Abdominal pain localising to RIF
- Anorexiia
- Nausea + vomitiing
- Low grade fever
Routine special investigations additive Special imaging studies → diagnosis in certain mass in RIF Diagnosiis uncertain → admit patiient re-evalluate 4 hrly
Differential diagnosis
Pain in RIF
- Gynaecological problems
- PID
- Ectopic pregnancy
- Ovarian pathology
- endometriosis
- Mittelschmertz
- Urinary tract pathology –
infection stones - Mesenteric lymphadenitis
- Disease of terminal ileum
- Caecal carcinoma
- Meckel’s diverticulitis
- Many other
Complications
- Perforation – localized – free
- Pylephlebitis
- Liver abscess
- Septic shock → Multi-organ failure → death (0.1%)
Treatment
- Surgical → Appendicectomy → Open → Laparoscopic
- Antibiotics – cover gram negative bacteria and anaerobes

Special subgroups
Appendix abscess + mass Abscess tends to be more tender, higher fever (typical swinging fever), higher WBC. Differentiate with ultrasound Mass → IV-antibiotics + interval appendicectomy 6 weeks later
VS
Early appendicectomy (only if experienced) Abscess → Extra peritoneal drainage of abscess (± appendectomy – only if experienced) → IV-antibiotics + interval appendicectomy 6 weeks later
Normal appendix at surgery
- Exclude other pathology
- To remove appendix or not
Post-op complications
- Early
- Wound infection
- Intra-abdominal abscess
- Leakage from appendix stump
- Late
- Adhesive band obstruction
- Infertility