Appendicitis

Overview

Appendicitis can be broken down into appendi-citis, meaning inflammation of the appendix. It is one of the core surgical conditions, with an appendectomy being on of the cornerstone surgical operations. This typically presents in young males (although can be any age) with central abdominal pain progressing to sharp RIF pain. In males CT is the investigation of choice with PUSS first choice in females. Management options include appendectomy (open or laparoscopic) or antibiotics. 

Key Points

1. Inflammation of appendix, caused by infected faecolith

2. Presentation is of any age with central dull abdominal pain progressing to sharp RIF pain

3. Investigations in females US with CT or diagnostic laparotomy in males

4. Traditional management is appendectomy with a course of antibiotics and no follow up

Physiology

The appendix is located at the proximal caecum, at the beginning of the large bowel. The appendix was traditionally viewed as an evolutionary remnant with no modern day function. This has recently been contested:

1. The appendix holds a large number of immune cells and is thought to play a role in the intestinal immune system.

2. The appendix's microbiome is different to the rest of the gut microbiome and is currently thought to act as reservoir for flora bacteria that can be released in time of illness.

3. The appendix has developed within independent evolutionary trees. The fact it has not only persisted after any obvious function but been independently developed in other species suggests it does have a function. 

4. The appendix is cite of notable pathology: appendicitis and potentially an increased risk of lymphoma. 

5. Appendectomy has been linked to the development of Parkinson's Disease 

References 1-3. 

Management

The traditional management of appendicitis in the UK has been appendectomy

There has been a relatively recent re-evaluation of the requirement for a full appendectomy and whether appendicitis can be managed with an oral course of antibiotics and discharge from hospital. This idea has come from continental Europe, where medical management of appendicitis with antibiotics is more common. 

Deeper Dive

Summary of current debates:

1. Antibiotics vs Appendectomy in management of unperforated appendicitis

2. Physiologic function of the appendix

Resources and References

1. Heather F. Smith, William Parker, Sanet H. Kotzé, Michel Laurin. Morphological evolution of the mammalian cecum and cecal appendix. Comptes Rendus Palevol, 2017; 16 (1): 39 DOI: 10.1016/j.crpv.2016.06.001

2. Vitetta L, Vitetta G, Hall S. The Brain-Intestinal Mucosa-Appendix- Microbiome-Brain Loop. Diseases. 2018;6(2):23. Published 2018 Apr 1. doi:10.3390/diseases6020023  

3. Miyazaki T, Ishiguro T, Ishibashi K, Itoyama S, Ishida H. Mucosa-associated lymphoid tissue lymphoma of the appendix vermiformis. Int Surg. 2010 Jan-Mar;95(1):27-32. PMID: 20480837. 

Links

• Body system: gastrointestinal

• Specialty: general surgery

Written in 2025