Page 434 - Concise Pathology for Exam Preparation ( PDFDrive )

14 The Oral Cavity and Gastrointestinal Tract 419

• Cough, dyspnoea and wheezing (asthmatic bronchoconstrictive attack due to released mediators)
• Hepatic metastasis causing nodular liver (hepatomegaly) in some patients
• Systemic fibrosis involving heart (right-sided valvular stenosis and endocardial fibrosis),
retroperitoneal and pelvic fibrosis in other patients

Q. Describe the clinicopathological features of acute appendicitis.

Ans. Acute appendicitis is defined as acute inflammation of appendix. It is generally seen
in children and young adult and results from obstruction, which may be due to:
• Fecolith
• Tumour
• Foreign body
• Oxyuris vermicularis
• Diffuse lymphoid hyperplasia

Other Causes
• Inappropriate intake of roughage
• Haematogenous spread of infection to appendix
• Vascular occlusion
• Idiopathic

Pathogenesis (Flowchart 14.3)

Obstruction/infection causes secretion and accumulation of
mucinous fluid in the lumen

Increased intraluminal pressure

Impairs venous drainage by compressing veins

Ischaemic injury and bacterial proliferation result in further inflammation,
oedema, exudation and ischaemic injury to appendix
FLOWCHART 14.3. Pathogenesis of acute appendicitis.

Morphology
The histological hallmark for the diagnosis of acute appendicitis is neutrophilic infiltration
of the muscularis propria.

Normal Appendix
• Serosa is glistening and thin.
• No neutrophilic infiltrate observed in the muscle layer.
Acute Appendicitis
• Organ swollen with a hyperaemic, dull and granular mucosa
• Neutrophilic infiltration in mucosa, submucosa and muscularis propria
• Subserosal vessels congested
Acute Suppurative Appendicitis
• Serosa is coated with a fibrinopurulent exudate.
• Prominent ulceration and necrosis in the mucosa

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