MEDICAL BIOLOGY, HUMAN ANATOMY, PHYSIOLOGY AND PATHOLOGY - Ya.I. Fedonyuk 2010

ANATOMY, PHYSIOLOGY, PATHOLOGY

CHAPTER 7. NUTRITION PROCESS AND ITS PATHOLOGY

PATHOLOGY OF THE DIGESTIVE SYSTEM

DISORDERS OF INTESTINAL DIGESTION

INTESTINAL DISEASES

4. APPENDICITIS

Appendicitis is an inflammation of the vermiform Appendix of the cecum, accompanied by a characteristic clinical syndrome. It is one of the most common Diseases of the Digestive System, frequently requiring surgical intervention. Acute and chronic forms of the disease are distinguished. People of all ages can be affected, most commonly children and adolescents.

The disease is caused by various bacterial flora, most frequently Escherichia coli, and much less commonly by Protozoa or helminths. Predisposing factors include stasis of contents within the appendix (dense contents, fruit stones, fecaliths), impaired motility or Blood supply to the appendix, and a predominantly protein-rich diet.

In cases of acute appendicitis, inflammation may affect either only the mucous membrane of the vermiform appendix or its entire wall. The following morphological forms of acute appendicitis are distinguished: 1) simple; 2) superficial; 3) destructive. Simple appendicitis develops several hours after the onset of the first clinical symptoms and is characterized by Circulatory Disorders in the appendix wall, such as capillary stasis, vascular congestion, edema, and occasionally small hemorrhages. This is followed by serous inflammation and the appearance of a mucosal destruction site known as the primary affect, which marks the onset of acute superficial appendicitis. The walls of the appendix are edematous and dull, with vessels engorged with blood. By the end of the first day, destructive appendicitis develops, which progresses through several stages. The inflammatory exudate becomes purulent and diffusely infiltrates the entire wall of the appendix—a picture characteristic of phlegmonous appendicitis. When Phlegmon is accompanied by mucosal ulceration, it is termed phlegmonous-ulcerative appendicitis. Gangrenous appendicitis is caused by the spread of inflammation to the mesoappendix, followed by Thrombosis of the appendicular artery. In this condition, the appendix is thickened, dull green in color, covered with purulent-fibrinous deposits, and contains pus in its lumen.

The most frequent complication of acute appendicitis is its perforation, leading to the subsequent development of Peritonitis. Gangrenous appendicitis may result in auto-amputation of the appendix, which also causes peritonitis. Other complications include appendiceal infiltrate, appendiceal abscess, Sepsis, and pylephlebitis (suppurative thrombophlebitis of the portal vein branches).

In chronic appendicitis, sclerotic changes are found in the wall of the vermiform appendix, along with partial or complete obliteration of its lumen and the presence of periappendiceal adhesions. Against this Background, acute flare-ups may occur, leading to phlegmon or Gangrene of the vermiform appendix.