Appendix

 

Appendix

PKGhatak, MD

Appendix means an attachment to a document. Centuries earlier when Geeks began to dissect cadavers to study human anatomy, they described a small narrow tube hanging from the cecum and called it an appendix. Appendix later received a nastier name in 1579 given by Yolanda Smith - Vermiform appendix (worm like appendix) and that name got tucked in the medical field.

 ..Before the days of general anesthesia and sterilization, infection of the appendix was bad news as bad as a death sentence. In 1735 Dr. Claudius Amyland in London, England successfully surgically removed an appendix from an 11 yr. boy who had swallowed a needle that perforated his appendix and lodged in the scrotum.

..In the Journal of Evolution Biology H.F Smith et al described that Appendix evolved twice in the animal kingdom, the latest appearance was in marsupials. The appendix has largely disappeared from the animal kingdom and now the appendix is found only in humans, primates, rabbits, prehensile tailed porcupines, flying squirrels, meadow voles and wombats.

..There are wide variations in the anatomy of the cecum and appendix in mammals – some have only multi chambered cecum and appendix and no small bowels, some have a larger appendix and small cecum, and some only appendix and no cecum.

..Human appendix in adults is about 3 inches long, attached to the far end of the cecum next to the junction of the small intestine to the cecum. The appendix is richly supplied by arterial blood. The size of the appendix is much larger in the developing fetus and continues to grow through early childhood and starts to diminish in size with the onset of sex hormones secretion.

..A microscopic look at the appendix will convince anyone that the appendix belongs to the lymphatic system. The lymph follicles of the appendix are large compared to the rest of the tissues, the follicles are many and arranged in a circle. Structurally the appendicular lymph follicles resemble Peyer's patches of the small intestine and functionally perform like the thymus gland. In fact, calling the appendix the intestinal thymus is not that far off.

In the appendix, lymph follicles contain lymphocyte B-cells and T-cells. B-cells and T-cells communicate with each other and function like T & B-cells in any other tissue. The bacterial antigen and other antigens are identified and collected by T-cells then given to B-cells. Cytokines of T-cells act on lymph follicles and produce immunoglobulin IgA. IgA is the immunological defense of the GI tract and prevents the invasion of bacteria, fungi, viruses, and toxins. IgA is also produced in the lymphatic tissues of the rest of the intestine.

.. Besides immunological functions, the appendix is the home of beneficial bacteria in the large gut. When diarrheal diseases and the use of antibiotics wipe away the gut bacteria and the overgrowth of harmful bacterial produce illness, the appendix replenishes new batches of beneficial bacteria.

..In reconstructive surgery, the appendix is utilized and fashioned as a sphincter of a newly created urinary bladder out of a section of the gut and also use appendix as the replacement part of a removed ureter.

..In earlier days the appendix of ruminant animals was considered a storehouse of fermenting bacteria and that belief led Charles Darwin to consider the human appendix as a relic of leaf-eating humans.

..The incidence of appendicitis is about 1 million a year in the USA. The mortality rate is 0.3%. Present days the diagnosis of acute appendicitis is made easier by Ultrasound studies. A swollen appendix and local peritoneal ascites (fluid collection) mean acute appendicitis. In retrocecal appendicitis or in ectopic pregnancy an MRI is referable. Elucidating one finger tenderness at the McBurney and leukocytosis with a left shift are not solely relied upon, but are important clinical findings.

A recent trend in appendicitis treatment is the use of antibiotics alone, no surgery, and careful watch provided ultrasound study does not show fluid collection.

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