Intestinal Obstruction, Gall Bladder & Pancreas Diseases

INTESTINAL OBSTRUCTION 1  Acute Intestinal obstruction Definition: It is sudden complete obstruction to the passage of intestinal contents. Causes: Functional obstruction Paralytic ileus Organic obstruction Simple obstr...

INTESTINAL OBSTRUCTION 1  Acute Intestinal obstruction Definition: It is sudden complete obstruction to the passage of intestinal contents. Causes: Functional obstruction Paralytic ileus Organic obstruction Simple obstruction Vascular obstruction (mesenteric artery occlusion) Strangulated obstruction 2  Intestinal obstruction Paralytic ileus: Parasympathetic inhibition by bacterial toxins in peritonitis Sympathetic stimulation by operative trauma Spinal injuries 3  Intestinal obstruction Simple obstruction: Fecolith Foreign body Gall stones Mass of Ascaris worms 4  Intestinal obstruction Vascular obstruction: Thrombosis or embolism leading to gangrene of affected segment and loss of peristalsis causing obstruction. Strangulation: Volvulus Intussusception Strangulated hernia 5  Intestinal obstruction Pathological features: Above obstruction: The intestine is distended by intestinal fluids and gases. Distension interferes with the venous drainage with congestion. This causes extravasation of blood into intestinal wall, lumen and peritoneal cavity. Bacteria penetrate intestinal wall and causes septic peritonitis. At level of obstruction: The pathology of the cause is seen. Below obstruction: The intestine is empty and collapsed 6  Acute Intestinal obstruction Complications: Repeated vomiting leading to dehydration and shock Fluid and electrolyte loss Myocardial damage from potassium loss Intestinal gangrene Septic peritonitis Toxemia 7  Chronic Intestinal obstruction Definition: It is gradual incomplete obstruction to the passage of intestinal contents. Causes: Polypoid / infiltrating carcinoma Bilharzial polyps Strictures: Ulcerative colitis, Crohn’s, TB, diverticulitis. Peritoneal adhesions External pressure: by tumor, enlarged lymph node Megacolon 8 Chronic Intestinal obstruction Pathological featurs: Above obstruction: The intestine is dilated with thick hypertrophied wall. The mucosa showed stercoral ulcers caused by retained stool. At the level of obstruction : The pathology of the cause is seen. Below obstruction: Intestine is collapsed. 9 Chronic Intestinal obstruction Complications: Vomiting Constipation Retained stool may become hard and impacted into a narrow segment leading to acute intestinal obstruction 10  Intussusception Intussusception: invagination of one segment of the intestine (intussusceptum) into the immediately distal segment (intussuscpient). Aetiology: Irregular peristalsis: Mickel’s diverticulum Polypoid tumors Bilharzial polyps Gastroenteritis Intestinal parasites Irritant foods 11  Intussusception Pathological types: Ileo-cecal intussusception (small intestine invaginate into large intestine) Enteric intussusception (small intestine invaginate into small intestine) Colonic intussusception (large intestine invaginate into large intestine) Pathology and effects : Acute intestinal obstruction 12 Intussusception 13  Volvulus Definition: Complete twisting of a bowel loop about its mesenteric base. Aetiology: The condition occurs in : Sigmoid colon due to long mesocolon and loaded sigmoid due to constipation. Ileum in Meckel’s diverticulum and peritoneal adhesions. Pathology and effects : Acute intestinal obstruction 14 Volvulus 15  Strangulated hernia Hernia : is protrusion of the contents of a sac through a defect in the wall of this sac. Aetiology of abdominal hernia: The defect may be congenital or acquired. Increased intra abdominal pressure due to ovarian tumors, repeated pregnancies or lifting heavy weights. 16 Strangulated hernia 17  Strangulated hernia Types : Internal: as hiatus hernia External: as inguinal hernia, femoral hernia, umbilical hernia and post surgical incisional hernia. Complications: Irreducibility Inflammation Obstruction Strangulation 18  Appendicitis Definition:Inflammation of the appendix. It could be acute or chronic. 19  Acute appendicitis: Causes: A) Infection: Streptococci and staphylococci are the most common causes of acute infection. B) Obstruction of appendix: Obstruction could be due to hyperplasia of lymphoid tissue, fecolith (dry fecal matter), marked fibrosis of the wall, foreign material or impacted seeds. C) Diet: Excess meat and fewer amounts of fibers in diet predispose to obstruction as meat slows peristalsis, while fibers activate peristalsis and prevents food stagnation. 20 Appendicitis 21  Types: A) Acute catarrhal appendicitis: It is the early stage of inflammation in which the appendix is congested and swollen. Microscopically, there is excess mucus in lumen, edema, and few numbers of neutrophils in mucosa and submucosa. 22 B) Acute suppurative appendicitis: The appendix is markedly swollen, with dilated vessels, ulcers, and purulent patches on the outer surface. Lumen is filled with pus. Microscopically, there is dense collection of neutrophils, congested vessels and necrosis in all layers reaching serosa and peritoneal fat. 23 C) Acute gangrenous appendicitis: Untreated cases of acute appendicitis may turn gangrenous due to thrombosis of blood vessels caused by inflammatory stasis followed by putrefaction. It starts at the tip and spreads to include the whole appendix with softening of wall and dark coloration. Perforation usually follows. Microscopically, there are massive necrosis, pus and thrombosed vessels. 24 25  Complications: 1. Perforation and peritonitis 2. Appendicular mass: The omentum is stuck by fibrinous exudates to the appendix and adjacent loops of intestine. 3. Appendicular abscess: It may open to the outside through the abdominal wall, into a loop of intestine causing fistula, or into the peritoneal cavity causing diffuse septic peritonitis. 4. Septic thrombophlebitis of appendicular vein leads to portal pyemia. 26 CANCER COLON 27  Cancer Colon Aetiology: More common in males Usually over 45 y. Younger age is seen with familial polyposis coli. Predisposing factors : Excess energy intake relative to requirements Low vegetable fiber intake High content of refined CHO High intake of red meat Adenomas (tubular, villous) Ulcerative colitis 28  Cancer Colon Pathological features: Site: Caecum and ascending colon (38%), Transverse colon(18%), descending colon (8%), rectosigmoid (35%). Grossly: Fungating (caecum and ascending colon) Infiltrating (distal colon) Malignant ulcer Mic: Adenocarcinoma, Mucoid carcinoma, Signet ring cell carcinoma, Scirrhous carcinoma 29  Cancer Colon Spread: Direct to urinary bladder, vagina, liver Lymphatic to mesenteric and para-aortic LNs Blood to liver, lungs and bones Transcoelomic leading to peritoneal deposits and hemorrhagic ascites. Complications: Spread Intestinal obstruction Bleeding per rectum and piles Fistulas between intestinal loops and urinary bladder or vagina. 30 Stage of cancer colon till till seosa serosa with no with l.n metast atic l.n 31  Familial adenomatous polyposis Familial adenomatous polyposis (FAP) is an inherited disorder characterized by cancer of the large intestine (colon) and rectum. People with the classic type of familial adenomatous polyposis may begin to develop multiple noncancerous (benign) growths (polyps) in the colon as early as their teenage years. Unless the colon is removed, these polyps will become malignant (cancerous). The average age at which an individual develops colon cancer in classic familial adenomatous polyposis is 39 years. 32 Familial adenomatous polyposis 33 Thanks 34 DISEASES OF GALL BLADDER AND PANCREAS  Acute cholecystitis ▣ Definition: Acute inflammation of the gall bladder. ▣ Aetiology: ◼ Calcular cholecystitis : 90% , due to obstruction of the cystic duct by gall stones. ◼ Non-calcular cholecystitis: 10%. It results from: Severe trauma Postoperative Sepsis Severe burns Multisystem organ failure  Acute cholecystitis ▣ Pathogenesis: ◼ In calcular cases the inflammation is initiated by: Chemical irritation of the gall bladder by bile acids and release of inflammatory mediators Gall bladder dysmotility Distension Ischemia Bacterial infection comes later ◼ In non calcular cases inflammation is resulted from ischemia  Acute cholecystitis ▣ Pathological features: ◼ Enlarged size ◼ Lumen contains turbid bile or pus ◼ Thickened edematous wall +/- microabscesses ◼ Microscopic : Lumen contains neutrophils and pus cells Ulcerated mucosa Congested edematous submucosa with neutrophiic infiltrate  Acute cholecystitis ▣ Complications: ◼ Empyema of the gall bladder ◼ Gangrene of gall bladder ◼ Perforation of gall bladder ◼ Enteric fistula formation ◼ Cholangitis ◼ Septic peritonitis ◼ Chronic cholecystitis  Chronic cholecystitis ▣ Definition: Chronic inflammation of the gall bladder ▣ Aetiology: ◼ Repeated attacks of acute cholecystitis ◼ May start as chronic ▣ Pathogenesis : ◼ Although gall stones are always present they may not play a direct role in initiation of inflammation. ◼ Chronic saturation of the bile with cholesterol permits cholesterol effusion of the wall and initiation of inflammation and gall bladder dysmotility  Chronic cholecystitis ▣ Gross: ◼ Thickened and reticulated wall ◼ Lumen contains stones ◼ Mucosal out pouchings (Rokitansky-Aschoff sinuses) ◼ Outer surface shows adhesions ◼ Enlarged cystic lymph nodes ◼ The size may be enlarged due to obstruction, normal or decreased from fibrosis with exaggeration of the mucosal folds.  Chronic cholecystitis ▣ Microscopic: ◼ Mucosa may be hyperplastic and extends deeply into submucosa and musculosa ( Cholecystitis glandularis proliferans) ◼ Mucosa may show squamous metaplasia ◼ Cholesterol laden macrophages in lamina propria (Cholesterolosis) ◼ Wall is infiltrated with chronic inflammatory cells and is fibrosed ◼ Marked histiocytic inflammation (Xanthogranulomatous cholecystitis)  Chronic cholecystitis ▣ Complications: ◼ Acute cholecystitis ◼ Formation of gall stones ◼ Carcinoma of gall bladder  Gall stones ▣ Causes ▣ Effects and complications ▣ Types of gall stones  Gall stones ▣ Aetiology: ◼ Abnormal composition of bile Excess cholesterol (Hypercholestelemia) Excess bilirubin (Hemolytic anemia) Excess calcium (Hypercalcemia) ◼ Stasis of bile : Extra hepatic biliary obstruction Pregnancy ◼ Infection: Chronic cholecystitis ▣ Gall stones are common in fatty, fertile, forty females Gall stones Gall stones Gall stones  Types of gall stones ▣ Cholesterol stone: Mammilated outer surface ▣ Pigment stone: black ▣ Mixed or infective stone: Faceted surface  Gall stones ▣ Effects and complications: ◼ Migration causes biliary colic and biliary obstruction ◼ Cholecystitis and cholangitis ◼ Obstruction of common bile duct leads to obstructive jaundice ◼ Obstruction of ampulla of Vater causes acute hemorrhagic pancreatitis ◼ Squamous metaplasia and malignancy Diseases of the pancreas  Acute pancreatitis Definition: Enzymatic necrosis and inflammation of the pancreas. Types: Acute interstitial pancreatitis Acute necrotizing (hemorrhagic) pancreatitis Bile reflux pancreatitis Acute pancreatitis  Causes and Pathogenesis of acute pancreatitis - Auto digestion by abnormal activated enzymes. - Trypsin activates digestive enzymes (Amylase and Lipase) and prekallikrien which activates clotting and complement systems and stimulates small blood vessels thrombosis. - Obstruction caused by gall stones or fibrosis caused by alcohol consumption leads to increase pancreatic ductal pressure. - Leakage of rupture of pancreatic duct well start the digestive and inflammatory process.  Acute pancreatitis - Pancreatic cell injury also caused by infections, drugs, trauma and shock. - Fat necrosis attracts neutrophils that release cytokines which cause interstitial edema and ischemia. Acute pancreatitis  Acute pancreatitis Gross: Swollen pancreas with yellow areas of fat necrosis and hemorrhagic areas. Microscopically: Diffuse interstitial edema, necrosis, neutrophils, hemorrhage and classification. Complications: - Pancreatic abscess - Pancreatic cyst - Peritonitis - Thrombosis  Chronic pancreatitis ▣ Definition: Chronic pancreatitis is a condition characterized by repeated bouts of mild to moderate pancreatic inflammation with continued loss of pancreatic parenchyma and replacement by fibrous tissue. ▣ Causes: ◼ Alcoholism ◼ Hypercalcemia ◼ Biliary tree disease ◼ Hyperlipidemia ◼ Malnutrition  Chronic pancreatitis ▣ Pathogenesis: ◼ Ductal obstruction by secretions as in alcoholism ◼ Oxidative stress from alcohol induced oxygen radical generation ◼ Interstitial fibrosis from repeated acute pancreatitis. ▣ Complications: ◼ Malabsorption ◼ Steatorrhea ◼ Diabetes mellitus ◼ Pseudocysts ◼ Obstructive jaundice  Tumors of pancreas - Tumors of exocrine pancreas - Serous and mucinous cystadenoma - Intraduct papilloma - Mature cystic teratoma - Borderline tumors - Solid cystic papillary tumor - Ductal adenocarcinoma most common - Fibroma - Lipoma - Hemangioma  Tumors of pancreas - Endocrine tumors of the pancreas - Insulinoma (Beta or "B" cells which produce insulin) - Gastrinoma (G cells which produce gastrin) - Glucagonoma (Alpha or A cells which produce glucagon) - Somatostatinoma (Delta or "D" cells which produce somatostatin). - VIPomas - Carcinoid tumors  Complications of diabetes mellitus 1. Ketosis and diabetic coma. 2. Renal complications: Pyelonephritis. Nodular glomerulosclerosis: or Kimmelstiel-Wilson disease leading to the nephrotic syndrome. Necrosis of the renal papillae. 3. Cardiovascular complications: Atherosclerosis. Hypertension. Myocardial infarction.  Complications of diabetes mellitus Gangrene of the limbs 4. Respiratory complications: Bronchitis and bronchopneumonia. Pulmonary tuberculosis. Lung abscess and gangrene. 5. Nervous system complications: Peripheral neuritis, cerebral hemorrhage, cerebral artery thrombosis and infarction. 6. Diabetic retinopathy: It appears as micro aneurysms of the capillaries of the retina. 7. Skin complications: Carbuncle and cellulitis.