Cholecystitis

Lecture 31

• Cholecystitis (Greek, -cholecyst, "gallbladder", combined with the suffix -itis, "inflammation") is inflammation of the gallbladder, which occurs most commonly due to obstruction of the cystic duct with gallstones (cholelithiasis).

Classification

• Acute: calculous & acalculous• Chronic• Acute superimposed on chronic

Acute Cholecystitis

• Acute calculous cholecystitis is an acute inflammation of the gallbladder, precipitated 90% of the time by obstruction of the neck or cystic duct.

• It is the primary complication of gallstones and the most common reason for emergency cholecystectomy.

Aacalculous cholecystitis

• Cholecystitis without gallstones called acalculous cholecystitis may occur in severely ill patients and accounts for about 10% of patients with cholecystitis.

Pathogenesis.

• Acute calculous cholecystitis results from

chemical irritation and inflammation of the obstructed gallbladder.

• The action of mucosal phospholipases hydrolyzes luminal lecithins to toxic lysolecithins.

• The normally protective glycoprotein mucus layer is disrupted, exposing the mucosal epithelium to the direct detergent action of bile salts.

• Prostaglandins released within the wall of the distended gallbladder contribute to mucosal and mural inflammation.

• Gallbladder dysmotility develops; distention and increased intraluminal pressure compromise blood flow to the mucosa.

• Acute calculous cholecystitis frequently

develops in diabetic patients who have symptomatic gallstones.

Pathogenesis

• Acute acalculous cholecystitis is thought to result from ischemia. The cystic artery is an end artery with essentially no collateral circulation.

Risk factors for acute acalculous cholecystitis include:

(1) Sepsis with hypotension and multisystem organ failure;

(2) Immunosuppression; (3) Major trauma and burns; (4) Diabetes mellitus; and (5) Infections.

Morphology.

In acute cholecystitis the gallbladder is usually enlarged and tense, and it may assume a bright red or blotchy, violaceous to green-black discoloration, imparted by subserosal hemorrhages.

• The serosal covering is frequently layered by fibrin and, in severe cases, by a definite suppurative, coagulated exudate.

Morphology

• In calculous cholecystitis, an obstructing stone is usually present in the neck of the gallbladder or the cystic duct.

• The gallbladder lumen may contain one or more stones and is filled with a cloudy or turbid bile that may contain large amounts of fibrin, pus, and hemorrhage.

• In mild cases the gallbladder wall is thickened, edematous, and hyperemic.

• In more severe cases it is transformed into a green-black necrotic organ, termed

gangrenous cholecystitis, with small-to-large perforations.

• The invasion of gas-forming organisms, notably clostridia and coliforms, may cause an acute “emphysematous” cholecystitis.

Clinical Features. • An attack of acute cholecystitis begins with

progressive right upper quadrant or epigastric pain, frequently associated with mild fever, anorexia, tachycardia, sweating, nausea, and vomiting.

• The pain may be referred pain that is felt in the right scapula rather than the right upper quadrant or epigastric region (Boas' sign).

• It may also correlate with eating greasy, fatty, or fried foods.

• The Murphy sign is specific, but not sensitive for cholecystitis.

• Elderly patients and those with diabetes may have vague symptoms that may not include fever or localized tenderness.

• More severe symptoms such as high fever, shock and jaundice indicate the development of complications such as

• abscess formation, • perforation or • ascending cholangitis.

• Another complication, gallstone ileus, occurs if the gallbladder perforates and forms a fistula with the nearby small bowel, leading to symptoms of intestinal obstruction.

• Clinical symptoms of acute acalculous cholecystitis tend to be more insidious, since symptoms are obscured by the underlying conditions precipitating the attacks.

• As a result of either delay in diagnosis or the disease itself, the incidence of gangrene and perforation is much higher in acalculous than in calculous cholecystitis.

Chronic Cholecystitis • Chronic cholecystitis may be a sequel to

repeated bouts of mild to severe acute cholecystitis,

• but in many instances it develops in the apparent absence of antecedent attacks.

• Since it is associated with cholelithiasis in more than 90% of cases, the patient populations are the same as those for gallstones.

• supersaturation of bile predisposes to both chronic inflammation and, in most instances, stone formation.

• Unlike acute calculous cholecystitis, obstruction of gallbladder outflow is not a requisite.

• , the symptoms of calculous chronic cholecystitis are biliary colic to indolent right upper quadrant pain and epigastric distress.

Morphology.

• The morphologic changes in chronic cholecystitis are extremely variable and sometimes minimal.

• The serosa is usually smooth and glistening but may be dulled by subserosal fibrosis.

• Dense fibrous adhesions

• On sectioning, the wall is variably thickened, and has an opaque gray-white appearance.

• In the uncomplicated case • the lumen contains fairly clear, green-yellow,

mucoid bile and usually stones. The mucosa itself is generally preserved.

Microscopy

• In the mildest cases, only scattered lymphocytes, plasma cells, and macrophages are found in the mucosa and in the subserosal fibrous tissue.

• In more advanced cases there is marked subepithelial and subserosal

fibrosis, accompanied by mononuclear cell infiltration.

• Outpouchings of the mucosal epithelium through the wall

(Rokitansky-Aschoff sinuses) may be quite prominent.

Acute superimposed on chroniccholecystitis

Superimposition of acute inflammatory changes implies acute exacerbation of an already chronically injured gallbladder.

Porcelain gallbladder

• In rare instances extensive dystrophic

calcification within the gallbladder wall may yield a porcelain gallbladder, notable for a markedly increased incidence of associated cancer.

• Xanthogranulomatous cholecystitis is also a rare condition in which the gallbladder has a

massively thickened wall, is shrunken, nodular, and chronically inflamed with foci of necrosis and hemorrhage.

• Finally, an atrophic, chronically obstructed gallbladder may contain only clear secretions, a condition known as

hydrops of the gallbladder.

Clinical Features.

• Usually characterized by recurrent attacks of either steady or colicky epigastric or right upper quadrant pain.

• Nausea, vomiting, and intolerance for fatty foods are frequent accompaniments.