Cholecystisis
Cholecystisis which is the inflammation of the Gallbladder can be Acute or Chronic
Acute Cholecystisis
Acute Cholecystisis is inflammation of the gallbladder that develops over hours, usually as results of cystic duct obstruction by a gallstone. Symptoms include right upper quadrant pain and tenderness, sometimes accompanied by fever,chills,nausea and vomiting.
Abnominal ultrasound detects the gallstone and sometimes the associated inflammation.
Treatment usually involves antibiotics and cholecytectomy.
Acute cholecystitis is the most common complication of cholelithiasis. Conversly, >= 95% of patients with acute cholecystitis have cholelithiasis.
When a stone becomes impacted in the cystic duct and causes persistent obstruction, acute inflamation results.
Bile stasis releases inflammatory enzymes (e.g phospholipase A,converting lecithin to lysolecithin which may mediate inflammation).
The damaged mucosa secretes more fluid into the gallbladder. The resulting distention releases more inflammatory mediators (e.g prostaglandins), worsening mucosal damage and causing ischemia, which perpetuates inflammation.
Bacterial infection can develop and necrosis and perforation can occur. If resolution occurs the gallbladder becomes fibrotic and contracted and fails to concentrate bile or to empty properly .
Acute acalculous cholecystitis (i.e cholecystitis without stones) accounts for 5 to 10% of cholecystectomies performed for acute cholecystitis. Risk factors include critical illness (often surgery,burns,sepsis, or major trauma), prolonged fasting or TPN ( which predispose to bile stasis), shock and vasculitis (e.g SLE,polyarteritis nodosa).
The mechanism probably involves inflammatory mediators released because of ischemia,infection,or bile stasis. Sometimes an infecting organism can be identified (e.g salmonella or cytomegalovirus in immunodeficient patients). In young children, acute acalculous cholecystitis tends to follow a febrile illness without n identifiable infecting organism
Symptoms and signs
Most patients have had prior attacks of biliary colic or acute cholecystitis. The pain of cholecystitis has a quality and location similar to that of biliary colic but with longer duration (i.e > 6h) and greater severity .
Vomiting is common, as is right subcoastal tenderness. Within few hours, Murphy’s sign (deep insipiration exacerbates the pain during the pain palpation of the right upper quadrant and halts inspiration) develops with involuntary guarding of right-sided abdominal muscles. Fever usually low grade is common. In the elderly fever may not be systemic an nonspecific (e.g. anorexia,vomiting,malaise,weakness,fever).
If the disease is untreated, 10% of patients develop localized perforation, and 1% develop free perforation and peritonis.
Increasing abdominal pain, high fever, and rigors with rebound tenderness or ileus suggest empyema (pu sin the gallbladder),gangrene,or perforation.
If acute cholecystitis is accompanied by jaundice or cholestasis, partial common duct obstruction is possible, usually due to stone or inflammation.
Common duct stones passed from the gallbladder may block,narrow,or inflame the pancreatic duct,producing pancreatitis (gallstonepancreatitis).
Mirizzi’s syndrome is a rare complication in which a gallstone impacted in the cystic duct or Hartan’s pouch compresses and obstructs the common duct. Rarely, a large stone erodes the gallbladder wall, creating a cholecystoenteric fistula, the stone may pass freely or obstruct the small intestine (gallstone ileus).
Acute acalculous cholecystitis tends to cause the same symptoms as calculous cholecystitis, but the symptoms may be masked in severely ill patients who cannot communicate clearly.
The only clue may be abdominal distention or unexplained fever.
Untreated, the disease can rapidly progress to gallbladder gangrene and perforation, leading to sepsis, shock and peritonitis, with a mortality of 65%.
Choledocholithiasis and cholangitis can also develop.
Diagnosis
Acute cholecystitis is suspected in patients with suggestive symptoms and signs. Diagnosis is usually based on ultrasound, which can detect gallstones as well as focal tenderness of the gallbladder (Ultrasonographic Murphy’s Sign).
Pericholecystic fluid or thickening of the gallbladder wall indicates acute inflammation.
If results are equivocal cholescintigraphy is used, failure of the radioactivity to fill the gallbladder suggests an obstructed cystic duct. False positives can occur in critically ill or fasting patients receiving TPN, patients with severe liver diseases or those with previous sphinterotomy.
Abdominal CT may reveal cholecystitis as well as gallbladder perforation or pancreatitis.
Magnetic resonance cholangiography is accurate but more costly than ultrasound.
CBC, liver function tests, amylase, and lipase are usually obtained but are rarely diagnostic
Leukocytosis with a left shift is common .In uncomplicated acute cholecystitis there should be no marked biochemical liver function abnormalities or lipase elevations.
In acute acalculous cholecystitis,laboratory tests are not specific. Leukocytosis and abnormal liver biochemistries are common.
A cholestatic pattern may results from sepsis itself, choledocholithiasis, or cholangitis.
Ultrasonography can be performed at the bedside. Gallstone are absent..
A sonographic Murphy’s sign and pericholecystic fuid accumulation suggest gallbladder disease, whereas a distended gallbladder, biliary sludge, and a thickened gallbladder wall (from low albumin or ascites) may result simply from being critically ill.
CT is also accurate and may identify extrabiliary abnormalities.
Cholescintigraphy is more helpful, absence of filling may indicate edematous cystic duct obstruction.
However gallbladder stasis may itself prevent filling.
Giving morphine, which increases tone in the sphincter of Oddi and enhances filling, can eliminate such a false-positive result.
Treatment.
Management includes hospital admission, IV fluids, and opioids.
No oral feedings are given and nasogastric sanction is instituted if vomiting is a problem.
Parenteral antibiotics are usually initiated to treat possible infection, but evidence of benefit is lacking.
Empiric coverage is directed at gram-negative enteric organism such as Escherichia coli,Enterococus,Klebsiella and Enterobacter and can be accomplished with regimes such as piperacillin/tazobactam 4g IV q6h,ampicillin/clavulanate 4 g IV q 6h.
Cholecystectomy cures acute cholecystitis and relieves biliary pain. When the diagnosis is clear and the patient is at low surgical risk, cholecystectomy is best performed during the initial 24 to 48 hrs.
For high risk patients with severe chronic diseases (e.g cardiopulmonary) cholecystectomy should be deffered until such condition improves with medical therapy or until cholecystitis subsides.
If cholecystitis subsides cholecystectomy may be perfomed > = 6 weeks later .
Empyema,gangrene,perforation,and acalculous cholecystitis require urgent surgical management .
In patients at very high surgical risk,percutaneous cholecystostomy may be an alternative to cholecystectomy.
0 comments :
Post a Comment