Gallstone disease is a relatively common disorder occurring in both sexes with prevalence in order of 6%to 9% in the adult population. The high prevalence of GSD(Gallbladder stone disease) is seen in northern and eastern regions of India.
Gallbladder is a small pear-shaped organ located on the undersurface of the liver.It is a reservoir for bile secreted by the liver which is delivered to duodenum in response to neurohormonal signals after meals for digestion of fatty food.
The bile contains cholesterol,bile salts and phospholipids in certain proportion to remain in soluble liquid form.The supersaturation of bile with cholesterol allows it to form cholesterol crystals and with delayed emptying of GB function and bile stasis it eventually leads to stone formation.Genetic succeptibility,obesity,diabetes mellitus,dyslipidemia,rapid weight loss,cirrhosis,IBD,female sex, oral contraceptive and hemolytic aneamia are risk factors for Gall stone formation.
There are mainly three types of stones found in gallbladder disease. The majority of patients have mixed stone(80%),cholesterol and pigment stones are seen in 13% and 5 to7% patients respectively.The gallstones associated with GSD are found in various forms like small multiple stones,medium sized faceted stones,solitary stone,gravel and sludge in gallbladder. Gallbladder stone disease presents in three ways
1. Asymptomatic or silent
2.Symptomatic as in Chronic calculous cholecystitis and
3.Complications like Acute calculous cholecystitis,Empyema GB,Obstructive jaundice with stone obstructing CBD, Cholangitis and Acute biliary pancreatitis.
1.Silent or Asymptomatic : This kind is generally picked up as incidental finding on abdominal sonography done for other purposes or in routine health check up.These can be observed without any surgical intervention if there are no other significant risk factors like diabetes mellitus.
2.Symptomatic GB (Chronic calculous cholecystitis) : The presentation here can vary from dyspeptic symptoms to dull ache in the upper abdomen centrally or below the right rib cage typically after heavy fatty meals.Gallstones are generally detected on sonography upon advise of treating physician.Symptomatic GB are usually offered laparoscopic cholecystectomy treatment (removal of gallbladder with stone by laparoscopic surgery) after evaluation by physician to get rid of symptoms and to avoid future complications.
3.Presentation with complications :
a.) Acute calculous cholecystitis (ACC) :
The patient presents with intense pain below the right rib cage referred to back with vomiting,mild fever at times with difficulty in breathing.The patient needs immediate hospitalisation for administration of antibiotics & analgesics and for evaluation with laboratory investigation and radiology investigation like sonography or CT scan to establish severity of disease.
This kind of presentation generally occurs when gallstone gets impacted in the neck of GB or cystic duct leading to abnormal distension of GB with inflammation and thickening of gallbladder wall and exudation of pericholecystic fluid around GB.The obstructed GB gets distended with mucus forming mucocele in initial stages but with proliferation of germs may turn it into empyema of gallbladder(infected bile or pus in gallbladder).The compromise of blood supply in severely inflamed gallbladder wall may lead to gangrene or perforation of gallbladder and peritonitis,life threatening condition if not treated timely.
ACC will need early surgical intervention, ideally within 72 hrs,either with laparoscopic or open cholecystectomy after preoperative evaluation and stabilising the patient hemodynamically. During the course of surgery, depending upon severity of inflammation leading to obscure anatomy precluding safe procedure,surgeon may take a call to convert laparoscopic to open surgery or may go ahead with subtotal cholecystectomy to avoid injuries to vital structures in that area like major vessels and common bile duct.
At times one has to resort to cholecystostomy procedure of tube drainage of infected bile where definitive procedure of delayed cholecystectomy is carried out at later date after subsidence of inflammation.
In certain critically ill patients of ACC, with cardiopulmonary comorbidities,making them unfit to undergo surgery,percutaneous transhepatic cholecystostomy that is insertion of pigtail catheter under ultrasound or CT guidance by Interventional Radiologist is carried out to control the source of infection.
b.)Obstructive jaundice due to stone in CBD and cholangitis :
In few patients who have ignored there vague abdominal symptoms in the past, presents with this complication where gallstones from gallbladder travels down the CBD (common bile duct)and gets obstructed in its course through CBD leading to severe spasmodic pain and signs of obstructive jaundice. Typically a patient presents with a triad of pain, fever and jaundice. The laboratory investigation on blood reveals leukocytosis (raised white cell count)and altered liver function with raised levels of bilirubin and liver enzymes.
The patient undergoes evaluation with suitable radiological investigation like sonography, CECT and MRCP.The sophisticated investigation like EUS ( endo ultrasound)provides better information regarding nature and level of exact obstruction due to its proximity with pathology.
The therapeutic ERCP with extraction of stone with various means followed by biliary stent insertion to facilitate bile drainage plays a major role in the management of CBD stones. This is followed with laparoscopic cholecystectomy for gallbladder stone disease to get rid of the source for the present pathology during the same hospital admission.
c.) Acute biliary pancreatitis (Gallstone pancreatitis) :
Occasionally the patient can present with features of acute pancreatitis with gallstone either obstructing or migrating after transient obstruction at ampulla(common channel joining CBD and pancreatic duct,opening in duodenum).Though pathogenesis of ABP is not well understood, it is most likely due to reflux of infected bile into pancreatic duct inciting pancreatic inflammation.Acute biliary pancreatitis is potentially life threatening condition and may require ICU management to prevent multiorgan dysfunction.
The simultaneous evaluation to ascertain the prognosis is carried out with laboratory investigation of pancreatic enzyme levels and inflammatory markers.The radiological investigations like CT contrast study and MRI will stage the severity and aid in the management.
The early endoscopic biliary clearance with the sphincterotomy to relieve the obstruction at the ampulla with therapeutic ERCP is mostly beneficial.
The timing of cholecystectomy for gallstone disease following ERCP for acute biliary pancreatitis can vary markedly depending on the severity of pancreatitis.