The Biliary System - Inflammation and infection PDF

The Biliary System Infection and Inflammation QE II/Dalhousie School of Health Sciences DMUT 2000 – Topic 14 Inflammation of the Gallbladder Cholecystitis GB Torsion Cholecystectomy Cholecystitis  Inflam...

The Biliary System Infection and Inflammation QE II/Dalhousie School of Health Sciences DMUT 2000 – Topic 14 Inflammation of the Gallbladder Cholecystitis GB Torsion Cholecystectomy Cholecystitis  Inflammation of the gallbladder  Acute or chronic  Characterized by gallbladder wall thickening  >3mm in a fasting patient  Measurements are non-diagnostic in non-fasting patients Acute Cholecystitis  Common cause of ER visits and hospital admissions  90% of cases are caused by gallstones  No gallstones = acalculous cholecystitis  Females > males  Clinical Symptoms  Lab Tests  RUQ or epigastric pain  Leukocytosis  +ve sonographic Murphy’s   SAP sign   bilirubin (direct)  Fever  Nausea and vomiting  Jaundice Acute Cholecystitis Pathophysiology  Impacted stone causes GB neck obstruction  Trapped bile within GB becomes concentrated and chemically irritated  GB becomes distended  Venous outflow is affected, which affects arterial flow  GB may become ischemic and “super”-infected  Eventually necrotic Acute Cholecystitis Sonographic Appearance  GB wall thickening  > 3mm  Distended GB lumen  Diameter > 4cm Rumack Table 6-1  Gallstones and/or sludge  Stones are usually impacted in the GB neck  Pericholecystic fluid  Anechoic fluid around exterior of GB  Positive sonographic Murphy’s sign  Hyperemic GB wall on color/power Doppler Acute Cholecystitis Positive Sonographic Murphy’s Sign  Maximal tenderness over the GB with  transducer pressure  Best assessed from a subcostal approach, use deep inspiration  Be aware of the “medicated” patient (analgesics)  Responses will be subdued or absent  Responses may be subdued or absent in severely complicated cases as well  GB perforation or gangrene Acute Cholecystitis Sonographic Appearance Impacted stones and wall thickening Pericholecystic fluid Rumack Fig 6-39, and 6-40 Acute Cholecystitis Differential Diagnoses  Other causes of GB wall thickening  Non-fasting patient  Chronic cholecystitis  Adenomyomatosis  GB carcinoma  Edematous states  Cirrhosis, portal HTN, hepatitis, CHF, renal failure  GB wall appears more “stratified” (Fig 6-41)  GB hydrops and Courvoisier’s GB  Other causes of abdominal fluid (simulating pericholecystic fluid)  Cirrhosis, portal HTN, trauma, appendicitis etc Acute Cholecystitis Differential Diagnoses Edema (striated) from cirrhosis Non-fasting patient Chronic cholecystitis GB Hydrops (Mucocele) and Courvoisier’s Gallbladder  Both are abnormally distended gallbladders without inflammation  Thin, wall  Occur due to duct obstruction with trapped bile and mucinous secretions  May be palpable  Different causative agents and levels of obstruction  GB Hydrops (Mucocele)  Courvoisier’s GB  Level of obstruction is  Level of obstruction is cystic duct distal CBD  Cause is anything  Cause is pancreatic head obstructive neoplasm Overly distended GB measuring >12 cm in length Complications Perforated Gallbladder  Occurs in 5-10% of cases of acute cholecystitis  Due to prolonged inflammation  Sonographic Appearance  Focal defect in wall (area of perforation) may be seen  GB appears “deflated”  No longer distended  Loss of normal pear shaped  Pericholecystic fluid collection  From “escaped” bile  May see associated abscess formation or peritonitis  In pericholecystic area or extending into liver  Typical abscess features Complications Perforated Cholecystitis Focal defect in wall Perforated (deflated) GB with pericholecystic abscess Rumack Fig 6-40, Video 6-11 Complications Gangrenous Cholecystitis  Necrosis of the GB  Occurs with severe, prolonged or infected cholecystitis  Arterial blood supply is reduced or obstructed  Causes sloughing of the GB wall  Sonographic Murphy’s is usually absent  Necrosis of the nerve supply  May progress to hemorrhagic cholecystitis  Hemorrhage within GB  May present with GI bleeding Complications Gangrenous Cholecystitis  Sonographic Appearance  Bands of non-layering echogenic tissue within the GB lumen  Sloughed intraluminal membranes and blood  Irregular GB wall, +/- abscesses and/or hemorrhage  Focal sonolucent fluid collections within wall Complications Gangrenous Cholecystitis Sloughed wall layers Rumack Fig 6-40 Acalculous Cholecystitis  Acute cholecystitis with no history of gallstones  Risk factors  More commonly seen in critically ill patients (worse prognosis)  ICU patients  TPN, major trauma or surgery, sepsis  Elderly male patients with atherosclerosis (better prognosis) Acalculous Cholecystitis Sonographic Appearance  Same sonographic appearance as calculous  Except no gallstones identified  Sludge is often identified  Difficult diagnosis in critically ill patients  All signs may be seen without cholecystitis  Sludge, GB wall thickening, GB distention, pericholecystic fluid  Patient is unable to indicate sonographic Murphy’s  The more +ve findings, the more likely it is acalculous cholecystitis Acalculous Cholecystitis Sonographic Appearance Emphysematous Cholecystitis  Rare type of acute cholecystitis  May or may not have gallstones  Males > females  More common in diabetic patients  Caused by gas-forming bacterial infection  Usually after an ischemic event in the GB  Requires urgent surgical attention  Rapidly progressive and fatal in 15% of patients Emphysematous Cholecystitis Sonographic Appearance  Visualization of gas within the GB lumen and/or wall  Echogenic, linear appearance  Posterior “dirty” shadowing (ringdown)  May see movement of gas  May see air within bile ducts  Pneumobilia  May see evidence of perforation  More common in this type of cholecystitis Emphysematous Cholecystitis Sonographic Appearance Diffuse gas within wall Focal area of gas within wall, with dirty shadow with dirty shadow Rumack Fig 6-40 G,I Associated gas in ducts (pneumobilia) Chronic Cholecystitis  Usually occurs with all gallstones   same incidence and risk factors  Often asymptomatic and mild  May occur along with bouts of acute cholecystitis  May lead to thickening and fibrosis of GB wall  Chronic contraction of GB Chronic Cholecystitis Sonographic Appearance  GB wall thickening  Gallstones  GB is usually not distended  DDX  Acute cholecystitis  Absence of other findings  GB distention, +ve Murphy’s  Non-fasting GB Porcelain Gallbladder  Calcification of the GB wall  Unknown etiology  Thought to be associated with gallstone disease  May be a form of chronic cholecystitis  Females > 60 y.o.  High incidence (~7%) of gallbladder carcinoma (refuted in recent literature)   surgical removal is (still) advised Porcelain Gallbladder Sonographic Appearance  Variable degrees of calcification  Calcification occurs in the wall  Echogenic, semilunar line of varying lengths  Dense posterior acoustic shadow  May or may not see luminal contents  DDX  Gallstones (WES)  GB wall is not visible in porcelain GB  Emphysematous cholecystitis  Pneumobilia Porcelain Gallbladder Sonographic Appearance GB Torsion (Volvulus)  GB twists upon itself, obstructing arterial supply  Rare  More common in elderly females  Causes similar symptoms to acute cholecystitis  May progress to acute cholecystitis, gangrene and perforation GB Torsion (Volvulus) Sonographic Appearance  Massively distended and inflamed GB  Similar to acute cholecystitis without gallstones  GB may have an unusual “lie”  Horizontally located Cholecystitis Treatment  Acute  Laparoscopic cholecystectomy  Less complications, faster recovery  Antibiotics  Complicated acute  Surgical cholecystectomy  Chronic  Elective cholecystectomy Cholecystectomy Complications  Fluid collections (most common)  Usually in the GB fossa or peri-hepatic space  Bile leakage  Biloma  Blood  Hematoma  May become infected and progress to abscess formation  Bile duct injury  Retained stones  Choledocholithiasis  Blood vessel injury Inflammation of the Bile Ducts Cholangitis Biliary Ascaris Cholangitis  Inflammation of the biliary ducts  Subclassifications:  Acute Bacterial Cholangitis  Recurrent Pyogenic Cholangitis  AIDS Cholangitis  Primary Sclerosing Cholangitis Acute Bacterial Cholangitis  Bacterial infection of the biliary ducts  Usually by gram –ve enteric bacteria  Medical emergency  May progress to abscess formation, sepsis and death  Clinical Symptoms  Lab Tests  Charcot’s triad  Leukocytosis  Fever   SAP  RUQ pain   bilirubin  Jaundice  +ve blood cultures for bacterial agent  May be  AST/ALT Acute Bacterial Cholangitis  Usually a complication of bile duct obstruction  Choledocholithiasis (85%)  Other obstructing causes  Intrinsic neoplasms  Extrinsic neoplasms  Choledochal cysts  Strictures from trauma or surgery Acute Bacterial Cholangitis Sonographic Appearance  US used to:  Determine cause and level of obstruction  Exclude other infectious conditions  Cholecystitis  Acute hepatitis  Mirrizzi’s syndrome  Mechanical obstruction of CHD by stone in cystic duct  May cause inflammation of ducts and cholecystitis Acute Bacterial Cholangitis Sonographic Appearance  Biliary duct dilation  Seen in 75% of patients  Associated choledocholithiasis and/or sludge  Usually in distal CBD  Thickened bile duct walls  May extend into GB wall thickening  Hepatic abscesses  Late finding, typical abscess appearance  Pneumobilia  May be seen with previous intervention or  May indicate choledochoenteric fistula formation  Abnormal connection between bowel and bile ducts Acute Bacterial Cholangitis Sonographic Appearance Hepatic abscesses Choledocholithiasis, bile duct dilation and wall thickening Rumack Fig 6-14, 6-15 Pneumobilia Recurrent Pyogenic Cholangitis  AKA – Oriental cholangitis, oriental cholangiohepatitis, hepatolithiasis  More common in people of east Asian descent  Occurs due to chronic biliary obstruction, stasis and stone formation  More commonly in left lobe of liver Recurrent Pyogenic Cholangitis Complications and Treatment  Acute complications  Medical emergency  Sepsis may be fatal  Chronic recurrences  Atrophy of affected liver segments  Biliary cirrhosis  Cholangiocarcinoma  Treatment  Repeated biliary dilation and stone removal Recurrent Pyogenic Cholangitis Sonographic Appearance  Typically confined to the left lobe of the liver, rather than the entire liver  Bile duct dilation  Associated choledocholithiasis and/or sludge  Severe atrophy of the affected portion of the liver may occur  Ducts may appear as a conglomerate, heterogeneous mass See Rumack Fig 6-19 and 6-20 for images AIDS Cholangitis  AKA – HIV Cholangiopathy  Inflammatory condition of the biliary ducts  Occurs in the late stages of  Clinical symptoms HIV infection  Acute RUQ or epigastric pain  Immune compromised patients  Opportunistic infection  Lab Tests  Cryptosporidium  Markedly  SAP  Cytomegalovirus  Normal bilirubin AIDS Cholangitis Sonographic Appearance  Thickened bile duct walls  Diffuse GB wall thickening  Focal duct strictures  With subsequent proximal dilation  Dilated CBD  Due to inflammation of papilla of Vater (Papillary stenosis)  May be seen as echogenic nodule protruding into distal duct AIDS Cholangitis Sonographic Appearance Bile duct thickening Rumack Fig 6-21 GB wall thickening Sclerosing Cholangitis  Chronic inflammatory disease of the biliary ducts  Primary (PSC)  Secondary (SSC)  Unknown cause  AIDS Cholangitis  Bile duct neoplasm with clear history  Biliary tract surgery or trauma  Choledocholithiasis  Congenital abnormalities Primary Sclerosing Cholangitis  Fibrotic inflammation of ducts  Males > females  Early middle age ~40 y.o.  Usually asymptomatic  Associated conditions  IBD (Ulcerative colitis)  80%  Autoimmune disorders  Sclerosing conditions  Ex. Retroperitoneal fibrosis Primary Sclerosing Cholangitis  Duct fibrosis leads to duct strictures and cholestasis  May have intraductal stone formation (choledocholithiasis)  Eventual complications include  Biliary cirrhosis, portal HTN and hepatic failure  May require liver transplantation  Disease tends to recur  Cholangiocarcinoma  Up to 30% of cases Primary Sclerosing Cholangitis Sonographic Appearance  Irregularity of bile ducts  Variable degrees of bile duct thickening  Focal strictures  Due to wall thickening narrowing lumen  Subsequent proximal dilation  May see:  Choledocholithiasis  Findings of cirrhosis and portal HTN  A visible mass within ducts (cholangiocarcinoma) Primary Sclerosing Cholangitis Sonographic Appearance Bile duct wall thickening and strictures Rumack Fig 6-22, 6-23, Video 6-5, 6-6 Biliary Ascaris  AKA – Biliary ascariasis  Parasitic infection of the bile ducts  Parasite  Roundworm (~20-30 cm long, ~6mm in diameter)  Ascaria lumbricoides  Estimated to infect ¼ of the world’s population  More common in children  Fecal-oral transmission  Ingested into small bowel, retrograde passage into biliary ducts/GB Biliary Ascaris Complications  Causes biliary obstruction  Clinical Symptoms  Asymptomatic  Biliary colic  Cholangitis  Cholecystitis (acalculous)  Pancreatitis Biliary Ascaris Sonographic Appearance  Depends on the # of worms  Single worm  Parallel echogenic lines within the bile ducts or GB  Similar to a biliary stent  Clinical history is important  TR scans demonstrate a target appearance  Multiple worms  May appear “spaghetti-like” within distended ducts or GB  May appear as an amorphous echogenic mass  May see movement of worm(s) on real-time US Biliary Ascaris Sonographic Appearance References  Chong, W. K, & Shah, M.S. (2008). Sonography of right upper quadrant pain [Electronic version], Ultrasound Clinics, 3:1, 121-138.  Mittelstaedt, C. A. (Ed.). (1992). General ultrasound. New York, NY: Churchill Livingstone Inc.  Rubens, D.J. (2007). Ultrasound imaging of the biliary tract [Electronic version], Ultrasound Clinics, 2:3, 391-413.  Rumack, C. M. & Levine, D. (Eds.). (2018). Diagnostic ultrasound (5th ed.). Philadelphia, PA: Elsevier Inc.