Autoimmune and Cholestatic Liver Disease: Cholestatic Liver Disease: Sclerosing Cholangitis

0:00Welcome to Board Pearls. This is episode three of three of the Autoimmune and Cholestatic Liver Disease chapter, in the Liver Disease module. This episode is primary sclerosing cholangitis, its steroid-responsive mimic, and the overlap syndromes. A man with ulcerative colitis and a fluctuating alkaline phosphatase shows who gets sclerosing cholangitis, why a normal alkaline phosphatase or an antibody can't settle the question, why magnetic resonance cholangiopancreatography, MRCP, beats endoscopic retrograde cholangiopancreatography, ERCP, for diagnosis, when a biopsy is needed, and which stain must always be done. A woman with Crohn colitis and a normal MRCP shows small-duct disease. A woman with new jaundice on surveillance shows the three cancers, why a dominant stricture is cancer until proven otherwise, which complications aren't cancer, and which treatments do harm. An older man headed for a Whipple shows immunoglobulin G4, IgG4, related cholangitis, which looks like pancreatic cancer and responds to steroids. And two patients show the overlaps, where autoimmune hepatitis blurs into the cholestatic diseases.

1:11Here's the first patient. A forty-one-year-old man has had extensive ulcerative colitis for eight years. His alkaline phosphatase has been two to three times normal on and off for two years, and normal once in between. His alanine aminotransferase, ALT, is sixty and his bilirubin is normal. He has mild itching and fatigue. His anti-mitochondrial antibody, AMA, is negative and his perinuclear antineutrophil cytoplasmic antibody, p-ANCA, is positive. His last doctor ordered an abdominal ultrasound, which was normal, and called the alkaline phosphatase a medication effect.

1:49A cholestatic pattern in a man with ulcerative colitis is primary sclerosing cholangitis until imaging says otherwise, and a medication effect isn't an explanation. Primary sclerosing cholangitis is chronic immune-mediated inflammation and fibrotic stricturing of the bile ducts inside and outside the liver. It produces multifocal strictures with normal-caliber segments between them, which gives the cholangiogram its classic beaded look. The cause probably involves aberrant gut-derived T cells, signaling between the gut and liver, bile composition, and genetic susceptibility, with the human leukocyte antigen types HLA-B8 and HLA-DR3 raising the risk.

2:34His profile is the typical one. The disease is male-predominant, about sixty-five to seventy-five percent, with a mean age at diagnosis of forty, and seventy to eighty percent of patients have inflammatory bowel disease, mostly ulcerative colitis. The reverse link is much weaker: only two to five percent of patients with ulcerative colitis, and one to two percent with Crohn disease, develop it. But a colitis patient with cholestatic liver tests needs it excluded.

3:00His symptoms place him in the smaller group at presentation. About half of new diagnoses have no symptoms and are found through cholestatic liver tests during inflammatory bowel disease care or by chance. The symptomatic group has fatigue and itching, and less often episodes of acute bacterial cholangitis with fever, jaundice, and right upper quadrant pain. The late presentation is portal hypertension and decompensated cirrhosis. Symptoms at diagnosis are a poor prognostic feature, and he has them.

3:30His labs couldn't settle it. The alkaline phosphatase, often two to three times normal, fluctuates and is normal in forty to fifty percent at any given time, so his one normal value meant nothing. The aminotransferases are usually under five times normal unless there's an autoimmune overlap or biliary obstruction, and his ALT of sixty fits. There's no diagnostic antibody. Atypical p-ANCA is positive in seventy to eighty percent, but it appears across inflammatory bowel disease, autoimmune hepatitis, and other autoimmune diseases, so in a colitis patient a positive p-ANCA says almost nothing about the bile ducts. Sclerosing cholangitis is an imaging diagnosis.

4:13The imaging has to be the right test. Ultrasound is neither sensitive nor specific and can't exclude the disease, so his normal ultrasound reassured on the wrong test. The test of choice is MRCP, and the pathognomonic finding is multifocal short-segment strictures with normal or dilated segments between them, inside the liver, outside it, or both. MRCP performs as well as ERCP for diagnosis, is non-invasive and more cost-effective, and avoids instrumenting narrowed ducts that are prone to bacterial colonization, where ERCP carries a risk of cholangitis. ERCP is reserved for therapy and sampling: a dominant stricture, ascending cholangitis, or suspected cholangiocarcinoma. His MRCP shows multifocal intrahepatic and extrahepatic strictures with beading, so he has large-duct primary sclerosing cholangitis.

5:06His diagnostic cholangiogram means he doesn't need a biopsy. A liver biopsy is required only for small-duct disease, where the cholangiogram is normal, and for a suspected autoimmune overlap, signaled by an ALT over five times normal or a high immunoglobulin G, IgG. The classic lesion is concentric periductal onion-skin fibrosis around medium-sized ducts, with ductular proliferation early and duct loss and biliary cirrhosis late. The onion-skin lesion is highly specific but uncommon in any single biopsy, because the disease is patchy, so more often the biopsy shows nonspecific portal fibrosis with mild inflammation, which doesn't argue against the diagnosis.

5:49One stain is never skipped. Every biopsy in this workup is stained for IgG4, to identify IgG4-related sclerosing cholangitis, which responds to steroids. Calling that disease primary sclerosing cholangitis withholds the one treatment that works.

6:06The second patient shows the variant that a normal MRCP hides. A thirty-four-year-old woman with Crohn colitis has a persistently high alkaline phosphatase, a negative AMA, and a normal MRCP. The normal MRCP doesn't end her workup. In small-duct disease only the small intralobular ducts are involved, and the ducts MRCP can see are spared, so diagnosis requires a biopsy plus the typical context of cholestatic liver tests, often with inflammatory bowel disease. Her biopsy shows periductal fibrosis and ductular proliferation, with a negative IgG4 stain.

6:44Small-duct disease makes up about five percent of cases and has a better prognosis than large-duct disease, with lower rates of cholangiocarcinoma, transplant, and death. But a minority progress to large-duct disease, so it isn't benign. She stays under follow-up, with the same colitis surveillance.

7:01The first man's prognosis shapes everything that follows. A large international study of more than seven thousand patients found transplant-free survival of about twenty-one years from diagnosis in the population cohort, much better than older estimates from referral centers. But about eleven to fifteen percent develop cholangiocarcinoma, about eleven percent colorectal cancer, and one to four percent gallbladder cancer, and mortality is dominated by cholangiocarcinoma and end-stage liver disease. So primary sclerosing cholangitis is a premalignant condition, and surveillance for its three cancers is the core of management from the day of diagnosis. His itching is managed with the same stepped approach as in primary biliary cholangitis, from episode two, starting with cholestyramine spaced from his other drugs.

7:49The third patient shows why that surveillance exists. A forty-six-year-old woman was diagnosed six years ago, alongside ulcerative colitis. She's had a yearly MRCP and carbohydrate antigen 19-9, CA 19-9, a colonoscopy every one to two years, and gallbladder ultrasound. Now she has new jaundice, worse itching, and eight pounds of weight loss. Her bilirubin is four point two and her CA 19-9 is two hundred ten. Her MRCP shows a new tight stricture of the common hepatic duct with dilated ducts above it.

8:26New jaundice, weight loss, a rising CA 19-9, and a new tight stricture with dilation upstream suggest cholangiocarcinoma, the dominant cancer of this disease. The lifetime risk is ten to fifteen percent, and up to twenty in some series, roughly four hundred times the general population. The annual incidence is about one percent and highest in the first one to two years after diagnosis, so the first years are the highest-risk period. Risk is enriched in older patients, men, long-standing ulcerative colitis, and dominant strictures, and the premalignant lesion is biliary dysplasia in flat or papillary epithelium. Surveillance is a yearly MRCP plus a serum CA 19-9 in adults with large-duct disease. Her years of colitis and her new dominant stricture both raise her risk.

9:13Her CA 19-9 is suggestive but can mislead. It rises with bacterial cholangitis and nonspecifically in many cholestatic conditions, and it's uninformative in Lewis-negative patients, who can't make the antigen, so their yearly MRCP carries the surveillance alone. A markedly raised CA 19-9, over about one hundred thirty to one hundred fifty units per milliliter, raises suspicion without establishing the diagnosis. Hers is two hundred ten without fever, so cholangitis doesn't explain it. Three MRCP findings suggest cholangiocarcinoma: a new dominant stricture, a mass-forming lesion, or progressive dilation of the ducts above a stricture. She has the first and the third.

9:58Her new stricture is a dominant stricture, a single stenosis out of proportion to the rest of the cholangiogram, classically a common duct under one and a half millimeters or a hepatic duct under one millimeter. Dominant strictures develop in about thirty to fifty percent of patients over the course of the disease and present with new jaundice, itching, weight loss, or recurrent cholangitis. Any dominant stricture is assumed to harbor cholangiocarcinoma until proven otherwise, especially with weight loss or a rapid change in the labs, so it's sampled before it's dilated.

10:30The sampling follows a fixed order. ERCP brushings are sent for cytology and for fluorescence in situ hybridization, FISH, which detects chromosomal polysomy and is more sensitive than cytology alone, though it needs specialized expertise. If cytology and FISH aren't diagnostic but suspicion remains, cholangioscopy with directed biopsy follows. A stricture proven benign is dilated endoscopically, with or without a short-term stent, under antibiotic prophylaxis, and stays under close surveillance.

11:04Her brushings show atypia, her FISH shows polysomy, and cholangioscopic biopsies show adenocarcinoma: a hilar cholangiocarcinoma under three centimeters with no spread outside the liver. Patients who meet the Mayo criteria may be eligible for neoadjuvant chemoradiation followed by liver transplant. The criteria are a hilar cholangiocarcinoma, a mass under three centimeters, no extrahepatic spread, and no transperitoneal biopsy of the mass, which is why her tissue came from inside the duct. Selected protocols report about sixty-five percent survival at five years, and after transplant for cholangiocarcinoma, survival at one year is about ninety percent, with recurrence in about twenty percent by five years. She meets all four criteria and is referred. Chapter twenty-four covers the protocol.

11:55Her surveillance also covered the other two cancers. Primary sclerosing cholangitis with inflammatory bowel disease raises colorectal cancer risk about five to ten times over inflammatory bowel disease alone, even when the colitis is mild or in remission. The colitis is a pancolitis with right-sided predominance, rectal sparing, and backwash ileitis, and its cancer often arises in flat dysplasia rather than in polyps. Colonoscopy with random and targeted biopsies is done at the diagnosis of sclerosing cholangitis, whether or not inflammatory bowel disease is known, and then every one to two years. About five to ten percent of patients have silent inflammatory bowel disease found on that first colonoscopy, and they join the same interval. Chapter fourteen covers the techniques.

12:42Gallbladder cancer is uncommon, one to four percent over a lifetime, but the risk per polyp is much higher than in the general population. So the twenty twenty-two American Association for the Study of Liver Diseases, AASLD, guidance and the American College of Gastroenterology, ACG, guideline recommend cholecystectomy for polyps over eight millimeters, rather than the general-population cutoff of ten. Polyps of eight millimeters or smaller are followed with ultrasound every six months, and a yearly right upper quadrant ultrasound, often paired with the yearly magnetic resonance imaging, MRI, is standard. A forty-nine-year-old man with a nine-millimeter polyp, told by a friend that polyps under a centimeter are watched, is referred for cholecystectomy.

13:29Liver cancer is a smaller fourth risk. Hepatocellular carcinoma is uncommon in this disease, two percent or lower even with cirrhosis, so ultrasound and alpha-fetoprotein, AFP, every six months is for patients with cirrhosis only, as in any cirrhosis.

13:46Not every complication is cancer, and few treatments help. Recurrent bacterial cholangitis is treated with the appropriate antibiotic, and with short-course stenting if obstruction drives it. Portal hypertension with variceal bleeding can come from portal fibrosis before cirrhosis, so the absence of cirrhosis doesn't exclude varices. Fat-soluble vitamin deficiencies develop and are replaced.

14:09No medical treatment is proven. High-dose ursodeoxycholic acid, UDCA, over twenty-eight milligrams per kilogram a day, increased mortality and colorectal cancer risk in a randomized trial and is contraindicated. Standard-dose UDCA is contentious and isn't formally recommended by AASLD, though some clinicians prescribe it. Oral vancomycin, one hundred twenty-five milligrams three times a day, lowers the alkaline phosphatase in small studies but has no survival data, and farnesoid X receptor, FXR, agonists such as cilofexor are in trials. Transplant is the definitive therapy, indicated for decompensated cirrhosis, refractory itching, recurrent cholangitis that affects quality of life, and Mayo-criteria hilar cholangiocarcinoma.

14:59The IgG4 stain in the first man's workup exists because of the next patient. A sixty-eight-year-old man has painless jaundice and twelve pounds of weight loss. His bilirubin is seven and his alkaline phosphatase five hundred. Computed tomography, CT, shows a diffusely enlarged, sausage-shaped pancreas with a thin low-density rim and a stricture of the distal common bile duct. His surgeon is discussing a Whipple.

15:23Painless jaundice, a distal bile duct stricture, and a sausage-shaped pancreas in an older man suggest IgG4-related sclerosing cholangitis, not cancer. It's the hepatobiliary form of IgG4-related disease, a systemic fibroinflammatory disorder driven by oligoclonal expansions of IgG4-secreting plasma cells, with characteristic histology and a striking response to corticosteroids. The bile duct is its most common site outside the pancreas. It typically affects men over sixty and presents with painless obstructive jaundice, often with weight loss, which is why it mimics pancreatic or biliary cancer, and it most often involves the distal common bile duct, with or without intrahepatic strictures. Sixty to eighty percent have type one autoimmune pancreatitis at the same time. Every feature that suggests cancer to his surgeon also fits this disease.

16:18His imaging also separates it from primary sclerosing cholangitis. Sclerosing cholangitis strictures are short and multifocal, with normal segments between them. IgG4-related strictures are tight and segmental, made by inflammatory masses in the duct wall, with long, sausage-like dilations between them, and distal duct strictures dominate, often with pruning of the peripheral intrahepatic ducts. Type one autoimmune pancreatitis gives a diffuse, sausage-shaped enlargement with a low-density, capsule-like rim, a recognition pattern in itself, and that's his CT.

16:51The diagnosis is made by the HISORt criteria, developed for autoimmune pancreatitis and applied to the bile duct disease: histology, imaging, serology, other organ involvement, and response to therapy. The histologic triad is a dense lymphoplasmacytic infiltrate, storiform fibrosis, a mat-like swirling pattern, and obliterative phlebitis, with more than ten IgG4-positive plasma cells per high-power field, often more than fifty, and an IgG4-to-IgG ratio above forty percent. Serum IgG4 is raised above one point four grams per liter, one hundred thirty-five to one hundred forty milligrams per deciliter, in sixty to seventy percent. The pancreas has its own set, the International Consensus Diagnostic Criteria for autoimmune pancreatitis.

17:41Serum IgG4 fails in both directions. A normal level doesn't exclude the disease, and modest elevations appear in primary sclerosing cholangitis, cholangiocarcinoma, and other inflammatory states. That's why the criteria combine five domains, and why tissue is stained for IgG4. Even with a normal IgG4, his pancreas would call for tissue before any operation.

18:04So his next step isn't the Whipple. In an older man with painless jaundice, a distal bile duct stricture, pancreatic enlargement, and a raised IgG4, the next step is a biopsy with IgG4 staining and a steroid trial. His serum IgG4 is three hundred twenty, and his biopsy shows a dense lymphoplasmacytic infiltrate with storiform fibrosis and abundant IgG4-positive plasma cells.

18:30Treatment is prednisone forty milligrams a day for four weeks, then a taper of five milligrams a week, and a response usually appears within two to four weeks: the strictures resolve, the alkaline phosphatase normalizes, and the pancreas shrinks. That response is the R in HISORt. A cancer wouldn't respond, so a stricture that doesn't change on steroids reopens the question of cancer. His jaundice clears within three weeks, and repeat imaging shows the stricture open and the pancreas smaller.

18:59His disease is likely to come back. Relapse occurs in up to half of patients, and azathioprine, mycophenolate mofetil, or rituximab can be added for steroid-sparing maintenance or for relapse. A year after his taper, his alkaline phosphatase rises and his stricture returns, so he restarts steroids and adds rituximab for maintenance. Chapter twenty-six covers autoimmune pancreatitis.

19:25The last two patients show the overlaps, where autoimmune hepatitis joins a cholestatic disease. A fifty-six-year-old woman with primary biliary cholangitis on UDCA has an ALT that has climbed to two hundred sixty, more than five times normal, and an IgG over twice the upper limit. A climbing ALT on UDCA suggests autoimmune hepatitis overlapping her primary biliary cholangitis. About five percent of patients with primary biliary cholangitis develop a hepatocellular component, which makes it the most common overlap.

19:57The Paris criteria require at least two of three features for each disease. For autoimmune hepatitis they are an ALT of five times normal or more; an IgG of twice normal or more, or a positive smooth muscle antibody; and moderate to severe periportal interface hepatitis on biopsy. For primary biliary cholangitis they are an alkaline phosphatase of twice normal or more, or a gamma-glutamyl transpeptidase, GGT, of five times normal or more; an AMA of one to forty or higher; and a florid duct lesion on biopsy.

20:32She meets both sets. Her ALT and IgG give two autoimmune features from the labs alone, her AMA and alkaline phosphatase give two cholestatic features, and her biopsy shows moderate interface hepatitis alongside the duct lesion. She's treated for both diseases: UDCA, thirteen to fifteen milligrams per kilogram a day, for the cholestatic component, plus prednisone with or without azathioprine for the hepatocellular component, with both sets of tests monitored. UDCA alone won't control interface hepatitis, and steroids alone won't treat the duct disease, so either component progresses if it's left untreated.

21:08Autoimmune hepatitis can also overlap with primary sclerosing cholangitis. A sixteen-year-old boy with ulcerative colitis has a high ALT and IgG, autoantibodies, and interface hepatitis on biopsy, and his MRCP shows the strictures of sclerosing cholangitis. This overlap is rare in adults and more common in children and adolescents, where it's sometimes called autoimmune sclerosing cholangitis, and the diagnosis requires the autoimmune features together with the sclerosing cholangitis cholangiogram. Treatment is UDCA plus prednisone and azathioprine. The autoimmune side often responds, with the ALT normalizing, while the sclerosing side stays stable or slowly progresses, since it has no proven therapy. Outcomes fall between pure autoimmune hepatitis and pure sclerosing cholangitis, and the cancer surveillance still applies.

22:02Here are the traps the boards set in these patients. A normal alkaline phosphatase doesn't rule out sclerosing cholangitis. p-ANCA doesn't diagnose it, and ultrasound can't exclude it. ERCP isn't the diagnostic test. A patient with a diagnostic MRCP doesn't need a biopsy, and a nonspecific biopsy doesn't exclude the disease. The IgG4 stain is never skipped. A normal MRCP doesn't end the workup when small-duct disease is possible, and small-duct disease isn't benign. And cancer surveillance starts at diagnosis, not when symptoms appear.

22:38The surveillance traps follow. The yearly MRCP and CA 19-9 aren't optional. A normal CA 19-9 doesn't exclude cancer, especially in a Lewis-negative patient, and a high one during cholangitis doesn't establish it. A dominant stricture isn't dilated without brushings and FISH. A hilar mass in a possible transplant candidate isn't biopsied through the skin. Gallbladder polyps come out at more than eight millimeters, not ten. Colonoscopy is done at diagnosis even without known inflammatory bowel disease, and it isn't spaced out because the colitis is mild. Liver cancer screening is only for cirrhosis. High-dose UDCA is harmful. And selected hilar cholangiocarcinoma can be transplanted.

23:20The traps around the mimic and the overlaps close the list. An older man with painless jaundice and a sausage-shaped pancreas doesn't go to a Whipple without an IgG4 workup. A normal serum IgG4 doesn't exclude IgG4-related disease, and a mildly raised level doesn't establish it. Steroids aren't stopped without a plan for relapse. A climbing ALT on UDCA can mean an autoimmune overlap. And an overlap isn't treated with UDCA alone or steroids alone.

23:53So, start to finish. Primary sclerosing cholangitis is immune stricturing of the larger bile ducts, mostly in men around forty with ulcerative colitis. Diagnose it with MRCP, keep ERCP for therapy and sampling, and biopsy only for suspected small-duct disease or autoimmune overlap, always with an IgG4 stain. A normal alkaline phosphatase doesn't exclude it, ultrasound can't, and there's no diagnostic antibody. Small-duct disease has a normal cholangiogram and a better prognosis but can progress.

24:28Treat it as premalignant from the day of diagnosis. Do a yearly MRCP and CA 19-9, remembering that CA 19-9 fails in cholangitis and in Lewis-negative patients. Treat a dominant stricture as cancer until brushings, FISH, and often cholangioscopy say otherwise. Remove the gallbladder for polyps over eight millimeters, do colonoscopy at diagnosis and every one to two years with inflammatory bowel disease, and screen for liver cancer only with cirrhosis. No drug changes the course, and high-dose UDCA is harmful. Transplant for decompensation, recurrent cholangitis, refractory itching, or selected hilar cholangiocarcinoma.

25:11An older man with painless jaundice, a distal bile duct stricture, and a sausage-shaped pancreas has IgG4-related cholangitis until proven otherwise. Check IgG4, stain tissue, and give a steroid trial, prednisone forty milligrams for four weeks and then tapering by five a week, before any Whipple. Expect relapse in up to half, and maintain with azathioprine, mycophenolate, or rituximab.

25:37Primary biliary cholangitis with an ALT of five times normal or an IgG of twice normal may be the autoimmune overlap by the Paris criteria. Confirm it by biopsy and treat with UDCA plus immunosuppression, the same combination used for the overlap of autoimmune hepatitis and sclerosing cholangitis in the young.

25:58That completes the Autoimmune and Cholestatic Liver Disease chapter. The next chapter is steatotic liver disease.

26:05For the full chapter, the practice vignettes, and the topic-tagged question bank, head to board pearls dot com. You'll find the rest of the series on Apple Podcasts, Spotify, or wherever you listen to podcasts. That brings us to the end of episode three of three of chapter twenty, and I'll see you in the next one.