33-year-old (female) with jaundice and abdominal bloating

00:02 A 33 year old female presents to the clinic for evaluation of yellowish discoloration of her skin and eyes.

00:11 She has had this problem for the past 6 months but states that it is getting worse over the past few weeks.

00:18 She also complains of repeated bouts of bloody diarrhea and abdominal pain that had been very embarassing for her.

00:25 On examination, her blood pressure is 110/60 mmHg, pulse is 90, respirations are 19 and her temperature is 36.6 Her abdomen is soft with no tenderness or rebound tenderness but the rectal examination shows blood and mucus in the rectal vault.

00:44 Her sclera appear yellow along with the face and upper body.

00:47 Laboratory results are obtained and below: AST - 170 (U/L), ALT - 250 (U/L), ALP - 120 (U/L), sodium -140 (mEq/L), and potassium - 3.8 (mEq/L) Which of the following antibodies would you expect to find in this patient? Answer choice (A) - anti-mitochondrial antibody Answer choice (B) -anti-endomysial IgA Answer choice (C) - p-ANCA Answer choice (D) - anti-CCP and answer choice (E) - anti-double stranded DNA Now take a moment to come your own answer for this question.

01:30 Okay let's tackle this question together.

01:33 Now this question is going to be a pathology question.

01:37 and given the fact that we're looking at liver enzymes, AlkPhosph, jaundice - this is going to be a GI question.

01:44 Now this is a 2-step question.

01:46 First we need to determine the diagnosis and second, we need to determine the antibodies associated with the diagnosis.

01:54 Now, the stem is very much required in this case to provide a clinical history to aid us in the diagnosis in this patient.

02:02 So let's start with step 1- let's determine the diagnosis.

02:05 Now this patient's clinical presentation of bloody diarrhea, abdominal pain, combined with jaundice is suggestive of a generalized gastrointestinal disorder.

02:16 Now the differential diagnosis here includes inflammatory bowel disease of which we are considering Crohn's and ulcerative colitis, malignancy and GI infection.

02:27 Now for this patient, malignancy seems unlikely given the absence of B symptoms such as weight loss or nights sweats and also the patient's young age of being 33 years old.

02:39 Patients with rectal and colon cancer tend to be older in age.

02:42 Now infection also seems to be unlikely given the absence of a mention of fever and the patient's long duration of symptoms of 6 months.

02:52 Now that leaves inflammatory bowel disease, Crohns and all sorts of colitis at the top of our differential.

03:00 Now if you refer to our image, we can see that each disease has distinctive features.

03:05 Now on our left we see a condition depicted as Crohn's disease and on our right we have the condition for ulcerative colitis.

03:15 Now Crohn's disease as we can see here affects the entire GI tract and commonly has skip segments.

03:25 Now with Crohns, we often have extraintestinal symptoms such as lesions of the skin and to the mouth but easy to remember that as ulcerative colitis has the word 'colitis' in it, and this tells you that it is limited to the colon.

03:42 So in comparison, Crohn's disease can have skip lesions affecting extraintestinal sites but our next condition that we see on the right, ulcerative colitis has the word 'colitis' in it really telling you it's limited to the colon.

03:55 So then, ulcerative colitis affects the large bowel or the colon and does not produce skip segments and does not have extraintestinal manifestations.

04:04 Now, given this patient's presentation, it sounds most likely the patient has ulcerative colitis and this is supported by the jaundice as well.

04:16 And this patient is likely suffering from ulcerative colitis with associated primary sclerosing cholangitis.

04:24 Now that we know the diagnosis for this patient, let us go back to the image to review some of more distinctions, to really reinforce them as it is extremely high-yield to understand the distinction between Crohn's disease and ulcerative colitis.

04:40 Now looking at the left, we see that we have ASCA IgG and IgA, antibodies associated with Crohn's disease and now we can see the whole GI tract is affected, it is discontinuous with skip segments and you have what is called transmural inflammation meaning the inflammation goes all the way down through the actual GI system not just in a mucosal level or superficially but we're gonna go all the way down to our basement membrane.

05:07 And of course, we have extraintestinal manifestations of we can have skin, eyes and also colorectal malignancy.

05:13 Now looking at the right, we have ulcerative colitis, with associated p-ANCA as the diagnostic marker and this, with the word colitis affects only the large bowel, and it is continuous in the large bowel and it is superficial - not transmural like Crohn's disease, only superficial mucosal inflammation with some extraintestinal manifestation and also a risk for colorectal malignancy.

05:36 Now let's look at step 2.

05:39 Now that we know the diagnosis in this case as most likely ulcerative colitis with associated primary sclerosing cholangitis,we need to know what antibody is associated with this condition.

05:50 Now for these patients, most of them will test positive for p-ANCA - very important to know.

05:57 Now in this case thus the answer is answer choice (C) - perinuclear anti-neutrophil cytoplasmic antibodies or most commonly known as p-ANCA.

06:07 Now let's discuss some high-yield facts for inflammatory bowel disease.

06:11 Now inflammatory bowel disease really is just a description of a group of inflammatory disorders that affect the GI tract.

06:19 The most important and notable for students taking USMLE step 1 are ulcerative colitis and Crohn's disease.

06:27 Now ulcerative colitis affects continuous segments of the GI system but it is most common in the rectum and descending colon - very high yield.

06:36 Now Crohn's disease generally affects intermittent or skip segments of the GI system and is often diagnosed based on findings in the mouth.

06:46 Now common symptoms include: bloody diarrhea, abdominal bloating and pain which you may see in the clinical vignette on the question on real exam day.

06:54 Now the treatment here can be surgical, as you can have a proctocolectomy in the case of ulcerative colitis or medical with immunosuppression although full care and full cure with medical therapy is uncommmon.