small bowel + Flashcards
A 39-year-old woman presents with 6 years of epigastric abdominal pain and nausea. She was treated for an “ulcer” in the past, and then was diagnosed with functional dyspepsia on a clinical basis, but never had a GI-specific evaluation. She has rare non-bloody emesis, but no heartburn, dysphagia, diarrhea, hematochezia, or melena, although stool is sometimes loose. Over the last 6 months, she has lost approximately 5 lb because her appetite has been poor. She works in a pet store, has not travelled outside the U.S., and is on a municipal water supply. She has a cousin with Crohn’s disease, and her mother has rheumatoid arthritis.
On physical exam, her vital signs are normal. There is mild conjunctival pallor, and mild epigastric tenderness on palpation, but no other pertinent findings. Complete blood count shows a hemoglobin of 10 g/dL with a mean corpuscular volume of 77 fL and a peripheral eosinophil count of 1.1 cells x 109/L. Upper endoscopy is performed and a view of the stomach is shown in the figure. Biopsies of the esophagus and duodenum are normal, but the stomach has sheets of infiltrating eosinophils with 100 eosinophils per high-power field diffusely. Which of the following tests should be performed before eosinophilic gastritis can be diagnosed?
A. Stool exam for ova and parasites
B. Hemoglobin electrophoresis
C. Temporal artery biopsy
D. Celiac serology panel
This endoscopy shows prominent erythema and nodularity in the gastric body and antrum, and is suggestive of eosinophilic gastritis (EG), though the findings are nonspecific. The biopsies are also highly suggestive of EG, as is the peripheral eosinophilia. However, prior to a diagnosis of EG, causes of secondary eosinophilia must be considered and excluded as necessary. Given this patient’s history, there is a concern for an occult parasitic infection (though normal duodenal biopsies make this less likely) so stool for oval and parasites, and potential serology for other parasitic infections should be assessed. The endoscopic findings likely explain the patient’s mild anemia, and laboratory test results are not consistent with a hemoglobinopathy so hemoglobin electrophoresis is not needed. While rheumatologic and connective tissue disorders can be rare causes of eosinophilia, there is nothing to suggest these diagnoses on history and physical, and since a diagnosis of vasculitis or temporal arteritis is not being entertained, temporal artery biopsy is not indicated. While celiac disease can present with anemia and weight loss, the normal biopsies exclude this condition so further serology is not needed.
A 34-year-old man is referred for diarrhea that has been present for 9 months. He has also noticed the onset of a pruritic skin rash on his hands and arms. His medical history is unremarkable, and he is on no medications. His IgA tissue transglutaminase antibody is minimally positive, so he is sent for an esophagogastroduodenoscopy to evaluate for celiac disease. When performing his procedure, you note that his duodenum has the appearance shown in the figure. Which of the following is the best biopsy strategy?
A. 4 biopsies from the post-bulbar duodenum
B. 2 biopsies from the duodenal bulb and 4 from the post-bulbar duodenum
C. 1 biopsy each from the duodenal bulb and the post-bulbar duodenum
D. 8 biopsies from the post-bulbar duodenum
E. 4 biopsies from the duodenal bulb
This patient has a duodenum that reveals flattened folds, which is the most common endoscopic abnormality that may be seen in patients with celiac disease. However, most patients with celiac disease have a completely normal duodenum on visual inspection, so an endoscopist should biopsy the small bowel based on clinical features rather than relying on endoscopic findings. In patients undergoing an evaluation for celiac disease, duodenal bulb biopsies increase the diagnostic yield by 9-13%. In those with established celiac disease, these additional biopsies of the duodenal bulb can uncover villous atrophy that may not be seen on post-bulbar biopsies in 14% of this patient group. The highest sensitivity (reported as 100%) has been achieved when 4 post-bulbar biopsies were combined with bulb biopsies from both the 9- and 12-o’clock positions, given these are the most dependent locations within the duodenal bulb that have the most contact with ingested food when eating in the upright position, altered when the patient is positioned on the left side for upper endoscopy.
A 24-year-old woman with a history of newly diagnosed cystic fibrosis and pancreatic insufficiency was admitted for abdominal pain. Three days prior to admission, the patient woke up with periumbilical abdominal pain, nausea, and vomiting. She is afebrile. Physical exam is notable for positive bowel sounds and abdominal distention with diffuse mild tenderness, but without rebound or guarding. She had been having regular bowel movements prior to this admission but had noted some epigastric pain, bloating, and gas. She reports a prior admission with constipation but attributes that episode to being related to narcotic use in a postsurgery period. She recently tried polyethylene glycol without success. Abdominal plain film is shown in the figure. Which of the following is the most likely diagnosis?
A. Intussusception
B. Distal intestinal obstruction syndrome (DIOS)
C. Appendicitis
D. Volvulus
- GI findings, including constipation, in the cystic fibrosis (CF) population are common. Distal intestinal obstruction syndrome (DIOS) is characterized by partial or complete obstruction due to fecal material in the ileocecal/right colon region. Differentiating DIOS from constipation can be difficult but DIOS is more often associated with acute obstruction involving the ileocecal area whereas constipation is more gradual with stool burden throughout the colon.
- Risk factors for DIOS include genotype, pancreatic insufficiency and prior episodes of DIOS.
- The differential diagnosis for DIOS includes appendicitis, volvulus, and intussusception.
- However, the clinical story and imaging here support a diagnosis of DIOS with stool in the right colon and terminal ileum, no fever, and no classic imaging findings for volvulus or intussusception.
- Patients with partial DIOS usually respond to aggressive oral rehydration and laxatives. More severe cases may require contrast enemas. Prevention of recurrence with oral laxatives is important.
A 65-year-old man with metastatic melanoma is referred by his oncologist for a colonoscopy for recent bloody diarrhea that has been present for 3 months. When performing the colonoscopy, you find the following endoscopic findings throughout the entire colon [FIGURE]. The biopsies ultimately come back revealing chronic active colitis. Which of the following oncologic therapies could be to blame?
A. Sorafenib
B. Imatinib
C. Rituximab
D. Ipilimumab
Checkpoint inhibitors are immune-stimulatory antibodies that are used in the management of metastatic melanoma and other cancers. They work by blocking inhibitory signals to cytotoxic T-lymphocytes to enhance immune function. Checkpoint inhibitors may have different targets, such as cytotoxic T-lymphocyte associated antigen-4 (ipilimumab), or programmed cell death-1 receptor (embrolizumab, atezolizumab, nivolumab). Checkpoint inhibitor-induced colitis shares phenotypic, serologic and histologic features of both Crohn’s and ulcerative colitis. Symptoms range from mild diarrhea and pain to severe colitis to perforation and death. Ipilimumab is associated with diarrhea in 31-36% of patients, and up to 5% experience grade 3-4 colitis. Discussion with the treating oncologist is essential, to review the ongoing need for the checkpoint inhibitor, and to see if the therapy can be interrupted to ensure management of the colitis, which is typically treated with steroids in the acute setting, but some patients may need ongoing immunosuppression.
A 63-year-old woman with chronic hepatitis B has a sister who was recently diagnosed with hepatitis B associated hepatocellular carcinoma. Your patient asks you about a recently published article on an investigational new drug to prevent development of hepatocellular carcinoma in hepatitis B patients with first-degree relatives with hepatitis B associated hepatocellular carcinoma. The patient brings a copy of the article for your review. In the article, 1,000 patients were treated with the investigational new drug, while 3,000 patients were treated with placebo. In the 5-year follow-up period, 30 of those who received the investigational therapy developed hepatocellular carcinoma, while 150 of those who received placebo developed hepatocellular carcinoma. What is the number of patients needed to be treated with the investigational new drug to prevent development of 1 case of hepatocellular carcinoma?
A. 7 patients
B. 25 patients
C. 50 patients
D. 100 patients
Calculation of the number needed to treat or number needed to harm is a common biostatistics question. To determine the number needed to treat, this is calculated by computing (1 / Absolute Risk Reduction). The absolute risk reduction is calculated by subtracting risk of development of outcome in the exposed group from risk of development of outcome in the unexposed group. Using a 2 x 2 table, this can be visualized using the formula a/(a+b) – c/(c+d). In this scenario, the number needed to treat is calculated as follows:
Risk in Investigational Treatment Group: 30/1000 = 0.03
Risk in Placebo Group: 150/3000 = 0.05
Absolute Risk Reduction: Absolute Value of Risk in Investigational Treatment Group - Risk in Placebo Group = | 0.03 – 0.05 | = | – 0.02 | = 0.02.
Number Needed to Treat: 1 / Absolute Risk Reduction = 1 / 0.02 = 50.
Which of the following conditions requires dosage adjustments of budesonide?
A. Cirrhosis
B. Kidney impairment
C. ALT >100 U/L
D. Hepatitis B core antibody positive
Budesonide requires dose reduction in Childs B cirrhosis and should not be prescribed in Child’s C cirrhotics due to impaired first pass metabolism and increased systemic exposure. There is no absolute level of ALT that budesonide is contraindicated. The presence of antibody to hepatitis B core antigen is not a contraindication to budesonide although periodic surveillance of liver tests or hepatitis B DNA can be considered if prolonged exposure occurs.
A 38-year-old woman presents with abdominal pain that has been present for 3 years. The pain is always located at a 2-cm spot in the right lower quadrant, 5 cm to the right of the midline and 7 cm superior to the right inguinal ligament. The pain is sharp and aggravated by lying on the right side or coughing. It is not present when she wakes in the morning, but begins as soon as she gets out of bed. She has given up going to the gym “because sit-ups aggravate the pain.” The pain is not associated with meals or bloating. It sometimes is aggravated by straining to have a bowel movement. She has 4 bowel movements each week, mostly without straining. She has not lost any weight, never has blood in her stools, and has had regular menses.
Physical examination shows a middle-aged woman in no distress. Her weight is 150 lb, height 64 in, pulse 72, BP 125/70. Abdomen is soft, not distended. There is an area of tenderness in the right lower quadrant at the edge of the rectus sheath; pressing with a single finger duplicates the pain. Bowel sounds are normal. There is no organomegaly or mass. Rectal examination is unremarkable. The diagnosis is most likely to be established by which of the following tests or therapeutic trials?
A. Colonoscopy
B. CT scan of the abdomen
C. Electromyography (EMG) of the abdominal wall
D. 30-day trial of amitriptyline 10 mg nightly
E. Trigger-point injection with lidocaine
This patient is suffering with a common cause for chronic abdominal pain, Anterior Cutaneous Nerve Entrapment Syndrome (ACNES), and gives a typical history for this condition. Key historical features are localization to a single spot on the abdomen, sharp quality of the pain, and aggravation by lying on the same side as the pain or daily activities, along with lack of association with meals, bloating, or abnormal stool consistency. The physical finding of point tenderness at the edge of the rectus sheath also is a typical location for this condition. An 18-item questionnaire has been developed and has 94% sensitivity and 92% specificity for diagnosis of ACNES. Of the tests or therapeutic trials listed as answers, trigger-point injection with local anesthetic confirms the diagnosis, if it results in immediate resolution of pain and tenderness. Gastroenterologists should be able to inject trigger points in the abdominal wall with local anesthetic for diagnostic purposes in their offices. ACNES is less responsive to tricyclic antidepressants. Colonoscopy, CT, and EMG would be expected to be normal in this case.
https://pubmed.ncbi.nlm.nih.gov/24204070/
Which of the following patients is the most likely to develop tardive dyskinesia from metoclopramide?
A. An 80-year-old woman on 10 mg 3 times daily for 8 weeks for nausea
B. A 32-year-old man on 10 mg 4 times daily for 4 weeks for migraines
C. An 18-year-old woman on 15 mg 4 times daily for 14 weeks for gastroparesis due to diabetes
D. A 74-year-old man on 15 mg 3 times daily for 10 weeks for refractory reflux
- Metoclopramide is a commonly used medication, and has been reported as one of the top 200 medications prescribed over the last 5 years, prescribed by physicians for nausea, refractory reflux, migraines and most commonly, for gastroparesis.
- The risk of extrapyramidal effects are highest in patients who are: 1) under 20 years of age; 2) on high-dose therapy; and 3) on prolonged therapy.
- Tardive dyskinesia more likely to occur with use longer than 3 months, and the FDA recommends the drug be used short-term, ideally less than 12 weeks.
- In 2009, the FDA issued a black box warning for those with chronic or high-dose use given the concern over tardive dyskinesia. Before the black box warning, 69.8% of patients received metoclopramide for gastroparesis, compared with 23.7% after the warning.
- The person who is at highest risk would be the 18-year-old woman on 15 mg 4 times daily for 14 weeks given her gastroparesis due to diabetes, as her age, high-dosed therapy, and duration of therapy greater that 12 weeks all increases her risk.
A 35-year-old man presents with bloating that starts 45 minutes after eating meals. He is able to consume his usual amount of food within 20 minutes without discomfort, nausea, vomiting, or excessive belching. The sensation of bloating begins 45 minutes after most meals and peaks 20 minutes later. His abdomen feels “full” at that time and his pants feel “tight,” but symptoms subside over the next 30 minutes. He has no excessive flatus, has normal consistency bowel movements daily, and has not lost any weight. Physical examination done while he was symptomatic showed no abdominal distention and no tympany. The symptoms occur multiple days per week and have been present several years. Dairy avoidance and dietary review have not revealed a source of his bloating. Other work-up has been negative. What is the diagnosis?
A. Aerophagia
B. Gastroparesis
C. Functional dyspepsia
D. Functional bloating
E. Constipation
- Bloating is one of the more difficult symptoms for physicians to decipher as it means different things to different patients. Bloating is a symptom associated with accumulation of gas and development of abdominal distention, but patients often apply the term to the feeling of gaseous distention without necessarily becoming visibly distended. Even in those patients with a complaint of distention, many do not have objective evidence of excess gastrointestinal gas.
- Many different problems can present with bloating. Patients with bloating can be sorted into 3 categories: gastric bloaters, small bowel bloaters, and constipated bloaters. These are sorted out by the time that it takes to develop symptoms after eating and whether or not constipation is present.
- Gastric bloaters develop symptoms in <30 minutes and may have gastric outlet obstruction, gastroparesis, and disordered gastric accommodation or functional dyspepsia as underlying causes.
- Small bowel bloaters develop symptoms in >30 minutes and may have dietary carbohydrate intolerance, small bowel obstruction, celiac disease, small intestinal bacterial overgrowth, or functional bloating as underlying causes.
- Constipation also may be accompanied by bloating which may resolve with effective management of constipation.
- Patients with aerophagia also may complain of bloating, but often have belching or tympany on physical examination.
A 38-year-old woman with history of Roux-en-Y gastric bypass in 2013 presents to your office regarding ulcer management. Two weeks prior to her visit she was admitted to a local hospital for this pain and an upper endoscopy was performed that showed a clean-based marginal ulceration. She was started on an H2-blocker and referred to your office for consultation. She also reports that she had an ulcer roughly 1 year after the gastric bypass surgery and that she completed a course of treatment for H. pylori at that time. Which of the following is the best test to assess H. pylori status in this patient?
A. H. pylori serology
B. H. pylori breath test
C. H. pylori fecal antigen
D. Repeat upper endoscopy with biopsy of the gastric pouch
E. Evaluation of H. pylori is not necessary in this patient
- In Roux-en-Y anatomy the gastric pouch is made mostly of gastric cardia. H. pylori typically resides in the gastric remnant, not the pouch, making breath test and pouch biopsy less effective. Serology is difficult to interpret since it often remains positive even after H. pylori eradication.
- Fecal antigen in standard of care in this patient population.
A 19-year-old man reports predictable symptoms of watery, itchy eyes, and perioral numbness and tingling after eating pizza, waffles, and pancakes. His presentation is most consistent with what diagnosis?
A. Celiac disease
B. Non-celiac gluten sensitivity
C. Wheat allergy
D. Irritable bowel syndrome
- Celiac disease, a small intestine autoimmune enteropathy, may be associated with abdominal pain, bloating, diarrhea, weight loss, and vitamin deficiencies, however, it is not associated with classic allergic symptoms of itchy, watery eyes, and perioral numbness.
- Non-celiac gluten sensitivity (NCGS) describes individuals who develop intestinal and extra-intestinal symptoms similar to celiac disease after ingesting gluten-containing products. However, in NCGS serologic tests and duodenal biopsies are not consistent with the diagnosis of celiac disease. These symptoms resolve with the elimination of gluten from the diet. Patients with NCGS do not develop the allergic symptoms reported by the patient.
- Wheat allergy results from an adverse type-2 helper T-Cell immunologic reaction to wheat exposures. Symptoms develop shortly after ingesting wheat and include signs of an allergic response (nasal congestion, perioral numbness, itchy eyes, wheezing, shortness of breath). The prevalence is higher in children (2-9%) than in adults (0.5-3%). Anaphylaxis can occur with extreme wheat allergy reactions, so patients should be evaluated by an allergist and should have an epinephrine pen available at all times.
- Although IBS patients report a number of symptoms, allergic type symptoms after the ingestion of wheat is not characteristic of IBS.
A 28-year-old woman presents to the emergency department with a recurrent episode of severe abdominal pain, nausea, and vomiting. She has been having similar episodes twice a year for the last 6 years. All episodes were similar, with the sudden development of severe, diffuse abdominal pain that caused her to come to the hospital. She typically presents with agitation and requests intravenous narcotics for pain relief. During previous episodes, laboratory testing and computed tomography of the abdomen was unremarkable. She had normal abdominal sonography, endoscopy, and colonoscopy during symptom-free intervals.
Physical examination revealed an anxious, uncomfortable young woman. She was afebrile, pulse was 120 and regular, and BP was 160/100. Her abdomen was slightly distended and bowel sounds were reduced, but she had no direct or rebound tenderness. Neurologic examination showed evidence of mild proximal muscle weakness. Laboratory testing showed a normal complete blood count. Complete metabolic profile was normal except for a serum sodium concentration of 130 mmol/L. Serum lipase was normal. What is the most appropriate diagnostic test to obtain next?
A. Plain radiograph of abdomen (KUB film)
B. Magnetic resonance cholangiopancreatography
C. Drug screen for cannabinoids
D. Spot urine for porphobilinogen and creatinine
E. Urinalysis
- Several conditions may present with episodic symptoms of severe abdominal pain, nausea and vomiting. These include cyclic vomiting syndrome (CVS), cannabis hyperemesis syndrome, and acute porphyria. Pain can occur with all of these syndromes; vomiting is more prominent with CVS and cannabis hyperemesis, but severe pain is prototypical with porphyria.
- Visceral problems such as cholelithiasis, pancreatitis, volvulus, and kidney stones may also produce intermittent symptoms, but usually do not present as dramatically as the problems mentioned earlier. This patient is having an attack of acute porphyria which is characterized by tachycardia and hypertension, pain out of proportion to abdominal tenderness, proximal muscle weakness, and hyponatremia.
- Porphobilinogen (PBG) concentration in urine is substantially elevated during acute attacks and is the best choice to confirm this diagnosis rapidly. If PBG levels are high, intravenous hemin therapy can be started, which usually stops the attack. The type of acute porphyria can be established by measuring porphyrin levels, activities of enzymes in the heme synthesis pathway, and genetic testing. Once the diagnosis is established, attacks can be treated promptly without the need for further diagnostic testing.
Which of the following has been a reported complication of STW-5 (also known as Iberogast)?
A. Leukoencephalopathy
B. Hepatotoxicity
C. Cardiac arrhythmias
D. Pulmonary fibrosis
E. Nephrocalcinosis
- STW-5, or Iberogast, has been used in the management of functional dyspepsia and irritable bowel syndrome. It is made up of 9 ingredients, including: extracts of bitter candytuft, peppermint herb, angelica root, milk thistle fruit, celandine herb, caraway fruit, licorice root, balm leaf, and chamomile flower.
- In 2016, there was a first report of hepatotoxicity requiring transplant (and found to be a “probable” association with the supplement) in a 37-year-old man who had been on STW-5 for 2 weeks.
- Greater celandrine extract, which is one of the ingredients in STW-5, has been linked to 16 cases of hepatotoxicity in Europe.
- The hepatotoxicity has been deemed to likely be an idiosyncratic due to a metabolic subtype, although a few patients have been found to have autoimmune antibodies triggered as well.
A 63-year-old woman was seen in clinic for diarrhea that has been present for 18 months. She had no recent travel nor medication changes in the interval preceding onset of symptoms. She reported some abdominal cramping, nocturnal stools, and a 15-lb weight loss. She has a history of hyperlipidemia, hypertension, depression, and chronic reflux symptoms. She forgets to bring her medication list to the appointment. Complete blood count, C-reactive protein, thyroid stimulating hormone level, and IgA tissue transglutaminase are normal. EGD with small bowel biopsies reveals villous atrophy, increased intraepithelial lymphocytes, chronic inflammation in the lamina propria, and collagen deposition. Which of the following medication classes may be related to the patient’s symptoms and findings?
A. Statin
B. Beta-blocker
C. Selective serotonin reuptake inhibitor
D. Angiotensin receptor blocker
E. Proton pump inhibitor
- Olmesartan medoxomil (prodrug of olmesartan), is an angiotensin-2 receptor antagonist/blocker which was approved in the United States in 2002 (2003 in Europe) for hypertension. The first cases of olmesartan-induced celiac-like enteropathy were reported in 2012 by Mayo Clinic, with 22 patients who were serologically negative for celiac disease, referred for “refractory sprue,” with these patients each on olmesartan (Benicar) for hypertension. In July of 2013, the FDA came out with a warning that olmesartan medoxomil can lead to intestinal problems known as sprue-like enteropathy.
- After the Mayo series was reported, 2 additional series were published, 1 out of France (2014) with 36 patients and the other out of Spain (2015) with 11 patients. Between these 3 studies, it was noted that the median age of patients was 69.5-72 years, on the drug for a mean of 2.3-3.1 years, with 61-100% of those tested being positive for HLA DQ2 or 8. All patients had diarrhea, while 45-75% had abdominal pain, and many with significant weight loss. Collagen deposition was noted on duodenal biopsies in a number of patients. A 2013 study that looked into the etiology of 72 cases of seronegative enteropathy noted that 19 such cases were medication-related, with 16 of 19 on olmesartan, and 11 of the 16 patients noted to have collagen deposition on histology. The finding of collagen deposition on small bowel biopsies along with features of enteropathy should lead to careful medication review.
A 29-year-old man presents to clinic for a follow-up evaluation for celiac disease, which was diagnosed 6 months ago during the work-up for microcytic anemia. At the time of the work-up, IgA tissue transglutaminase antibody (TTG) was markedly positive, and small bowel biopsies revealed total villous atrophy, increased intraepithelial lymphocytes, and chronic inflammatory changes in the lamina propria. He was referred to a dietitian, and has followed a strict gluten-free diet since, and was started on iron replacement. Lately, he has noticed lower extremity weakness when playing in his weekly soccer league. Laboratory studies show a persistent microcytic anemia, with a normal serum ferritin. His IgA TTG is now normal. Which of the following is the best next step?
A. Obtain magnetic resonance imaging of the brain.
B. Check serum chromium level.
C. Order electromyography.
D. Check serum copper level.
E. Initiate intravenous iron replacement.
- In patients with celiac disease, a variety of vitamin and micronutrient deficiencies may occur.
- Although iron deficiency is the most common cause of microcytic anemia in those with celiac disease, this patient has a persistent microcytic anemia despite evidence of adequate iron stores, and copper deficiency needs to be considered.
- Copper deficiency can cause a microcytic anemia and a rare myeloneuropathy, and has been reported to occur in patients with celiac disease at rates that vary between 6-33%. Since copper deficiency may occur without anemia, levels should be checked in newly diagnosed patients to prevent neurologic sequelae, which could be irreversible.
- While an MRI of the brain may show abnormal signal in patients with copper deficiency (in both the brain and spinal cord), it would not be the most cost-effective or direct approach to the diagnosis.
- Chromium deficiency can cause a peripheral neuropathy and hyperglycemia, but does not typically cause anemia.
- Similar to the MRI, an electromyography can help diagnose a neuropathy or suggest a myelopathy, but the findings would not be specific to copper deficiency, and doing this next may delay the diagnosis and effective treatment.
- Intravenous iron would not be appropriate given that the patient has a normal serum ferritin, so alternate causes of microcytic anemia need to be considered.
The low-FODMAP diet has been shown to improve IBS symptoms in a number of studies. However, the restrictive nature of the diet has raised concerns over possible micronutrient deficiencies. These concerns were confirmed in a recent prospective study comparing the low-FODMAP diet to a modified NICE diet. Specifically, deficiencies in riboflavin, calcium, vitamin B6, and retinol were identified in patients on the low-FODMAP diet. This highlights the need to use the low-FODMAP diet for a brief period of time (4-6 weeks; a period of dietary restriction), followed by gradual reintroduction of foods until symptoms recur.
