1.
A 32 year-old man was admitted 7 months after the acute onset of severe diarrhoea. He later underwent colonic resection. The microphotograph below shows the histological features. What is the most likely diagnosis?
Correct Answer
C. Ulcerative colitis
Explanation
The most likely diagnosis based on the given information and histological features is ulcerative colitis. This is supported by the patient's symptoms of severe diarrhea and the need for colonic resection. Ulcerative colitis is a form of inflammatory bowel disease that primarily affects the colon and rectum, causing inflammation and ulcers in the lining of the digestive tract. This aligns with the histological features shown in the microphotograph.
2.
Below is the line diagram of microscopic appearance of a bowel disease. The features shown are characteristic of which of the following conditions?
Correct Answer
B. Crohns disease
Explanation
The given line diagram of the microscopic appearance of a bowel disease is characteristic of Crohn's disease. Crohn's disease is a type of inflammatory bowel disease that can affect any part of the digestive tract, from the mouth to the anus. The diagram shows features that are consistent with the inflammation and damage seen in Crohn's disease, such as thickening of the intestinal wall, presence of ulcers, and areas of inflammation.
3.
Below is the image of gross specimen resected from a patient with chronic diarrhoea and arthritis. What is the most likely diagnosis?
Correct Answer
B. Crohns disease
Explanation
The image shows a gross specimen resected from a patient with chronic diarrhea and arthritis. Crohn's disease is the most likely diagnosis because it is a chronic inflammatory bowel disease that can affect any part of the gastrointestinal tract, including the colon. It is characterized by transmural inflammation, which can lead to symptoms such as diarrhea, abdominal pain, and arthritis. The image does not show any signs of intestinal perforation, ulcerative colitis, or membranous enterocolitis, making Crohn's disease the most appropriate diagnosis.
4.
The below image is the resected colon from a 56 year-old male presented with chronic constipation and recent hematochezia of two weeks duration. What is the most likely diagnosis?
Correct Answer
D. Diverticulitis
Explanation
The most likely diagnosis for the resected colon in a 56-year-old male with chronic constipation and recent hematochezia is diverticulitis. Diverticulitis is characterized by the inflammation or infection of small pouches called diverticula that form in the lining of the colon. This condition commonly presents with symptoms such as abdominal pain, changes in bowel habits, and rectal bleeding. Given the patient's symptoms and the presence of diverticula in the resected colon, diverticulitis is the most probable diagnosis.
5.
A mother brings her 3 month-old boy to emergency presenting with progressive abdominal distension, poor feeding and difficulty in passing stool. A contrast radiograph is shown. What is the most likely diagnosis?
Correct Answer
A. Hirschprung disease
Explanation
The most likely diagnosis in this case is Hirschprung disease. This condition is characterized by a lack of ganglion cells in the distal part of the colon, leading to functional obstruction. The symptoms described, including abdominal distension, poor feeding, and difficulty passing stool, are consistent with this diagnosis. Additionally, the contrast radiograph may show a transition zone between the dilated proximal colon and the narrowed distal colon, which is a characteristic finding in Hirschprung disease. Meconium plug syndrome, anorectal malformation, and cystic fibrosis associated with meconium ileus are all possible differentials, but Hirschprung disease is the most likely based on the given information.
6.
An 80 year-old male presents with six weeks history of diarrhoea with weight loss. He does not have a history of rectal bleeding or mucous discharge. About 8 weeks before admission he had been treated for a chest infection by his GP with broad spectrum antibiotics. He had flexible sigmoidoscopy showing the following picture. What is the most likely diagnosis?
Correct Answer
C. Pseudomembranous colitis
Explanation
Based on the given information, the most likely diagnosis for the patient is pseudomembranous colitis. The patient's symptoms of diarrhea with weight loss, along with the history of recent antibiotic use, are consistent with this condition. Pseudomembranous colitis is caused by an overgrowth of Clostridium difficile bacteria in the colon, which can occur after antibiotic treatment. The flexible sigmoidoscopy image is also characteristic of pseudomembranous colitis, showing the presence of yellowish plaques or pseudomembranes on the surface of the colon.
7.
A 27 year-old female complains of long standing symptoms of diarrhoea, flatulence, weight loss and fatigue. On Endoscopy the small intestine mucosa appears flat. Biopsy demonatrates diffuse enteritis with marked atrophy of villi. The surface epithelium shows loss of microvilus brush border and increased number of intraepithelial lymphocytes. What is the most likely diagnosis?
Correct Answer
D. Celiac disease
Explanation
The most likely diagnosis for this patient is celiac disease. Celiac disease is an autoimmune disorder triggered by the ingestion of gluten, a protein found in wheat, barley, and rye. The symptoms described, such as chronic diarrhea, weight loss, and fatigue, are commonly seen in celiac disease. The endoscopic findings of flat mucosa and atrophy of villi, along with the loss of microvillus brush border and increased intraepithelial lymphocytes, are characteristic of celiac disease. Crohn's disease, Whipple's disease, ulcerative colitis, and irritable bowel syndrome do not typically present with these specific findings.
8.
An 8 month-old previously healthy infant girl develops a watery diarrhoea that lasts for 1 week. The infant has a mild fever during the illness but has no abdominal pain or swelling. On physical examination, her temperature is 37 degrees celsius. A stool sample is negative for occult blood, ova or parasites. Her parents are told to give her plenty of fluids, and she recovers fully. Which of the following organisms is most likely to produce these findings?
Correct Answer
D. Rotavirus
Explanation
Rotavirus is the most likely organism to produce these findings. Rotavirus is a common cause of viral gastroenteritis in infants and young children. It typically presents with watery diarrhea that lasts for about a week, along with a mild fever. Abdominal pain and swelling are usually absent. The stool sample is negative for occult blood, ova, or parasites. Treatment involves supportive measures such as giving plenty of fluids, and the prognosis is usually good, with full recovery.
9.
A 68 year-old woman presented with a long history of cholelithiasis and chronic cholecystitis. One week before her last hospital admission, the patient developed jaundice with a markedly increased conjugated bilirubin in the serum. The gallbladder was removed. A microscopic section of the gallbladder is shown in the following image. The findings are consistent with which of the following?
Correct Answer
C. Adenocarcinoma of the gallbladder
Explanation
The microscopic section of the gallbladder shows findings consistent with adenocarcinoma of the gallbladder. This is indicated by the presence of malignant cells in the tissue, which is characteristic of adenocarcinoma. The patient's history of cholelithiasis and chronic cholecystitis, along with the development of jaundice and elevated conjugated bilirubin, further support the diagnosis of adenocarcinoma. Cholesterolosis, gangrenous cholecystitis, squamous cell carcinoma, and chronic cholecystitis would typically present with different histological features and clinical manifestations.
10.
A 53 year-old woman complains of acute bloody diarrhoea and severe abdominal pain. She was recently treated with broad-spectrum antibiotics for community-acquired pneumonia. A FBC shows a WBC count of 24,000/µL. The patient subsequently develops septic shock and dies. A portion of her colon, shown in the below image, is shown at autopsy. These findings are typical of which of the following gastrointestinal diseases?
Correct Answer
D. Pseudomembranous colitis
Explanation
The given answer is pseudomembranous colitis. This is suggested by the patient's recent treatment with broad-spectrum antibiotics, which can disrupt the normal gut flora and allow for overgrowth of Clostridium difficile bacteria. This can lead to the development of pseudomembranous colitis, characterized by acute bloody diarrhea, severe abdominal pain, and a high white blood cell count. The autopsy findings, which are not described in the question, would likely show the presence of pseudomembranes in the colon.