A 50-year-old man presents with fatigue, arthralgia, and darkening of the skin. Laboratory tests reveal elevated liver enzymes and high serum ferritin levels. What is the most likely diagnosis?

Correct Answer: B

Rationale: The correct answer is B: Hemochromatosis. In this case, the patient's symptoms of fatigue, arthralgia, darkening of the skin, elevated liver enzymes, and high serum ferritin levels point towards iron overload disorder. Hemochromatosis is a genetic condition characterized by excessive absorption and accumulation of iron in various organs, leading to liver damage and skin pigmentation. Wilson's disease (A) presents with copper accumulation, not iron. Alpha-1 antitrypsin deficiency (C) primarily affects the lungs and liver, not causing iron overload. Autoimmune hepatitis (D) does not typically present with elevated ferritin levels.

Correct Answer: A

Rationale: The correct answer is A: Ulcerative colitis. This chronic inflammatory condition affects the colon and rectum, leading to symptoms like abdominal pain, diarrhea, and rectal bleeding. The patient's recurrent episodes and history of similar symptoms point towards ulcerative colitis. Irritable bowel syndrome (choice B) typically presents with abdominal pain, bloating, and changes in bowel habits but not rectal bleeding. Celiac disease (choice C) presents with gastrointestinal symptoms after consuming gluten. Diverticulitis (choice D) presents with localized abdominal pain and fever due to inflammation or infection of the diverticula, not typically with rectal bleeding.

Correct Answer: C

Rationale: The most likely diagnosis for a 65-year-old man with weight loss, jaundice, palpable mass in the right upper quadrant, elevated bilirubin, and alkaline phosphatase levels is pancreatic cancer. This is because the symptoms and findings are classic for pancreatic cancer, which commonly presents with obstructive jaundice due to compression of the common bile duct by the tumor. Weight loss is also a common symptom of pancreatic cancer. Gallstones typically present with acute episodes of biliary colic, not a palpable mass. Hepatitis typically presents with elevated liver enzymes, but not a palpable mass. Primary biliary cirrhosis presents with chronic cholestasis and autoimmune features, not a palpable mass.

Correct Answer: A

Rationale: The most likely diagnosis for a 40-year-old woman presenting with fatigue, polyuria, polydipsia, hyperglycemia, and ketonuria is Type 1 diabetes mellitus. 1. Age: Type 1 diabetes commonly presents at a younger age. 2. Symptoms: Polyuria, polydipsia, fatigue are classic symptoms of uncontrolled diabetes. 3. Laboratory tests: Hyperglycemia and ketonuria indicate insulin deficiency. 4. Clinical presentation: Presence of ketonuria suggests metabolic derangement due to lack of insulin. In summary, Type 1 diabetes is the correct choice due to the age of the patient, symptoms, laboratory findings, and clinical presentation. Diabetes insipidus (choice C) presents with polyuria and polydipsia but lacks hyperglycemia and ketonuria. Type 2 diabetes (choice B) typically presents at an older age and rarely with ketonuria. Hyperthyroidism (choice D)

Correct Answer: A

Rationale: The most likely diagnosis is A: Primary biliary cirrhosis. Rationale: 1. Pruritus, jaundice, and xanthomas are classic symptoms of cholestatic liver disease. 2. Elevated cholesterol and alkaline phosphatase levels are characteristic of primary biliary cirrhosis. 3. Primary biliary cirrhosis is an autoimmune disease affecting small bile ducts, leading to liver damage. 4. Primary sclerosing cholangitis (B) presents with similar symptoms but typically affects larger bile ducts. 5. Gallstones (C) could cause jaundice but would not explain the elevated cholesterol levels. 6. Pancreatic cancer (D) may present with jaundice but is less likely given the specific lab findings.