A 41 year old man with diarrhea weight loss and

This preview shows page 42 - 45 out of 54 pages.

A 41-year-old man with diarrhea, weight loss, and epigastric discomfort undergoes endoscopic examination, revealing diffusely thickened rugal folds, suggestive of the linitis plastica-type adenocarcinoma. Biopsy reveals no cancer, but a dramatic hyperplasia of superficial mucous cells with scant gastric glands. As a consequence of this condition, this man may be losing excessive amounts of which of the following from his digestive tract? A. Carbohydrates B. Chloride C. Fat D. Protein E. Water 42
Explanation: The correct answer is D. This patient has Menetrier's disease, also known as protein-losing gastroenteropathy. Increased mucus production in Menetrier's disease leads to protein losses from excessive gastric secretions, and may cause hypoalbuminemia and peripheral edema. Absorption of carbohydrates (choice A), which occurs in the small intestine, is unimpaired in Menetrier's disease. Menetrier's disease is associated with deficient production of gastric acid, so chloride loss (choice B) would be unlikely. This is in marked contrast to hypertrophic-hypersecretory gastropathy and the Zollinger- Ellison syndrome, in which there is hyperplasia of chief cells (rather than atrophy, as in Menetrier's disease). Dietary fat loss (choice C) is generally due to enteric malabsorption, such as that which occurs in celiac disease or cystic fibrosis. Gastric mucus is poor in fats, and no appreciable fat loss accompanies Menetrier's disease. Fluid losses (choice E) due to mucus overproduction in Menetrier's disease are reabsorbed in the gut. Menetrier's disease does not cause dehydration. Examination of an autopsy specimen from a Mexican immigrant demonstrates a heart with massive dilation of the aortic root and adjacent aortic arch. Opening the aorta reveals a smooth interior wall without obvious lesions. If a histological section through the aortic wall is made, which of the following would most likely be seen? A. A heavy eosinophilic infiltrate B. Fibrinoid necrosis with a neutrophilic infiltration C. Focal fragmentation of elastic elements D. Obliterative endarteritis of the vasa vasorum E. Ring-like calcification of the vessel media Explanation: The correct answer is D. Massive dilation of the aortic root with an absence of atherosclerotic vessel lesions strongly suggests a syphilitic aneurysm. These aneurysms are a manifestation of tertiary syphilis and have become very uncommon now, probably due to a combination of deliberate therapy and therapy of undiagnosed 43
disease when antibiotics are given for some other condition. The histologic hallmark of the syphilitic aneurysm is a plasma cell lesion of the small blood vessels (the vasa vasorum) that supply the aorta, and eventually obliterate the small vessel lumina. Choice A is a feature of Churg-Strauss syndrome, which is a variant of polyarteritis nodosa that involves vessels smaller than the aorta.

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture