A 45-year-old man with diabetes mellitus is admitted to the intensive care unit due to community-acquired pneumonia, septic shock, and respiratory failure. Two days ago, he developed fever, productive cough, and shortness of breath that has progressively worsened. The patient is intubated and placed on mechanical ventilation. He is also started on intravenous fluids, broad-spectrum antibiotics, and a norepinephrine infusion. On the third day of hospitalization, hemoglobin level drops from 14 g/dL to 12 g/dL. Nasogastric suctioning reveals bright red blood. This patient's bleeding is most likely a result of which of the following processes?

Question

A 45-year-old man with diabetes mellitus is admitted to the intensive care unit due to community-acquired pneumonia, septic shock, and respiratory failure.  Two days ago, he developed fever, productive cough, and shortness of breath that has progressively worsened.  The patient is intubated and placed on mechanical ventilation.  He is also started on intravenous fluids, broad-spectrum antibiotics, and a norepinephrine infusion.  On the third day of hospitalization, hemoglobin level drops from 14 g/dL to 12 g/dL.  Nasogastric suctioning reveals bright red blood.  This patient's bleeding is most likely a result of which of the following processes?

Quizplus · Accepted Answer

11ec160b_3960_81b3_9249_53c714737c58_MD0001_00 Stress-related mucosal disease is characterized by acute gastric mucosal defects that develop in response to severe physiologic stress (eg, shock, extensive burns, sepsis, severe trauma, intracranial injury). Patients often have multiple, small (<1 cm), circular lesions in the stomach, ranging from superficial erosions to full-thickness ulcers. Ulcers may perforate or bleed, as in this patient. The pathogenesis of these ulcers most often involves impaired mucosal protection due to local ischemia caused by systemic hypotension and splanchnic vasoconstriction. Ulcers arising in the proximal duodenum in association with severe trauma/burns are called Curling ulcers. Ulcers arising in the esophagus, stomach, or duodenum in patients with intracranial injury are particularly prone to perforation and are called Cushing ulcers. Cushing ulcers are a consequence of direct vagus nerve stimulation caused by elevated intracranial pressure, resulting in acetylcholine release and hypersecretion of gastric acid. (Choice A) Chronic gastritis with antral sparing is characteristic of autoimmune gastritis. CD4+ T cell-mediated parietal cell destruction causes impaired gastric acid and intrinsic factor secretion, resulting in achlorhydria and pernicious anemia, respectively. (Choice B) Zollinger-Ellison syndrome is caused by a gastrin-secreting tumor (gastrinoma) that is usually located in the small intestine or pancreas. Patients classically have multiple peptic ulcers that may involve the distal duodenum and are more likely to respond poorly to therapy. (Choice C) Granulomatous gastritis is most often idiopathic but may be associated with Crohn disease, sarcoidosis, or mycobacterial infection. It is characterized by intramucosal epithelioid granulomas that cause narrowing of the antrum secondary to transmural inflammation, which can result in gastric outlet obstruction. (Choice D) Peptic ulcers in the stomach or duodenum are most commonly due to Helicobacter pylori infection or nonsteroidal anti-inflammatory drug use. H pylori infection is also associated with chronic antral-predominant gastritis. (Choice E) Gastric adenocarcinoma can occur as the intestinal subtype (ie, bulky mass composed of glandular structures) or diffuse subtype (ie, gross stomach wall thickening with signet-ring cells on microscopy). Risk factors for gastric adenocarcinoma include chronic gastritis, cigarette smoking, H pylori infection, and a diet high in salt/nitrosamines. Educational objective: Stress-related mucosal disease is usually caused by local ischemia in the setting of severe physiologic stress (eg, shock, extensive burns, sepsis, severe trauma). Ulcers arising in the setting of severe trauma/burns are called Curling ulcers. Ulcers arising from intracranial injury are caused by direct vagal stimulation and are called Cushing ulcers. __________ References: Stress-related mucosal disease in the intensive care unit: an update on prophylaxis. (http://www.ncbi.nlm.nih.gov/pubmed/17473539) Stress ulceration: prevalence, pathology and association with adverse outcomes. (http://www.ncbi.nlm.nih.gov/pubmed/25029573)

A 45-Year-Old Man with Diabetes Mellitus Is Admitted to the Intensive