A 34-year-old man presents with 5-month history of weakness and fatigue. There is no history of drug or alcohol abuse. CBC shows megaloblastic anemia and a normal reticulocyte count. Fuher laboratory studies reveal vitamin B12 deficiency. Anemia in this patient is most likely caused by which of the following?
Acute erosive gastritis
Autoimmune gastritis
Helicobacter pylori gastritis
Menetrier disease
Type A/ Autoimmune gastritis: -Site : Fundus & body of stomach - Damage : Parietal cells resulting in: Achlorhydria - |G-cell stimulation - |Gastrin levels -| Neuroendocrine tumor Intrinsic factor deficiency - Malabsorption of vitamin B12 - Megaloblastic anemia /Pernicious anemia
Systemic Pathology