A 4-year-old boy presents with chronic hemolytic anemia, scleral icterus, and splenomegaly. Vital signs: HR 110/min, RR 22/min, BP 95/60 mmHg, temperature 37.2°C. Laboratory studies reveal hemoglobin 7.2 g/dL with echinocytes on peripheral smear. Red blood cell ATP concentration is markedly decreased. Reticulocyte count is elevated at 8%. He denies recent infections or medications. Which metabolic consequence is most likely present in these erythrocytes?
- A)Decreased NADPH production causing Heinz bodies
- B)Increased 2,3 bisphosphoglycerate causing a right shift of the oxygen dissociation curveGABARITO
- C)Decreased 2,3 bisphosphoglycerate causing increased oxygen affinity
- D)Accumulation of porphobilinogen causing neuropathy
- E)Increased reduced glutathione causing resistance to oxidant injury
Explicação
Increased 2,3 bisphosphoglycerate causing a right shift of the oxygen dissociation curve is correct. Pyruvate kinase deficiency decreases ATP generation in erythrocytes, causing membrane failure and chronic hemolysis. Upstream glycolytic intermediates accumula... Ver explicação completa e trilha adaptativa →