After three days of flu-like symptoms, a patient is feeling unsteady on her feet and dizzy when she attempts to stand up. During her illness she has eaten very little and has had frequent emesis. Blood tests reveal an arterial pH of 7.5 and a partial pressure of carbon dioxide of 53 mm Hg. What is the most likely etiology of this acid-base disturbance?
(A) Consumption of antacids
(B) Decreased hydrogen excretion in the distal tubule
© Increased bicarbonate reabsorption by the proximal tubule
(D) Production of ADH
(E) Volume depletion and increased hydrogen excretion in the distal tubule
ans:(E) Volume depletion and increased hydrogen excretion in the distal tubule