The answer – hypokalemic metabolic alkalosis and hypocalcemia

To recap the story: 70+ year old man with recent admission for pneumonia.  Discharge on clindamycin and levofloxacin.  Now with progressive weakness, fatigue, tingling and confusion. 142 98 12 256 2.5 32 1.4 6.5 albumin 2.8 pH 7.53 pCO2 39 pO2 69 HCO3 32 What happened in the past 3 weeks?  What diagnostic tests do you want, and what questions do you want to ask? Answer: He had some loose stools, but negative C diff. I asked the question about his previous labs – they had been normal.  Hypokalemic metabolic alkalosis and hypocalcemia made me think of hypomagnesemia.  Then I wondered why he would have low magnesium.  In fact his magnesium level was very low.  He did not have alcohol abuse. So I asked if he took a PPI.  In fact, they had started a PPI at his last hospitalization.  Repleting his magnesium allowed correction of his potassium and calcium and resolution of his symptoms. Here is an article about this phenomenon.
Source: DB's Medical Rants - Category: Internal Medicine Authors: Tags: Acid-Base & Lytes Attending Rounds Source Type: blogs