Type IV renal tubular acidosis presenting as dyspnea in two older patients taking angiotensin-converting enzyme inhibitors.

Abstract

The evaluation of dyspnea most often leads to a cardiac or pulmonary diagnosis. In the elderly, however, the cause is commonly multifactorial. The emergency physician should always consider noncardiopulmonary etiologies when treating such patients. We present 2 cases of new-onset type IV renal tubular acidosis (RTA) in older patients taking lisinopril who presented to the emergency department as dyspnea. Both patients had chronic cardiopulmonary illnesses and were initially diagnosed as having either congestive heart failure, asthma exacerbations, or both. The laboratory results for RTA are specific and the diagnosis can be made in the ED.