FIRST AID FOR®
THE
USMLE
STEP 2 CS
Fifth Edition
TAO LE, MD, MHS
Associate Clinical Professor of Medicine and Pediatrics
Chief, Section of Allergy and Immunology
Department of Medicine
University of Louisville
VIKAS BHUSHAN, MD
Diagnostic Radiologist
MAE SHEIKH-ALI, MD
Associate Professor of Medicine
Associate Program Director, Endocrinology Fellowship Program
Division of Endocrinology, Diabetes and Metabolism
University of Florida College of Medicine–Jacksonville
KACHIU CECILIA LEE, MD, MPH
Clinical and Research Fellow
Wellman Center for Photomedicine
Department of Dermatology
Massachusetts General Hospital, Harvard Medical School
New York / Chicago / San Francisco / Lisbon / London / Madrid / Mexico City
Milan / New Delhi / San Juan / Seoul / Singapore / Sydney / Toronto
,Copyright © 2014, 2012, 2010, 2007, 2004 by Tao Le. All rights reserved. Except as permitted under the United States Copyright Act of 1976, no part of this publication may
be reproduced or distributed in any form or by any means, or stored in a database or retrieval system, without the prior written permission of the publisher, with the exception
that the program listings may be entered, stored, and executed in a computer system, but they may not be reproduced for publication.
ISBN: 978-0-07-180933-7
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, DEDICATION
To the contributors of this and past editions, who took time to share their
experience, advice, and humor for the benefit of future physicians.
and
To our families, friends, and loved ones, who supported us in the task of
assembling this guide.