Alluru S. Reddi an Essential Q & a Study Guide
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Alluru S. Reddi Absolute Nephrology Review An Essential Q & A Study Guide 123 Absolute Nephrology Review Alluru S. Reddi Absolute Nephrology Review An Essential Q & A Study Guide Alluru S. Reddi Professor of Medicine Chief, Division of Nephrology and Hypertension Rutgers New Jersey Medical School Newark, NJ, USA ISBN 978-3-319-22947-8 ISBN 978-3-319-22948-5 (eBook) DOI 10.1007/978-3-319-22948-5 Library of Congress Control Number: 2015959706 Springer Cham Heidelberg New York Dordrecht London # Springer International Publishing Switzerland 2016 This work is subject to copyright. All rights are reserved by the Publisher, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed. The use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. The publisher, the authors and the editors are safe to assume that the advice and information in this book are believed to be true and accurate at the date of publication. Neither the publisher nor the authors or the editors give a warranty, express or implied, with respect to the material contained herein or for any errors or omissions that may have been made. Printed on acid-free paper Springer International Publishing AG Switzerland is part of Springer Science+Business Media (www.springer.com) Preface The purpose of writing this book is to allow the nephrology fellow and the practicing nephrologist to learn nephrology as a whole, in the form of questions and answers. This avoids having these clinicians read a lengthy nephrology textbook. The questions are based on a review of recent information obtained from several journals and standard textbooks and also from the author’s clinical experience. The questions in each chapter are geared to cover the basics of physiology, pathogenesis, and treatment strategies of a clinical problem. Writing a pertinent question is more difficult than writing a book chapter. Each question took a lengthy time to write and even more time to provide a satisfactory answer. I strongly believe that this review book would help each graduating nephrology fellow and practicing nephrologist to pass their board examination. This book would not have been completed without the help of many students, house staff, and colleagues, who made me learn nephrology and manage patients appropriately. They have been the powerful source of my knowledge, and I am grateful to all of them. I am extremely thankful and grateful to my family for their immense support and patience. My special thanks go to Surya V. Seshan, MD, who provided all the photomicrographs included in Chapter 2. Her contribution to our Nephrology Fellowship Program and to this review book is gratefully acknowledged and recognized. Finally, I extend my thanks to the staff at Springer, particularly Gregory Sutorius and Michael Koy, for their constant support, help, and advice. Constructive criticism for improvement of the book is gratefully acknowledged. Newark, NJ Alluru S. Reddi v Contents 1 Fluids, Electrolytes, and Acid–Base Disorders ............................................. 1 2 Glomerular, Tubulointerstitial, and Vascular Diseases ...................................... 57 3 Acute Kidney Injury and Critical Care Nephrology ........................................ 155 4 Chronic Kidney Disease .............................................................. 195 5 Disorders of Mineral Metabolism and Nephrolithiasis ...................................... 231 6 Hypertension ...................................................................... 269 7 Renal Pharmacology ................................................................ 313 8 Genetic Diseases and Pregnancy ....................................................... 341 9 Hemodialysis ...................................................................... 371 10 Peritoneal Dialysis .................................................................. 399 11 Transplantation .................................................................... 421 Index ............................................................................... 477 vii Chapter 1 Fluids, Electrolytes, and Acid–Base Disorders 1. A 36-year-old woman is admitted for dizziness, weakness, poor appetite, fatigue, and salt-craving for 4 weeks. She has history of asthma, and not on any medications. She has a family history of type 1 diabetes and hypothyroidism. On admission, her blood pressure (BP) is 100/60 mmHg with a pulse rate of 100 (sitting), and 80/48 mmHg with a pulse rate of 120 beats/min (standing). Her temperature is 99.6 F. Laboratory values are as follows: Naþ ¼ 124mEq=L Creatinine ¼ 1:8mg=dL Kþ ¼ 6:1mEq=L Glucose ¼ 50mg=dL ClÀ ¼ 114mEq=L Hemoglobin ¼ 13g=dL À HCO3 ¼ 20mEq=L Hematocrit ¼ 40% BUN ¼ 42mg=dL Urinary Naþ ¼ 60mEq=L Based on the above history and laboratory values, which one of the following fluids is APPROPRIATE in addition to pertinent hormone administration? A. 5 % Dextrose in water (D5W) B. 5 % Albumin C. Ringer’s lactate (lactated Ringer solution) D. Normal (0.9 %) saline E. 0.45 % (Half-normal) saline The answer is D The orthostatic BP and pulse changes suggest volume depletion. Hyponatremia, hyperkalemia, elevated BUN and creatinine, hypoglycemia, and high urinary Na+ excretion suggest adrenal insufficiency (Addison’s disease), which is due to glucocorticoid and mineralocorticoid deficiency. Her signs and symptoms are related to volume depletion and electrolyte abnormalities. Hypotension is related to loss of both Na+ and water caused by deficiency of the above hormones. In addition to administration of hydrocortisone and fludrocortisones, the patient needs normal saline adminis- tration to improve total body volume (D is correct). Both volume repletion and hormone treatment improve BP and electrolytes. D5W may improve hyperkalemia and glucose, but not adequate to improve volume (A is incorrect). 5 % albumin may expand volume, but is not indicated in this patient (B is incorrect). Ringer’s lactate may exacerbate hyperkalemia and hypercalcemia (about 10 % of patients with Addison’s disease have hypercalcemia) with little effect on hyponatremia. Thus, C is incorrect. Half-normal saline is not adequate to replete the entire fluid in this patient (E is incorrect). Suggested Reading Ten S, New M, Maclaren N. Addison’s disease 2001. J Clin Endocrinol Metab 86:2909–2922, 2001. Sarkar SB, Sarkar S, Ghosh S, et al. Addison’s disease. Contemp Clin Dent 3:484–486, 2012. # Springer International Publishing Switzerland 2016 1 A.S. Reddi, Absolute Nephrology Review, DOI 10.1007/978-3-319-22948-5_1 2 1 Fluids, Electrolytes, and Acid–Base Disorders 2. It is always important to know how much infused crystalloid or colloid will remain in the intravascular compartment to improve volume status and hemodynamic status. Which one of the following fluids contributes MOST to the intravascular compartment? A. D5W B. Half-normal saline C. Normal saline D. Ringer’s lactate E. C and D The answer is E In order to answer the question, it is important to remember the percentage of total body water and its distribution in various fluid compartments. In a 70 kg man with lean body mass, the total body water accounts for 60 % of body weight (42 L), and two-thirds of this water (i.e., 28 L) is in the intracellular fluid (ICF) and one-third (i.e., 14 L) is in the extracellular fluid (ECF) compartment (Fig. 1.1). Of these 14 L of ECF water, 3.5 L (25 %) is present in the intravascular and 11.5 L (75 %) in the interstitial compartments. Accordingly, if 1 L of D5W is infused, approximately 664 mL will move into the ICF and 336 mL will remain in the ECF compartment. Of these 336 mL, only 84 mL (25 %) will remain in the intravascular compartment (Fig. 1.2). Fig. 1.1 Distribution of total Total body water (60%) body water (TBW) in a 70 kg 70 kg man. ECF extracellular fluid volume, ICF intracellular fluid TBW= 42 L volume 1/3 ECF 2/3 ICF ICF= 28 L ECF= 14 L Intravascular= 3.5 L Interstitium= 11.5 L Intravacular Interstitial (25%) (75%) Fig. 1.2 Distribution of 5 % D5W (1L or 1,000 mL) dextrose in water (D5W) in the body. ECF extracellular fluid volume, ICF intracellular fluid volume ECF= 333 mL ICF= 667 mL Intravascular= 83 mL Interstitium= 250 mL The retention of hypotonic solutions such as 0.45 % NaCl (half-normal) is different. 0.45 % NaCl is considered to be a 50:50 mixture of normal saline and free water. If 1 L of 0.45 % NaCl is infused, the free water (500 mL) is distributed between ICF (333 mL) and ECF (167 mL) compartments. Of 167 mL, only 42 mL (25 %) will remain in the intravascular compartment. Considering the other 500 mL, which behaves like 0.9 % saline, 375 mL (75 %) will move into the interstitial space, and 125 mL stays in the intravascular compartment (Fig. 1.3). Thus, the total volume remaining intravascularly after 1 L of infusion would be only 167 mL (42 + 125 ¼ 167 mL). On the other hand, more fluid is retained in the intravascular space with isotonic fluids. If 1 L of normal saline is infused, all of the fluid will remain in the intravascular compartment, and then approximately