USMLE® STEP 2 CK: PEDIATRICS Lecture Notes 2019 Table of Contents USMLE Step 2 CK Lecture Notes 2019: Pediatrics Cover Title Page Copyright Editors Feedback Page Chapter 1: The Newborn Apgar Score Birth Injuries Physical Examination: Normal Findings Newborn Screening Fetal Growth and Maturity Specific Disorders Infections Substance Abuse and Neonatal Withdrawal Chapter 2: Genetics/Dysmorphology Abnormalities of Chromosomes Early Overgrowth with Associated Defects Unusual Brain and/or Neuromuscular Findings with Associated Defects Facial Features as the Major Defect Osteochondrodysplasias Connective Tissue Disorders Environmental Agents Miscellaneous Sequences Miscellaneous Associations Chapter 3: Growth and Nutrition Childhood Growth Disorders of Growth Feeding Breast Feeding Solids Chapter 4: Development Overview Primitive Reflexes and Developmental Milestones Chapter 5: Behavioral/Psychological Disorders Eating Disorders Elimination Disorders Sleep Disorders Chapter 6: Immunizations Active Immunizations Active Immunization after Disease Exposure Specific Vaccines (Routine Vaccinations) Chapter 7: Child Abuse and Neglect Introduction Physical Abuse Sexual Abuse Chapter 8: Respiratory Disease Acute Inflammatory Upper Airway Obstruction Congenital Anomalies of the Larynx Airway Foreign Body Inflammatory Disorders of the Small Airways Pneumonia Cystic Fibrosis (CF) Sudden Infant Death Syndrome (SIDS) Chapter 9: Allergy and Asthma Allergies Asthma Chapter 10: Immune-Mediated Disease Evaluation of Suspected Immune Deficiency Specific Defects Other Immune Deficiencies Chapter 11: Disorders of the Eye Abnormalities of the Eye Structures Eye Injuries Periorbital versus Orbital Cellulitis Chapter 12: Disorders of the Ear, Nose, and Throat Ears Nose and Throat Chapter 13: Cardiology Cardiac Evaluation and Congenital Heart Lesions Pediatric Heart Sounds and Innocent Murmurs Left to Right Shunts Stenotic Lesions Right to Left Shunts (Cyanotic Lesions) Mixed Lesions Regurgitant Lesions Other Cardiac Pathology Hypertension Chapter 14: Gastrointestinal Disease Oral Cavity Gastroenteritis Vomiting Hematochezia Constipation Chapter 15: Renal and Urologic Disorders Urinary Tract Infection (UTI) Vesicoureteral Reflux (VUR) Obstructive Uropathy Diseases Presenting Primarily with Hematuria Polycystic Kidney Disease Diseases Presenting with Proteinuria Male Genitourinary Disorders Chapter 16: Endocrine Disorders Pituitary Disorders Thyroid Disorders Parathyroid Disorders Adrenal Disorders Diabetes Mellitus Chapter 17: Orthopedic Disorders Disorders of the Hip Intoeing Disorders of the Knee Disorders of the Spine Disorders of the Upper Limb Osteomyelitis and Septic Arthritis Osteogenesis Imperfecta Bone Tumors Chapter 18: Rheumatic and Vasculitic Disorders Juvenile Idiopathic Arthritis (JIA) Systemic Lupus Erythematosus (SLE) Neonatal Lupus Kawasaki Disease Henoch-Schönlein Purpura (HSP) Chapter 19: Hematology Anemias of Inadequate Production Congenital Anemias Acquired Anemias Megaloblastic Anemias Hemolytic Anemias Hemoglobin Disorders Thalassemias Hemorrhagic Disorders Platelet Disorders Chapter 20: Oncology Leukemia and Lymphoma Brain Tumors Other Malignancies Chapter 21: Neurology Central Nervous System (CNS) Anomalies Seizures Neurocutaneous Syndromes Encephalopathies Neurodegenerative Disorders Neuromuscular Disease Chapter 22: Infectious Disease Meningitis Pertussis Mycobacteria Lyme Disease Rocky Mountain Spotted Fever Mycotic Infections Viral Infections Other Viral Diseases Helminthic Diseases Chapter 23: Adolescence Mortality/Morbidity, Sexuality, and STIs Acne USMLE® is a joint program of the Federation of State Medical Boards (FSMB) and the National Board of Medical Examiners (NBME), neither of which sponsors or endorses this product This publication is designed to provide accurate information in regard to the subject matter covered as of its publication date, with the understanding that knowledge and best practice constantly evolve The publisher is not engaged in rendering medical, legal, accounting, or other professional service If medical or legal advice or other expert assistance is required, the services of a competent professional should be sought This publication is not intended for use in clinical practice or the delivery of medical care To the fullest extent of the law, neither the Publisher nor the Editors assume any liability for any injury and/or damage to persons or property arising out of or related to any use of the material contained in this book © 2018 by Kaplan, Inc Published by Kaplan Medical, a division of Kaplan, Inc 750 Third Avenue New York, NY 10017 All rights reserved under International and Pan-American Copyright Conventions By payment of the required fees, you have been granted the non-exclusive, non-transferable right to access and read the text of this eBook on screen No part of this text may be reproduced, transmitted, downloaded, decompiled, reverse engineered, or stored in or introduced into any information storage and retrieval system, in any form or by any means, whether electronic or mechanical, now known or hereinafter invented, without the express written permission of the publisher ISBN-13: 978-1-5062-3629-2 EDITORS William G Cvetnic, MD, MBA Fellow of the American Academy of Pediatrics Board Certified in Pediatrics and Neonatal-Perinatal Medicine Jacksonville, Florida Eduardo Pino, MD Associate Professor, Department of Pediatrics Marshall University School of Medicine Medical Director, Hoops Family Children's Hospital Cabell Huntington Hospital Huntington, West Virginia ENTEROBIASIS A mother brings her 4-year-old child to the physician with a history of always scratching her anus The mother is embarrassed by this behavior The child attends daycare and loves to play in the sandbox NOTE Most parasites, ova, and cysts can be identified on fecal smear Etiology—Enterobius vermicularis is the parasite implicated in pinworm infection Small, white, threadlike nematodes Most common helminth in the United States Primarily in institutional/family settings that include children; highest at age 5–14 Eggs are ingested from being carried on fingernails, clothing, bedding, or house dust; after ingestion, adult worms within 1–2 months Inhabits cecum, appendix, ileus, and ascending colon; female migration at night to deposit eggs on perianal region and perineum Clinical Presentation—most common symptoms include itching and restless sleep and no eosinophilia Diagnosis—history and use of adhesive cellophane tape (tape test) at night when child is asleep Treatment—infected person and entire family receive single oral dose of mebendazole and repeat in 2 weeks 23 ADOLESCENCE LEARNING OBJECTIVES Describe the epidemiology including morbidity and mortality of diseases of adolescence Answer questions related to adolescent sexuality and sexually transmitted diseases Describe the causes and treatments of acne MORTALITY/MORBIDITY, SEXUALITY, AND STDS A 14-year-old girl who has not yet achieved menarche presents to the physician with her concerned mother The mother is afraid that her daughter is not “normal.” On physical examination, the patient appears well nourished and is in the 50th percentile for height and weight Her breast examination shows the areolar diameter to be enlarged, but there is no separation of contours Her pubic hair is increased in amount and is curled but is not coarse in texture The mother and her daughter wait anxiously for your opinion INTRODUCTION TO ADOLESCENCE AND PUBERTY Definition—period bridging childhood and adulthood Begins at age 11–12 years, ends at 18–21; includes puberty Physical and psychological/behavioral changes Completes pubertal and somatic growth Develops socially, cognitively and emotionally Moves from concrete to abstract thinking Establishes independent identity Prepares for career All adolescents are at increased risk of mortality and morbidity Mortality Accidents—especially MVAs Suicide—boys are more successful Homicide—more likely in blacks Cancer—Hodgkin lymphoma, bone, CNS Morbidity Unintended pregnancy STIs Smoking Depression Crime There are 3 stages of adolescence Early (Age 10-14 years) Physical changes (puberty) including rapid growth, puberty including development of secondary sexual characteristics Compare themselves to peers (develop body image and self-esteem) Concrete thinkers and feel awkward Middle (Age 15-16 years) More independent and have a sense of identity Mood swings are common Abstract thinking Relationships are one-sided and narcissistic Late (Age >17 years) Less self-centered Relationships with individuals rather than groups Contemplate future goals, plans, and careers Idealistic; have a sense of right and wrong Female Both Male Stage Breast Pubic hair Genitalia I Preadolescent None Childhood size II Breast bud Sparse, long, straight Enlargement of scrotum/testes III Areolar diameter enlarges Darker, curling, increased Penis grows in length; testes continue to enlarge amount IV Secondary mound; separation of Coarse, curly, adult type contours V Penis grows in length/ breadth; scrotum darkens, testes enlarge Mature female Adult, extends to thighs Adult shape/size Table 23-1 Tanner Stages of Development Puberty Variability in onset, duration No variability in order of changes Irreversible Physical reflects hormonal Variants of development are normal and most cases only require reassurance from the physician to the patient and their family Breast asymmetry and gynecomastia often seen in males at Tanner stage 3 Irregular menses due to anovulatory cycles seen in females starting to menstruate SEXUALLY TRANSMITTED INFECTIONS Gonorrhea A 16-year-old girl presents to her physician because of fever, chills, pain, and swelling in the small joints of her hands, and a maculopapular rash on her upper and lower extremities NOTE Untreated GC/Chlamydia may result in PID and/or infertility (due to tubal scarring) Neisseria gonorrhoeae usually infects mucosal membranes of the genitourinary tract and less commonly the oropharynx, rectum, and conjunctiva Clinical presentation includes urethritis, cervicitis, and dysuria Asymptomatic patients are at higher risk for dissemination, including fever, chills, and arthritis Physical examination Males present with dysuria and purulent penile discharge Females present with purulent vaginal discharge, cervicitis, abdominal pain, and/or dysuria Rectal gonorrhea may present with proctitis, rectal bleeding, anal discharge, and/or constipation Tests Culture from discharge Blood cultures if dissemination is suspected Gram stain may show intracellular diplococci Check for other STIs, including syphilis and HIV infection Treat with single-dose ceftriaxone or single-dose azithromycin; treat partners Alternatives include doxycycline for 7 days (not in children 4.5 >5