Skip to main content

Welcome to the July 16th edition of The Differential, our weekly pediatrics briefing. Created by physicians for physicians, The Differential is designed to be quick (skim it in just a few minutes) and thorough (all the information you need is in right here). Today’s Differential is edited by Dr. Cherilyn Cecchini, a pediatrician who recently completed residency training at Children’s National Medical Center.

The Differential for Pediatrics is available as a free weekly email.
Subscribe to The Differential.

Single-Sentence Summaries

1. 10% of U.S. middle and high school students report smoking from a hookah, and in a single hookah session a smoker can inhale 200 cigarettes worth of smoke. AAP News July 2018

2. An analysis of the 50,000 reports the U.S. Vaccine Adverse Event Reporting System (VAERS) received about diphtheria-tetanus-acellular pertussis (DTaP) vaccines between 1991-2017 revealed no new or unexpected adverse events — but highlighted the need to reduce provider error. Pediatrics July 2018

3. Tinea capitis, a fungal infection of the scalp commonly known as ringworm, is emerging in Europe and the treatment regimen is not well defined. New England Journal of Medicine May 2018

4.  More than two-thirds of children 4 to 7 years old who were killed in U.S. car crashes from 2011 to 2015 were not in an age-appropriate child restraint system. Clinical Pediatrics July 2018

5. Chronic urticaria appears to last longer in adults than in children. Pediatric Allergy and Immunology July 2018

Clinical Quiz

A six-year-old female with a two-week history of daily fevers presents with a linear macular rash. Her mother says the rash appears in areas where her daughter has scratched herself. It is most noticeable when she is febrile. Examination reveals swollen knee joints and lymphadenopathy. What condition is revealed by this presentation?

A. Rheumatic fever
B. Henoch-Schönlein purpura
C. Systemic juvenile idiopathic arthritis
D. Dermographism

Answer at the bottom of this email, or click here to see the full case and discussion on Figure 1.

Editor’s Pearl

The AAP released comprehensive guidance on car-seat safety in a 2011 policy statement. Infants and toddlers should remain in the rear seat in a rear-facing car safety seat until they are 2 years of age or until they reach the highest weight or height allowed by the manufacturer of their car safety seat. Test preparers love to ask about this, so be sure to review additional information here.


A. Systemic juvenile idiopathic arthritis

This patient’s lesions—developed at the site of cutaneous injury (in this case scratching)—are known as the Koebner phenomenon. This unique rash and the patient’s quotidian fever and inflamed joints are characteristic of juvenile idiopathic arthritis. The diagnosis can be made clinically, but laboratory findings may be used to rule out other conditions. Treatments may include a combination of nonsteroidal anti-inflammatory drugs, glucocorticoids, biologic agents, or physical therapy.

This briefing is made by physicians, for physicians. If you find it useful, please subscribe below.

To connect with healthcare professionals around the world who are viewing, discussing, and sharing medical cases, join Figure 1.