Importance β-Lactam antibiotics are among the safest and most effective antibiotics. Many
patients report allergies to these drugs that limit their use, resulting in the use of broad-…

Delayed Local Reactions to mRNA-1273 Vaccine Delayed cutaneous reactions developed
in 12 patients days after initial injection-related symptoms resolved. The reactions, some as …

Methods We prospectively studied Mass General Brigham (MGB) employees who received
their first dose of an mRNA COVID-19 vaccine (12/16/2020-2/12/2021, with follow-up through …

The increasing availability of electronic health data presents a major opportunity in
healthcare for both discovery and practical applications to improve healthcare. However, for …

… Erica S Shenoy Erica S Shenoy … using Wilcoxon rank sum test for continuous variables and
χ 2 test or Fisher’s exact test, as appropriate, for binary variables. To determine the adjusted …

… Editor’s Note: This article was published on April 1, 2020, at NEJM.org. In a letter to the
editor on June 3, 2020, the authors of this article state “We strongly support the calls of public …

Background Self-reported penicillin allergy infrequently reflects an inability to tolerate
penicillins. Inpatients reporting penicillin allergy receive alternative antibiotics that might be …

A Man with Perianal and Penile Ulcers, Pain, and Rash A 31-year-old man was admitted
with perianal and penile ulcers, rectal pain, and vesiculopustular rash. He had first noticed …

Methods| We prospectively studied Mass General Brigham employees who received an
mRNA COVID-19 vaccine (first dose: December 16, 2020, to January 20, 2021; follow-up …

Background Reported penicillin allergy rarely reflects penicillin intolerance. Failure to
address inpatient penicillin allergies results in more broad-spectrum antibiotic use, treatment …