COVID-19 Croup May Be More Severe Than Typical Croup

By Megan Brooks

September 25, 2020

NEW YORK (Reuters Health) - Clinicians from Virginia report what they believe are the first documented cases of croup as a manifestation of SARS-CoV-2 infection.

The limited experience with this newly described "COVID-19 croup" suggests that patients "might not improve as rapidly with treatments as typical croup patients," Dr. Paul Mullan and colleagues of Children's Hospital of the King's Daughters (CHKD) in Norfolk write in The American Journal of Emergency Medicine.

All three previously healthy children (ages 11 months, 2 years, and 9 years) were admitted from the emergency department to CHKD last spring and summer (croup typically strikes in the fall and winter).

They presented with non-specific upper respiratory tract symptoms that developed into a barky cough with associated stridor at rest and respiratory distress.

"All three children were tested with a viral panel that screened for 21 of the most common respiratory pathogens that we see clinically in practice. All three were positive only for SARS-CoV-2 and negative for all other pathogens, strongly suggesting that SARS-CoV-2 was responsible for their croup," Dr. Mullan told Reuters Health by email.

"Given that other coronaviruses have been described in prior years as a cause of croup, we strongly believe that these children had croup because of their SARS-CoV-2 infections," he said.

All three children received multiple doses of nebulized racemic epinephrine with "minimal to no improvement" shortly afterward. They also received multiple doses of dexamethasone, something that happens "infrequently" at CHKD and is reserved for atypical cases not responding as expected to initial treatments, the team notes in their article.

They further note that symptom scores with dexamethasone typically improve in 0.5 to 4 hours. But in these three children, the time from initial dexamethasone to the resolution of stridor at rest ranged from 13 to 21 hours. "This is significantly longer than our normal expectations for moderate to severe croup," they say.

One child required heliox therapy and admission to the intensive-care unit. All three children were eventually discharged.

The clinicians note that inpatient interventions for croup are "relatively infrequent (22.6% in one study), suggesting potentially more severe pathophysiology with COVID-19 croup versus previously described croup."

They also point out that pathogen testing is typically not indicated in croup, but with COVID-19 croup, SARS-CoV-2 testing "should be considered given the prognostic significance and prolonged quarantine implications." At CHKD, all croup patients are now tested for SARS-CoV-2.

Dr. Mullan told Reuters Health, "Clinicians and caregivers should follow local guidance, such as the CDC guidelines, when determining whether to test children for SARS-CoV-2. In prior years, most emergency providers would not have tested for the specific virus responsible for a case of croup, because it was usually secondary to parainfluenza and knowledge of the specific virus would not have changed management."

"Testing for SARS-CoV-2 in pediatric croup assumes novel importance during this pandemic for home isolation implications, quarantining and testing of close contacts, and prognostic implications for both the croup course of illness as well as the potential for future MIS-C presentation in the child," Dr. Mullan added.

The team says further study is needed to determine the natural history and optimal management of COVID-19 croup.

SOURCE: The American Journal of Emergency Medicine, online September 15, 2020.