Faculty Bibliography

OBJECTIVE:Croup due to infection with the omicron variant of COVID is an emerging clinical entity, but distinguishing features of omicron croup have not yet been characterized. We designed a study to compare the clinical features of croup patients presenting to the pediatric emergency department pre-COVID pandemic with COVID-positive croup patients who presented during the initial omicron surge. METHODS:This was a retrospective observational cohort study of children 0 to 18 years old who presented to our urban, tertiary care pediatric emergency department with symptoms of croup. The study compared a cohort of croup patients who presented in the year before the onset of the COVID pandemic to a cohort of COVID-positive croup patients who presented during the initial omicron surge. The primary outcomes included illness severity and treatments required in the emergency department. The secondary outcome was hospital admission rate. RESULTS:There were 499 patients enrolled in the study, 88 in the omicron croup cohort and 411 in the classic croup cohort. Compared with the classic croup patients, omicron croup patients were more likely to present with stridor at rest (45.4% vs 31.4%; odds ratio [OR], 1.82; confidence interval [CI], 1.14-2.91) and hypoxia (3.4% vs 0.5%; OR, 7.22; CI, 1.19-43.86). Omicron croup patients required repeat dosing of inhaled epinephrine in the emergency department more often (20.4% vs 6.8%; OR, 3.51; CI, 1.85-6.70), and they were more likely to require respiratory support (9.1% vs 1.0%; OR, 10.18; CI, 2.99-34.60). Admission rates were significantly higher for omicron croup patients than for classic croup patients (22.7% vs 3.9%; OR, 7.26; CI, 3.58-14.71), and omicron croup patients required intensive care more frequently (5.7% vs 1.5%; OR, 4.07; CI, 1.21-13.64). CONCLUSIONS:Pediatric patients with omicron croup develop more severe disease than do children with classic croup. They are more likely to require additional emergency department treatments and hospital admission than patients with croup before the COVID pandemic.

OBJECTIVES/OBJECTIVE:Patients with multisystem inflammatory disease in children (MIS-C) are at risk of developing shock. Our objectives were to determine independent predictors associated with development of delayed shock (≥3 hours from emergency department [ED] arrival) in patients with MIS-C and to derive a model predicting those at low risk for delayed shock. METHODS:We conducted a retrospective cross-sectional study of 22 pediatric EDs in the New York City tri-state area. We included patients meeting World Health Organization criteria for MIS-C and presented April 1 to June 30, 2020. Our main outcomes were to determine the association between clinical and laboratory factors to the development of delayed shock and to derive a laboratory-based prediction model based on identified independent predictors. RESULTS:Of 248 children with MIS-C, 87 (35%) had shock and 58 (66%) had delayed shock. A C-reactive protein (CRP) level greater than 20 mg/dL (adjusted odds ratio [aOR], 5.3; 95% confidence interval [CI], 2.4-12.1), lymphocyte percent less than 11% (aOR, 3.8; 95% CI, 1.7-8.6), and platelet count less than 220,000/uL (aOR, 4.2; 95% CI, 1.8-9.8) were independently associated with delayed shock. A prediction model including a CRP level less than 6 mg/dL, lymphocyte percent more than 20%, and platelet count more than 260,000/uL, categorized patients with MIS-C at low risk of developing delayed shock (sensitivity 93% [95% CI, 66-100], specificity 38% [95% CI, 22-55]). CONCLUSIONS:Serum CRP, lymphocyte percent, and platelet count differentiated children at higher and lower risk for developing delayed shock. Use of these data can stratify the risk of progression to shock in patients with MIS-C, providing situational awareness and helping guide their level of care.

Multisystem inflammatory syndrome in children (MIS-C) is an uncommon but emerging syndrome related to SARS-CoV-2 infection. While the presentation of MIS-C is generally delayed after exposure to the virus that causes coronavirus 2019, both MIS-C and Kawasaki disease (KD) share similar clinical features. Multisystem inflammatory syndrome in children poses a diagnostic and therapeutic challenge given the lack of definitive diagnostic tests and a paucity of evidence regarding treatment modalities. We review the clinical presentation, diagnostic evaluations, and management of MIS-C and compare its clinical features to those of KD.