Multicentre observational study on multisystem inflammatory syndrome related to COVID-19 in Argentina.

BACKGROUND
The impact of the Pediatric Inflammatory Multisystem Syndrome temporally-associated with SARS-CoV-2 (PIMS-TS) in low and middle-income countries remains poorly understood. Our aim was to understand the characteristics and outcomes of PIMS-TS in Argentina.


METHODS
This observational, prospective and retrospective multicenter study, enrolled patients younger than 18 years-old showing PIMS-TS, Kawasaki disease (KD) or Kawasaki shock syndrome (KSS) manifestations between March 2020 and May 2021. Patients were followed-up until hospital discharge or death (which occurred in one case). The primary outcome was PICU admission. Multiple logistic regression was used to identify variables predicting PICU admission.


RESULTS
Eighty-one percent, 82% and 14% of the 176 enrolled patients fulfilled the suspect case criteria for PIMS-TS, KD, and KSS, respectively. Temporal association with SARS-CoV-2 was confirmed in 85% of the patients and 38% were admitted to PICU. The more common clinical manifestations were fever, abdominal pain, rash and conjunctival injection. Lymphopenia was more common among PICU-admitted patients (87% versus 51%, p<0.0001), who also showed a lower platelet count and higher plasmatic levels of inflammatory and cardiac markers. Mitral valve insufficiency, left ventricular wall motion alterations, pericardial effusion and coronary arteries alterations were observed in 30%, 30%, 19.8%, 18.6% of the patients, respectively. Days to initiation of treatment, rash, lymphopenia, and low platelet count did significant independent contributions to PICU admission.


CONCLUSION
Rates of severe outcomes of PIMS-TS in the present study agreed with those observed in high-income countries. Together with other published studies, this work helps to better understand this novel clinical entity.