LAUSR

Abstract 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.