AUTHOR=Orsi Silvia Maria , Pepino Carlotta , Rossoni Lisa , Serafino Margherita , Caorsi Roberta , Volpi Stefano , Palmeri Serena , Faragli Alessandro , Lugani Francesca , Bigatti Carolina , Ghiggeri Gian Marco , Verrina Enrico Eugenio , La Porta Edoardo , Angeletti Andrea 

TITLE=Case Report: Multisystem inflammatory syndrome in children with associated proximal tubular injury

JOURNAL=Frontiers in Nephrology

VOLUME=Volume 3 - 2023

YEAR=2023

URL=https://www.frontiersin.org/journals/nephrology/articles/10.3389/fneph.2023.1194989

DOI=10.3389/fneph.2023.1194989

ISSN=2813-0626

ABSTRACT=Introduction 
Sars-CoV2 infection in the pediatric population could be associated with a multiorgan inflammatory syndrome called children's multisystem inflammatory syndrome (MIS-C). Even kidneys can be affected with a broad spectrum of possible injuries, whose pathogenetic mechanisms are still unclear.
Case report 
We report a peculiar case of a 5-year-old boy with a severe cardiac involvement in the contest of MIS-C. After two weeks, an abdominal ultrasound showed a massive bladder "debris", followed by the onset of a normoglycemic glycosuria. Over time, there was a progressive increase in glycosuria and the presence of a mat of amorphous phosphate crystals was evidenced on urinary sediment. Together with the findings of hypo-uricemia, increased urinary uric acid and globally increased urinary amino acids, a clinical picture of kidney proximal tubular damage with secondary Fanconi-like syndrome took shape. 
Discussion
 We described the case of a patient with MIS-C with cardiac and kidney involvement characterized by proximal tubular damage which slowly improved but still persists at 8 months follow-up. The pathogenesis of the damage is unclear and probably multifactorial.