Background: covid19 infection, in children compared to adults, often occurs in a pauci and/or asymptomatic manner, but in some cases, a multisystem inflammatory syndrome (MIS) may occur in the 4-6 weeks following the infection. There are few data on the features of MIS after the clinical recovery phase, therefore we have described three cases of children with post-covid19 infection syndrome.
Case presentation: out of the three cases described, in two children the onset clinical symptoms were similar to Kawasaki syndrome, while in the other neurological impairment was prevalent. In none of the three there were gastrointestinal symptoms, while the signs of interstitial disease were constant on lung ultrasound. In all of them, there was an increase in the inflammatory markers, high levels of ferritin, lymphocytopenia and thrombocytopenia only in one case. The lipid profile at onset was characterized by an increase in triglyceride levels. In all cases the course was benign with resolution of the symptoms upon admission within 4-5 days. After 1 month from the clinical recovery phase, the patients showed normalization of cytokines, inflammatory markers and triglyceride levels, while the total cholesterol value increased. Covid19 infection leads to an acute phase response with increase of the triglyceride in addition to inflammatory markers and the signs of interstitial disease on lung ultrasound.
Conclusions: the inflammatory markers and lung involvement normalize over 30 days, while an initial increase of the triglyceride - and later in total cholesterol - suggest a direct relationship between triglyceride and inflammatory markers at the beginning, and between total cholesterol and host immune response during the follow-up.