A new study has found the molecular signature of Long COVID in children’s plasma and used an AI tool test capable of making the diagnosis based on the results of the blood sample, with 93% accuracy.
“The immunological data produced in this study provide the evidence needed to identify therapeutic targets to be tested in efficacy and safety studies in pediatric Long COVID,” said, co-author Nicola Cotugno at the Complex Operative Unit of Clinical Immunology and Vaccinology of the Bambino Gesù IRCCS Pediatric Hospital.
The work was done by the Università Cattolica del Sacro Cuore, Rome campus – Fondazione Policlinico Universitario Agostino Gemelli IRCCS and the Ospedale Pediatrico Bambino Gesù IRCCS.
The study was published in the journal Pediatric Research and was led by Danilo Buonsenso, PhD, specialist in pediatrics at the Faculty of Medicine and Surgery of the Catholic University.
Long COVID affects on average 0.5% of pediatric patients exposed to SARS-CoV-2. This condition, also known as Post COVID or Post-Acute Sequelae of SARS-CoV-2, is characterized by the persistence of signs and symptoms for at least 8–12 weeks, symptoms not present before the viral infection, with a negative impact on daily life. Long COVID affects patients of almost all age groups, and among pediatric patients those older than 10 years seem to be most affected, regardless of the severity of the initial infection.
In adults, the Long COVID “sign” has been found in blood, but a similar marker hadn’t yet been found in children.
This team analyzed the blood of 112 young people aged 0–19 years, of whom 34 had a clinical diagnosis of Long COVID, 32 had the active infection at the time of the study, 27 had Multisystem Inflammatory Syndrome (MIS-C, a severe hyper-inflammatory reaction that almost always requires intensive care), and 19 were healthy control peers.
The researchers analyzed the blood protein component (proteomics) and saw that, compared to the control groups, the pediatric Long COVID group was characterized by a higher presence in plasma of the pro-inflammatory and pro-angiogenic chemokine sets CXCL11, CXCL1, CXCL5, CXCL6, CXCL8, TNFSF11, OSM, STAMBP1a. An artificial intelligence model based on proteomic profiling was able to identify long COVID with an accuracy of 0.93, a specificity of 0.86 and a sensitivity of 0.97.
They conclude that Long COVID in children presents a distinct protein signature in plasma, characterized by increased inflammation in general and at the level of blood vessel walls (endothelia), as already seen in adults. The discovery could lead to the development of a simple routine diagnostic test based on a blood sample, allowing timely and complete care of the pediatric patient with Long COVID.
“This work demonstrates incontrovertibly that Long COVID, also in pediatric age, is an organic immune-mediated disease, for which new funding is needed to study the best therapeutic approaches,” Buonsenso concluded.
