Children’s National Hospital is treating 23 children for an inflammatory syndrome associated with covid-19, a hospital spokesperson said Wednesday night.

The illness, known as multisystem inflammatory syndrome in children, is a recently discovered complication from the novel coronavirus.

At least three cases of the syndrome have been reported in the District, officials said. One case has been reported to state officials in Virginia as of Wednesday night, and three cases have been reported to Maryland’s state health department, officials said.

The discrepancy in the numbers reported by the hospital and individual jurisdictions was not immediately clear.

NBC Washington first reported the pediatric cases at Children’s National Hospital, and hospital spokeswoman Beth Riggs confirmed that the hospital was treating 23 young patients.

Symptoms for the syndrome, which can cause problems with a child’s heart and other organs, may include persistent fever and low blood pressure.

City officials told the D.C. Council on Wednesday that at least three children in the nation’s capital have developed the syndrome. LaQuandra Nesbitt, director of the D.C. Department of Health, told city lawmakers that medical professionals know very little about the syndrome and the virus’s effect on children.

Although the virus disproportionately kills the elderly, the inflammatory syndrome has been linked to the death of a 15-year-old in Baltimore County.

The death is one of three cases of the syndrome reported to Maryland’s health department, said Michael Ricci, a spokesman for Gov. Larry Hogan (R).

Only one case of the syndrome had been reported to Virginia’s health department as of Wednesday night. That case involved a child in the Fairfax health district who was hospitalized on May 5 and has since been discharged and is recovering at home. The number could change over the next few days given reporting lags, said Alena Yarmosky, spokeswoman for Virginia Gov. Ralph Northam (D).

Laura Vozzella and Ovetta Wiggins contributed to this report.