Major League Baseball has completed its review of Nationals Dominican Republic prospect Yewri Guillen’s death and determined the 18-year-old shortstop died not of bacterial meningitis, as originally diagnosed, but of a brain infection caused by an aggressive sinus infection.

The review, led by Dr. Gary Green, also concluded that the Nationals “took the proper steps to insure that Guillen’s medical care was handled appropriately, and that proper protocols were followed to prevent the spread of meningitis when that infection was suspected as the cause of Guillen’s illness.”

(UPDATED, 2:23: The original diagnosis of bacterial meningitis came from the doctors in the Dominican Republic who treated Guillen before he died suddenly, a source with knowledge of MLB’s investigation said. The Nationals, who paid for Guillen’s medical bills after he went to a Santo Domingo hospital, received the information from the doctors and had nothing to do with the initial diagnosis. MLB learned the cause of death only after Dominican officials provided the league with autopsy results.)

While the cause of death was not bacterial meningitis, the initial diagnosis prompted changes by baseball’s Medical Advisory Committee in how players and staff are vaccinated. Every player living at a Dominican training facility will be offered a vaccination, a common procedure at colleges and universities to prevent infectious diseases, and every player and staff member has received a shot since Guillen’s death, which occurred early on the morning of April 15.

When and if more information becomes available, I will post it here.