EVERGREEN PARK, Ill. (CBS) — Concerned parents on the Southwest Side and surrounding suburbs were asking plenty of questions Wednesday, following new information about a doctor’s suicide.

The note he left indicated he might not have given some of his young patients vaccinations.

CBS 2’s Jim Williams has the story from Evergreen Park.

Parents have been calling the sheriff’s office and writing lots of social media posts, some calling Dr. Van Koinis a great pediatrician. But others are expressing fear.

So what can parents do now? CBS 2 got an answer.

Doctor Van Koinis left behind a suicide note that the Cook County Sheriff said indicated that Koinis regretted how he handled vaccinations.

Sheriff Tom Dart told CBS 2 the note mentioned a 10 year period in which the pediatrician either doctored records or gave fake vaccinations.

The fear is that some of the young patients he saw at his office on West 95th in Evergreen Park might not have received the shots.

Mary Mullaney said officials in Worth Township told her her preteen son, a Koinis patient, was missing vaccinations.

“They said he was extremely behind on his shots and I just went with what Dr. Koinis said that they needed,” said Mullaney. “Because I thought, you know, he’s their pediatrician. He knows what shots are needed.”

One doctor’s office in the southwest suburbs told CBS 2 it’s been taking calls from concerned parents of Koinis’ former patients.

Dr. Priya Malhotra of the Weissbluth Pediatrics Practice in Chicago said parents can get answers by scheduling what’s called a titers test.

“These titers can test for each of the immunizations, specifically the bacteria and viruses that the immunizations cover for and these titers will you let is your child is immunized against the infection or not,” said Malhotra.

Doctors are able to get results of those tests in only a few days.

To be clear, some parents told CBS 2 they are convinced Doctor Koinis gave their children the vaccinations.