Thomas Hajzus has had his ups and downs with the Peters Township School District, but it was nothing compared to the dangerous fluctuations in blood sugar levels he began experiencing last month.

The Peters Township High School principal since 1990, Dr. Hajzus, 54, is now battling diabetes and is on paid medical leave.

Unaware that he had the disorder, Dr. Hajzus collapsed on his kitchen floor on Jan. 30 and suffered temporary blindness and blood glucose levels that were off the chart before doctors diagnosed him with type 2 diabetes.

Since then, Dr. Hajzus has been granted a paid medical leave of absence retroactive from March 1 to June 30 by the school board -- members of which are some of the same people with whom he was locked in a prolonged legal battle for several years.

Dr. Hajzus successfully sued the district in October 2007, claiming he was illegally demoted because he suffered from depression and anxiety.

Two years ago, the parties reached a settlement, calling for Dr. Hajzus to retain his job as principal until 2013 along with a financial package of $500,000-plus. His salary is about $109,900 a year.

Acting assistant principal Frank Brettschneider was appointed March 8 to temporarily take over Dr. Hajzus' duties at a rate of $300 a day. Dr. Hajzus, who was hospitalized after his collapse in January, said he hoped to return to work, but that would be up to his doctors.

Dr. Hajzus said his doctors told him that his extreme blood glucose levels were brought on, partly, by prolonged and "inappropriate" stress levels.

He said when he first tested his blood glucose levels -- he believes they were more than 1,000 mg/dL -- the digital meter could not measure them.

The designation mg/dL (milligrams/deciliter) is the traditional unit for measuring blood glucose.

"That is very high and life threatening," said Dr. Linda Siminerio, director of the University of Pittsburgh Diabetes Institute. A normal reading is a daily average of 118 mg/dL.

Extremely high levels are associated with coma or death, and Mr. Hajzus said he was on display for endocrinologists and other curious doctors during the three days he spent in intensive care at St. Clair Hospital.

They were amazed that he was still walking, he said.

"Some of the doctors were just inquisitive," he recalled. "They couldn't understand how I didn't have a stroke or organ damage."

Gradually, a new diet and exercise plan, along with 30 units of insulin twice a day, brought Dr. Hajzus' blood glucose levels down to normal.

If his levels spike to 300 mg/dL or higher again, doctors have told him his vision could become severely impaired.

But, he also experienced the other end of the yo-yo several days after his diagnosis when he failed to check his blood sugar levels or eat before a parent-teacher conference.

He attended the conference, but then Dr. Hajzus found himself at the low end of the blood glucose spectrum, below 70 mg/dL, which can cause coma as well.

Since then, Dr. Hajzus said he has committed to better managing his diabetes, by working out several times a day on a treadmill and elliptical machine, and by isolating himself from stress-inducing environments, such as work.

He's hoping that his mistakes will teach others to take care of their bodies.

Dr. Siminerio said researchers were still investigating the role stress may play in diabetes and on blood glucose levels. They also are looking into other potential causes, such as a virus.

"Some people think stress could be the influence that sets it off," she said. "It's still under observation."

She said blood glucose levels of 950 mg/dL would normally be accompanied by other symptoms, such as unexplained weight loss; extreme lethargy; dry, itchy skin; extreme thirst; and frequent urination.

Dr. Hajzus said he lost 27 pounds and was drinking more water, but he attributed it to a new diet he and his wife have started.

Dr. Hajzus' vision problems may have been caused by nerve damage or from a buildup of glucose in the fluid behind the lens of the eye, Dr. Siminerio said.

Dr. Hajzus said he now realizes how important it is to maintain regular doctor appointments and schedule annual eye exams.

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