UB research scientist Dr. Alan Lesse recently received a $690,500 grant to study Staphylococcus Aureus, a potentially fatal bacterial infection that can cause a wide range of symptoms.
The study led by Lesse, an associate professor in pharmacology and toxicology, will focus on identifying different variations of the staphylococcus aureus bacterium (SAB).
Students should be aware that a large percentage of humans currently carry the staphylococcus aureus bacteria, Lesse said. It can enter the body through small cuts in the skin or mouth and cause infection.
"It's very common to be colonized with the organism," Lesse said. "You could probably culture it from...20 to 30 percent of individuals."
SAB is somewhat different from other bacteria in several ways. For one, the mortality rate is unusually high. According to Lesse, once the bacterium enters the bloodstream, the mortality rate is around 25 percent. If the bacterium reaches the heart valves, the rate can increase to between 30 and 40 percent.
"It will actually stick on the heart valves causing a condition known as Endocarditis...that can actually cause destruction of the heart valves," Lesse said. "That either would require prolonged antibiotic therapy or sometimes surgery is necessary to replace the heart valves."
If the patient has an artificial heart valve, the mortality rate can increase to 50 percent, Lesse said, adding that the heart is not the only organ vulnerable once the bacteria are in the bloodstream.
"Once it appears in the bloodstream, it can affect many different organ systems," Lesse said. "It frequently likes to go to bones and joints. It can seed any tissue, really, so you can get abscesses at multiple locations in the body."
Although there have been many advances in the field of medicine, the SAB mortality rate has not significantly improved over the past 30 years.
"There's probably been some mild improvement," Lesse said, "but there hasn't been major increase in survival for the more serious complications."
The researchers are trying to find a correlation between the strain of bacterium and the complications caused by the infection.
"The first thing that we want to do is sort of look at the epidemiology...the clinical characteristics of the patients who have (SAB) in their bloodstream," Lesse said. "The next thing we want to do is...define which ones will have a low, moderate, or high risk of developing complications."
The ultimate goal of the study is to predict the risk levels of patients who are showing the first signs of a SAB infection, according to Lesse.
"We'll be looking to see...by looking at clinical characteristics of the patients and some of the features of those bacteremias, who is going to be at what risk," he said.
This study will differ from previous research as it involves researchers extracting and collecting genetic data from patients who have SAB, then forming a pool of information.
"In all the previous studies...one staph has been considered to be the same as another. We believe that there are more virulent strains and less virulent strains," Lesse said.
The team, including Dr. Joseph Mylotte, professor of medicine, and Stephen Gill, Ph.D., associate professor of oral biology, will work to separate the bacteria into different categories.
"We're actually going to look at the whole genetic architecture of those bacteria that are causing disease," Lesse said.
Lesse believes that his team of researchers might find as many as five or six major groupings of SAB, each with many more strains underneath it.
"I think what we're going to find is perhaps three or four or five combinations of factors within those major types that may predict a worse outcome," Lesse stated.
One strain of SAB, called Methicillin-Resistant Staphylococcus Aureus (MRSA), has already been identified and recently received significant media coverage, Lesse said. Researchers were able to identify this particular type because it was resistant to methicillin, a distinct characteristic that set this bacterium apart from the rest.
MRSA has recently seen outbreaks in several local hospitals and schools. It has been portrayed as a "superbug," resistant to many previously used treatments, according to Lesse.
The research will be carried out in several local hospitals including Buffalo General, Erie County Medical Center and Sisters Hospital. The John R. Oishei Foundation of Buffalo provided the grant that will initiate this study on SAB.
"I think it's very nice of the Oishei Foundation to be able to sponsor local studies," Lesse said. "This will give us a lot of preliminary information to go ahead and try and get larger international grants."
Photo: Courtesy of Laron Fomby
