Positive Test

Trumbull’s flow cytometry lab aids pathologists

By Aisling Maki

An anxious patient awaits the test results of every specimen examined at Trumbull Labs LLC.

Tammie Summers, front, works with director Bonni Hazelton, and Donna Wilson in the flow cytometry lab at Trumbull Laboratories. (Photo: Lance Murphey)

The diagnostic process is a delicate, meticulous one, and the Memphis company, located at 7550 Wolf River Blvd., prides itself on providing clinicians with accurate and definitive diagnostic results as quickly as possible.

Trumbull Laboratories, a state-of-the-art anatomic pathology laboratory that processes nearly 300,000 slides annually, offers histology and cytology tests and services, but the company’s most specialized service may be its flow cytometry laboratory.

“Their work is very unique; it’s a subspecialty of a subspecialty,” said Trumbull Laboratories executive director Norman Hill.

The technique examines cells – obtained from specimen types such as peripheral blood, bone marrow, fluid, needle aspirate and tissue, and disrupted into single cells – to diagnose T-cell disorders, leukemias, lymphomas, myelodysplasia and multiple myeloma.

“The volume is relatively small, but the value is that it’s adding information to the overall diagnostic process,” said Hill, who has more than 25 years of experience in health care administration. “Without that, the pathologist is simply not as confident with the process. It really adds an extra value to the entire diagnostic and interpretation process.”

The technique uses a machine called a flow cytometer to examine individual cells maintained in a specific anticoagulant that preserves the surface of the cells.

Tissues are preserved in a culture medium and placed through a mesh tool to obtain a single-cell suspension.

While a histology lab can look at larger pieces of tissue, such as muscle or heart tissue, flow cytometry is more detailed in the sense that cells must be disrupted into a single-cell suspension.

The flow cytometer, connected to a digital computer, is capable of analyzing thousands of cells in an instant.

“When we’re running our specimens, we run them on medium instead of a very high flow rate, and it depends on how dense your concentration is, but the machine has the capability of doing 10,000 per second,” said flow cytometry laboratory director Dr. Bonnie Hazelton.

Prior to the machine’s invention, pathologists would have had to examine cells on slides under a microscope.

“It’s saving a lot of time, and you’re gaining a lot more information, as well,” said Hazelton, who has more than two decades of experience working in a flow cytometry laboratory.

The results, showing cell markers and specific antibodies, are sent to on-site pathologists for further diagnostic evaluation.

“You may have some odd cells that are in a different position, and you may want to look at those,” Hazelton said. “We have set profiles, so the physicians know exactly what they’re looking at and they can make their determination.”

Her team also works with Baptist Memorial Health Care through its stem cell program, in which the stem cells of a patient, typically a cancer patient, are collected to later be transplanted back into their system.

“We measure the stem cells here and figure out how many the patient has,” Hazelton said. “Then they start getting a calendar ready for high-dose chemotherapy. And because the dose is so high, it’s going to wipe out their bone marrow and immune cells, and we give them back their stem cells to repopulate the marrow.”

Trumbull Laboratories’ pathologists are located down the hall at Pathology Group of the Mid-South, the partner group that founded Trumbull Labs in 1998.

PGM has a medical staff consisting of an internal medical doctor and about a dozen pathologists, medical doctors specializing in the interpretation and diagnosis of diseases in tissues and body fluids, who typically undergo five to seven years of additional training after medical school.

“Trumbull is completely a separate entity, but it works in concert with Pathology Group of the Mid-South for the final service,” Hill said. “The physicians who own PGM also own a part of Trumbull Laboratories, so there is common ownership, but neither entity owns the other. Each stands alone.”

Hill said the flow cytometry lab is operated by highly specialized medical technicians, and that Hazelton “has very unique expertise in this specialty and we’re very blessed to have her at the helm of that laboratory. She’s done a wonderful job.”

He’s also pleased with the fact that the flow cytometry laboratory has provided Trumbull Laboratories the opportunity to participate in clinical studies.

“Through the flow cytometry laboratory, we’re able to participate with some companies for research and development purposes,” Hill said. “It’s always nice to be more on the cutting edge of some of the advances in medicine and technology for medical purposes. The flow laboratory allows us an opportunity to do that and that’s been a very nice feature.”