DNA tests available in a hurry - and cheaply
Joanne Laucius, Canwest News Service
Published: Sunday, April 13, 2008
OTTAWA-A worried mother with a feverish child arrives in the emergency room. The doctor suspects the child, who also complains of a headache, has bacterial meningitis. He orders a lumbar puncture, then starts the child on antibiotics.
The doctor also orders a Gram stain, a test first devised more than a century ago to identify bacteria. The stain suggests the doctor's assessment is correct, but the test is not infallible. More cerebrospinal fluid from the lumbar puncture is sent to the lab to culture it for bacteria.
A few days later, the results are in and it's negative for bacteria. Meanwhile, the patient isn't getting any better.
The doctor suspects the diagnosis is actually viral encephalitis and prescribes an antiviral. The patient improves, but suffers long-term neurological damage because of the delay.
This medical detective story has been simplified. But it illustrates a conundrum of modern medicine - doctors often have to prescribe "on spec."
It was this problem that diverted University of Ottawa medical graduate Dr. Paul Lem from infectious diseases to a new career in business, producing a machine that helps eliminate the guesswork.
Doctors often have to diagnose illnesses based on observation and wait until the lab confirms or denies the diagnosis, says Lem, who was doing a residency in infectious diseases in Toronto before he quit medicine to go into business.
"It's crude," said Lem, now CEO of Ottawa's Spartan Bioscience Inc., which has developed an inexpensive and portable "on demand" DNA analyzer as an alternative to the larger "batch" analyzers used in laboratories.
As it stands, only large laboratories have "batch" analyzers, which can test as many as 96 samples at a time. Lem's idea was small, relatively inexpensive DNA analyzer that could save both patient and doctor time and steps. The Spartan DX is priced at just under $10,000, which Lem believes is the "magic price point" to make the devices attractive to smaller hospitals and research facilities.
"Batch machines are incredible. They're like Ferraris," said Lem. "We're selling Toyota Corollas. But there's more of a market for Corollas."
Karam Ramotar, a microbiologist at Ottawa's General Hospital, says an on-demand analyzer is useful for doing a quick assessment on a very sick patient.
"The idea of using a machine like this is that you can do proper therapy very quickly," said Ramotar, who has been evaluating a Spartan analyzer in his lab.
Tim Karnauchow, a clinical virologist at the Children's Hospital of Eastern Ontario, has two Spartan DX machines in his lab, both donated by the company. He recently completed a series of tests that concluded that the DX is just as accurate as conventional instruments, which cost between $25,000 and $60,000.
"This instrument is a clever development," he says.
Karnauchow sees a use for it when a physician can't afford to wait a day or more for a sample to be tested with a large batch. To a clinical virologist, it's valuable to be able to do a quick test without having to tie up a batch machine, he says.
From the medical system's fiscal point of view, it also makes sense to treat a patient as soon as possible without wasted money or time on an incorrect diagnosis, says Karnauchow.
"If you can give them a definitive diagnosis, you can cut health-care costs," he says.
Spartan is not the first company to try to manufacture and market a "desktop" DNA analyzer, says Lem. But, despite millions in investments, none have succeeded. The difference is that the other analyzers used DNA chips, which are very expensive to fabricate unless they are produced by the millions, he says.
The Spartan analyzer requires a sample of purified DNA, derived from saliva, blood or other bodily fluid. An assay "amplifies" the building blocks of the target gene marker in the sample. The Spartan analyzer works by measuring the presence or absence of fluorescence in the sample.
The most complicated part of the device has been the optics, but being located in Ottawa was an advantage to Spartan, which was able to draw on experienced optical engineers from Nortel and JDS Uniphase, says Lem.
All the funding so far - the company won't say how much except that it is in the "low millions of dollars" - has come from angel investors, mostly in Ottawa and Toronto, says Mark Kershey, the company's vice president of corporate development.
Spartan started product development in June 2006 and spent almost $2 million in research and development, he says. To date, 15 analyzers have been sent to labs and universities to be evaluated.
Lem sees a day when every doctor's office will be able to afford an analyzer and offer more convenience to patients who now have to wait for lab results. He sees another potential market in veterinary medicine. On-demand analyzers might even have a place in combating antibiotic-resistant superbugs by reducing the widespread use of antibiotics when they are unnecessary.
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