Published in the June 2008 issue of Today’s Hospitalist
BECAUSE HE’S SO BUSY establishing a hospitalist practice, Greg Cummins, DO, doesn’t find much time to pursue one of his passions: mountain biking. But this is the season when another outdoor-related interest “tick-borne diseases “becomes very relevant to his clinical practice.
After being introduced to the topic as an undergraduate, Dr. Cummins wrote a master’s thesis on Lyme disease before medical school. Twenty years later, tick-borne diseases are still a major concern of his. Last year, he co-authored a chapter on the subject in Paul Auerbach’s “Wilderness Medicine, Fifth Edition,” and he lectures and holds grand rounds on the topic.
“This is the time of year,” says Dr. Cummins, who practices with Northland Hospitalists in North Kansas City, Mo., “when we start seeing patients who have failed two or more courses of antibiotics as an outpatient, who are febrile and have some vague disease, like a summer flu.”
One problem with making the diagnosis is that physicians are not suspicious enough of tick-borne diseases. They don’t, for instance, ask patients enough questions about the time they spend outdoors. “That can be just going out on your back patio,” he points out.
Given warming trends and the suburbanization of the U.S., “essentially anybody who isn’t living in a skyscraper apartment is susceptible.” Every deer harbors as many as 3,500 ticks, and each tick lays as many as 5,000 eggs.
While Lyme disease and Rocky Mountain spotted fever remain problems in many parts of the country, Dr. Cummins estimates that ehrlichiosis “which has a 5% mortality rate “is present in 80% of the U.S.
Another mistake physicians make: Asking patients if they’ve seen a tick or tick bite, then ruling a tick-borne disease out of the differential when patients say “no.”
Ticks are often so tiny that they’re easy to miss. Dr. Cummins makes sure to run the labs and start doxycycline, regardless of the results, if the suspicion is there. He cautions that testing for ehrlichiosis is still in its infancy and that physicians often draw titers too soon, before antibodies have a chance to peak.
To protect himself while biking, Dr. Cummins relies on permethrin. (He says DEET is a good option for those who don’t mind chemicals.) And he hopes to eventually make time to study tick-borne diseases as potential bioterrorism agents.
Nineteen species of ticks have been found on reptiles imported as pets, including ticks infected with Crimean-Congo hemorrhagic fever. “I identified one such tick on a python in Savannah, Georgia,” says Dr. Cummins.
For him, that raises fascinating questions about whether tick-borne diseases can be transmitted from one tick to another via an infected host “and whether those diseases can ever make their way to humans as a result.