Berton Roueche - The Medical Detectives Volume I

B. microti turns up as a tenant of I. dammini a little more often than R. rickettsii does of D. variabilis .

The other disease that I. dammini may harbor is Lyme disease. Lyme disease is rarely fatal, but unless it is promptly diagnosed and appropriately treated its victims may recover from its acute assault only to give way later to a variety of debilitating chronic ills. I have encountered I. dammini only once, a couple of years ago, and, like my first tick, it was attracted to my wife. She found it settled on, but fortunately not attached to, her thigh after a walk in a weedy pasture. She lifted it off and showed it to me in the palm of her hand. It was a tiny thing.

I. dammini is commonly described as about the size and shape and color of a poppy seed. That, to me, is an exaggeration. My—or my wife's—tick was about the size and shape and color of the period that ends this sentence. My wife supposed at first that it was a little scab or freckle. But it moved, and under a magnifying glass its eight arachnid legs were just visible. We twisted it up in a Kleenex and, on a hunch, took it the next day to a dermatologist in the neighboring village of Southampton—Bernard W. Berger, whom we knew to be an authority on Lyme disease and an active investigator into its nature. Dr. Berger gave it a glance, and identified it not only as I. dammini but also as an I. dammini nymph. It is primarily in the nymph, or middle, phase of its life cycle that I. dammini transmits Lyme disease to humans. It was well, as I say, that our tick had not yet attached itself: at least sixty per cent of I. dammini on eastern Long Island, Dr. Berger told us, are carriers of Lyme disease. That was bad enough. But I learned only the other day that ticks infested with the Lyme-disease organism can also be infested with the organism of babesiosis.

The coincidence of the organisms of Lyme disease and babesiosis in a single obliging tick was first reported in 1983, in the New England Journal of Medicine , by a pediatrician named Edgar Grunwaldt, in general practice on Shelter Island. Shelter Island is a largely wooded island, some thirty square miles in area, that rises between the north and south forks of eastern Long Island. Dr. Grunwaldt was ideally situated to observe the comings and goings and the morbid proclivities of I. dammini .

Although Lyme disease first caught the eye of science in 1976, in the little Connecticut community from which it takes its name, it has, like Rocky Mountain spotted fever, long since outgrown its regional origins. Lyme disease has now been reported in much of the continental United States, with deep and probably ineradicable roots along the upper Eastern Seaboard, in Minnesota and Wisconsin, and in California, Oregon, Utah, and Nevada. There is, however, no place yet known where its roots go deeper than in Dr. Grunwaldt's Shelter Island. In parts of the island, especially in some of its most idyllically pastoral areas, the incidence of infested I. dammini ticks approaches ninety per cent.

"Shelter Island has been a laboratory for much of the investigation into Lyme disease," Dr. Grunwaldt told me in a talk we had at his home one Saturday afternoon—that being a time when he doesn't see patients. "We have the tick in abundance, and we have the disease. We also have babesiosis. As a matter of fact, it was babesiosis that brought me into the Lyme-disease investigation. A paper I wrote that was published back in 1977 in the New York State Journal of Medicine described three cases of babesiosis diagnosed here—the first cases reported in the state—and it came to the attention of Jorge L. Benach, of the state Department of Health and the department of pathology at Stony Brook. He was looking for a good source of ticks for research, and I told him he couldn't do better than here. It was through my interest in Lyme disease that I came to know Allen Steere, of the Yale Medical School. It was Steere and his associates at Yale who pioneered in Lyme disease and published the first report on it. And gave the disease its name. That was in 1976. You may remember the story. It's interesting. A woman in the Lyme area was the real pioneer. Back in the summer of 1972, her child developed a painful arthritis in the knee, and in talking with her friends and neighbors she discovered that a number of other children around there were suffering from the same thing. She apparently knew enough about arthritis to realize that a cluster of cases of a disease like that was unusual. She got in touch with the state health authorities, and Steere heard about the outbreak from them. Arthritis, of course, is only one of the forms that Lyme disease can take, but it was what Steere and his associates first observed. And at first they called it Lyme arthritis. I understand that the old-timers over in East Hampton had a disease they called Montauk knee. Lyme disease has probably been around for a long time. So has babesiosis. There was a disease along the New England coast that was known for many years as Nantucket fever.

"It was chance that brought me here to Shelter Island. I was born and raised in Argentina. I studied medicine in St. Louis, at the Washington University School of Medicine, and trained and practiced in California for about ten years. I married a Long Islander, and we decided to settle in the East. It so happened that Shelter Island needed a doctor. I started practice here in the summer of 1975, and one of the first diseases I saw was what I'm now sure was Lyme disease. I had several patients with a specific rash called erythema chronicum migrans, which has been known and described, particularly in Europe, for a long time. Erythema chronicum migrans is a distinctive marker of Lyme disease. The rash begins with a lesion at the site of the tick bite and slowly spreads outward, in a circular pattern with a red rim. It can be quite large—fifteen or more inches in diameter. I saw the same rash again in the summer of 1976, and I took the trouble to search the literature. Most of the reports I found were Scandinavian, some of them going back to the nineteen-twenties. I found a 1962 paper by three researchers at the University of Helsinki which discussed a possible relationship between Ixodes ticks and the erythema chronicum migrans that was then associated with meningitis. But you can't count on the rash as an infallible clue. For one thing, as we know now, it isn't always present. For another, it only appears several days after the bite and the initial symptoms. In any event, I started treating my cases with antibiotics, and that seemed to do some good. I followed Steere's work as it was published, and that's when I realized that what I was seeing was his Lyme disease. I remember a telephone conversation I had with Steere in 1978. He had decided that in certain cases Lyme disease was self-limiting—that it cured itself and after a while just vanished. That's true, of course, in a way. It seems to go away, but it really just goes underground, and then emerges in a much more serious way. These later complications usually take one of three forms. One, of course, is arthritis of the large joints—most often the knee. Another manifestation is neurological. It can resemble a form of meningitis or the facial paralysis called Bell's palsy. Those early Scandinavian investigators may very well have been seeing our Lyme disease. The third form affects the heart. When Steere assured me that the disease was self-limiting, I stopped using antibiotics. But then he dug deeper and changed his mind. We now know that prompt treatment with a penicillin can generally prevent the later manifestations.

"I was fortunate enough to have a role in the investigation of the cause of Lyme disease. Benach was involved, and Jeffrey Davis, of the Wisconsin Department of Health and Social Services. The laboratory work—the most significant work—was done at the Rocky Mountain Laboratories, in Hamilton, Montana, by a team headed by Willy Burgdorfer, of the National Institute of Allergy and Infectious Diseases. They collected their ticks here on Shelter Island and isolated a spirochetal bacterium that they were later able to demonstrate was the causative organism. It was named for Willy Burgdorfer— Borrelia burgdorferi .