Ehrlichiosis

One day late last June, my wife, Betty, began complaining of feeling tired and a constant stomach pain. 

There are two things you should know about Betty:  first, that she is not a ‘complainer’.  If anything, she is the kind of person who doesn’t speak up even when she is freezing or about to have heat stroke.  Second, she has enormous energy.  Feeling ‘tired’ is not normally a part of her vocabulary.

When this condition persisted into a third day, I pushed her to go see her doctor (something else she does not do willingly).  Betty’s internist did an examination and then sent her down for blood work.  When Betty returned, her internist was wearing a surgical mask and handed one to Betty.

My wife's home away from home
for four days and three nights

“I’m calling for an ambulance and sending you to Brigham & Women’s,” the doctor said.  “Your white blood cell count is down to 20% of normal.  Until then, you’re in complete isolation.”

An hour later, Betty was admitted to Brigham & Women’s Hospital where she was put in an isolation room.  I was allowed to drive her into Boston, but that was the extent of the concessions to her dignity.  For the next two days, she was poked, prodded, and subjected to every conceivable test by a battery of specialists.  She was, for lack of a better description, “an interesting case” because there was no ready explanation for her extremely low white blood cell count.

If you are conversant with diseases and markers for them, you know that a low white blood cell count is closely tied to leukemia.  Brigham & Women’s is next door to the Dana Farber Cancer Institute and connected to it by a host of passages through which passed oncology interns and residents eager to do bone biopsies.  Fortunately, Betty exhibited none of the other symptoms and so remained in the hands of the infectious disease people.

Ehrlichiosis bacterium

On her third day, she was visited by yet another specialist, who had heard of her condition and wanted to know more.  He spoke with Betty for half an hour, determining that she was an avid gardener who spent a lot of time outdoors in multiple gardens.  Betty also said that she occasionally found ticks on her body but removed them promptly and had seen no rash.  The specialist asked an odd question: if Betty had recently been to the Gulf Coast.  Betty said, “no”.

“I think I know what’s wrong with you,” he said.  “I think you’re the sixth case of Ehrlichiosis I’ve diagnosed this year.”

Then, he said something scary:  “If I’m right, doxycycline will kill the bacteria that are shredding your white blood cells and we’ll see some improvement within 24 hours.  But, if I’m wrong, the doxycycline will mask other markers and make it harder to find the right infection diagnosis.  What do you want to do?”

Another vial of blood was drawn and Betty started on doxycycline.  It would take a week for the results to come back.  It confirmed that Betty had contracted a rare disease: Ehrlichiosis. 

Double-click to see this chart at a
more readable size.  The nymph
deer tick is the second smallest

Ehrlichiosis, or more specifically, Human monocytic ehrlichiosis, is a tick-borne disease seen, when it is seen at all, in Texas and Arkansas (hence the question about whether Betty had been on the Gulf Coast recently).  There, it is carried by the Lone Star tick and infects a few thousand people each year. 

The good news is that Ehrlichiosis responds to doxycycline, the same drug that is used to treat Lyme Disease.  Betty’s white blood cell count began climbing within 24 hours and she was released (after four days and three nights) to complete her recuperation at home.

The bad news is that Ehrlichiosis takes a well-read infectious disease specialist to spot and, even if Ehrlichiosis is suspected, there’s no ‘quick test’ for it, as there is with Lyme Disease.  Moreover, the absence of a rash is not at all uncommon; in fact, it occurs in fewer than half the cases.  Betty had the muscle aches (her stomach) and malaise that are common symptoms, but not the chills and fever or nausea that are the most common ones.

As the specialist explained it, the scariest part of Ehrlichiosis is that it is so hard to diagnose.  The bacteria invade the blood stream and begin attacking white blood cells.  The infected person gets sick but there’s no clear indication of what’s wrong.  In the meantime, the person’s immune system is badly compromised, and a hospital is a terrific place to pick up additional bugs.  As the infected person picks up those secondary infections, they’re treated for them, but without treating for the underlying ehrlichi bacteria.  In a ‘good’ outcome, the patient comes down with a secondary infection that is treated with doxycycline.  In a bad outcome, the secondary infections keep piling up and the patient dies; the underlying diagnosis never made.

The second scariest part of Ehrlichiosis is that researchers are still unclear as to how long a human has to come into contact with an infected tick.  For Lyme, it’s 24 to 48 hours.  Betty never noticed a tick and did not remove one in the week before her symptoms appeared. She is meticulous about showering.  Could it be that even a brief contact with an infected tick is sufficient?

And, here’s another scary footnote: even after Betty’s white blood cell went back to normal, the lack of strength and continuing tiredness continued for several months.  Those symptoms are common after-effects of the disease.

A month after Betty was released from the hospital, researchers from the Mayo Clinic formally reported their findings in the New England Journal of Medicine that a previously unidentified strain of the ehrlichia bacteria had infected deer ticks in Wisconsin and Minnesota, and were spreading the disease to humans, with 24 cases confirmed.  The report, however, made no mention of New England as a target.

So, call this a warning.  If you garden in New England, there’s a new, very nasty bug out there to be wary of.  Ehrlichiosis has joined Lyme Disease, babesiosis, and anaplasmosis as a reason to slather yourself with tick repellents, and to wear clothing that gives ticks fewer point of contact.