Lyme Disease and the Eye
By Michael J. Dodd, MD
Lyme disease is an infectious disease which was first described in Old Lyme, Connecticut, in 1975. It is caused by a spiral-shaped bacteria (spirochete) called Borrelia burgdorferi. This organism is transmitted to humans by a deer tick, Ixodes scapularis. The deer tick actually gets the bacteria from small rodents, but since the tick follows deer populations and can also bite people, it is the vector for the infection.
The tick is tiny and often missed when it first bites the skin. As it expands with blood, it becomes more obvious. If the tick is removed in the first day or two, the Lyme infection may be avoided. Many patients who become infected may not realize it. Some patients get a round, red, circle at the site of the bite on the skin called a “bull’s eye rash.” The medical term is “erythema migrans.” From this site the bacteria can spread through the blood stream to anywhere in the body. Organisms have been found in the heart, joints, nervous system and eyes. Interestingly, these ticks can carry other infectious bacteria; it is estimated that as many as 40 percent of patients infected with Lyme may also have other infections transmitted by the same tick. This can complicate the diagnosis of Lyme disease.
Patients can present a myriad of symptoms to a doctor. Most often patients complain of joint pain, but other symptoms include fatigue, shooting pains, numbness and tingling, signs of fibromyalgia, memory loss and emotional changes. Eye findings are not a common presenting symptom. However, Bell’s palsy, or “facial nerve palsy” is the most common eye finding. This shows up as a motor weakness of the facial muscles on one-half of the face. Patients cannot close their eye on that side and severe dry eye may develop. As many as 25 percent of new-onset Bell’s palsy cases may be caused by Lyme disease. Other eye findings include; red eye (conjunctivitis or keratitis), uveitis (inflammation inside the eye), vision loss, optic nerve inflammation and inflammation of the retina (neuroretinitis).
If a patient comes to a doctor with a history of the “bull’s eye ring,” a tick on the skin and joint problems, the diagnosis can usually be made without difficulty. If the tick is removed within 72 hours and antibiotics are given promptly, the Lyme infection can likely be avoided. Lab studies are not typically positive unless the infection has been present for several weeks. Late in the disease, the diagnosis may be difficult, especially if there is no history of a tick bite and no history of a rash. For this reason Lyme disease is often referred to as a “masquerade syndrome,” since it can trigger so many variable symptoms. Long-term antibiotic therapy may be necessary for patients who are diagnosed late in the disease.
Prevention may be the best “treatment.” If you live in areas endemic (geographically prone) to the disease, and Maryland is such an area, you should be cautious in the woods and even the backyard. Wear long sleeve shirts, a hat, long trousers (preferably tucked in the socks) and gloves if doing yard work. Check your pets periodically for ticks and remove them if found. If you see a tick on your skin and develop a rash at the site after removal, get to your physician as soon as possible for evaluation and treatment.
Spring is the season for deer. Beware!
Dr. Dodd, an ophthalmologist, practices at Maryland Eye Associates located in Annapolis and Prince Frederick. He also is an instructor at the University of Maryland Department of Ophthalmology. He can be reached at 410.224.4550 or [email protected]