Department: upFront: COMBATING INFECTION
TINY DEER TICKS transport and transmit Lyme disease, an infection that can cause serious and long-lasting problems. This vector-borne illness caused by the spirochete Borrelia burgdorferi can involve the skin, joints, heart, and nervous system.
When Lyme disease is diagnosed and treated early, the patient is likely to recover completely. However, advanced or chronic Lyme disease may cause serious neurologic problems as the infection spreads to the brain, nerves, or spinal cord. Meningitis (infection and inflammation of the membranes that cover the brain and spinal cord), encephalitis (infection and inflammation of the brain), and Bell's palsy (facial paralysis) are possible neurologic complications. Let's review how neurologic complications of Lyme disease develop and what you can do to help the patient recover.
Catching it early
Skin changes may announce Lyme disease. The earliest skin stage is erythema migrans, commonly referred to as a “bull's-eye” rash (see the photo above). Occurring in about 80% of patients with Lyme disease, it appears 3 to 30 days after the tick bite. Along with a skin rash, joint pain, fever, and malaise, signs and symptoms that may indicate neurologic involvement include:
- stiff neck
- light sensitivity (photophobia)
- difficulty concentrating
- poor memory
- emotional lability
- symmetrical distal, nonpainful paresthesia
- asymmetrical back pain
- sensory loss
- weakness and diminished deep tendon reflexes (hyporeflexia).
Even when all these signs and symptoms are present, the patient needs further assessment for a definitive diagnosis of Lyme disease.
Making a diagnosis
If the health care provider suspects Lyme disease (for example, because the patient has a history of a tick bite or has recently stayed in wooded or endemic areas) and the patient develops neurologic signs and symptoms, blood and cerebrospinal fluid cultures will be ordered to rule out other bacterial sources of meningitis. Serology blood tests, such as an arboviral panel, may rule out viral encephalitis. Lyme encephalitis may be mistakenly diagnosed as the more common viral encephalitis and treated with antiviral medications, but these won't eliminate the Borrelia infection.
Although blood tests can often identify Lyme disease, they can't be the sole diagnostic parameter because several weeks must pass before antibodies appear in the blood. Initial tests performed soon after exposure will be negative even if the disease is present; repeat testing is indicated to show increases in antibody. Special immunofluorescent tests can be performed on spinal fluid, but routine Gram stain and culture of the fluid won't show the bacteria.
Treatment options and nursing care
Lyme disease can be treated successfully in its earliest stages with oral antibiotics. If the disease progresses to later stages, the patient requires more intensive therapy. Depending on the stage of disease and his age and overall health, a course of ceftriaxone or cefotaxime is administered I.V. for 14 to 28 days; these antibiotics penetrate the blood-brain barrier.
A patient with acute Lyme encephalitis or meningitis doesn't need isolation, but standard precautions apply. Administer I.V. antibiotic medications as ordered, monitor him for adverse reactions and response to treatment, and perform frequent neurologic assessments.
Family and patient education is vital, particularly if the patient is a child with neurologic complications of Lyme disease. Refer families to user-friendly Web sites such as http://www.kidshealth.org or http://www.mayoclinic.com.
. Accessed July 17, 2007.Centers for Disease Control and Prevention. Lyme disease erythema migrans.
. Accessed November 9, 2007.Fallon BA. Neurologic Lyme disease. 12th Annual Conference on Lyme Disease and Other Spirochetal and Tick-Borne Diseases. April 1, 2007.
. Accessed January 3, 2008.International Lyme and Associated Disease Society. What psychiatrists should know about lyme disease.