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Stage 2 / Disseminated Infection
Several weeks after the tick bite, hematogenous spread of the spirochete may occur. Although all
regions of the body may be affected, the skin, nervous system, and joints are most commonly involved.
Stage 2 skin lesions occur in about 40 percent of patients. These annular lesions are multiple,
smaller than primary erythema migrans lesions, and are less migratory (Fig. 9).
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Central nervous system involvement at this stage occurs in less than 20 percent of patients and begins weeks to months after the initial tick bite. Neurologic manifestations include acute meningitis, cranial nerve abnormalities, and peripheral neuropathy. Cerebrospinal fluid obtained from patients with meningitis typically reveals a lymphocytic pleocytosis with an average white cell count of 100 cells per cubic millimeter. Unilateral or bilateral facial nerve palsy (Bell’s palsy) is the most frequent cranial nerve abnormality. Peripheral neuritis may be motor, sensory or mixed; electromyographic results often suggest axonal nerve demyelination. |
Intermittent migratory musculoskeletal pain or arthralgias may begin at
this stage. Arthritis is generally more predominant in
Stage 3 disease.
Cardiac involvement occurs in less than 10 percent of patients, but is the most threatening acute complication of Lyme disease. Atrioventricular block is the most common cardiac manifestation and can progress sequentially from first to second to third degree. Progression beyond first degree heart block is more likely if the patient’s PR interval is longer than 0.30 seconds. Heart block gradually resolves spontaneously, but temporary pacemakers may be indicated. |
