Lyme disease is caused by infection with Borrelia burgdorferi which is a spirochete that is transmitted by ticks. The deer tick, Ixodes dammini, is responsible for the disease in most cases. It takes approximately 12 to 24 hours of tick attachment to transfer the spirochetes. There are 3 recognize stages of Lyme disease: Early infection with localized erythema migrans. Disseminated infection. Late stage infection.
The localized response occurs within 1 month of a tick bite. It consist of an erythematous circular region centered around the area of the original tick bite. The erythematous area gradually expands in the center of the lesion becoming more clear creates a bull's-eye appearance. The rash then resolves spontaneously after approximately a month. Not all patients with Lyme disease but developed erythema migrans.
The second stage of the illness is marked by dissemination of the spirochetes throughout the body. Patients develop systemic symptoms including fever, chills, localized adenopathy, fatigue, myalgias, headache, neck and back pain, and additional skin lesions around the body. Cardiac involvement may lead to pericarditis and heart block. Inflammatory arthritis of large and small joints may also occur.
Neurological complications may develop during the second and third stage of infection. Neurological disorders there is associated with the Lyme disease are as follows: Encephalitis/meningitis, myelitis, cranial neuropathies (facial palsy), peripheral neuropathy including mononeuropathies, multiple mononeuropathies, radiculopathy, plexopathy. Also inflammatory myopathy.
Facial neuropathy is the most common neurological manifestation of Lyme disease and is bilateral and about half of cases, which is rare for idiopathic Bell's palsy. Involvement of nerves is frequently asymmetric.
An acute, predominantly motor polyradiculopathy resembling AIDP has been rarely reported with Lyme disease. In a review of 163 patients with Lyme disease, two presented with a severe, acute, AIDP-like polyradiculopathy. Patients present with rapidly progressive diffuse symmetric or asymmetric weakness with areflexia and minimal sensory symptoms. In addition to lower motor neuron involvement, concomitant myelopathic signs have been reported. Some patients experience other systemic symptoms, including epigastric pain, nausea, vomiting, diarrhea, and joint pain.
The late stage of infection is characterized by further destructive inflammatory changes in the joints. The distal extremities develop bluish discoloration of skin (acrodermatitis chronica atrophicans). Spirochetes may be readily cultured from biopsies of these sites. Approximately 50% of patients have numbness, paresthesias, weakness, and cramps in the distal extremities, and proprioception and vibration are reduced as are muscle stretch reflexes.
Examination of the CSF should demonstrate lymphocytic pleocytosis and increased protein in patients with polyradiculitis, cranial neuropathies, and CNS involvement. Immunofluorescent or enzyme length in mid assortment assay may detect antibodies directed against the spirochete in the serum and CSF. Western blot analysis should be performed to confirm a positive ELISA.
Electrodiagnostic studies are suggestive of a primary axonopathy. In a patient with mononeuropathy or multiple mononeuropathies, NCS typically reveal reduced CMAP and SNAP amplitudes. Those with facial nerve paralysis have reduced facial nerve CMAPs and abnormal blink reflexes. The electrophysiological abnormalities are often asymmetric. Needle EMG reveals increased insertional and spontaneous activity in the form of fibrillation potentials and positive sharp waves and decreased recruitment of neurogenic appearing motor unit action potentials. Patient is presenting with a radiculopathy may have normal motor and sensory nerve conduction studies but the EMG is abnormal as above.
Histopathology: Nerve biopsies are not typically performed in patients with Lyme disease and symptoms of neuropathy, but can reveal perivascular infiltration of plasma cells and lymphocytes around small endoneurial, perineurial, and epineurial blood vessels without clear necrotizing vasculitis. Axonal degeneration and secondary demyelination can be seen.
Treatment recommended treatment of facial nerve paralysis is in adults is the combination of amoxicillin 500 mg p.o. 4 times daily plus probenecid 500 mg p.o. 4 times daily for 2 to 4 weeks. Patient allergic to penicillin can be treated with doxycycline 100 mg p.o. twice daily for 2-4 weeks. Children less than 4 years of age can be treated with amoxicillin 20 to 40 mg/kg/day in 4 divided doses for 2 to 4 weeks. If allergic to penicillin, children can be treated with erythromycin 30 mg/kg/day in 4 divided doses for 2 to 4 weeks. Adult patients with other types of peripheral neuropathy are treated with intravenous penicillin 20 to 24 million units/day for 10 to 14 days or ceftriaxone 2 g IV daily for 2 to 4 weeks. Those allergic to penicillin should receive doxycycline 100 mg p.o. twice daily for 30 days. Children with Lyme neuropathy can receive IV penicillin G 250,000 U/kilogram per day in divided doses for 10 to 14 days of ceftriaxone 50 to 80 mg/kg/day IV for 2 to 4 weeks.
VZV infection commonly produces a focal or multifocal sensory neuropathy including pain, sensory loss, and a vesicular rash, in the distribution of involvement of the affected dorsal root ganglia and corresponding root dermatome (shingles). VZV has also been associated with involvement of the anterior horn cells, producing weakness and atrophy, along with sensory symptoms, in the involved root distributions. A more diffuse polyradiculopathy has been reported in several patients with VZV infection. In one case, a 79-year-old man presented with GBS-like rapidly progressive paraplegia, features of demyelination on electrodiagnostic studies, and CSF findings of elevated protein. Additionally, CSF demonstrated a moderate pleocytosis, and VZV was confirmed by PCR. Enhancement of the cauda equina on MRI was also demonstrated. Complete recovery occurred after 6 months.
Diphtheria has become a rare infection since the implementation of routine and booster immunization programs, and adults may be affected more often than children because of the fall in immunity in the adult population. It has been shown that 40% to 50% of adults in the United States may be susceptible to diphtheria. Diphtheria manifests as a febrile illness associated with nasopharyngeal exudates (pseudomembranes). An acute polyradiculopathy similar to GBS has been reported in 10% to 75% of patients with diphtheria. Neuropathic symptoms usually begin within the first 2 weeks following initial infection and manifest in two phases. Initially, bulbar weakness, including swallowing dysfunction and ocular motility deficits, develops and improves a mean of 30 days after onset. Limb weakness and sensory loss, as well as autonomic dysfunction, develop as the bulbar symptoms are improving, peaking at a mean of 49 days after the onset of diphtheria. Respiratory muscles may be involved, requiring mechanical ventilation. EMG demonstrates features of segmental demyelination, including prolonged distal latencies, and CSF may demonstrate elevated protein with a normal or mildly elevated cell count, similar to AIDP. The presence of Corynebacterium diphtheriae on throat culture or with PCR confirms the diagnosis.
Treatment includes penicillin and diphtheria antitoxin. Although diphtheric polyradiculopathy has similarities to GBS, clinical features that should lead to consideration of diphtheria include bulbar and respiratory muscle involvement in the context of minimal or no limb involvement, progression of symptoms over more than a 4-week period, and a preceding fever and sore throat.
Several cases of an acute radiculomyelitis due to Mycobacterium tuberculosis infection have been described. Patients present with rapidly progressive paraparesis along with sphincter dysfunction, Babinski signs, and features of a diffuse meningitis, such as headache and mental status changes. CSF demonstrates a neutrophilic pleocytosis.