Acute Quadriplegic Myopathy Also known as “critical illness myopathy.” Corticosteroids, nondepolarizing neuromuscular blocking agents, or both considered the prime inciting factors. Condition may appear in critically ill patients without exposure…
Botulism and Antibiotic-Induced Neuromuscular Disorders Botulism Toxin blocks nicotinic and muscarinic cholinergic synapses by impeding presynaptic release of acetylcholine. Blocks fusion of vesicles with surface membrane. Epidemiology: toxin produced by…
Lambert-Eaton Myasthenic Syndrome Lambert-Eaton myasthenic syndrome (LEMS): autoimmune disease of peripheral cholinergic synapses. Small-cell lung carcinoma in 60%; other tumors in 7%. Neurologic symptoms precede those of tumor. Pathogenesis: antibodies…
Myasthenia Gravis Disorder of neuromuscular transmission from antibody-mediated attack on nicotinic AChR at neuromuscular junctions. Fluctuating weakness improved by inhibitors of cholinesterase. Etiology and Pathogenesis Polyclonal IgG antibodies to AChR…
Syringomyelia Tubular cavitation of spinal cord, usually cervical, then other segments; more frequent in men; sometimes familial. Onset age 20 to 40. Slow progression; more rapid if brainstem affected (syringobulbia)….
Hereditary and Acquired Motor Neuron Diseases Definitions Diseases characterized by progressive degeneration and loss of motor neurons in spinal cord, motor nuclei of brainstem, motor cortex, or all three sites….
Hereditary and Acquired Spastic Paraplegia Hereditary Spastic Paraplegia Multiple inherited syndromes with prominent progressive leg weakness and spasticity. Complicated forms accompanied by additional clinical findings (Table 118.1). Genetics Genetically heterogeneous….
Tardive Dyskinesia and Other Neuroleptic-Induced Syndromes Adverse effects of drugs blocking D2 dopamine receptors (Table 117.1), especially antipsychotic agents (phenothiazines, butyrophenones); metoclopramide, flunarizine, cinnarizine. Likelihood of these adverse effects for…
Progressive Supranuclear Palsy Symptoms and Signs Usually present: pseudobulbar palsy (emotional lability), supranuclear ocular palsy (vertical gaze), square-wave jerks, extrapyramidal rigidity, gait ataxia, loss of postural reflexes, dementia. Early: falls….
Parkinsonism Characterized by any combination of: tremor at rest, rigidity, bradykinesia (slowing of movements), hypokinesia (less frequent spontaneous movements), flexed posture, loss of postural reflexes, “freezing” (motor block). Categories: idiopathic,…
