Peripheral nervous system involvement in human and experimental chronic American trypanosomiasis

Area of Science:

• Neurology
• Parasitology
• Pathology

Background:

• Chronic American trypanosomiasis (Chagas' disease) is a significant public health concern.
• The involvement of the peripheral nervous system (PNS) and skeletal muscle in chronic Chagas' disease requires further elucidation.

Purpose of the Study:

• To investigate the electrophysiological and histological changes in the skeletal muscle and PNS of patients with chronic Chagas' disease.
• To characterize these changes in an experimental mouse model of Chagas' disease.

Main Methods:

• Electrophysiological assessments including electromyography (EMG), nerve conduction studies, and neuromuscular junction analysis.
• Histological examination of muscle and nerve biopsies from human patients and infected mice.
• Immunohistochemical analysis of inflammatory infiltrates in affected tissues.

Main Results:

• Approximately 30% of chronic Chagas' disease patients exhibited peripheral neuropathy, characterized by reduced motor units, slow nerve conduction velocities, and impaired neuromuscular transmission.
• Mice models showed similar electrophysiological and histological alterations, including demyelination, axonal loss, and muscle fiber abnormalities.
• Inflammatory infiltrates in both humans and mice were primarily composed of T lymphocytes.

Conclusions:

• The skeletal muscle and peripheral nervous system are significantly affected in chronic American trypanosomiasis.
• Electrophysiological and histological findings provide evidence for neuropathy and myopathy in Chagas' disease.
• The study highlights the utility of the mouse model for understanding Chagas' disease pathogenesis.