A study of acute muscle dysfunction with particular reference to dengue myopathy

Area of Science:

• Neurology
• Infectious Diseases
• Rheumatology

Background:

• Acute myopathy presents as acute motor quadriparesis with diverse causes, prognoses, and complications.
• Understanding these variations is crucial for accurate diagnosis, prognosis prediction, and treatment optimization.
• This study investigates the clinical, electrophysiological, and etiological profiles of acute myopathy, focusing on dengue-related cases.

Purpose of the Study:

• To characterize the clinical, electrophysiological, and etiological spectrum of acute myopathy.
• To differentiate dengue-associated acute myopathy from other causes.
• To compare dengue myopathy with hypokalemia versus myositis in dengue patients.

Main Methods:

• A prospective, observational study of 30 patients with suspected acute myopathy and elevated serum creatine kinase (CK).
• Comprehensive clinical evaluation, laboratory tests, and electrophysiological studies were performed.
• Muscle biopsy and histopathological examination were conducted in selected cases, with follow-up at 1 and 3 months.

Main Results:

• Dengue viral infection (14 patients) and hypokalemia (8 patients) were the most frequent etiologies.
• Patients presented with symmetric weakness, predominantly proximal; 8 had poor functional status at presentation.
• Most patients achieved normal functional status (MBI and MRS scores) within 1 month; dengue with hypokalemia showed distinct features.

Conclusions:

• Dengue infection and hypokalemia are leading causes of acute myopathy, typically resolving within one month.
• Favorable outcomes correlate with shorter illness duration, higher MRC scores, better initial disability status, and lower serum CK.
• Muscle biopsy is not a primary diagnostic tool in acute myopathy, proving decisive in less than 20% of cases.