A study of muscle involvement in scrub typhus

作者：Kalita Jayantee; Misra Usha K^*; Mani Vinita E; Mahadevan Anita; Shankar Susrala K

来源：Journal of the Neurological Sciences, 2015, 348(1-2): 226-230.

DOI：10.1016/j.jns.2014.12.012

• Scrub typhus
• Myopathy
• Histopathology
• Vasculitis
• Creatinine kinase
• Electromyography

Objectives: Patients with scrub typhus often complain of myalgia, but a comprehensive study on muscle dysfunction is lacking. We therefore report the clinical, electromyographic and muscle biopsy findings in patients with scrub typhus.
Methods: Consecutive patients with scrub typhus were included, and their clinical and laboratory findings were noted. The patients with myalgia or weakness and elevated serum creatine kinase (CK) were considered to have muscle involvement Electromyography (EMG) and muscle biopsy were done in some patients. Patients were treated with doxycycline 200 mg daily for 7 days, and their clinical and biochemical outcome on discharge and one month were evaluated.
Results: 13 out of 33 (39.4%) patients had muscle involvement and their CK levels ranged between 287 and 3166 (859 +/- 829) U/L. EMG revealed short duration polyphasic potentials, and muscle histopathology revealed evidence of vasculitis. There were significant correlations between severity of weakness and CM levels (r = -0.6; p < 0.001), platelet counts (r = 0.4; p = 0.04), duration of illness (r = -0.4; p = 0.01) and disability on discharge (r = -0.4; p = 0.04). Patients with muscle involvement had more severe illness evidenced by a lower Glasgow Coma Scale score (p < 0.001), thrombocytopenia (p = 0.05) and greater disability on discharge (p = 0.007), when compared to those without muscle involvement All the patients had complete recovery following doxycycline therapy, and CM levels also normalized.
Conclusion: Muscle dysfunction was present in 39% patients with scrub typhus. Although muscle histopathology showed evidence of vasculitis, patients responded to doxycycline.

• 出版日期2015-1-15
• 单位河北医科大学