Common variable immunodeficiency with muscle hypertrophy and myotonia myositis

Abstract

Objective To report the clinical and myopathological features in a patient with common variable immunodeficiency (CVID) with myositis. Methods A 33 years old man suffered from recurrent respiratory infection with fever over 10 years. The symptoms improved after anti-infection therapy. At the same time he presented with fatigue. Two years ago he developed general muscle weakness，hypertrophy and myotonia，especially in the hands, neck and thighs. Genetic test for myotonic dystrophy protein kinase (DMPK) and zinc finger protein 9 (ZNF9) was performed. Laboratory tests, electromyography, muscle ultrasound and muscle biopsy were performed. In addition to standard histological and enzyme histochemical stainings, immunohistochemical method was used with primary antibodies of mouse anti human monoclonal antibodies including CD8 for T-lymphocytes, CD20 for B-lymphocytes, CD68 for macrophages and MHC-Ⅰ for muscle membrane. Results Electromyography revealed myogenic changes and abound with myotonic potentials. There was muscle hypertrophy in muscle ultrasound. Lung biopsy showed chronic inflammatory changes. Serum hypoimmunoglobulin and anemia were found. Muscle biopsy showed muscle fiber necrosis and regeneration with lymphocyte and macrophage infiltration. There were no gene mutations in DMPK and ZNF9 gene. Conclusion Muscle hypertrophy and myotonia appeared in CVID with myositis. Key words: Common variable immunodeficiency; Myotonia; Myositis