Adult-onset Chronic Recurrent Multifocal Osteomyelitis with High Intensity of Muscles Detected by Magnetic Resonance Imaging, Successfully Controlled with Tocilizumab

• Published in: Internal Medicine Vol. 56; no. 17; pp. 2353 - 2360
• Main Authors: Hasegawa, Eriko, Nozawa, Yukiko, Nakano, Masaaki, Narita, Ichiei, Nakatsue, Takeshi, Sato, Hiroe, Wada, Yoko, Kuroda, Takeshi, Umezu, Hajime, Suzuki, Yoshiki, Saeki, Takako, Ito, Tomoyuki
• Format: Journal Article
• Language: English
• Published: Japan The Japanese Society of Internal Medicine 01.01.2017; Japan Science and Technology Agency
• Subjects: Adult; Age Factors; Antibodies, Monoclonal, Humanized - therapeutic use; Case Report; Children; Chronic Disease; chronic recurrent multifocal osteitis (CRMO); Diaphysis; Differential diagnosis; Humans; Inflammation; Interleukin 6; Internal medicine; Leg; Legs; Magnetic resonance imaging; Male; Middle Aged; Muscles; Muscles - diagnostic imaging; Muscles - pathology; Muscular Diseases - diagnostic imaging; Muscular Diseases - drug therapy; Muscular Diseases - pathology; myositis; NMR; Nuclear magnetic resonance; Osteomyelitis; Osteomyelitis - diagnostic imaging; Osteomyelitis - drug therapy; Osteomyelitis - pathology; Pain; Polyarthritis; SAPHO syndrome; Sclerosis; Tibia - diagnostic imaging; Tibia - pathology; tocilizumab; osteomyelitis; tocilizumab; polyarthritis; chronic recurrent multifocal osteitis (CRMO); SAPHO syndrome; myositis
• ISSN: 0918-2918; 1349-7235; 1349-7235
• DOI: 10.2169/internalmedicine.8473-16

Chronic recurrent multifocal osteomyelitis (CRMO) is an autoinflammatory bone disorder that generally occurs in children and predominantly affects the long bones with marginal sclerosis. We herein report two cases of adult-onset CRMO involving the tibial diaphysis bilaterally, accompanied by polyarthritis. Magnetic resonance imaging (MRI) showed both tibial osteomyelitis and high intensity of the extensive lower leg muscles. Anti-interleukin-6 therapy with tocilizumab (TCZ) effectively controlled symptoms and inflammatory markers in both patients. High intensity of the lower leg muscles detected by MRI also improved. These cases demonstrate that CRMO should be included in the differential diagnosis of adult patients with bone pain, inflammation, and high intensity of the muscles detected by MRI. TCZ may therefore be an effective therapy for muscle inflammation of CRMO.