Introduction: MYOSITIS is an inflammation of striated muscle tissue. Among its causes, autoimmune diseases are the main ones. However, infectious causes are also incriminated, such as Coxsackie B virus epidemic MYOSITIS. Treponemal MYOSITIS or syphilitic MYOSITIS is, however, exceptional. Its localization or predominance on the facial muscles is even rarer. Case Presentation: We report a case of a facial form of syphilitic MYOSITIS with clinical and radiological study in a 25-year-old patient of Malian origin, presented to the neurology department with a painful facial diplegia that had been evolving for one month. Infectious MYOSITIS is a rare entity. Its symptomatology (myalgia/muscle weakness) may be diffuse or localized, as in the case of our patient. The infectious syndrome may be absent and limited to a flu-like syndrome. Furthermore, direct involvement of a skeletal muscle is rarely reported in the literature. The evolutionary profile is, therefore, little known. Conclusions: Syphilitic MYOSITIS can have complex clinical aspects and constitute a real diagnostic challenge, as reported in our patient's case.

Context: Sporadic inclusion body MYOSITIS (sIBM) is a rare type of juvenile idiopathic inflammatory myopathies (JIIMs). It mainly affects skeletal muscles but can also affect the skin and other organs in the body. Sporadic inclusion body MYOSITIS prevalence in children under 18 years old is very rare. Objectives: This review provides an overview of the evidence of sIBM in children, discusses the possible clinical and pathological features, and explores the proposed pathogenesis. Methods: A literature review of over 44 articles in PubMed and other medical libraries, such as Google Scholar and Web of Science, was carried out using terms such as JIIM, IBM, Inflammatory Myopathies in Children, and Inherited IBM. Two documented reports for sIBM were found, and the rest included the disease pathogenesis, prevalence of inherited IBM, and other myopathies in children. Results: This review discussed the prevalence and incidence of JIIM, in particular sIBM in children. While IBM is typically sporadic, there have been rare cases where it is familial and inherited. Genetic susceptibility factors are believed to play a role in sIBM. Most patients with sIBM are over 50 years old and experience significant weakness in the quadriceps; however, patients with inherited IBM (h-IBM) typically present earlier in adulthood with a distinct pattern of weakness. Sporadic inclusion body MYOSITIS can be misdiagnosed as other forms of myopathies, such as juvenile dermatoMYOSITIS (JDM) or limb-girdle muscular dystrophy (LGMD), during the early stages of the disease. The exact causes of sIBM are still unknown; however, environmental factors, genetic predispositions, and immune dysregulation might contribute to the pathogenesis of the disease. Conclusions: Sporadic inclusion body MYOSITIS is a rare form of JIIMs. Its early diagnosis in children can be challenging due to the presence of other coexisting diseases. Discussions have revolved around potential environmental factors, such as viral infections, specific MYOSITIS-specific antibodies (MSAs), such as anti-Ro52, and possibly certain human leukocyte antigen (HLA) haplotypes. Given the rarity of reported cases of sIBM in children, it is important to encourage further studies to better understand the underdiagnosed instances of this condition.