[The role of MRI in the early diagnosis of pyomyositis in children]. / Papel de la resonancia magnética en el diagnóstico precoz de la piomiositis en niños.

OBJECTIVE: To evaluate the role of MRI in the early diagnosis and therapeutic assessment of pyomyositis. MATERIAL AND METHODS: We reviewed the cases of 11 patients with proven pyomyositis presenting from January 2002 to March 2006. We describe the characteristic findings at plain-film radiography, ultrasound, and MRI, as well as the clinical presentation and laboratory findings. RESULTS: The mean age of presentation was 10 years (range 3-14 years); there was a male predominance (7 cases). Only 4 patients had predisposing conditions. The most common clinical symptom was fever (9 cases). The most common laboratory findings were elevated erythrocyte sedimentation rate (10 cases) and leukocytosis (8 cases). Plain-film and US findings were nonspecific in all cases. Scintigraphy was positive in 4 cases. MRI showed osteomuscular involvement in all cases and enabled the abscesses to be identified. CONCLUSIONS: Pyomyositis is a primary bacterial infection of skeletal muscle. In recent years pyomyositis has increasingly been diagnosed even in patients without predisposing factors. There is a male predominance. Imaging is essential for the diagnosis of the pyomyositis, and radiologists play a crucial role in the early diagnosis of this infection. MRI is the imaging method of choice for characterizing the infection.

Papel de la resonancia magnética en el diagnóstico precoz de la piomiositis en niños / The role of MRI in the early diagnosis of pyomyositis in children

Objetivos. Valorar el papel de la resonancia magnética (RM) en el diagnóstico precoz y el manejo terapéutico de la piomiositis. Material y métodos. Revisión retrospectiva de 11 casos de piomiositis, vistos entre enero de 2002 y marzo de 2006. Se analizan los hallazgos en radiología simple, ecográficos y por RM, así como la presentación clínica asociada. Resultados. La edad media de presentación fue de 10 años, con predominancia masculina en 7 casos. Sólo 4 de nuestros pacientes presentaron antecedentes de interés. El motivo de consulta más común presentado en 9 de los pacientes fue fiebre. Los hallazgos analíticos al ingreso fueron aumento de la velocidad de sedimentación globular (VSG) en 10 casos y leucocitosis en 8. Las radiografías y la ecografía resultaron inespecíficas en todos los pacientes evaluados, y la gammagrafía resultó positiva en 4 casos. La RM mostró afectación osteomuscular en todos los pacientes y permitió la identificación de abscesos. Conclusiones. La piomiositis es una infección bacteriana que aparece en nuestra sociedad incluso sin factores predisponentes, con predominancia masculina, en la que el radiólogo desempeña un papel fundamental para realizar un diagnóstico precoz de la misma, siendo la RM la técnica de elección para caracterizar la infección

Objective. To evaluate the role of MRI in the early diagnosis and therapeutic assessment of pyomyositis.Material and methods. We reviewed the cases of 11 patients with proven pyomyositis presenting from January 2002 to March 2006. We describe the characteristic findings at plain-film radiography, ultrasound, and MRI, as well as the clinical presentation and laboratory findings. Results. The mean age of presentation was 10 years (range 3-14 years); there was a male predominance (7 cases). Only 4 patients had predisposing conditions. The most common clinical symptom was fever (9 cases). The most common laboratory findings were elevated erythrocyte sedimentation rate (10 cases) and leukocytosis (8 cases). Plain-film and US findings were nonspecific in all cases. Scintigraphy was positivein 4 cases. MRI showed osteomuscular involvement in allcases and enabled the abscesses to be identified.Conclusions. Pyomyositis is a primary bacterial infectionof skeletal muscle. In recent years pyomyositis has increasingly been diagnosed even in patients without predisposing factors. There is a male predominance. Imaging is essential for the diagnosis of the pyomyositis, and radiologists play a crucial role in the early diagnosis of this infection. MRI is the imaging method of choice for characterizing the infection