Benign acute myositis associated with H1N1 influenza A virus infection.

We report the clinical and laboratory features of four children with benign acute myositis observed during the current outbreak of the novel H1N1 influenza A virus. Our findings were similar to those of previous reports for benign acute myositis associated with seasonal influenza. No patients needed oseltamivir, and all of them showed quick recovery without recurrences. In the current H1N1 influenza virus pandemic, the diagnosis of benign acute myositis must be suspected in those children with flu symptoms and difficulty to walk, taking this into account might help avoiding unnecessary studies.