[A case of acute lymphotic leukemia which was difficult to make a diagnosis of CRMO for moving arthralgia and periarticular swelling].

A girl, 7 years of age, was reported who had been suffered from migratory arthralgia, bone pain and erythematous rash. She had increased inflammatory markers such as C-reactive protein, erythrocyte sedimentation rate, and mild anemia for more than 6 months. In the beginning, she was suspected of having either juvenile idiopathic arthritis or chronic recurrent multifocal osteomyelitis. However, after about 6 months, there were abrupt increases of LDH in serum titers and blast cells were also revealed by bone marrow examination. Upon these findings, she was diagnosed with acute lymphocytic leukemia. Since bone pain and arthralgia bone pain and arthralgia are both indicative of numerous inflammatory disorders such as infectious myelitis, juvenile chronic arthritis, childhood leukemia and malignancies, and auto-inflammatory bone diseases, especially chronic recurrent multifocal osteomyelitis, it is difficult to accurately diagnose right away. For now, these aforementioned inflammatory responses are the sole key findings for clinical investigations. Other than that, there are not enough reports yet to help diagnose incases similar to this. Therefore, it is difficult to differentiate between the disorders above even after blood tests, Ga-scincigraphy, and imaging examinations. Moreover, in the case of childhood leukemia, it was difficult to differentiate these diseases by routine X-ray surveys in the general pediatric fields. The reasons are because there are only a few descriptions on X-ray bone examinations on findings of X-ray bone investigations, and both are usually non-specific. However, according to the pediatric radiology specialists, of which there are only a few in Japan, the imaging results show somewhat abnormal findings could be spotted from the early stage. Through this present case, it is suggested to us that it is important to consult the pediatric radiology specialists in order to speed up the diagnostic process. Furthermore, the accumulation of radiological findings of leukemia in children with bone pain and arthralgia will attribute to an early diagnosis and lead to the resolution of pathogenesis of leukemia.