<prompt> Answer this question truthfullyWhat classification does Histiocytosis fall under?  <response>: <reason> There are competing systems for classifying histiocytoses. According to the 1999 classification proposed by the World Health Organization, they can be divided into three categories. . However, the classifications in ICD10 and MeSH are slightly different, as shown below:Types of LCH have also been known as Eosinophilic Granuloma , Hand-Schuller-Christian Disease , Letterer-Siwe Disease , and Histiocytosis X . See LCH history for details. 