the previous term , histiocytosis x , including eosinophilic granuloma of bone , the hand-schuller-christian syndrome and letterer-siwe 's disease , is now more correctly called langerhans ' cell histiocytosis ( lch ) since the infiltrating cell in histiocytosis x both histologically and immunophenotypically is identified as the langerhans ' cell .
C0019621
histiocytosis x
C0023005
langerhans