non-Langerhans cell histiocytosis xanthoma disseminatum https://rarediseases.info.nih.gov/diseases/13186/xanthoma-disseminatum https://www.malacards.org/card/xanthoma_disseminatum UMLS:C0043322 Montgomery syndrome MedDRA:10052575 Orphanet:158003 MONDO:0015535 SCTID:399970005 icd11.foundation:1785140754 GARD:0013186 MEDGEN:12178