NON-EOSINOPHILIC GRANULOMA OF THE SKULL-A HIHERTO UNDESCRED TYPE OF THE RETICULO-HISTIOCYTOSIS OF BONE

Destructive lesions of the skull with bumps occurring as a primary feature in a disease may present a diagnostic problem. The reticulo-histiocytic diseases must be considered. These are classified into following three variants: (1) eosinophilic granuloma of bone, (2) Hand-Schüller-Christian disease, and (3) Letterer-Siwe disease. They are now considered to be clinical gradations of expression of the same basic disorder<SUP>10, 9, 30)</SUP>. We have experienced, for these six years, five cases of reticulo-histiocytosis of the skull. Two of these patients had eosinophilic granulomas, one of which was reported in detail elsewhere<SUP>20)</SUP>, and one had Hand-Schüller-Christian disease. It is the purpose of this report to describe the remaining two cases which, although not clearly corresponding to any one of the abovementioned three variants, are believed to represent a non-lipid, non-eosinophilic reticulo-histiocytic granulomatous disease of the skull. They are hitherto undescribed forms of the entity. It is now evident that Letterer-Siwe disease is the most severe type and eosinophilic granuloma is a milder form, but the two cases of which we wish to discuss here are considered to be as mild or more milder form as eosinophilic granuloma of bone.