An 8 year old child diagnosed with Langerhans cell histiocytosis. Bone involvement is seen. All of the following are true about Langerhans cell histiocytosis, EXCEPT:

Exophthalmos is present in only 10% to 30% of cases of Langerhans cell histiocytosis. It may be unilateral or bilateral and is due to retroocular bone infiltration by Langerhans cells. Langerhans cell histiocytosis is a disease of childhood. Letterer-Siwe disease is the prototype of the acute, disseminated, multisystemic form that usually appears in infants or newborns. The disease can occur in individuals of any age and can also be congenital, but is most common in children aged 1-3 years. Ref: Gelmetti C. (2012). Chapter 147. Cutaneous Langerhans Cell Histiocytosis. In L.A. Goldsmith, S.I. Katz, B.A. Gilchrest, A.S. Paller, D.J. Leffell, N.A. Dallas (Eds), Fitzpatrick's Dermatology in General Medicine, 8e.