Congenital self-healing histiocytosis.

In a typical case of congenital self-healing histiocytosis of the Hashimoto-Pritzker type, the results of an ultrastructural examination of a nodule of a 30-day-old patient showed that about 25% of the cells contained unique phagosomes but no regularly laminated bodies. This case of congenital self-healing histiocytosis is an example of concurrent proliferation of two types of histiocytes (one with and one without Langerhans' granules). Since transitional forms were not observed, this finding might indicate the existence of congenital, self-healing forms of histiocytosis X.