"Other" Hematologic Disorders

Question 1

Rosai-Dorfman Disease

Answer 1

• Hallmark is emperipolesis of inflammatory cells by histiocytes, seen best on S100 staining to highlight tissue macrophages

Question 2

Mucopolysaccharidosis type VI (Maroteaux-Lamy syndrome)

Answer 2

Deficiency in Arylsulfatase B

Causes buildup of mucopolysaccharides in lymphocytes, as well as pancytopenia and hypergranulation in neutrophils

The lymphocytes have characteristic tiny fried egg granules