SHML

Sinus histiocytosis with massive lymphadenopathy (SHML), also known as Rosai-Dorfman disease, is a disorder of unknown cause.

Synopsis

 bilateral cervical lymphadenopathy, fever, leukocytosis and polyclonal gammopathy
 nodal histiocytosis
 bilateral cervical lymphadenopathy
 emperipolesis
 S100+ CD1a- macrophages

Etiology

 rare germline mutations TNFRSF6 coding for FAS protein (CD95/ApoI)
 autoimmune lymphoproliferative syndrome (ALPS) (15958855)

Localization

 lymph node (nodal SHML)
 extranodal SHML

• hean and neck (15724744, 14707706, 11397505, 10579239)
  • facial skin and muscles
  • orbit (8958550, 7617835, 2712475)
  • paranasal sinuses
  • nasal fossae (8556983)

• intracranial SHML (15581022, 8638205, 2737663)
  • epidural SHML (7327432)

• uveitis and subconjunctival masses (12479625)
• breast (10740798, 10740798)
• pancreas (10370692)
• cutaneous SHML (10494712) and diffuse muco-cutaneous SHML (9870677)
• intramedullary spinal cord SHML (9067506)
• renotesticular SHML (9031615)

Associations

 autoimmune lymphoproliferative syndrome (ALPS) (15958855)
 HIV infection (9818538, 1926767)
 HHV6 infection (1321861)
 malignant lymphoma (15468978) +/- same lymph node (10786808)

• diffuse large B-cell lymphoma (15468978)
• follicular lymphoma
• nodular lymphocyte predominant type Hodgkin lymphoma (NLPHL) (8522313)

 generalized AA amyloidosis (10836304)
 rare occurrence in identical twins (ALPS ?) (3345128)
 idiopathic hypereosinophilic syndrome (3606023)

Differential diagnosis

 autoimmune lymphoproliferative syndrome (ALPS) (15958855)
 Toxoplasma lymphadenitis (nodal toxoplasmosis) (15291364)

References

 Foucar E, Rosai J, Dorfman R. Sinus histiocytosis with massive lymphadenopathy (Rosai-Dorfman disease): review of the entity. Semin Diagn Pathol. 1990 Feb;7(1):19-73. PMID: 2180012