General
=========================================================================

• Rare; crystalline material accumulates in cytoplasm of histiocytes; usually kappa light chain origin
  
• Typically associated with disorders that express monoclonal immunoglobulins such as myeloma, lymphoplasmacytic lymphoma, monoclonal gammopathy of undetermined significance

Case reports
=========================================================================

• 51 year old woman with upper lip and cheek tumor (Head Neck Pathol 2012;6:111)
  
• 73 year old woman with tongue mass, chronic rheumatoid arthritis, polyclonal hypergammaglobulinemia (Arch Pathol Lab Med 1998;122:920)

Micro description
=========================================================================

• Histiocytes filled with nonbirefringent eosinophilic crystals
  
• Lymphocytes and plasma cells also present
  

Micro images
=========================================================================

Eosinophilic histiocytes

CD68+

Immunoglobulin stains

Positive stains
=========================================================================

• Crystals are typically monoclonal, immunoreactive with kappa or lambda light chain and gamma heavy chain
  
• CD68+ histiocytes

Negative stains
=========================================================================

• Desmin, muscle-specific actin, myoglobin, S100, CD1a

Electron microscopy images
=========================================================================

Dense crystals

This information is intended for physicians and related personnel, who understand that medical information is often imperfect, and must be interpreted in the context of a patient's clinical data using reasonable medical judgment. This website should not be used as a substitute for the advice of a licensed physician.

All information on this website is protected by copyright of PathologyOutlines.com, Inc. Information from third parties may also be protected by copyright. Please contact us at copyrightPathOut@gmail.com with any questions (click here for other contact information).