Differential Diagnosis: Lymphopenia

Following are differential diagnoses for patients presented with lymphopenia.

• Acute infection, particularly viral 

• Cytotoxic or immunosuppressive drug (eg, chlorambucil, cyclophosphamide) 

• Destruction/disruption of lymphoid tissue (eg, multicentric lymphoma)

• Immunodeficiency (rare; eg, severe combined immunodeficiency syndrome in basset hounds, Cardigan Welsh corgis, Jack Russell terriers, Frisian water dogs)

• Increased exposure to endogenous corticosteroids

  • Acute illness

  • Hyperadrenocorticism

  • Stress (eg, surgery)

• Increased exposure to exogenous corticosteroids

  • Steroid therapy

  • Contact with steroid creams in household

• Loss of lymphocytes (eg, into intestinal tract with lymphangiectasia, into pleural cavity with chylothorax)

• Whole body irradiation