Rule out corticosteroids, stress, pain, acute systemic infections (viral and bacterial), acquired T lymphocyte deficiency (neonatal infections), immunosuppressive drugs, irradiation, loss of lymph, chylous thoracic effusion (ruptured thoracic duct), lymphosarcoma, enteric
neoplasms, granulomatous enteritis, Johne’s disease (cattle), protein-losing enteropathies, ulcerative enteritis, lymphatic cancer destroying lymph nodes, and hereditary T-cell deficiency.