Shortage of blood proteins (gamma globulins)-, antibodies that are a defence against bacteria and infection. To render bacteria harmless the body needs proteins made by white blood cells, the lymphocytes. Agammaglobulinanaemia can be congenital or occur in later life, in which case the cause is unknown. Sometimes agammaglobulinanaemia is caused by another disease of the white blood cells, such as leukemia or Hodgkin’s disease, which prevent the cells from making the necessary protein for defence against bacteria. Patients with the complaint run a greater risk of contracting diseases such as pneumonia, meningitis and chronic sinusitis.