Secondary immunodeficiencies. There are many possible causes and so it is difficult to obtain exact epidemiological data. It is known that the current epidemics of AIDs and tuberculosis have caused global increases in the condition.
Secondary immunodeficiency is common in people who are hospitalised for:
Drugs - particularly cytotoxic drugs and immunosuppressants.
Viruses, eg HIV.
Malnutrition - the most common cause worldwide.
Metabolic disorders, eg renal disease requiring peritoneal dialysis.
Trauma or major surgery.
Protein loss - for example, due to nephrotic syndrome.