Empyema in a patient treated with infliximab: it is not what it seems

Reduced IgG levels can be the result of long term prednisone treatment or chronic infection. 1 Isolated IgG2 subclass deficiency may result in enhanced susceptibility to encapsulated bacteria. 2 Another report suggests an increased susceptibility to invasive pneumococcal disease in homozygotes for MBL codon variants. 3 It is tempting to speculate that the immunomodulating effect of infliximab contributed to the two episodes of thoracic empyema.