Effect of Betamethasone in combination with antibiotics on Gram positive and Gram negative bacteria

Betamethasone is an anti-inflammatory steroid drug used in case of anaphylactic and allergic reactions, of Alzheimer and Addison diseases and in soft tissue injuries. It modulates gene expression for anti-inflammatory activity suppressing the immune system response. This latter effect might decrease the effectiveness of immune system response against microbial infections. Corticosteroids, in fact, mask some symptoms of infection and during their use may occur superimposed infections. Thus the use of glucocorticoids in patients with sepsis remains extremely controversial. In this study we analyzed the in vitro effect of commercially formulation of betamethasone (Bentelan) on several Gram positive and Gram negative bacteria of clinical relevance. It is found to be an inhibitor of the growth of most of the strains examined. Also the effect of betamethasone in combination with some classes of antibiotics was evaluated. Antibiotic-steroid combination therapy is, in such cases, superior to antibiotic-alone treatment to impair bacterial growths. Such effect was essentially not observable at all on Staphylococcus aureus or Coagulase Negative Staphylococci (CoNS).