Suggest Treatment For Cellulitis In Left Leg

my mother is having rheumatoid arthritis and hypothyroidism. recently she developed cellulitis of her left leg and subsequently septicaemia with massive right sided pleural effusion and pericardial effusion . i am a student in anaesthesia .kindly tell me if she needs treatment for rheumatoid arthritis as we have been told that her arthritis is burnt out. her pleural effusion though decreased still remains with the pericardial effusion. her ejection fraction is 45%