Systemic infections due to Pseudomonas aeruginosa appear to be a problem in patients who have had open heart surgery, extensive burns, severe pyelonephritis, and previous intensive chemotherapy.1-5 It is for this reason that the following cases which responded to vigorous therapy with a combination of agents given by the intravenous route are being presented. If the presumptive diagnosis of acute bacterial endocarditis in one of the patients is correct, it is only the third of the reported cases due to this organism to have survived.1,6-8 Similarly, the case of necrotizing papillitis due to Pseudomonas aeruginosa may be the first to have survived this disease.4
Therapy in each case was based on 2 findings previously reported from this laboratory and by others. The first was potentiation between polymyxin B and oxytetracycline against Ps. aeruginosa, and the second was the potentiation of antibiotics by the addition of relatively large