Pseudomonas Infection in Tuberculous Patients: Its Prevention and Treatment with Sulfamethoxazole

¹ Staff Physician, Howard C. Marcy Hospital

The emergence of Pseudomonas aeruginosa in 30 out of 41 hospitalized patients under chemotherapy for pulmonary tuberculosis followed broad-spectrum antibiotic treatment of other secondary pneumonic infections. Fulminant Pseudomonas pneumonia rapidly developed in 27 with cavitary disease.

Specific treatment with colistimethate failed to arrest the Pseudomonas infections or to eradicate the pathogen, except in two patients (neither with cavitary lesions) who showed clinical improvement.

Sulfamethoxazole was given to the remaining 28 patients at an initial dose of four tablets (2 gm), then two tablets (1 gm) t.i.d. for two weeks. The results were: complete eradication of Ps aeruginosa from sputa, together with spectacular clinical improvement in 25 (including two critically ill patients).

A controlled comparative study of 40 newly admitted patients—all with cavitary tuberculosis and secondary nontuberculous pneumonitis—demonstrated the test-drug's prophylactic efficacy as follows: the emergence of Ps aeruginosa was prevented by sulfamethoxazole added to indicated antibiotics in 20 patients; in the 20 controls given antibiotics alone, seven cases of Pseudomonas infection developed. Subsequently, a two-week course of sulfamethoxazole cleared the seven secondary Pseudomonas infections.

While this series was small, the results justify the conclusion that sulfamethoxazole is highly effective both in the prevention and treatment of pneumonic infections due to Ps aeruginosa. Its use against antibiotic-resistant strains of this pathogen may be life-saving in patients with chronic chest diseases complicated by secondary Pseudomonas infection.