Low-Dose Fosfomycin Therapy for Intractable Sinusitis in Asthmatic Patients. A Preliminary Study.

Long-term, low-dose macrolide therapy has been recognized to be effective for intractable sinusitis. However, association with asthma has proved to involve a poor prognosis. Furthermore, patients with asthma often take theophylline, which has potent cardiac toxicity when used with macrolides. Fosfomycin (FOM) demonstrated immunomodulating action similiar to that observed with macrolides and does not enhance cardiac toxicity of theophylline, because it is not metabolized by P450 in the liver. We investigated the clinical efficacy of low-dose FOM therapy for intractable cases of sinusitis in asthmatic patients. After obtaining informed consent from the patients, we administered 1500 mg of FOM (a dose corresponding to 1/2 of the ordinary dose) 3 times daily to the patients. Thirteen patients who had orally taken FOM for more than 3 months were selected and the efficacy of the drugs was evaluated. Remarkable improvement was noted in 4 cases, moderated improvement in 6 cases, and slight improvement in 3 cases. No abnormal changes in the electric cardiogram (ECG) were found in any of the 12 cases examined, and no adverse reactions were observed in the circulatory organs in any case. Low-dose FOM therapy was suggested to be effective against intractable sinusitis cases complicated with asthma. Low-dose FOM therapy may have a role as an adjunct to medical treatment for intractable sinusitis in asthmatic patients.