Hypersensitivity to inhaled TOBI following reaction to gentamicin

Cystic fibrosis (CF) is the most common autosomal-recessive disease in Caucasians. Colonization with Pseudomonas aeruginosa (P. aeruginosa) of the CF airways causes deterioration of pulmonary status. TOBI (Tobramycin solution for inhalation) is an inhaled antibiotic that can improve the pulmonary disease. We report on a 9-year old boy with CF who developed a rash following a course of IV gentamicin. The rash resolved after its discontinuation. However, the rash returned all over his body, with the start of inhalation of TOBI therapy. We desensitized the patient using escalating doses of inhaled TOBI. He tolerated the procedure well, and continues to be on TOBI 9 months after desensitization on a once-a-day regimen.