Successful management of severe asthma in a young boy with eosinophilic chronic rhinosinusitis who received omalizumab: a case report.

Background: The incidence of chronic rhinosinusitis with nasal polyps has recently increased in Japan and other East Asian countries, and this disease is called eosinophilic chronic sinusitis (ECRS) in Japan. ECRS usually occurs in adults and is frequently accompanied by refractory bronchial asthma. However, its occurrence in children under 10 years of age is rare. Here, we present an unusual case of ECRS complicated by intractable asthma in an 8-year-old boy.

Case Presentation: Oral administration of prednisolone (10 mg/day) initially relieved the ECRS and bronchial asthma, but both returned during prednisolone dose reduction. Because nasal cavity-opening surgery was ineffective, oral administration prednisolone at 10 mg/day was continued. Pancytopenia was observed 16 months after the start of treatment, and the patient was admitted to our hospital. He was diagnosed with refractory cytopenia in childhood, but gradually improved after cyclosporine treatment. Although the dose of cyclosporine was therapeutic for asthma, it did not alleviate the asthma attacks, and the patient's quality of life markedly decreased. We administered omalizumab even though its use was contraindicated by negative results in an inhalable antigen test. After the third administration of omalizumab, the asthma was better controlled and respiratory function improved; however, the nasal symptoms of ECRS persisted. Attempts to relieve these symptoms by increasing the therapeutic dose of omalizumab were only partially successful. We replaced omalizumab with mepolizumab; doing so slightly improved the sinusitis symptoms, but quality of life remained unsatisfactory. We repeated the nasal cavity-opening surgery. After surgery, the asthma and sinusitis were unchanged.

Conclusions: Omalizumab effectively treated the severe combined asthma in a young patient, but its effect on sinusitis was insufficient. More cases and long-term follow-up data are needed to better evaluate the effectiveness of mepolizumab for treatment of ECRS.