Dual infection of Mycoplasma pneumoniae and Chlamydophila pneumoniae in patients with atopic predispositions successfully treated by moxifloxacin.

We report two cases of dual infection with Mycoplasma pneumoniae and Chlamydophila pneumoniae complicated by atopic dermatitis or allergic rhinitis. After exacerbations of atopic eczema or rhinitis, both patients presented a nocturnal fever with persistent cough for more than two weeks. Although the use of susceptible antibiotics, such as minocycline or azithromycin, failed to work, moxifloxacin completely resolved their prolonged symptoms shortly after the administration together with a dramatic improvement of the atopic symptoms. Since the patients in question were predisposed to atopic disorders and their lymphocytes were hypersensitive, an immunological response was thought to be easily triggered by the organisms. Additionally, due to the lymphocyte-stimulatory nature of M. pneumoniae and C. pneumoniae, enhanced immunity was likely to be involved in the pathogenesis. The immunomodulatory property of moxifloxacin was thought to repress the increased lymphocyte activity, and thus facilitated complete remission of the disease.