Moxifloxacin-induced tinnitus in an older adult.

An increased risk of bacterial resistance toward fluoroquinolones and the increased risk of disabling and serious adverse effects prompted the US Food and Drug Administration to recommend limiting fluoroquinolone use to the treatment of community-acquired pneumonia, skin and skin-structure infections, bacterial sinusitis, plague, chronic bronchitis exacerbations, and complicated intra-abdominal infections. We report a case of moxifloxacin-induced tinnitus in an older adult prescribed oral moxifloxacin 400 mg for 5 days for the treatment of acute diverticulitis, due to allergies to nonfluoroquinolone preferred agents. A thorough literature review provided few other reported incidents of this rare and serious adverse event.

Functional characterization of an IgE-class monoclonal antibody specific for the bullous pemphigoid autoantigen, BP180.

BP180 (collagen XVII) is the target antigen in several autoimmune diseases including bullous pemphigoid (BP). Both IgE and IgG class autoantibodies have been shown to be pathogenic in BP; however, studies designed to elucidate the patho-mechanisms mediated specifically by the IgE-class autoantibodies are limited by the low levels (ng/mL) of IgE in human sera. In this report, we developed mouse IgE class monoclonal antibodies (MAbs) against the immunodominant NC16A domain of the human BP180 protein and characterized two of the resultant MAbs, designated 395A5 and 395D2. Epitope mapping studies revealed that both MAbs target segment 2 of NC16A, as was described for IgE and IgG class BP autoantibodies. Also similar to BP IgE, MAb 395A5 showed indirect immunofluorescence labeling of the basement membrane zone (BMZ) of human skin, stimulated histamine release from mast cells when triggered with NC16A, and induced keratinocyte production of IL-8. The 395D2 MAb was also able to trigger antigen-specific histamine release from mast cells; however, in contrast to BP IgE and 395A5, 395D2 did not label the cutaneous BMZ, nor did it induce IL-8 production in keratinocytes. In summary, these studies underscore the importance of functionally characterizing MAbs generated for use in human disease models. The 395A5 IgE class murine MAb was shown to share several key functional properties with the pathogenically active IgE produced by BP patients. We therefore expect that this MAb will prove to be a useful tool for dissecting the mechanisms used by BP180-NC16A-specific IgE antibodies in the induction of BP skin lesions.