title: Lack of contralateral suppression in transient-evoked otoacoustic emissions in multiple chemical sensitivity: a clinical correlation study.
abstract: Multiple chemical sensitivity (MCS) is a chronic disorder characterized by a variety of symptoms associated with the exposure to chemicals at a concentration below the toxic level. Previous studies have demonstrated peculiar responses in brain activity in these patients with respect to sensory stimuli while the association between chemical sensitivity and other environmental intolerances such as noise sensitivity has been questioned by researchers. In this study, a cohort of 18 MCS patients underwent transient-evoked otoacoustic emission (TEOAE) testing with and without contralateral suppression to evaluate the functionality of the medial olivocochlear (MOC) reflex involved in speech-in-noise sensitivity. Results were compared with an age- and gender-matched control group (n = 20) and correlation analysis with disease onset and quick environmental exposure sensitivity inventory (qEESI) symptom severity scale was performed. Subjects affected by MCS showed statistically significant impairment of MOC reflex, and the onset of the disease and several symptom subscales showed to be correlated to such reduction in some of the frequencies tested. These data suggest that alterations of MOC reflex could be part of the complex features of this disease although more studies are needed to further explore auditory perception disorders in environmental intolerances.
authors.affiliation: Department of Clinical Sciences and Traslational Medicine; Department of Systems Medicine, Neuroscience Unit, University of Rome 'Tor Vergata', Rome, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Micarelli
authors.affiliation: Department of Clinical Sciences and Traslational Medicine, University of Rome 'Tor Vergata', Rome, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Viziano
authors.affiliation: Department of Experimental Medicine, University of Rome 'La Sapienza', Rome, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Genovesi
authors.affiliation: Department of Clinical Sciences and Traslational Medicine, University of Rome 'Tor Vergata', Rome, Italy.
authors.forename: Ernesto
authors.initials: E
authors.lastname: Bruno
authors.affiliation: Department of Clinical Sciences and Traslational Medicine, University of Rome 'Tor Vergata', Rome, Italy.
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Ottaviani
authors.affiliation: Department of Clinical Sciences and Traslational Medicine, University of Rome 'Tor Vergata', Rome, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Alessandrini
mesh_terms: D000328:Adult; D001301:Audiometry, Pure-Tone; D001306:Auditory Pathways / Q000502:physiology*; D001307:Auditory Perception / Q000502:physiology*; D016022:Case-Control Studies; D005072:Evoked Potentials, Auditory / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018777:Multiple Chemical Sensitivity / Q000150:complications / Q000503:physiopathology*; D017084:Otoacoustic Emissions, Spontaneous / Q000502:physiology; D012022:Reflex, Acoustic / Q000502:physiology