Download AUDIOLOGICAL MANIFESTATIONS IN PATIENTS WITH VITILIGO

AUDIOLOGICAL MANIFESTATIONS IN PATIENTS
WITH VITILIGO
Dr. Sanjay Munjal*
Ms. Richa Arya**
Dr. Naresh Kumar Panda***
Dr. A.J.Kanwar****
*Tutor & Incharge Speech and Hearing Unit (L – 207)
**Intern BASLP (Student member-ISHA) →applied for……
*** Professor & Head Department of Otolaryngology
**** Professor and Head Department of Dermatology
Address for correspondence- [email protected], [email protected]
Room no.441, Speech and hearing Unit, ENT department
4th floor, New OPD
POST GRADUATE INSTITUTE OF MEDICAL EDUCATION & RESEARCH,
CHADIGARH-160012, INDIA
Paper submitted for 43rd ISHACON
AUDIOLOGICAL MANIFESTATIONS IN PATIENTS WITH VITILIGO
INTRODUCTION
Vitiligo is an idiopathic disease that causes destruction of melanocytes in the
skin, mucous membranes, eyes, inner ear, leptomeninges and hair bulbs (Hann
and Nordlund). Various recent clinical and animal experimental studies support
the premise that the pathogenetic mechanisms of vitiligo could be systemic
events as vitiligo is associated with ocular and auditory abnormalities and other
autoimmune disorders.
Alphonse Corti (1831) was the first researcher to mention the presence of
pigment cells in the inner ear. There are many melanocytes in the human
cochlea, particularly in the modiolus, in the osseous spiral lamina, in Reissner's
membrane and in the vascular stria; melanocytes are found especially in highly
vascularized areas of apparently important secretory or metabolic function.
Although its exact role - and that of melanin - remains unknown, it is probable
that they have a vasomotor function in the inner ear. According to Savin (1965)
cells containing pigments are partially or fully adhered to blood vessel walls,
which are sites of intense metabolite exchanges.
Vitiligo is usually classified into localized, generalized, and universal types and is
based on the distribution in the body.
REVIEW OF LITERATURE
Carvalho (2004) found that otoacoustic emissions and the high frequency
sensitivity auditory function was affected negatively in patients with pigment
disorders, such as vitiligo. Huggins RH examined 50 patients with vitiligo and
auditory abnormalities were detected in 16% of cases. Nikiforidis studied 30
patients with active vitiligo and found a statistically significant (P < 0.01) decrease
of the peak I latency and increase of the I-III interpeak latency in the patients as
compared to the controls.
NEED OF STUDY
It has been reported earlier that vitiligo is predisposed with cochlear function.
Some of the preliminary reports have reported the involvement of high frequency
hearing loss, there is a need to explore the occurrence of hearing loss in these
patients. In the present study ABR and middle latency responses are also
conducted along with peripheral auditory lesion tests to find whether some
changes occur at brainstem or sub-cortical levels.
AIM
The present study aimed at evaluating the audiological status in patients with
vitiligo.
METHODOLOGY
The study was conducted in Speech and Hearing Unit, department of ENT,
PGIMER Chandigarh from December2009-July2010.The study group included
50 patients (25 Males, 25 Females) with vitiligo attending Department of
Dermatology in PGIMER. The age range varied from 11years to 50 years with
mean age of 27.4 years. Subjects with previous otologic disease, neurologic
disease, acoustic trauma, vascular disease, metabolic problems, ototoxic drugs
used in the past and middle ear problems were excluded from the study.
APPARATUS AND PROCEDURE
Detailed history was taken from the patient which included family history of
vitiligo, type, site and duration of pigmentary disease. After a physical
examination that included a complete Otorhinolaryngological examination,
detailed audiological investigation was done on all the patients by same
audiologist on same instruments. Audiological evaluation included:Pure tone Audiometry
High Frequency Audiometry
Otoacoustic Emissions including DPOAEs and TEOAEs
Tympanometry
Brainstem Evoked Response Audiometry
Middle Latency Responses
STATISTICAL ANALYSIS
Mean, standard deviation was computed for data description. Student's t test was
used to compare between two sample means. Results were considered
significant if p< 0.05.The data was divided into two groups. Group 1 comprised of
patients with localized vitiligo and group II consisted of patients with generalized
vitiligo. The data was also grouped according to duration and sex of the disease.
RESULTS
In extended high frequency audiometry, the mild 26% (13) and moderate
intensity hearing loss 28% (14) was most prevelant. The DPOAEs were absent in
24% (12) patients in right ear and 28% (14) in left ear. While TEOAEs were
absent in 56% (28) patients in right ear and 50% (25) patients in left ear.
When patients with Localized vitiligo (n=16) were compared with Generalized
Vitiligo(n=34), the SNR of TEOAEs was highly significant at 3 K Hz(t-2.06,p-0.04)
and 4K Hz (t-2.83,p-0.006) in left ear. The latency of wave Na in MLR was
significant between two groups (t-2.05,p-0.04).
The two groups, when compared on the basis of duration of vitiligo (group I-upto
60 months, group II-more than 60 months) ,high frequency audiometric
average(2,4 & 8 K Hz) was highly significant(t-3.37,p-0.001). The amplitude of
DPOAEs was significant between two groups at 499Hz (t-2.35,p-0.02).
DISCUSSION
We found that the prevelance of hearing loss was high at extended high
frequency among the patients with vitiligo with majority falling under moderatesevere hearing loss. Tosti et al. (1987) found hearing loss in 16% of subjects with
vitiligo; they raised the hypothesis that part of the melanocytes was injured by
auto-immunity due to vitiligo. A large number of our cases had absent OAEs
hence the present study strengthens the hypothesis that vitiligo is a significant
factor for altered cochlear function, and that melanin may in fact have an
important role in cell metabolism, facilitating substance exchanges and
maintaining endolymph, perilymph and ionic balance.
The pure tone average was higher in patients with long term vitiligo; (more than 6
months) at all frequencies. This finding signifies that the hearing thresholds
elevate when the vitiligo progresses. No relation was found between duration,
severity of the disease (number of affected sites) and any audiological
parameters in the study by Mamoun El-Sayed Shalaby.Thus our finding
contradicts the observations before.
The lost cochlear emission in vitiligo group has been explained previously by
Schrott A. and Spoendlin H. (1987). .They stated that hypopigmentation disorders
for a long duration may lead to degeneration of the outer hair cells beginning
from the basal turn of the cochlea while inner ear hair cells remain structurally
and functionally intact. Another explanation was related to endolymph Ca2+
levels, Gill S. and Salt A. (1997) found that in pigmented animals the endolymph
Ca2+ tended to increase from base to apex of the cochlea, while endocochlear
potential systematically decreased towards the apex.
Significant difference is observed in Na latency in both groups of Vitiligo which
signifies that in these patients some changes are taking place in sub-cortical
areas. These findings should be explored further.
CONCLUSION
Our results support possible auditory and electrophysiological changes in vitiligo
patients along with decreased cochlear function. The mechanism is most
probably multi factorial and may be related to individual susceptibility, residual
number of melanocytes in the inner ear and the nature of immunologic
abnormalities in patients with vitiligo. A larger multi center study of the higher
auditory function of vitiligo along the course of the disease is needed to prove the
role of vitiligo in hearing abnormalities.