Hereditary hearing loss of Carthage Monge family is a genetic disorder that affects many families in our country, most of the members reside in the province of Cartago, Taras, Quircot, El Molino and other neighborhoods, however, the author has records of several patients residing in other areas as Pavas or Guápiles. It is time that the national audiological community take corrective action in the treatment and rehabilitation of patients with this disorder, since technologies now allow better solutions to individuals suffering from this scourge.
Are records of hearing loss known as hereditary deafness Monge from about two centuries ago. By oral tradition known to doctors as the Carthaginians Dr. Jesús Guzmán studied this disorder since the early twentieth century. In 1977, researchers at the University of Costa Rica began the study and characterization of this hearing loss, these studies led to the construction of the first tree and connect with a common ancestor named Felix Monge, who was born in Carthage in 1740, apparently wealthy and prolific, stated in his will that he was deaf. In 1991, it was identified that the Monge family, genetic damage is located on the long arm of chromosome 5. Such damage was appointed by the International Commission of gene nomenclature as DFNA1 (DFN is an abbreviation of deafness word deafness in English and A1, which means prevail autosomal dominant gene). Today there are over 100 individuals carriers of this disorder [1-5].
Hearing loss of Monge, is a genetic disorder that is inherited from parents to children. It is autosomal dominant. Autonomy means that children of both sexes inherited no difference, ie it is not sex-linked. Dominant means that only one copy of the mutated gene altered or hearing loss occurs. Those affected have a copy of the mutated gene and an intact copy. This means that when an affected individual has children with a hearing individual can inherit mutated copy or copy intact. Children who inherit a mutated copy of the deaf parent have hearing loss at some point in life .
When an affected individual has children, there is a 50% chance of inheriting the mutated copy and 50% of that inherits the intact copy. If intact copy inherits the child will not conveylistener and hearing impairment. A mutated copy of the gene is sufficient to present the alteration as this hearing loss is dominant. No cases of hearing children hearing loss transmit to their offspring are known . The Monge-syndromic deafness is not because no known associated anomalies. The researchers propose that the mutation affects cytoskeletal repair of the sensory cells of the ear, including actin cilia of the hair cells of the organ of Corti within the cochlea. When these structures damaged, no gates which allow passage of salts (especially potassium) and this in turn causes the neuroelectric currents that carry information to the brain will not occur open .
Hearing tests conducted over the years from the baseline to allow today enumerate certain characteristics:
Sensorineural hearing loss
Starts in childhood, approximately between 4 and 6 years
Primarily affects the low frequencies and as it progresses, all frequencies in the audible range
The cochlear lesion
The post lingual hearing loss is
The use of hearing aids accelerates degeneration stereocilia cochlear hair cells.
Hearing tests performed by the author have demonstrated
that the use of headphones in one ear, causes the fastest on the
side adapted impairment, where that is a cause to contraindicate
its use, since not using prosthesis causes a deprivation finally
generates aural and auditory processing problem at the time that
the patient decides to use the prosthesis makes it very difficult
for this disorder. Another myth ruled today is the accelerated
evolution with pregnancies, as in monitoring pregnant carrier
has not demonstrated an evolution ng of deafness .
Note that to alleviate the devastating psychological,
sociological and physiological effects of hearing loss hereditara
is vital early identification of deafness Monge. This is easy to
achieve if they are made from childhood hearing tests to all
children of patients with hearing impairment. Unfortunately
today there is no program to monitor all families with members
carrying damage. The author suggests that in the early stages,
when the hearing loss is expressed with bilateral sensorineural
fall mild to moderate school use, this will improve the signal
to (Figure 1). Evolución audiométrica de la hipoacusia de la
familia Monge (Según Sánchez) noise ratio within the classroom
and will prevent the secondary auditory processing disorder
to poor discrimination in noise and lack of acoustic energy in
the perception of speech sounds. This would improve school
performance in children carrying early stage. Once actually
affect hearing loss frequencies of 1000 and 2000 Hertz, the
adaptive digital, programmable hearing aid with at least two
channels in order to handle the frequency disparity is proposed
To obviate the aesthetics alleged by the patients with hearing
loss, adaptation peritimpánico prosthesis type is suggested, as
long as the age and size of the external auditory canal permit.
When the patient reaches adulthood and hearing loss progresses
to profound hearing loss level, the performance of cochlear
implant technology available through social security, which replaces the function of the hair cells in the cochlea (where it has
proposed degeneration). Carriers of the Monge hearing loss, are
ideal candidates for this procedure because of their status have
acquired hearing loss after the acquisition of language.
The implementation of a rehabilitation program for patients
with Monge Deafness is essential in order to minimize the adverse
effects of this disorder, which are completely preventable by
timely identification. Institutions such as the University of Santa
Paula, the Costa Rican Social Security and distributors of hearing
aids have the responsibility to initiate a program of detection
and rehabilitation of hearing deafness due to Monge.
Meanwhile audiologists, otolaryngologists and students
observe impassively as compatriots uselessly sacrificed their
lives fighting a disability that can be rehabilitated, the problem
continues to advance and raising its cost to social, economic
and quality of life for individuals. The Monge have the right and
should have access to technology and surgical solutions that
represent auditory and cochlear implant prostheses to reduce
the negative effects of this disease.