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As printed in Hearing Health, volume 20:2,
Summer 2004
Every nation has unique socio-cultural, environmental
and medical factors creating specific challenges to
achieving hearing health. Some are nearly catastrophic.
Epidemic diseases in India and South Africa are wreaking
havoc on hearing, affecting their people now and far
into the future. Other challenges reflect poverty and
lack of infrastructure in the aftermath of war. Cambodia
is so impoverished that it lacks funds to educate its
deaf citizens, leaving them with few opportunities to
succeed. Due to these crises and countless more, the
need grows more pressing daily among the world’s
millions with hearing loss for information, services
and technology.
Responses to today’s barriers to better
hearing are emerging from a variety of dedicated people
and programs. We believe that the authors of the profiles
below contribute a clearer understanding of existing
crises and an awareness of the
diligence of those who rise to meet them.
By D. E. Lubbe, M.B. Ch.B., FCORL (SA)
Today, 8,000 people will die of AIDS. The numbers are
numbing as we struggle to comprehend the most critical
health concern currently facing the world. This is especially
true in Africa, now bearing the brunt of this modern-day
plague. Seventy percent of all AIDS victims live in
Sub-Saharan Africa.
More than 30 percent of people ages 15 to 49 have AIDS
in Botswana, Zimbabwe, Swaziland and Lesotho. In South
Africa, an estimated 5.3 million of the 44.7 million
total inhabitants live with the human immunodeficiency
virus (HIV). The virus has reduced life expectancy in
this nation to 43 years for women and 45 years for men
and threatens further corrosion of the burdened national
healthcare program.
Though hardly as critical as the deadly disease itself,
the hearing health of many South Africans has been greatly
impacted by AIDS-related hearing disorders. While managing
AIDS symptoms, they must also deal with unabated and
unaided hearing
conditions, further degrading their quality of life,
because treatment is so hard to obtain.
South African healthcare consists of a small private
sector and a state sector that attempts to care for
82 percent of the population. The under-resourced, under-funded
state program faces a huge task to provide healthcare
to the impoverished majority.
The system consists of three levels. Primary care centers,
run mainly by nursing staffs and junior medical officers,
refer patients to secondary tier hospitals, where most
uncomplicated surgeries are performed, and to tertiary
care hospitals. Only the tertiary level provides access
to ear, nose and throat (ENT) specialists and audiology
services. These centers are therefore beleaguered by
people who could be managed at primary or secondary
levels for hearing tests and corrective treatment.
HIV’s Impact
HIV-positive patients have an increased incidence of
both conductive and sensorineural hearing loss. Sensorineural
losses result from damage of either the cochlea or the
cochlear nerve. Common infections responsible for this
type of deafness in the HIV population and seen frequently
in South Africa are cryptococcal meningitis, tuberculous
meningitis, tertiary syphilis and longstanding untreated
middle ear disease that results in bacteria spreading
to the inner ear structures. HIV itself is a virus that
affects neural structures and can also cause a sensorineural
loss.
Conductive hearing loss is caused by an abnormality
affecting the ear canal, eardrum or middle ear. Accumulation
of fluid in the middle ear cavity (effusion) is common
in HIV-positive patients and can cause significant hearing
loss. One of the main reasons for fluid buildup is obstruction
of the eustachian tube by a mass of lymphoid tissue
that forms in response to infection with HIV.
Inserting a tube in the eardrum allows ventilation
of the middle ear and hearing rapidly returns to normal
but use of this treatment for HIV-positive individuals
has been controversial. A major concern is the risk
of the patient developing a middle ear infection as
a result of the insertion procedure, further compromising
hearing. Research currently underway at our institution
does not suggest that an increased risk exists, however.
Ventilation tube insertion is minimally invasive, cost
effective and can be performed on an outpatient basis.
Chronic suppurative otitis media (CSOM) implies a chronically
discharging ear due to an infected middle ear cavity
and a perforated eardrum. CSOM is a common disorder,
especially in children with HIV. Initially, it can be
managed with topical antibiotic eardrops and regular
cleaning of the ear. Surgery is an option for patients
with a persistently discharging ear that is not responding
to medical therapy.
Due to a limited health budget, only tertiary care
centers have access to topical antibiotic eardrops.
Primary care clinics and hospitals can only prescribe
cleaning of the ears and diluted vinegar drops to CSOM
patients, in some cases for years. Very few patients
are eventually referred to a tertiary institution and
assessed by an audiologist or ENT surgeon and by then,
a large number have a significant irreversible hearing
loss.
AIDS and Tuberculosis
There are approximately 2 million tuberculosis (TB)
cases per year in Sub-Saharan Africa and this number
is on the rise due to the devastating effect of the
HIV/TB disease combination. Infection with both HIV
and TB leads to a rapid progression of both diseases.
Although one-third of the world’s population
is currently infected with TB, only 5-10 percent of
infected people will become sick during their lives.
This usually occurs when the body’s immune system
is weakened. Infection with HIV drastically weakens
the immune system and leads to activation of the dormant
TB organism.
In Southern Africa, the combination of these two infections
is further complicated by the rise of multi-drug-resistance
TB (MDR-TB), a devastating form that results when TB
patients stop taking their medication, usually because
they start feeling better. The TB organism becomes resistant
to the prescribed medication and the disease can become
unresponsive to future treatment. This has resulted
in a huge population of HIV-infected individuals who
are being treated for TB for the second or third time.
The combination of MDR-TB and HIV is lethal and these
patients need drastic treatment measures to cure them
and also to prevent the spread of this deadly form of
TB.
A popular form of treatment for MDR-TB with HIV is
intramuscular injections of streptomycin, a known ototoxin,
meaning it has the potential to cause irreversible damage
to the inner ear structures and result in deafness and
balance problems. Thus, this life-saving measure for
MDR-TB with HIV often has the unfortunate consequence
of permanent hearing impairment.
Obstacles to Treatment
Detected early enough, any of the disorders mentioned
above can be treated and hearing can be preserved. However,
the structure of state healthcare in South Africa has
impeded the early identification and treatment of HIV-related
hearing disorders.
Other factors come into play as well. HIV-positive
patients in South Africa frequently do not complain
of deafness until significant hearing loss has occurred.
They usually have many symptoms and initially may perceive
hearing loss as a relatively minor problem in comparison.
According to a recent survey of HIV-positive patients,
a large proportion of those experiencing hearing loss
thought that this was part of the disease process and
did not mention it to the attending physician.
Finally, the majority of HIV-infected individuals are
treated at primary care facilities, again where there
is no provision for hearing tests or treatment. A study
is currently underway to try to identify HIV-positive
patients at the primary care level who have ear disorders.
The purpose is to determine how prevalent hearing loss
really is in this population.
Not only does a small percentage of HIV-positive patients
with hearing problems reach the tertiary center, even
fewer are candidates for hearing amplification although
many of them would benefit from a hearing aid. Due to
limited availability in South Africa, however, only
young patients with significant bilateral loss or those
who can afford to contribute financially to the hearing
aid purchase are offered this treatment option.
Of highest priority in this AIDS crisis is the acquisition
and distribution of Highly Active Anti-Retroviral Therapy,
the medicine that can prolong the life of people with
HIV. The rampant hearing loss of HIV-positive patients
receives scant attention in comparison. Nevertheless,
increased funding aimed at generally improving the primary
and secondary healthcare systems in South Africa could
result in more effective methods for identifying hearing
disorders early enough to provide treatment and prevent
the permanent, debilitating hearing loss with which
so many AIDS survivors will be left.
Dr. Darlene Lubbe is a practicing
physician specializing in ear, nose and throat medicine
at Groote Schuur Hospital in Cape Town. She can be contacted
at Division of Otorhinolaryngology, H-53 Old Main Building,
Groote Schuur Hospital, Observatory, Cape Town, South
Africa, or by emailing: delubbe@kingsley.co.za.
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Rubella Deafens
India
Breaking the Silence
in Cambodia
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