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EL-MINIA MED., BULL., VOL. 16, NO. 1, JAN., 2005
Mahmoud & Abdelsalam
__________________________________________________________________________________
EVALUATION OF AUDITORY FUNCTION IN CHILDREN
WITH CHRONIC RENAL FAILURE
By
Essam Aly Mahmoud*and Montaser Abdelsalam Hafez**
Departments of ENT and Audiology Unit,
*Assiut and **El-Menia Faculty of Medicine
ABSTRACT:
This study was conducted on 38 children with chronic renal failure all under
regular haemodialysis for more than two years. Twenty five normal healthy children
served as a control. They were subjected to clinical examination in the audilogy unit
in Assiut University Hospital. The examination included otoscopic examination, basic
audiological assessment, auditory brain stem response (ABR) and transient evoked
otoacoustic emission (TEOAE). Twenty patients had bilateral mild high frequency
sensorineural hearing loss (SNHL). Eight had bilateral moderate to severe SNHL and
ten had normal hearing threshold . All are subjected to examination 1-2 days before
dialysis session. TEOAE and ABR test was carried out for those whose ears has
normal hearing threshold . No response in TEOAE (fail) was obtained in 10% of them
but none of the control and a partial pass response in 40% versus 10% of the controls
(P< 0.001). The mean overall echo-level and reproducibility were significantly lower
in patients than in the controls. The overall echo-levels did not correlate with serum
urea, creatinine, serum sodium or potassium and also for ABR results. The ABR
results showed significantly elongated III, V peak latencies as well as I-III and I-V
interpeak latencies compared to the controls. Cochlear dysfunction was mainly at low
frequency band. The changes in the ABR reflect sub clinical disturbances in neural
conduction of auditory pathway.
KEYWORDS:
Chronic renal failure
Emissions
Audiometry
ABR.
INTRODUCTION:
Sensorineural hearing loss occurs
in as many as 40% of long term
hemodialysis patients with chronic
renal failure. Before the advent of
haemodialysis and renal transplanttation, uremia patients apparently had
no higher incidence of hearing or
vestibular loss than the general population. Such problems have been attributed to ototoxic medications, electrolyte imbalance, inadequate dialysis or
disease or unknown cause (Bergstrom
et al., 1980).
Otoacoustic
Gatland et al., (1991) studied the
prevalence of sensorineural hearing
loss in patients with chronic renal
failure and threshold changes following haemodialysis. They found incidence of hearing loss is 41% in the low,
15% in the middle and 53% in the high
frequency ranges respectively. They
found no correlations between weight
changes, haematocric, metabolic bone
disease or ototoxic drug history of the
patients and changes in hearing threshold level.
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Mahmoud & Abdelsalam
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Bazzi et al., (1995) studied the
effect of short term and long term
haemodialysis on hearing in patient
with chronic renal failure. They found
incidence of 61.5% sensorineural
hearing loss. There was no correlation
between hearing loss and plasma
creatinine. Patients with plasma urea
>200 mg/dL had higher percentage of
hearing loss (86%) than with plasma
urea <200 mg/dL (69%). They
concluded that hearing loss in children
with chronic renal failure was mainly
cochlear SNHL.
of integrity of the central auditory
system is the auditory brain stem
response (ABR). ABR yields valuable
information about the impulse conduction along the brain stem pathway.
Thus, it could be useful in the investtigation of the neuro-otological dysfunction associated with renal failure.
Fan et al., (1994) measured brain
stem auditory evoked potentials
(BAEP) in 20 chronic renal failure
patients. They found marked increase
in wave I, III, V peak latencies and IIII, I-V interpeak latencies and no
correlation between plasma protein,
hemoglobin, urea, creatinine, serum
electrolytes and BAEP measurements.
They realized that BAEP could be used
as objective index in deciding the inner
ear and nervous system damage in
chronic renal failure.
Nikolopoulos et al., (1997)
investigate hearing acuity in young
children suffering from renal insufficiency. They reported that SNHL
(mainly high-frequency) of unknown
cause was found in 30.4% and hearing
loss was not influenced by various
haematological,
biochemical
and
clinical parameters as blood pressure
and history of ototoxic drug administration. However, hearing loss seemed
to be affected by the method of
management of the renal insufficiency
(more in the haemodialysis group than
in the peritoneal dialysis).
Katedra et al., (2002) investigate
the effects of haemodialysis in children
at the terminal phase of chronic renal
failure (CRF) as a potential factor
responsible for SNHL. They examined
20 child with (CRF) before and after
dialysis using pure tone audiometry,
brain stem evoked potentials (BAEP)
and acoustic otoemissions (TEOAE
and DPOAE). They found significant
SNHL, significantly elongated I, III, V
peak latencies as well as I-III and I-V
interpeak latencies in BAEP of
children with CRF and DPOAE was
improved after dialysis in range of
frequencies which was absent before.
They concluded that ABR and OAEs
could reflects the influence of electrolyte disturbances associated with CRF
on auditory function.
Mancini et al., (1996) investgitated the incidence of SNHL in 68
patients who reached chronic renal
failure (CRF) in childhood with aim of
identifying possible risk factors. They
reported 29% SNHL in patients under
conservative treatment, 28% of patients
on hemodialysis, and 47% after renal
transplantation. Also they found a
significant correlation with the administration of ototoxic drugs.
The clinical utilization of electrophysiological activities of the auditory
system has opened a new era in the
ability to diagnose central auditory
impairment. The most utilized electrophysiological technique for evaluation
Samir et al., (1998) investigate
the effects of chronic renal failure in
children using transient otoacoustic
emission test (TEOAE). They reported
cochlear dysfunction at low frequency
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EL-MINIA MED., BULL., VOL. 16, NO. 1, JAN., 2005
Mahmoud & Abdelsalam
__________________________________________________________________________________
bands as detected by TEOAE results
and that the overall echo-levels of
TEOAEs did not correlate with serum
urea, creatinine, sodium or potassium.
methods for evaluation of auditory
function.
MATERIALS AND METHODS:
Materials:
Study group: n= 38
The group consisted of 38 children suffering from chronic renal
failure and undergoing haemmodialysis
in the pediatric unit for renal failure for
more than two years. Their age ranged
between 10 and 18 years old and sex
distribution was (10 female and 28
male).
Hurks et al., (1995) studied
auditory brain stem (ABR) and
somatosensory
evoked
potentials
(SSEP) in children with chronic renal
failure. They reported a delay in peak I
latency of ABR which is an indication
for peripheral conduction dysfunction.
There was no differences between the
children treated conservatively and
those with continuous peritoneal
dialysis.
Control group: n= 25
Consisted of 25 normal healthy
children from those attending the
audiology unit with their family. Their
age and sex distribution matched those
of the study group.
Stanvroulaki et al., (2001)
studied the effect of chronic renal
failure on hearing organ in young
patients using distortion product otoacoustic emissions. They found signifycantly lower amplitudes of DPOAE in
all frequencies >1184 even in patients
with normal pure tone thresholds. They
reported that DPOAE seem to be more
sensitive to incipient cochlear damage
than behavioral threshold in monitoring renal patients.
Criteria for selection of the study
group:
- The study group had the criteria of
chronic renal failure as the following :
Clinical manifestations as :
Pallor (anemia), polyurea, polydipsia,
edema,
hypertension,
vomiting.
(Bergstein , 2000) .
- Laboratory abnormalities including :
Anemia,
leukopenia,
thrombocytopenia,
hyperkalemia,
hyponatremia
And elevated serum urea and creatinin
level .
- The normal of blood chemistry in
normal child age (10-18) was :
Serum urea (3.0-5.7) m mol/L
Serum creatinine (0.3-0.7)m mol/L
Serum sodium (138-145) m mol/L
Serum potassium(3.5-6.0) m mol/L
(Nelson,2000) .
- No history of ear disease or other
systemic diseases that cause hearing
loss.
- Normal otoscopic examination.
-Normal blood pressure and heart
examination.
This study was designed to
explore the effects of chronic renal
failure on hearing function of young
children and the use of otoacoustic
emission tests and evoked auditory
potentials as auditory brain stem
response (ABR) as an objective tests to
investigate the disturbances in this
function.
AIM OF THE WORK:
1- The aim of this study was to clarify
the effect of chronic renal failure in
children on the cochlea and central
auditory pathway specially on the brain
stem level and to determine the degree
of hearing loss if present.
2- To evaluate the sensitivity of
TEOAE and ABR tests as objective
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EL-MINIA MED., BULL., VOL. 16, NO. 1, JAN., 2005
Mahmoud & Abdelsalam
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B- Methods:
The children for the study group
were examined once between the
dialysis sessions i.e. 1-2 days before
the dialysis session.
All subjects of the study and
control group were subjected to the
following:
- ENT examination.
- Pure tone audiometry (PTA): at active
intervals from 250 Hz to 8000 Hz for
air conduction and 500 Hz to 4000 Hz
for bone conduction.
Normal hearing threshold (0-25 dB HTL)
Mild hearing loss (26-45 dB HL )
Moderate hearing loss (46-70 dBHL )
Severe
hearing
loss
(71-90
dBHL).(Katz ,1990 )
- Auditory brain stem response (ABR):
was performed monaurally using
alternating dick at 90 dBnHL intensity
level with repetition rate 21:1
puls/second. The absolute latency and
interpeak latency value of each tracing
was obtained and saved for further
analysis.
In this study the results were interpreted
according to Maxon et al., ,1993 .
A response was considered present
whenever their was an emission 3dB
signal/ noise ratio or above (i.e. 3 dB
above noise floor) in any frequency
band .
According to this classification, the
results of TEOAE were interpreted into
one of the three categories.
Pass: the response was 3 dB or above in
each of the tested frequency bands
(1,2,3, and 4 K Hz ) .
Partial pass: The response was present
in at least one of the tested frequency
bands.
Fail: no cochlear response was present
at any of the tested frequency bands.
For both ABR and TEOAEs the
comparison between both study and
control groups were done only for
children with normal hearing threshold.
- Statistical analysis was performed
using t-student test to compare between
the study and control group.
- The study group children were
diagnosed clinically as chronic renal
failure and all fulfilled the criteria for
renal failure as the laboratory finding
for each child were estimated.
The following ABR parameters were
applied:
Click duration: 100 ms
Number of sweeps: 2000
Delay: zero
Gain: 100 k
Low pass frequency: 100 Hz
High pass frequency: 3k
Sweep time: 12 ms
Electrode placement: active on the
vertex, reference on the mastoid of the
test ear and ground electrode on the
other mastoid.
- Transient evoked otoacoustic emission
(TEOAE): Using a stimulus non-linear
click of 80 micro second duration.
The intensity was adjusted to be
approximately 85 dBspl .
TEOAE were analyzed during the 20
ms after the stimulus and a total of 26
average on each two buffers (A & B)
were stored fore analysis .
RESULTS
Study group:
This group consisted of 38
children with CRE. The results of the
study group showed significantly high
frequency SNHL ranged from mild to
moderately severe.
There were 20 child has bilateral
mild high frequency SNHL, eight had
bilateral moderate to severe SNHL and
ten children had bilateral normal
hearing threshold.
Table (1) showed a statistically
significant increase in hearing threshold level at frequencies 2, 4, 8 KHz
when compared to control group.
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EL-MINIA MED., BULL., VOL. 16, NO. 1, JAN., 2005
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__________________________________________________________________________________
Table (1): Comparison of the mean (X) and SD of the study and control groups for
average pure tone hearing thresholds of both right and left ears.
Frequency
250
500
1000
2000
4000
8000
Study group
Mean
SD
15
4.08
20
5.41
25
3.90
35
6.12
50
6.19
65
3.15
Control group
Mean
SD
15
4.05
22
3.21
24
5.10
23
0.34
25
2.56
25
3.41
Results of transient evoked otoacoustic emission:
TEOAE was done only for 10 children
of the study group, those having
normal hearing threshold. Table (2)
showed that these was no response in
TEOAE (fail) in 10% of the study
group but none of the control group
and 40% partial response versus 10%
Significance
P
0.32
0.21
0.25
< 0.001*
< 0.001*
< 0.001*
of the controls (P< 0.001). The results
of TEOAE overall response and
reproducibility were significantly lower
in the study group when compared to
the control group (Tables 2 and 3). The
lower frequencies of reproducibility
were mainly affected
Table (2): The percentage of each category of TEOAE in the study and control groups
Category
Pass
Partial pass
Fail
Total
Study group
No.
5
4
1
10
Control group
%
50%
40%
10%
100%
No.
9
1
zero
10
%
90%
10%
0%
100%
Table (3): Comparison of TEOAE overall response level, repro ducibility % and
reproducibility at each frequency band in the control and study groups.
TEOAEs
Study group
Mean
SD
Response
7.57
4.16
Whole repro %
66.2
13.4
0.5 KHz
70.4
11.4
1 KHz
60.3
21.2
2 KHz
87.5
16.1
3 KHz
90.5
22.1
4 KHz
75.3
26.2
P< 0.05 significant
Control group
Significance
Mean
SD
P
19.5
4.51
0.001**
96.7
5.32
0.006**
90.5
16.11
0.04*
80.5
12.4
0.01*
90.7
17.3
0.34
95.3
22.4
0.21
75.2
18.4
0.35
P< 0.001 highly significant
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__________________________________________________________________________________
Results of auditory brain stem
response testing:
The results of ABR in the study
group were compared only for children
with normal hearing threshold . They
showed significant delay in the latency
of wave III and V, also the interpeak
latencies
I-III and
I-V
were
significantly delayed when compared
to the control group at intensity level
90 dBnHL with RR 21.2. This was
shown in Tables from (4) to (7).
Table (4): Comparison of the ABR wave latency mean and SD in the control and
study groups at 90 dBnHL and RR 21.1 for the right ear.
Wave
I
III
V
Study group
Mean
SD
1.55
0.31
4.11
0.25
6.21
0.14
Control group
Mean
SD
1.41
0.21
3.51
0.22
5.72
0.31
Significance
P
0.13
0.001**
0.001**
Table (5): Comparison of the ABR wave latency mean and SD in the control and
study groups at 90 dBnHL and RR 21.1 for the left ear.
Wave
I
III
V
Study group
Mean
SD
1.59
0.25
4.25
0.31
6.12
0.51
Control group
Mean
SD
1.32
0.41
3.62
0.14
5.82
0.21
Significance
P
0.23
0.001**
0.001**
Table (6): Comparison of the ABR interpeak latency mean and SD in the control and
study groups at 90 dBnHL and RR 21.1 for the right ear.
Interpeak
Latency
I – III
I–V
Study group
Mean
SD
2.56
0.25
4.66
0.41
Control group
Mean
SD
2.12
0.31
4.21
0.25
Significance
P
0.01*
0.02*
Table (7): Comparison of the ABR interpeak latency mean and SD in the control and
study groups at 90 dBnHL and RR 21.1 for the left ear.
Interpeak
Latency
I – III
I–V
Study group
Mean
SD
2.66
0.42
4.35
0.43
Control group
Mean
SD
2.13
0.11
4.12
0.22
244
Significance
P
0.05*
0.04*
EL-MINIA MED., BULL., VOL. 16, NO. 1, JAN., 2005
Mahmoud & Abdelsalam
__________________________________________________________________________________
Table (8): Results of correlation coefficient (r) between different audiological
parameters and biochemical values measured in the study group .
Audiological
parameters
PTA threshold
Average
ABR latency
For wave V
ABR interpeak
I-V .
OAE response
In dBspL
Biochemical
Measures
Na
Potassium
Blood urea
Creatinine
Na
Potassium
Blood urea
Creatinen
Na
Potassium
Blood urea
Creatinine
Na
Potassium
Blood urea
Correlation ( r )
Significance
- 0.1917536
0.9913458
-0.3458893
0.6778321
-0.155978
0.1145887
-0.8765127
-0.9845332
0.9112456
0.9983564
-0.8755214
-0.9665231
0.9953126
0.1332876
-0.3466794
Insignificant
Insignificant
Insignificant
Insignificant
Insignificant
Insignificant
Insignificant
Insignificant
Insignificant
Insignificant
Insignificant
Insignificant
Insignificant
Insignificant
Insignificant
No correlations were found between the serum urea, creatinine, sodium or
potassium and PTA, TEOAE or ABR findings.
DISCUSSION:
In this study their were
statistically significant
difference
between the study and control group in
pure tone threshold. There were 20
child has bilateral mild high frequency
SNHL, eight had moderate to severe
and ten had normal hearing threshold
level as shown in Table (1). Hearing
loss mainly sensorineural type, involving high frequencies 2, 4 and 8 KHz.
There were no correlation between
hearing threshold level and other
factors as blood urea, creatinine or
sodium and potassium serum levels.
correlated to the duration of dialysis
and duration of illness, but single
session dialysis appears to had no
effect on hearing organ. Also
Nikolopoulous et al., (1997) agreed
with the results of this study. They
investigated hearing acuity in young
children and reported mainly high
frequency SNHL which is not correlated to various haemological, biochemical and other clinical parameters.
Mancini et al., (1996) agreed
with the results of this study. They
investigate the incidence of SNHL in
young children with chronic end stage
renal failure. They reported incidence
of 29% SNHL in patients with conservative treatment, 28% of patients on
haemodialysis and 47% after renal
transplantation.
These results agreed with results
of many studies including Bergstrom et
al., (1980), Gatland et al., (1991) and
Bazzi et al., (1995); they reported high
frequency SNHL in patients with
chronic renal failure after dialysis and
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EL-MINIA MED., BULL., VOL. 16, NO. 1, JAN., 2005
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The results of TEOAEs test
showed statistically significant decrease in overall response amplitude and
at low frequency bands below 2 KHz
(Table 3). These results agreed with the
studies on otoacoustic emissions by
Katedra et al., (2002) and Samir et al.,
(1998). They investigated the effect of
electrolyte disturbances in children
with chronic renal failure on hearing
function using EOAEs test to investtigate cochlear function. They reported
significant decrease in the amplitude of
TEOAE and DPOE in children due to
chronic renal failure and that long term
dialysis (duration of dialysis) was
correlated to the effects on cochlear
function.
Ozturan et al., (1998) agreed
with the results of this study. They
used audiometry and DPOAE to
investigate the effects of chronic renal
failure on hearing. They reported high
frequency SNHL, but the acute effect
of dialysis has no direct effect on
hearing threshold level.
Also Gierek et al., (2002) used
electrophysiological examinations as
(ABR and DPOAE) to test hearing
organs in patients under haemodialysis
suffering from chronic renal failure.
Their results agreed with the results of
this study. They concluded that the
latency of ABR waves I, III, V and
interpeak latency I-V were significantly
elongated and DPOAE amplitude also
was significantly decrease in patients
with chronic renal failure under dialysis for a period of sex months.
The results of auditory brain
stem response testing showed signifycantly elongated III, V peak latencies
as well as I-III and I-V interpeak
latencies when compared to the control
group. This indicating that chronic
renal failure not only affects cochlear
function but also results in delayed
neural conduction in the brain stem.
From this study it was apparent
that chronic renal failure in children
under regular haemodialysis could
results in diminution of hearing affecting mainly high frequency region
from 3-8 KHz and both cochlear and
brain stem function are affected most
probably due to electrolyte disturbances and its effects on cochlear
function and nerve conduction along
the brain stem. This could be elicited
by the changes in ABR findings and
TEOAEs test results in this study.
These results agreed with the
results obtained by Fan et al., (1994)
and Kalcolra et al., (2002). They used
evoked potential testing as a tool for
investigating auditory pathway and
they found that chronic renal failure in
_hildren leads to significant elongation
in wave I, III, V peak latencies and IIII, I-V interpeak latency values and
their were no correlations between
these findings and plasma protein
levels or haemoglobin, urea, creatinine
and serum electrolytes. All these
results also agreed with the results of
this study in which no correlation also
were
found
between
TEOAE
amplitude decrease or ABR values and
that of serum urea, creatinine or
sodium and potassium serum levels.
CONCLUSIONS:
- Chronic renal failure in children under
regular haemodialysis results in mild to
moderately severe SNHL affecting
mainly high frequency region at 3-8
KHz.
- Auditory function in children with
chronic renal failure was affected at the
levels of both cochlea and brain stem
and otoacoustic emission, ABR testing
could be used as objective tests for
evaluation of these changes.
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‫‪EL-MINIA MED., BULL., VOL. 16, NO. 1, JAN., 2005‬‬
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‫__________________________________________________________________________________‬
‫دراسة حالة السمع عند األطفال اللذين يعانون من الفشل الكلوى المزمن‬
‫عصام الدين على محمود* ‪ -‬منتصر عبد السالم حافظ**‬
‫قسم األنف واألذن والحنجرة (وحدة السمعيات) ‪-‬‬
‫كلية طب *أسيوط و**المنيا‬
‫وأجريت هذه الدراسة على عددد ‪ 83‬طفدل يعدانون مدن فشدل كلدوى مدزعمن ويعالجـدـون بواسدطة‬
‫االستصفاء الدموى المتكرر لمدة تزيد عن عامين‪ .‬تم إختيار مجموعة حكم مكونة من ‪ 02‬طفدال‬
‫طبيعيا‪.‬‬
‫طريقة البحث‪:‬‬
‫خضعت مجموعة الدراسة ومجموعة الحكم إلى الفحص اإلكلينيكى الكامل وفحص األنف‬
‫واألذن والحنجددرة وقيدداس السددمع التقليدددى وكددذلث قيدداس البددث الصددوتى المةددار لدد ذن الداخليددة‬
‫وقياس الجهد المةار لجذع المخ‪.‬‬
‫وجددد أن األطفددال المصددا بون بالفشددل الكلددوى يعددانون مددن ضددعف سددمعى حسددى عصددبى‬
‫متوسط أو شديد فى الترددات العالية فقط‪.‬‬
‫تم إجراء الفحوصات السابقة على األطفال قبل إجراء الغسيل الكلوى بيوم أو يومين حتى‬
‫ال يدخل تأةير الغسيل فى نتاعج البحث‪.‬‬
‫وجد أيضا أن البث الصوتى ل ذن أقدل مدن الطبيعدى وكدذلث بالنسدبة لقيداس الجهدد المةدار‬
‫لجذع المخ وجد تأةير واضح فدى درجدة توصديل اإلشدارات عدن طريدا جدذع المدخ عندد مقارندة‬
‫النتاعج لمجموعة الحكم‪.‬‬
‫ةبت مدن هدذه الدراسدة أن الفشدل الكلدوى المدزمن عندد األطفدال يدعدى إلدى ضدعف سدمعى‬
‫حسى عصبى متوسط أو شديد فى الترددات العالية وكذلث يمكن إستنتاج أن هذا التأةير ناتج عن‬
‫إصابة األذن الداخلية وتوصديل اإلشدارات عدن طريدا جدذع المدخ وذلدث كمدا يتضدح مدن التدأةير‬
‫على قياس البث الصوتى وقياس الجهد المةار لجذع المخ‪.‬‬
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