Changes on blood filterability in patients with fluctuant

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Acta Otorrinolaringol Esp 2006; 57: 196-198
LETTER TO THE DIRECTOR
Changes on blood filterability in patients with
fluctuant hearing loss
F.J. García Callejo, C. de Paula Vernetta, E. Sebastián Gil, J. Marco Algarra
Servicio de ORL. Hospital Clínico Universitario. Universidad de Valencia. Valencia.
Abstract: We conducted a two-year follow-up of
thirteen subjects with fluctuating sensorineural hearing
loss, measuring their blood filterability (BF) and
correlating it to the onset of episodes of deafness. We
observed a decrease in the BF levels of all the patients
when they experienced hearing loss. When the patients
recovered their normal level of hearing, the BF also
increased. The use of reactive techniques to avoid these
decreases in BF could potentially prevent or correct
fluctuating deafness.
Key words: Blood filterability. Sensorineural hearing loss.
Erythrocytes.
Dear Director:
Perceptive hearing disorders have in the last decade
gone through an interesting advance in their diagnostic
orientation thanks to imaging and neurophysiological
tests. Recently, knowledge of immune mediated and
vasoactive phenomena and their implications for the
labyrinth has enabled measurements of peripheral
blood to be validated, offering physiopathological
reasons for using specific agents and treatment
procedures for types of hearing loss traditionally
considered irreversible. Among these the symptoms
defined within the context of autoimmune inner ear
disease and hearing loss developed as a result of blood
hyperviscosity stand out.
These laboratory tests have been well-studied in
cases of sudden deafness in which accessibility to the
patient is high, due to the symptoms being rapidly
identified and followed-up, as well as in cases of
degenerative and slowly progressive hearing loss, such
as presbyacusis, where the disorder proves to be
relatively predictable and, therefore, monitorable in the
patient.
Correspondence F. Javier García Callejo
C/ Luis Oliag n º 71 – 8
46006 Valencia
E-mail: [email protected]
Fecha de recepción: 27-9-2005
Fecha de aceptación: 6-3-2006
196
There are symptoms of a less clear etiopathogeny
whose chronobiology, being fluctuating, temporary,
repetitive, unpredictable and of rapid (if not sudden)
onset, disconcerts the specialist. The tonal audiometry
evaluation made during an episode of hearing loss is
characteristically sensorineural and cochlear. Treatment
is often empirical and includes corticotherapy,
hemorheotherapy vasodilators and anti-hemostatics,
sometimes in combination.
This fluctuating sensorineural hearing loss is well
defined as perceptive hearing loss, unilateral or
bilateral, - the latter kind can be either symmetrical or
asymmetrical, - and of relatively short evolution (weeks
or months). It is therefore possible to confirm a drop of
more than 10 dB HL at two or more consecutive tonal
frequencies over a two-month period in which a total or
partial recovery takes place, either spontaneously or
following treatment.
Between January 2001 and June 2005, 13 cases of
subjects who sought medical advice for FHL were
collected. With prior informed consent, the patients
underwent a Western-blot study with bovine antigenic
cochlear extract, which did not identify a band in any of
the cases. Furthermore, from the start of the study until
the end of the follow-up, the level of hearing was
monitored using pure-tone audiometry and peripheral
blood for the blood filterability capacity. This was
repeated every 2 months for 2 years, with every patient
consequently receiving thirteen check-ups.
The quantification of the degree of hearing loss
followed the specifications that conform to current
legislation in Spain1. The BF was calculated by
measuring the time it took for the volume of a column
containing 1 cc of whole anticoagulated blood to pass
through 5µ diameter polycarbonate filters at water
pressure of 20cc as per the Reid-Dormandy2 model. The
range of normality accepts a range of between 16.9 and
24.5 µ l/sec.
Figure 1 reflects the variation in the BF parameter
throughout the follow-up of the individual. Although
the average value in the group was 20.1±1.9 µl/sec, it
varied between 14.2 and 23.7 µl/sec. The fact that the BF
value was particularly low during the episodes of
temporary hearing loss detected in the pure-tone
audiometry as compared to the rest of the
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PERSISTENCE OF THE TIRAD BRANCHIAL ARCH
Figure 1. Recording of the evolution of blood filterability in ml/sec, (y axis), in the 13 measurements taken from each patient over the 2-year follow-up period,
(x axis in months), with ♦ indicating the period in which hearing loss or an increase in previously recorded hearing loss was detected.
measurements taken in the follow-up of each subject is
particularly noteworthy.
This group of individuals recorded an average of
1.9±0.7 FHL episodes over the 2-year period of the
study, which meant 129.6±52.8 days of hearing
alteration per patient. At the start of the study, the level
of hearing loss was 8.5±5.6%, with variations of between
0 and 0.9%. At the end of the study the average hearing
loss recorded was 11.4±8.2%, there being 4 patients
whose hearing improved, one whose hearing did not
change, and another 8 who experienced increases in
their hearing loss ranging from 8.5 to 67.23% of the
initial loss.
In the 36 audiometric recordings in which the
appearance or worsening of hearing loss was apparent,
the BF was 16.6±1.1 µl/sec, while in the rest of the
measurements taken (n=133) the BF had a value of 21.1
±1.1 µl/sec, a difference which proved to be statistically
significant (Students t test=22.342: p<0.0001). However,
when the 169 BF measurements were correlated with
the percentage of hearing loss detected, the resulting
straight line equation was y=18857x+48.218. This
revealed a non-statistically significant tendency
(R2=0.3071) to detect greater hearing losses when low BF
values are recorded.
The BF measurement copies in vitro the conditions of
blood flow in microcirculation. The filtration method
used generates a shear force over the blood of between
15 and 30 pascals, a similar value to that produced in
vivo in terminal and capillary arteries3. This is a
polyfactorial variable as the capacity for erythrocytic
deformity, leukocytosis and plasmatic factors such as
fibrogen, lipoproteins and immunoglobulins all bear an
influence4. Any variation in these parameters is
susceptible to reducing the BF and with it the debt that
accesses organs without vicarious circulation, such as
the labyrinth, which would explain the appearance of a
hearing disorder of rapid onset.
This drop in BF has previously been recorded in cases of
sudden deafness5,6, generally finding a prior trigger that
modifies the blood’s viscoelastic conditions, turning it
into a thicker liquid. However, the evolution of hearing
loss with a drop in BF does not necessarily appear to be
acute, as the drop coincided with the appearance of
197
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F. J. GARCÍA CALLEJO ET AL.
slowly progressive and definitive hearing loss in
physiopathological environments with a recognised
limitation over this parameter, such as hypertension,
diabetes mellitus or senility7-9.
The study of variations in the viscoelastic properties of
the blood in episodes of FHL had not previously been
documented. These results, although limited by the size
of the sample, justify treatment alternatives for this
hearing deterioration based on physiological reasons
such as the use of vasoactive agents, - pentoxifylline,
piracetam, naftidrofuryl, etc. or rheopheresis.
4.
5.
6.
7.
References
1.
2.
3.
198
Real Decreto 1971/1999,de 23 de Diciembre,de
Procedimiento para el Reconocimiento, Declaración y
Calificación del Grado de Minusvalía (BOE de 26 de enero
y 13 de marzo de 2000),Anexo 1A, Capítulo 13.
Reid HL, Barness AJ, Lock P. A simple method for
measuring erythrocyte deformability. J Clin Pathol
1976;29:855-861.
Lindmark K, Engstrom KG. Theoretical and experimental
aspects of erythrocyte filterability testing: flow acceleration
8.
9.
and systemic resistance. J Biomech 2002;35:683-688.
Evans SA, Adams R, Nash GB. What do measurements of
filterability of blood tell us about the effect of red cell
aggregation on flow resistance in small vessels?
Biorheology 1999;36:453-455.
García Callejo FJ, Martínez Beneyto MP, Platero Zamarreño A,
Marco Sanz M, Fernández Julián EN, Marco Algarra J. Estudio
no intrevencionista de las alteraciones de la filtrabilidad
sanguínea en el debut clínico de sorderas súbitas
neurosensoriales. Acta Otorrinolaringol Esp 2001;52:556-564.
Ciuffetti G, Scardazza A, Serafini G, Lombardini R,
Mannarino E, Simoncelli C.Whole-blood filterability in
sudden deafness. Laryngoscope 1991;101:65-67.
Gatehouse S, Lowe GD. Whole blood viscosity and red cell
filterability as factors in sensorineural hearing impairment
in the elderly. Acta Otolaryngol Suppl 1990;476:37-43.
García Callejo FJ, Orts Alborch MH, Morant Ventura A,
Marco Algarra J. Sordera súbita neurosensorial, síndrome
de hiperviscosidad sanguínea y diabetes mellitus. Acta
Otorrinolaringol Esp 2002;53:221-224.
García Callejo FJ, Laporta Marín P, de Paula Vernetta C,
Ramírez Sabio J, Montoro Santaelena MJ, Marco Algarra J.
Alteraciones en la viscosidad sanguínea en pacientes con
presbiacusia. Acta Otorrinolaringol Esp 2004;55:356-363.