Deficiency of naive T cells in patients with sudden deafness.
BACKGROUND
Although there are a number of reports concerned with the role of immunity in the sudden onset of progressive sensorineural hearing loss, there are few references dealing with the involvement of immune-mediated mechanisms in sudden deafness.


OBJECTIVE
To study the phenotype of peripheral blood lymphocytes in a group of patients with sudden deafness by use of 3-color flow cytometry.


METHODS
The study was carried out prior to the start of steroid therapy. Fourteen patients underwent a follow-up study once steroid therapy had been completed. Prospective analysis, case-control.


METHODS
Tertiary case referral center, ambulatory and hospitalized care.


METHODS
Twenty-two patients (13 men and 9 women; mean age, 45.3 years) were compared with 14 healthy control subjects (9 men and 5 women; mean age, 36 years). Patients were divided in 2 groups according to their response to steroid therapy.


RESULTS
Decreased numbers of both CD4+ helper cells (38.4% vs 45.5%; P = .04) and CD8+ cytotoxic cells (17.5% vs 22.3%; P = .02) were observed in patients and compared with those in the control subjects, as well as reduced numbers of CD4+CD45RA+ cells (14.4% vs 29.3%; P = .01) and CD8+CD45RA+ naive cells (18.2% vs 25.4%; P = .04). In the group of patients with a good response to steroid therapy (group 1), a tendency toward normalization of the CD4+ (pretreatment, 38.6%; posttreatment, 44.6%), CD4+CD45RA+ (pretreatment, 15.2%; posttreatment, 21.7%), and CD4+CD45RO+ (pretreatment, 21.1%; posttreatment, 18.2%) cell counts was observed, with a slight decrease in the CD8+ population (pretreatment, 18%; posttreatment, 15.7%). However, in patients with a poorer response (group 2), while there were increases in the CD4+ (pretreatment, 38%, posttreatment, 50%) and CD4+CD45RA+ (pretreatment, 12.8%; posttreatment, 16.7%) cell counts after steroid therapy, there was a significant increment in the CD4+CD45RO+ memory cell count (pretreatment, 14.1%; posttreatment, 28.5%) and low CD8+CD45RA+ counts (pretreatment, 14.6%; posttreatment, 15.5%). No differences were observed in the numbers of B or natural killer cells or in the presence of activation antigens CD25 and HLA-DR when pretreatment and posttreatment levels were compared.


CONCLUSIONS
These results demonstrate significant abnormalities in the subpopulations of lymphocytes in patients with sudden hearing loss, suggesting the existence of immune-mediated responses in the inner ear as possible etiopathogenic factors in this entity.
García-Berrocal
J R
JR
Service of Otorhinolaryngology, Clínica Puerta de Hierro, Autónoma University, Madrid, Spain.
Vargas
J A
JA
Ramírez-Camacho
R A
RA
González
F M
FM
Gea-Banacloche
J C
JC
Vergara
J
J
Durántez
A
A
D000293:Adolescent; D000328:Adult; D001327:Autoimmune Diseases / Q000188:drug therapy / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000187:drug effects / Q000276:immunology*; D018414:CD8-Positive T-Lymphocytes / Q000187:drug effects / Q000276:immunology*; D016022:Case-Control Studies; D005260:Female; D005434:Flow Cytometry / Q000379:methods; D005938:Glucocorticoids / Q000627:therapeutic use; D003639:Hearing Loss, Sudden / Q000188:drug therapy / Q000276:immunology*; D006801:Humans; D007153:Immunologic Deficiency Syndromes / Q000188:drug therapy / Q000276:immunology*; D016130:Immunophenotyping; D017493:Leukocyte Common Antigens / Q000187:drug effects / Q000276:immunology; D008297:Male; D008775:Methylprednisolone / Q000627:therapeutic use; D008875:Middle Aged; D011446:Prospective Studies
D005938:Glucocorticoids; D017493:Leukocyte Common Antigens; D008775:Methylprednisolone