68kD (hsp-70) antibodies by Line Blot

Category: Otology
Test Code: 340
Disease: Autoimmune Hearing Loss (SNHL)
Methodology: Line Immunoassay
Reference Range: Qualitative
CPT Code: 84182.
Schedule / Turnaround Time: Assay performed once per week. Report availability is within two weeks from the time of specimen receipt.
Specimen Requirements:

Specimen need not be refrigerated or frozen. Collect 2-3 ml of blood in a red top or serum separator tube. If possible, separate serum from clot and place into white tube provided with Immco Diagnostics’ collection kits. If separation facilities are not available, the blood can be sent in the tube used for collection.

Sample Stability:

Sample is stable at ambient temperature during shipment. If sample is stored prior to shipment, it is stable refrigerated (2-8˚C) up to five days and frozen (-20˚C or lower) up to one year.

Relevance:

Sensorineural hearing loss (SNHL), commonly referred to as nerve deafness, may be caused by genetic factors, acquired factors (i.e. infections) or can be immune mediated. In the majority of cases, no cause of SNHL is apparent. Such cases are referred to as idiopathic SNHL. A subgroup of idiopathic SNHL cases is treatable with immunosuppressive therapy. The laboratory studies used to identify these cases should include serum antibody tests to 68kD (hsp-70) inner ear antigen. 22% of patients with bilateral rapidly progressive SNHL have antibodies that react with the 68kD antigen. 68kD (hsp-70) antibodies also occur in approximately 60% of patients with bilateral Meniere's disease, 35% of patients with unilateral Meniere's disease and 37% of patients with contralateral delayed endolymphatic hydrops. In situations where corticosteroids are contraindicated, methotrexate or cytoxan treatment may be prescribed. Clinical Relevance: Sensorineural hearing loss (SNHL), commonly referred to as nerve deafness, may be caused by genetic factors, acquired factors (i.e. infections) or can be immune mediated. In the majority of cases, no cause of SNHL is apparent. Such cases are referred to as idiopathic SNHL. A subgroup of idiopathic SNHL cases is treatable with immunosuppressive therapy. The laboratory studies used to identify these cases should include serum antibody tests to 68kD (hsp-70) inner ear antigen. 22% of patients with bilateral rapidly progressive SNHL have antibodies that react with the 68kD antigen. 68kD (hsp-70) antibodies also occur in approximately 60% of patients with bilateral Meniere's disease, 35% of patients with unilateral Meniere's disease and 37% of patients with contralateral delayed endolymphatic hydrops. In situations where corticosteroids are contraindicated, methotrexate or cytoxan treatment may be prescribed.