Leukocyte esterase activity in effusion fluid of patients with otitis media.
Fluid obtained during myringotomy and tube placement in 20 patients with middle ear effusions was assayed for leukocyte esterase activity using a quantitative spectrophotometric assay. This quantitative assay used the synthetic substrate, N-tosyl indoxyl alaninate. Seven of the 20 samples showed no measurable enzyme activity (8 U/ml or less). The remaining samples demonstrated activity ranging from 20 to 1600 units. Although enzyme activity did not correlate well with the physical appearance of the fluid, it did correlate with clinical history, suggesting the presence of a purulent exudate rather than serous effusion. Leukocyte esterase activity in the fluid appears to hold promise as an indicator for the presence of chronic middle ear infection. The enzyme can be assayed by a simple and fast diagnostic strip test, with results available almost immediately.
Lebovics
R S
RS
National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD 20892.
Murthy
V V
VV
Karmen
A
A
D000293:Adolescent; D001769:Blood; D002265:Carboxylic Ester Hydrolases / Q000032:analysis* / Q000378:metabolism; D002648:Child; D002675:Child, Preschool; D002908:Chronic Disease; D004322:Drainage; D005122:Exudates and Transudates / Q000201:enzymology; D006314:Hearing Loss, Conductive / Q000201:enzymology / Q000601:surgery; D006801:Humans; D007223:Infant; D008876:Middle Ear Ventilation; D010034:Otitis Media with Effusion / Q000201:enzymology* / Q000473:pathology; D011446:Prospective Studies; D012008:Recurrence
C021443:leukocyte esterase; D002265:Carboxylic Ester Hydrolases