Biomaterial Database

Improved turbidimetric assay for lysozyme in urine. 1983

M T Houser

I describe an improved turbidimetric assay for lysozyme in urine. This method is simple, reproducible, linear over a 100-fold concentration range, sensitive to concentrations as low as 10 micrograms/L, and only commercially available products are required. Evaluation of urinary lysozyme concentration with this assay demonstrated a within-run and between-run CV of 9.9% and 4.8%, respectively, for normal urine, minimal chemical interference, and a mean analytical recovery of 104.8%. There were differences in the rate of clearing and in the linearity of the assay with use of three commercial preparations of Micrococcus lysodeikticus, and significant differences in results when different lysozyme standards were used. Reference values were established by use of data on 169 healthy subjects, ages six months to 61 years. Clinical efficacy of the assay was demonstrated in children with renal disorders, especially those associated with chronic renal failure or tubular dysfunction.

UI	MeSH Term	Description	Entries
D007223	Infant	A child between 1 and 23 months of age.	Infants
D007674	Kidney Diseases	Pathological processes of the KIDNEY or its component tissues.	Disease, Kidney,Diseases, Kidney,Kidney Disease
D007676	Kidney Failure, Chronic	The end-stage of CHRONIC RENAL INSUFFICIENCY. It is characterized by the severe irreversible kidney damage (as measured by the level of PROTEINURIA) and the reduction in GLOMERULAR FILTRATION RATE to less than 15 ml per min (Kidney Foundation: Kidney Disease Outcome Quality Initiative, 2002). These patients generally require HEMODIALYSIS or KIDNEY TRANSPLANTATION.	ESRD,End-Stage Renal Disease,Renal Disease, End-Stage,Renal Failure, Chronic,Renal Failure, End-Stage,Chronic Kidney Failure,End-Stage Kidney Disease,Chronic Renal Failure,Disease, End-Stage Kidney,Disease, End-Stage Renal,End Stage Kidney Disease,End Stage Renal Disease,End-Stage Renal Failure,Kidney Disease, End-Stage,Renal Disease, End Stage,Renal Failure, End Stage
D008837	Micrococcus	A genus of gram-positive, spherical bacteria found in soils and fresh water, and frequently on the skin of man and other animals.
D008875	Middle Aged	An adult aged 45 - 64 years.	Middle Age
D009113	Muramidase	A basic enzyme that is present in saliva, tears, egg white, and many animal fluids. It functions as an antibacterial agent. The enzyme catalyzes the hydrolysis of 1,4-beta-linkages between N-acetylmuramic acid and N-acetyl-D-glucosamine residues in peptidoglycan and between N-acetyl-D-glucosamine residues in chitodextrin. EC 3.2.1.17.	Lysozyme,Leftose,N-Acetylmuramide Glycanhydrolase,Glycanhydrolase, N-Acetylmuramide,N Acetylmuramide Glycanhydrolase
D009391	Nephelometry and Turbidimetry	Chemical analysis based on the phenomenon whereby light, passing through a medium with dispersed particles of a different refractive index from that of the medium, is attenuated in intensity by scattering. In turbidimetry, the intensity of light transmitted through the medium, the unscattered light, is measured. In nephelometry, the intensity of the scattered light is measured, usually, but not necessarily, at right angles to the incident light beam.	Turbidimetry,Nephelometry,Turbidimetry and Nephelometry
D012016	Reference Values	The range or frequency distribution of a measurement in a population (of organisms, organs or things) that has not been selected for the presence of disease or abnormality.	Normal Range,Normal Values,Reference Ranges,Normal Ranges,Normal Value,Range, Normal,Range, Reference,Ranges, Normal,Ranges, Reference,Reference Range,Reference Value,Value, Normal,Value, Reference,Values, Normal,Values, Reference
D002648	Child	A person 6 to 12 years of age. An individual 2 to 5 years old is CHILD, PRESCHOOL.	Children
D002675	Child, Preschool	A child between the ages of 2 and 5.	Children, Preschool,Preschool Child,Preschool Children