Basic Concepts in Clinical Biochemistry-A Practical Guide.7z

reacts with the chromogen to form a colored product. Sensitivity of the test is
0.01–1 g/dl.

GlucoseGOD!Gluconic acidþH 2 O 2

H 2 O 2!

POD

H 2 Oþ½OŠ

½OŠþotoluidine!coloured complex

13.5 Procedure

Strip is dipped in urine sample for 10 sec and color is observed after 30 min.
Compare the color formed with the chart provided.

11.4 Precautions

1. The container used for urine collection should be clean and free from
   contaminants, particularly disinfectants and detergents containing oxidizing
   substances such as peroxides.


2. Do not touch the test area of the strip.

11.5 Clinical Significance...............................

Reducing sugars are found only in very small amounts in the urine of normal
persons, usually less than 100 mg/day. Amount of sugars increases under some
pathological conditions that can be detected by various tests.

1. Glucose: Glucose is the reducing sugar found in urine which is pathologically
   significant. Normally less than 100 mg of glucose (sugar) is excreted per day.
   Glucose is present in urine whenever blood glucose rises above the renal thresh-
   old, i.e., 180 mg/dl blood. Excretion of glucose in urine is called glycosuria.
   Glycosuria is found in all conditions in which glucose tolerance is diminished.
   Persistent glycosuria may indicate diabetes mellitus. In diabetes mellitus, 5–6%
   glucose is excreted through urine of patient with endocrine hyperactivity. Severe
   liver disease and whole organ disease of the pancreas may also be accompanied
   by some glycosuria.


2. Lactose: It is found in the urine of lactating woman and toward the later stage of
   pregnancy.


3. Galactose: It is present in urine very rarely. It occurs occasionally in lactation.
   Galactosuria occurs in infants in recessive inherited disorder and is due to an
   inability to metabolize galactose derived from lactose in the milk.

11.5 Clinical Significance 51