Hyper and hypo glycemia

Normal ranges: There should be no glucose in the urine

Urinalysis tests

Glucose dipstick method

Specific for glucose

Uses glucose oxidase, which produces peroxide

Peroxide reacts with chromogen, catalyzed by peroxidase, to produce oxidized chromogen

The oxidized chromogen causes a color change

Sensitivity: 75-125 mg/dL

False positives: strong oxidizing agents and peroxides

False Negatives: ascorbic acid or improperly stored urine (glycolysis)

Clinitest

Uses copper reduction to detect any reducing substance

Copper sulfate is reduced to cuprous oxide

Sensitivity: 250 mg/dL

Specificity: all reducing substances

False positive: Any reducing substance, such as ascorbic acid

False negative: bleach or radiographic dye

Causes of glucosuria

1. Hyperglycemia exceeds renal threshold

2. Renal threshold is lower than normal, such as in renal glycosuria

Definition: glucose in the urine

Normal fasting plasma glucose: 70-99 mg/dL

High fasting plasma glucose: >126

Renal threshold: 160-180 mg/dL

Hyperglycemia: Increased glucose in the blood

Hypoglycemia: Low levels of glucose in the blood

Hyperglycemia

Diabetes Mellitus

Clinical findings

glycosuria

hyperglycemia

proteinuria

hypotonic urine

low urine specific gravity

ketonuria

electrolyte imbalance

Caused by insulin deficiency or resistance

Symptoms

polyuria

polydipsia

polyphasigia

microvascular damage

Diabetic nephropathy

Presents as a glomerular syndrome

Thickening of glomerular basement membrane

allows protein to leak through

Susceptible to pyelonephritis and papillary necrosis

Sequelae

Macrovascular damage

Hypoglycemia

Seen rarely, such as in cases of starvation