¾ Audit compliant ¾ Pregnancy test capability using the NEW CIinitest hCG ¾ Automation reduces the risk of errors. A Wide Range of Test Parameters Clinitek status is suitable for use with a wide range of

 

Urobilinogen

The normal urobilinogen range obtained with this test

is 0.2 to 1.0 mg/dL. A result of 2.0 mg/dL represents the

transition from normal to abnormal, and the patient and/

or urine specimen should be evaluated further.

Specific Performance Characteristics

Specific performance characteristics are based on clinical

and analytical studies. In clinical specimens, the sensitivity

depends upon several factors: the variability of color

perception, the presence or absence of inhibitory factors

typically found in urine, the specific gravity, and the pH

(see Limitations of Procedures section); and the lighting

conditions when the product is read visually. Because

the color of each reagent area changes as the analyte

concentration increases, the percentage of specimens

detected as positive will increase with the analyte

concentration.

Each color block or instrumental display value

represents a range of values. Because of specimen and

reading variability/specimens with analyte concentrations

that fall between nominal levels may give results at either

level. Results at levels greater than the second positive level

for the glucose, ketone, protein and urobilinogen tests will

usually be within one ‘level of the true concentration. Exact

agreement between visual results and instrumental results

might not be found because of the inherent differences

between the perception of the human eye and the optical

systems of the instruments.

The following table lists the generally detectable levels

of analytes in contrived urine; however, because of the

inherent variability of clinical urines, lesser concentrations

may be detected under certain conditions.

Reagent area Sensitivity

Glucose 75–125 mg/dL glucose

Bilirubin 0.4–0.8 mg/dL bilirubin

Ketone 5–10 mg/dL acetocetic acid

Blood 0.015–0.062 mg/dL hemoglobin

Protein 15–30 mg/dL albumin

Glucose

The test is specific for glucose; no substance excreted

in urine other than glucose is known to give a positive

result. The reagent area does not react with lactose,

galactose, fructose nor reducing metabolites of drugs

(e.g. salicylates and nalidixic acid. This test may be used

to determine whether the reducing substance found

in urine is glucose. Reactivity may be influenced by

urine specific gravity and temperature. In dilute urines

containing less than 5 mg/dL ascorbic acid, as little as 40

mg/dL glucose may produce a color change that might be

interpreted as positive. The test is more sensitive than the

copper reduction test (e.g. Clinitest Reagent Tablets).

If the color appears somewhat mottled at the higher

glucose concentrations, match the darkest color to the

color blocks.

Bilirubin

The test has a sensitivity of 0.4–0.8 mg/dL bilirubin.

Ketone

The test reacts with acetoacetic acid in urine. It does not

react with acetone or (3-hydroxybutyric acid. Some high

specific gravity/low pH urines may give reactions up to and

including Trace. Clinical judgment is needed to determine

the significance of reactions up to and including Trace.

Specific Gravity

The specific gravity test permits determination of urine

specific gravity between 1.000 and 1.030. In general, it

correlates within 0.005 with values obtained with the

refractive index method. For increased accuracy, 0.005

may be added to readings from urines with pH equal

to or greater than 6.5. Strips read instrumentally are

automatically adjusted for pH by the instrument. The

Bayer SG test is not affected by certain nonionic urine

constituents such as glucose nor by the presence of

radiopaque dye.

Urine Analysis 77

Blood

The sensitivity of this test may be reduced in urines with high

specific gravity. The test is equally sensitive to myoglobin as

to hemoglobin. The appearance of green spots on the reacted

reagent area indicates the presence of intact erythrocytes in

the urine. The color chart includes examples of trace and

moderate nonhemolyzed color blocks. Reactions ranging

from trace to large, with proportionately more numerous

spots, may be observed, (A hemoglobin concentration of

0.015-0.062 mg/dL is approximately equivalent to 5–20

intact red blood cells per microliter). Because of the optical

systems of urine chemistry instruments, the sensitivity to

intact erythrocytes is lower than that perceived visually.

pH

The pH test area measures pH values generally to within

1 unit in the range of 5–8.5 visually and 5–9 instrumentally.

pH readings are not affected by variations in the urinary

buffer concentration.

Protein

The reagent area is more sensitive to albumin than to

globulins, hemoglobin, Bence-Jones protein, and mucoprotein; a negative result does not rule out the presence of

these other proteins.

Urobilinogen

This test area will detect urobilinogen in concentrations

as low as 0.2 mg/dL (approximately 0.2 EU/dL) in urine.

The absence of urobilinogen in the specimen cannot be

determined.

Multistix Urinalysis Strips (Fig. 5.3)

FIG. 5.3: Presentation

Dependable Results When and Where You Need

Them

Bayer’s Multistix strips lead the market in providing a

range of rapid urine testing results. When read visually

or automatically on either the Clinitek 50 or Clinitek 500

readers they enable on the spot clinical decisions to be

made with confidence (Table 5.5).

Easy to Use (Figs 5.4 to 5.6)

Rapid Results (Fig. 5.6)

¾ Fast, reliable results available in 1–2 minutes

¾ Automated reading provided in 1 minute using.

TABLE 5.5: Multistix configurations

Leuc Nitrite Urobil Prot pH Blood SG Ket Bill Gluc

Multistix 10 SG √ √ √ √ √ √ √ √ √ √

Multistix 8 SG √ √ √ √ √ √ √ √

Multistix GP √ √ √ √ √ √ √ √

N-Multistix SG √ √ √ √ √ √ √ √ √

Multistix SG √ √ √ √ √ √ √ √

Labstix SG √ √ √ √ √ √

N-Labstix √ √ √ √ √ √

Bili-Labstix √ √ √ √ √ √

Labstix √ √ √ √ √

Hema-Combistix √ √ √ √

Uristix √ √

Albustix √

78 Concise Book of Medical Laboratory Technology: Methods and Interpretations FIG. 5.7: Clinitek status—the instrument

FIG. 5.5: Blot

FIG. 5.4: Dip FIG. 5.6: Read at correct time

First Line Health Screen for a Variety of Settings

¾ Menu: Glucose, ketones, bilirubin, urobilinogen,

specific gravity, blood , pH, protein, nitrite, leukocytes.

Improved Use of Resources

¾ Diabetes Management/Renal checks using microalbumin (Albumin : Creatinine Ratio) while the patient

waits

¾ Screens out non-infected urine samples so that only

the positives need to be referred for laboratory followup in cases of urinary tract infection.

AUTOMATION IN URINALYSIS

Clinitek Status® Urine Analyzer (Fig. 5.7)

Dependable Results in Any Patient Setting

Introducing the new Clinitek Status. Providing simple,

accurate results for higher standards in urinalysis;

Urinalysis has long been an essential tool in health care,

but visually read results may be less than ideal today’s

world. The Clinitek Status can help (Fig. 5.8):

¾ New levels of precision and reliability

¾ Unprecedented convenience

Urine Analysis 79

FIG. 5.8: Clinitek Status instrument (Courtesy: Siemens Medical Solutions)

TABLE 5.6: Specifications

Mains/Battery

(optional)

Dimensions Weight Instrument memory Computer powered

interface

240 V Transformer

(supplied)/6 AA

non-rechargeable

alkaline batteries

(not supplied)

Depth–272 mm

(10.7 inches) Width-171 mm

(6.7 inches)

Height–158 mm

(6.2 inches)

Clinitek status

instrument only

(without batteries or power

supply –1.66 kg (3.65 lbs)

200 patient test

results

200 patient details

(patient’s name and/or

patient identification)

Via RS 232

serial port

¾ Time saving simplicity

¾ Reassuringly proven performance

¾ Minimal training required

¾ Audit compliant

¾ Pregnancy test capability using the NEW CIinitest hCG

¾ Automation reduces the risk of errors.

A Wide Range of Test Parameters

Clinitek status is suitable for use with a wide range of

Multistix tests including:

¾ Multistix 10SG

¾ Multistix 8SG

80 Concise Book of Medical Laboratory Technology: Methods and Interpretations FIG. 5.9: Schematic flow through diagram for ascertaining UTI

FIG. 5.10: Etiological basis of positive test results

Leukocytes A passive result may indicate renal disease or

urinary tract infection

Nitrite A positive result may indicate urinary tract

infection

Urobilinogen

(10SG only)