Bilirubin Auto Direct FS*

Question 1

Intended Use?

Answer 1

Diagnostic reagent for quantitative in vitro determination of direct
bilirubin in human serum or heparin plasma on automated
photometric systems.

Question 2

Note:
Bilirubin is a breakdown product of hemoglobin. Free,
unconjugated bilirubin is extremely apolar and nearly insoluble in water, thus forming a complex with albumin for the transport in blood ✅from the spleen to the liver. In the liver, bilirubin is conjugated with ✅glucoronic acid and the resulting water soluble bilirubin glucoronic acid is excreted ✅via the bile ducts.
✅Hyperbilirubinemia can be caused by increased bilirubin production
due to hemolysis ✅(pre-hepatic jaundice), by parenchymal damages
of the liver (intra-hepatic jaundice) or by ✅occlusion of bile ducts (post-hepatic jaundice).

A chronic congenital (predominantly unconjugated) hyperbilirubinemia called Gilbert’s syndrome is quite
frequent in the population. High levels of total bilirubin are observed in ✅60 – 70% of neonates due to an increased postpartum breakdown of erythrocytes and because of delayed function of enzymes for bilirubin degradation.

✅ Common bilirubin methods detect either ✅Total bilirubin or Direct bilirubin. ✅Determinations of
direct bilirubin measure mainly conjugated, water soluble bilirubin. Therefore, the value of unconjugated bilirubin may be estimated from the difference between total bilirubin and direct bilirubin.

Answer 2

🩵

Question 3

Reagents
Components and Concentrations

Answer 3

R1:
✅EDTA-Na2 - 0.1 mmol/L
✅NaCl - 150 mmol/L
✅Sulfamic acid - 100 mmol/L

R2:
✅2,4-Dichloroaniline - 0.5 mmol/L
✅HCl - 900 mmol/L
✅EDTA-Na2- 0.13 mmol/L

Question 4

Note: Reagents are stable up to the date of expiry indicated on the kit, if stored at 🩵2 – 8°C and contamination is avoided. Do not freeze and protect from light.

Answer 4

🩵

Question 5

Warnings and Precautions
(Reagent 1 and 2)

May be corrosive to
metals.

Answer 5

H290

Question 6

Warnings and Precautions
(Reagent 1 and 2)

Keep only in original packaging.

Answer 6

P234

Question 7

Warnings and Precautions
(Reagent 1 and 2)

Absorb spillage to prevent material damage.

Answer 7

P390

Question 8

In very rare cases, samples of patients with____
might give falsified results [

Answer 8

gammopathy

Question 9

_____medication leads to falsely low or high results in
patient samples.

Answer 9

Eltrombopag

Question 10

Specimen

Answer 10

Human serum or heparin plasma

Question 11

Stability

Answer 11

✅ 2 days at 20 – 25°C
✅ 7 days at 4 – 8°C
✅ 6 months at –20°C

Question 12

Wavelength

Answer 12

545/658 nm

Question 13

Temperature

Answer 13

37°C

Question 14

Measurement

Answer 14

Endpoint

Question 15

Sample/Calibrator

Answer 15

3.5 µL

Question 16

Reagent 1

Answer 16

80 µL

Question 17

Reagent 2

Answer 17

20 µL

Question 18

DiaSys TruCal U is recommended for calibration. Calibrator values
have been made traceable to the manual ✅ Jendrassik-Gróf test.
Use DiaSys TruLab N and P for internal quality control. Each
laboratory should establish corrective action in case of deviations in control recovery.

Answer 18

🩵

Question 19

Limit of detection**

Answer 19

0.01 mg/dL

Question 20

Interfering substance

Interferences ≤ 10% up to: ???

Answer 20

✅Ascorbic acid ……. 30 mg/dL

✅Hemoglobin ……interferes at low concentrations

✅Lipemia (triglycerides) ……600 mg/dL

Question 21

Method comparison

Answer 21

(n=109)

Question 21

Reference Range in ADULTS and CHILDREN

Answer 21

✅ ≤ 0.2 mg/dL
✅ ≤ 3.4 µmol/L

Question 22

Give at least three (3) causes of Hyperbilirubinemia

Answer 22

✅1. Hemolysis (Pre-hHepatic Jaundice)

✅2. Parachyamal damages of the liver (Intra-Hepatic Jaundice)

✅3. Occlusion of bile ducts (Post-Hepatic Jaundice)

Question 23

Medication that leads to falsely low or high bilirubin results in px samples.

Answer 23

Eltrombopag