PREDNISOLONE METABOLISM TEST

PREDNISOLONE METABOLISM TEST

Aim: 

To assess prednisolone metabolism in steroid dependent asthmatics

Justification:

Small group of asthmatics remain symptomatic despite long term treatment with oral corticosteroids “prednisolone”, with major implication in terms of steroid induced side effects.  The cause of this lack of effect could be due to poor adherence, malabsorption, rapid metabolism or genetically mediated resistance to steroids.  The aim of this test is to assess the cause of the apparent lack of responsiveness to steroids in a patient.

Procedure:

• Collect 5ml blood for baseline measurement into a plain/ gel tube (“clotted sample”) at approximately 8.30am.
  Label “Pre-Prednisolone – 8.30am”
• Administer standardised dose (0.5mg/kg) of Prednisolone. E.g. 60kg = 30mg. “this need to be directly observed by a medical staff” at 8.30 am.
• Collect 1 sample of 5ml of blood at 9.00am, and then 5ml samples at 10.00 am, 11.00 am, 12.00pm.
• Please label accurately each sample time on the tube.

Sample Requirements:

• Total of 6 samples.
• Serum (yellow or red top tube)
• Minimum volume of each sample = 5ml whole blood

Request Form:

• One request form should be completed for all samples.
• Request ‘STEROID ABSORPTION TEST’. F.A.O: Ms Joanne Heynes.
• State time of sample on each bottle.
• Transport to Clinical Biochemistry, BHH.

Notes:

• Please ensure patient does not take their morning dose of prednisolone prior to starting the test.

Please record the following clinical information and send to the laboratory with the samples:

1. 1. Steroid dependent asthma:  Yes  /  No  (Asthma classification:                      )
2. 2. Asthma Control (yes / no): Good, suboptimal, poor
3. 3. Adherence compliance:
   1.  a: All the time,  b: most of the time, c: good amount of time, d: sometimes, e: not at all
4. 4. Is patient on theophylline: Yes / No.  If yes what is the dose, serum level
5. 5. What is the baseline prednisolone dose:……mg/day,duration:…..months….years.
   1. Frequency of increase of dose over last 12 months…….
6. 6. Steroid side effects
   1. Truncal obesity: yes/no, 
   2. Pink striae yes/no,
   3. Moon face  yes/no,
   4. Skin bruising  yes/no,
   5. Cataract  yes/no,
   6. Osteoporosis  yes/no,
   7. Diabetes mellitus yes/no,
   8. Hypertension yes/no,
   9. IHD yes/no,
   10. Previous evidence of adrenal suppression.
7. 7. Asthma responsiveness of prednisolone: yes/no , any steroid reversibility trial
8. 8.  Peripheral blood eosinophil……., exhaled nitric oxide……, FEV1……. (%pred….)
9. 9. sex,   age,    weight,      height,        BMI
10. 10.  Smoking history: never smoked, exsmoker….., current smoker… Pack yrs.
11. 11. Which category the patient fall in:
    • a) Slim patient with no steroid toxicity and poor asthma control
    • b) Slim patient with steroid toxicity and poor asthma control
    • c) Clinically cushinoid with steroid toxicity and good asthma control
    • d) Clinically cushinoid with steroid toxicity and poor asthma control