Pathology Handbook

17α - Hydroxyprogesterone

Clinical Indications

Diagnosis of congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency. Levels may be measured following stimulation with ACTH (Synacthen) in investigation of late onset (or mild) CAH. May also be useful in monitoring response to corticosteroid therapy in CAH due to 21-hydroxylase deficiency.

Request Form

Combined Pathology Blood form (Yellow/Black)

Availability

Analysed by referral laboratory if specific criteria met.

Specific Criteria

Investigation or monitoring of CAH

Turnaround Time

2 weeks

Specimen

Serum or Plasma

Volume

2 ml

Container

Yellow top (SST) tube or Paediatric Red top 

Collection

Take blood before emergency administration of corticosteroids and preferably early morning. Samples should not be taken in newborn infants until more than 48 hours after birth.
In monitoring response to treatment, take blood between 08.00h and 09.00h before initiation of treatment for day and again 2 hours after first dose of corticosteroid.
Blood should be taken basal and at  30 minutes and 60 minutes following  Synacthen.

Lab Handling

Aliquot and store at 4C

Causes for Rejection

Sample from newborn less than 48 hours after birth

Reference Range

Infants >5 days and adults: less than 20 nmol/L

Interpretation

Peak levels following Synacthen: Less than 35 nmol/L excludes CAH, whilst a level greater than 60 nmol/L is consistent with CAH. Levels between 35 and 60 are borderline.