NEONATAL SCREENING (17- ALPHA HYDROXYPROGESTERONE)

Neonatal Screening (17-Alpha Hydroxyprogesterone), commonly called the 17-OHP newborn screening test, measures 17-hydroxyprogesterone in a small blood sample collected from a newborn. It is primarily used to identify babies who may have classic congenital adrenal hyperplasia caused by 21-hydroxylase deficiency.

Congenital adrenal hyperplasia (CAH) is a group of inherited disorders affecting hormone production in the adrenal glands. In the most common form, the body cannot make enough cortisol and may also produce insufficient aldosterone. This causes 17-OHP to accumulate and may lead to excessive androgen production.

Benefits of the Test

• Supports early screening for classic congenital adrenal hyperplasia.
• Measures 17-OHP using a small newborn blood sample.
• Helps identify babies at risk before severe symptoms develop.
• Supports early investigation of potentially dangerous salt-wasting CAH.
• Allows prompt confirmatory testing after an abnormal screen.
• Supports timely referral to a paediatric endocrinologist.
• May help prevent severe dehydration, shock, and other complications.
• Forms an important part of comprehensive neonatal screening.

Why Doctors Recommend This Test

Doctors recommend neonatal 17-OHP screening because babies with classic CAH, particularly affected male infants, may appear normal at birth but can develop a life-threatening adrenal or salt-wasting crisis during the first weeks of life. Early screening allows further testing and treatment to begin before serious complications occur.

Preparation Before Test

• No fasting is required for the newborn.
• Feeding can generally continue as usual unless the paediatrician gives different instructions.
• The sample is commonly collected using a heel prick and applied to a dried-blood-spot card.
• Screening is generally more accurate when the sample is collected after the baby is at least 24 hours old.
• Inform the laboratory if the baby was premature, had a low birth weight, was seriously ill, or received steroid medicines.
• Provide details of maternal steroid treatment during pregnancy when applicable.
• Tell the doctor about any family history of CAH, unexplained neonatal death, or adrenal disorders.

Normal Reporting Time

The Neonatal 17-OHP screening test should be processed promptly because classic CAH can cause serious illness soon after birth. Reporting time depends on sample receipt, dried-blood-spot quality, assay schedules, repeat testing, and quality review. Please confirm the expected turnaround time with Focus Diagnostics when the sample is submitted. An abnormal screening result requires urgent communication and follow-up testing.

Who Should Take This Test?

This screening may be recommended for:

• Newborn babies undergoing routine neonatal screening.
• Babies born in hospitals or maternity centres offering newborn screening.
• Premature or low-birth-weight babies according to repeat-screening protocols.
• Newborns with ambiguous or atypical genital development.
• Babies with poor feeding, vomiting, dehydration, or inadequate weight gain.
• Newborns with low sodium or high potassium levels.
• Babies with a family history of congenital adrenal hyperplasia.
• Newborns requiring repeat testing after an early or unsuitable sample.

Detailed Information

17-hydroxyprogesterone is a hormone precursor used by the adrenal glands to produce cortisol. The enzyme 21-hydroxylase is required during this process. When the enzyme is deficient, cortisol production decreases and 17-OHP accumulates in the blood.

Most CAH detected by newborn screening is caused by disease-causing variants in the CYP21A2 gene. The condition is inherited in an autosomal-recessive pattern, which generally means an affected baby has inherited one disease-causing variant from each parent.

Classic CAH includes salt-wasting and simple-virilising forms. In salt-wasting CAH, the baby may not produce enough cortisol or aldosterone. This can cause vomiting, poor feeding, dehydration, weight loss, low blood pressure, low sodium, high potassium, and shock.

Female infants with classic CAH may be born with atypical external genital development because of increased androgen exposure. Male infants may appear physically typical at birth, making biochemical screening especially important.

The preferred screening sample is commonly a dried blood spot collected by heel prick. Samples taken before 24 hours of age may be more difficult to interpret because 17-OHP can be naturally elevated shortly after birth. Repeat screening may be recommended when an early sample cannot be avoided.

Premature, low-birth-weight, stressed, or seriously ill babies may have elevated 17-OHP without having CAH, resulting in a false-positive screen. Age, birth weight, gestational age, health status, and assay-specific cut-offs must therefore be considered.

Maternal or neonatal steroid treatment may suppress 17-OHP and contribute to a false-negative result. Some babies may also develop elevated levels only after the initial sample, so repeat testing may be required according to clinical findings and newborn-screening protocols.

An out-of-range screening result does not confirm CAH. The baby may need urgent repeat or confirmatory testing, including serum 17-OHP, electrolytes, glucose, cortisol, plasma renin, other adrenal steroids, and CYP21A2 genetic testing.

A normal screen reduces the likelihood of classic 21-hydroxylase-deficient CAH but does not detect every case, mild non-classic CAH, or all other rare forms of congenital adrenal hyperplasia. Clinical symptoms must always be investigated even when screening is normal.

Parents should seek urgent medical care if a newborn develops repeated vomiting, poor feeding, unusual sleepiness, dehydration, reduced responsiveness, significant weight loss, or signs of shock. Screening results should not delay emergency assessment.

At Focus Diagnostics, neonatal 17-OHP screening is coordinated using validated newborn-screening methodologies, dried-blood-spot quality requirements, and established quality-control procedures to support reliable early-risk assessment.