Who Should Take a FRAT Test? Signs You Should Not Ignore

Not every child with developmental delays needs a FRAT test. But for a significant number of children — and even some adults — getting this test at the right time could unlock a diagnosis that changes the entire trajectory of their care. The challenge is knowing when the signs are pointing clearly enough to warrant investigation.

This guide is designed to help parents, caregivers, and even healthcare professionals understand exactly who should consider FRAT testing and which warning signs should never be dismissed or attributed simply to “late development.”

Understanding Why the FRAT Test Is Not Routine

The FRAT test (Folate Receptor Antibody Test) is a specialised diagnostic test that detects autoantibodies against the Folate Receptor Alpha (FRα) protein — the biological gateway that carries folate from the blood into the brain. Because this test is not part of standard developmental screening panels, it is often overlooked unless a clinician or an informed parent specifically requests it.

This gap in awareness means that children with Cerebral Folate Deficiency (CFD) — a treatable neurological condition caused by these autoantibodies — may go undiagnosed for years, sometimes receiving other diagnoses when the root cause is actually autoimmune-mediated folate transport failure. You can learn the detailed science behind this in our guide to the FRAT test: symptoms, causes, procedure, and treatment.

Primary Candidates: Children Who Should Be Tested

1. Children Diagnosed with Autism Spectrum Disorder (ASD)

ASD is the single strongest indicator for FRAT testing. Multiple independent research groups have found that 60–75% of children with ASD test positive for Folate Receptor Autoantibodies. Crucially, children with ASD who are FRAT-positive and treated with folinic acid have shown measurable improvements in language, social behaviour, and cognitive function.

This is especially relevant for:

• Children with regressive autism — where skills developed and then were lost
• Children with ASD who have not responded adequately to standard therapies (ABA, speech therapy, OT)
• Children with ASD plus seizures, gastrointestinal symptoms, or sleeping difficulties
• Children whose ASD was preceded by a period of apparent typical development

2. Children with Unexplained Speech or Language Delays

Language delay is one of the earliest and most prominent symptoms of Cerebral Folate Deficiency. If a child who was beginning to develop words suddenly stops, or a child reaches the age of 2–3 without meaningful words despite apparently normal hearing and social engagement, FRAT testing is worth discussing with a paediatric neurologist.

The key distinguishing factor is that the delay occurs without another clear explanation — no hearing loss, no structural brain abnormality on MRI, and no chromosomal or genetic disorder that fully accounts for the severity of the delay.

3. Children with Infantile Spasms or Treatment-Resistant Epilepsy

Infantile spasms (West syndrome) and other forms of early-onset epilepsy can be early manifestations of Cerebral Folate Deficiency. Children whose seizures do not respond to first- or second-line anticonvulsant medications, or who develop epilepsy alongside developmental regression, should be evaluated for FRAT positivity as part of their metabolic workup.

In some cases, treating the underlying folate transport deficiency with folinic acid has resulted in dramatic reduction or complete cessation of seizure activity that was previously refractory to multiple medications.

4. Children with Developmental Regression

Perhaps one of the most alarming warning signs that parents should never ignore is developmental regression — when a child who has been developing normally suddenly loses skills they had previously mastered. This includes loss of:

• Words or sentences they were using regularly
• Social skills — eye contact, responding to their name, interactive play
• Motor abilities — walking, fine motor tasks, self-care skills

Regression in a previously typical child is always a medical emergency that warrants urgent neurological evaluation, and FRAT testing should be part of that evaluation alongside MRI, metabolic screening, and genetic workup.

5. Children with Intellectual Disability of Unknown Cause

When a child presents with intellectual disability and the standard diagnostic workup — chromosomal microarray, whole exome sequencing, metabolic screen — does not identify a clear cause, Folate Receptor Autoimmunity should be considered. CFD is a metabolic cause of intellectual disability that is specifically treatable, making identification particularly important.

6. Children with Hypotonia (Low Muscle Tone)

Hypotonia is a common early feature of CFD, particularly in infants. While low muscle tone has many causes, infants who present with hypotonia alongside feeding difficulties, developmental delay, and irritability should be evaluated for metabolic and autoimmune causes, including Folate Receptor Autoimmunity.

Secondary Candidates: Adults and Pregnant Women

Adults with Treatment-Resistant Psychiatric Conditions

Emerging research has linked Folate Receptor Autoimmunity to treatment-resistant schizophrenia, bipolar disorder with psychotic features, and severe depression in adults. Adults whose psychiatric symptoms have not responded to standard pharmacological treatment, particularly when there is also a family history of ASD or metabolic disorders, may benefit from FRAT testing.

Women Who Are Pregnant or Planning Pregnancy

Testing during pregnancy is an important emerging use of the FRAT test. A mother who is FRAT-positive can pass both the autoantibodies and potentially the risk to her developing foetus. Our detailed guide on FRAT testing during pregnancy explains why maternal FRAT status matters and what interventions are available.

Siblings of FRAT-Positive Children

If one child in a family has tested FRAT positive, there is an increased likelihood that siblings — particularly younger ones — may also carry Folate Receptor Autoantibodies. Proactive testing of siblings can facilitate early intervention before significant symptoms develop.

Warning Signs You Should Not Ignore: A Quick Reference

The following checklist summarises the most important red flags. If your child or family member has three or more of these signs, we strongly recommend discussing FRAT testing with a specialist:

• Diagnosis of autism spectrum disorder, particularly with regression
• No meaningful words by age 2 or loss of words after developing them
• Seizures that are difficult to control or began in infancy
• Progressive loss of motor skills or coordination
• Unexplained intellectual disability
• Significant behavioural regression after a period of normal development
• Family history of autoimmune conditions (thyroid disease, rheumatoid arthritis, IBD)
• History of heavy cow’s milk or dairy consumption in the child’s diet
• Chronic sleep disruption, unexplained irritability, or sensory hypersensitivity
• Normal blood folate levels despite clinical signs suggesting folate deficiency

What Happens If You Delay Testing?

The central reason why early FRAT testing matters is neuroplasticity — the brain’s capacity for repair and reorganisation is greatest in the early years of life. Every month of untreated Cerebral Folate Deficiency in a young child is a month during which brain development is being compromised by inadequate folate supply.

Clinical evidence consistently shows that children who begin folinic acid treatment earlier — ideally before the age of 5 — achieve significantly better outcomes than those who are diagnosed and treated later. This is not to say that treatment is ineffective after age 5 — many older children and adults have shown meaningful improvement — but the window for maximum neurological recovery is narrowest early in life.

To learn more about what happens after a positive result and what to do next, read our comprehensive guide: FRAT Test Positive? Here’s What It Means and What to Do Next.

How to Get a FRAT Test in India

Altus Lab Chandigarh provides FRAT / FOLR1 Antibody testing with specialist oversight. We offer free home blood collection in Chandigarh, Mohali, and Panchkula, and a pan-India sample collection kit service for families across the country.

Our reports are accepted at leading hospitals including PGIMER Chandigarh, Fortis Mohali, and Max Hospital. To book your test or speak with our team, visit our FRAT test page or explore our complete guide to FRAT testing at home.

Frequently Asked Questions

My child has ASD but seems high-functioning. Should they still be tested?

Yes. FRAT positivity is not limited to children with severe ASD. Children on the higher-functioning end of the autism spectrum have also been found to carry Folate Receptor Autoantibodies. Treatment with folinic acid has produced improvements in social communication, academic performance, and emotional regulation even in children who were previously considered to be managing well.

Can a FRAT test be done privately without a referral?

In India, the FRAT test can be booked through Altus Lab without a formal referral, though we always recommend involving a paediatric neurologist or developmental paediatrician who can provide clinical context for the result. A referral helps ensure that a positive result triggers appropriate treatment rather than remaining unacted upon.

How is the FRAT test different from a standard folate blood test?

A standard serum folate test measures the amount of folate circulating in the bloodstream — which is almost always normal in FRAT-positive children. The FRAT test instead measures the presence of autoantibodies that block folate transport into the brain. These are entirely different measurements, and a normal serum folate does not rule out Cerebral Folate Deficiency.