NEOXPERT by TMS – Newborn Screening 40+ Analytes

NEOXPERT by TMS is an expanded newborn screening panel that analyses more than 40 biochemical markers from a dried blood spot using tandem mass spectrometry. It is designed to identify babies who may be at increased risk of selected inherited metabolic disorders before obvious symptoms develop.

The panel is also described as a newborn screening panel of approximately 42 analytes. These analytes generally include amino acids and acylcarnitines whose concentrations or ratios may become abnormal in disorders of amino-acid metabolism, organic-acid metabolism and fatty-acid oxidation.

Many screened disorders are individually rare, but delayed recognition can lead to feeding difficulty, vomiting, low blood glucose, abnormal acidity, seizures, liver dysfunction, developmental impairment, coma or other serious complications. Early screening creates an opportunity for prompt confirmatory testing and treatment when required.

NEOXPERT is a screening test and not a final diagnostic test. An abnormal or screen-positive result means that the baby requires further assessment; it does not confirm that the baby has a metabolic disorder. A normal result substantially reduces the likelihood of the screened conditions but cannot exclude every inherited or metabolic disease.

What Is Newborn Screening?

Newborn screening is the systematic testing of babies shortly after birth for selected conditions that may not be visible during a routine physical examination. A newborn can appear healthy while an inherited enzyme or transport defect is already affecting how nutrients are processed.

The purpose of screening is to identify an increased biochemical risk before irreversible complications occur. When screening suggests a possible disorder, the paediatrician or metabolic specialist arranges diagnostic testing and decides whether treatment should begin urgently.

Newborn screening does not replace clinical observation. A baby with poor feeding, repeated vomiting, lethargy, seizures, breathing difficulty, unusual movements, jaundice or another concerning symptom requires immediate medical assessment even when the screening result is normal or pending.

What Does TMS Mean?

TMS refers to tandem mass spectrometry, commonly abbreviated as MS/MS. This analytical technology measures multiple metabolites in a small dried blood spot during a single laboratory run. It evaluates characteristic patterns of amino acids, acylcarnitines and calculated ratios.

The first stage separates selected molecules according to their mass-to-charge characteristics. The molecules are then fragmented and assessed again, allowing the laboratory to recognise biochemical patterns associated with different metabolic pathways.

TMS allows many markers to be analysed from a few drops of blood. The number of measured analytes is not necessarily the same as the number of disorders screened. A single condition may influence several markers, while one marker may be relevant to more than one condition.

Which Types of Disorders May Be Screened?

The exact analytes, ratios and disorders included depend on the laboratory's current validated panel. Parents and clinicians should refer to the official NEOXPERT report or panel list rather than assuming that every metabolic disorder is included.

Amino-Acid Metabolism Disorders

Amino acids are components of proteins. After feeding, proteins are digested into amino acids that are used for growth, tissue repair and energy-related processes. Enzyme deficiencies may prevent a particular amino acid from being processed normally.

TMS panels may detect patterns associated with selected amino-acid disorders such as phenylalanine, branched-chain amino-acid, methionine, citrulline or tyrosine pathway abnormalities. Examples commonly associated with expanded newborn screening include phenylketonuria, maple syrup urine disease, homocystinuria and selected urea-cycle or tyrosine-metabolism disorders. Inclusion and detection performance must be confirmed from the laboratory-specific panel.

Organic Acidaemias

Organic acidaemias are inherited disorders in which the body cannot properly process certain amino acids, fats or related compounds. Abnormal organic acids and acylcarnitines may accumulate and disturb acid-base balance, glucose regulation and energy production.

Potential clinical effects can include poor feeding, vomiting, dehydration, lethargy, abnormal muscle tone, low blood glucose, metabolic acidosis and encephalopathy. TMS may identify characteristic acylcarnitine patterns that prompt confirmatory urine organic-acid and molecular testing.

Fatty-Acid Oxidation Disorders

Fatty-acid oxidation enables the body to use stored fat for energy, particularly during fasting, illness or increased energy demand. A baby with a fatty-acid oxidation defect may be unable to generate adequate energy when feeding is interrupted.

Some affected babies remain well until a period of illness or prolonged fasting triggers low blood glucose, lethargy, liver dysfunction, muscle symptoms or cardiac complications. Screening evaluates acylcarnitine profiles that may indicate selected short-, medium-, long- or very-long-chain pathway disorders.

Why Is Early Screening Important?

Newborns with an inherited metabolic disorder may initially appear healthy because maternal circulation and placental support protected them before birth. Symptoms may develop only after feeding begins, fasting occurs or abnormal metabolites accumulate.

For certain disorders, early dietary treatment, avoidance of fasting, special formulas, vitamin or cofactor supplementation, medicines and emergency illness plans can reduce the risk of serious complications. The exact treatment depends on the confirmed condition and must be supervised by a metabolic specialist.

Who Should Undergo the NEOXPERT Test?

The panel is intended primarily for newborn babies. It may be recommended as part of expanded newborn screening even when there are no symptoms or known family history. Most babies identified through screening are born to parents without a previously recognised metabolic disorder.

Screening may be particularly important when there is a family history of an inherited metabolic disorder, previous unexplained neonatal death, parental consanguinity, an affected sibling or concerning symptoms. In high-risk situations, the doctor may order immediate diagnostic tests in addition to screening.

When Should the Sample Be Collected?

Collection is commonly recommended approximately 48 to 72 hours after birth, preferably after the baby has received feeds. Timing requirements can vary with the hospital, laboratory protocol and clinical condition.

A sample obtained very early may not show a sufficiently developed metabolic pattern and may require repeat collection. Screening should not be unnecessarily delayed when early discharge is planned. The paediatrician or laboratory should arrange the initial sample and any required repeat specimen.

Premature or Unwell Babies

Prematurity, low birth weight, severe illness, liver immaturity, renal immaturity, total parenteral nutrition, certain medicines and intensive-care treatment can influence metabolite concentrations. These factors may cause false-positive, false-negative or difficult-to-interpret results.

Premature or hospitalised babies may require repeat specimens at protocol-defined intervals. Screening should be coordinated by the neonatal team, particularly when the baby is receiving intravenous nutrition.

Blood Transfusion

Transfusion may affect some newborn-screening tests. Whenever possible, the initial dried blood spot should be collected before transfusion without delaying urgent treatment. If the baby has already received blood, the collection card and request form must record the transfusion date and time.

The doctor or laboratory will determine whether a repeat specimen is required. Parents should not decide the collection timing without professional advice.

Which Sample Is Required?

The test generally uses a dried blood spot collected on a special newborn-screening filter-paper card. A trained healthcare professional obtains a few drops of capillary blood, usually from the baby's heel, and applies them directly to the marked circles on the card.

The blood must soak through the filter paper evenly. The card is allowed to dry completely in a clean environment before being packaged and transported according to laboratory instructions.

How Is the Heel-Prick Sample Collected?

1. The baby's identity and clinical details are confirmed.
2. The heel is warmed when appropriate to improve blood flow.
3. A suitable area on the side of the heel is cleaned and allowed to dry.
4. A sterile newborn lancet is used to make a small puncture.
5. Free-flowing drops are applied to the filter-paper circles.
6. The card is dried horizontally without direct heat or sunlight.
7. The dried specimen is sent to the laboratory with complete clinical information.

The procedure may cause brief discomfort. Excessive squeezing should be avoided because it can mix tissue fluid with the blood and reduce specimen quality.

Why Is Dried Blood Spot Quality Important?

An insufficient, layered, clotted, contaminated, wet or uneven blood spot may be unsuitable for analysis. Applying blood to both sides of the card, touching the collection area or packaging the card before it is dry can also affect testing.

If the specimen fails quality checks, a repeat heel-prick collection may be requested. Recollection does not necessarily mean that the baby's result was abnormal; it may only mean the original specimen was inadequate.

Is Fasting Required?

Fasting is not required and should not be imposed on a newborn for this screening test. Babies should follow the feeding plan recommended by the paediatrician or neonatal team.

Information about breast milk, standard formula, specialised formula, intravenous nutrition and the time feeds began should be provided when requested because nutritional status can influence some metabolites.

How Is the Sample Analysed?

A small disc is punched from the dried blood spot, and metabolites are extracted in the laboratory. Tandem mass spectrometry measures the selected amino acids and acylcarnitines. Software and trained laboratory professionals assess concentrations, ratios and patterns using newborn-specific decision limits.

Results may be classified as within screening limits, borderline, screen-positive or requiring repeat collection. Decision limits are not the same as diagnostic reference ranges. They are selected to identify babies who require additional evaluation while balancing false-positive and false-negative results.

Understanding the Result

Screen-Negative Result

A screen-negative result means that the measured markers did not exceed the programme's action limits. It reduces the likelihood of the screened disorders but does not provide a lifetime guarantee of health.

Not every genetic or metabolic condition is included, and some affected babies may have marker concentrations below the cutoff at the time of collection. Symptoms always take priority over a previous screening result.

Borderline Result

A borderline result may occur because of early collection, prematurity, illness, nutrition, medicine exposure or minor biochemical variation. The laboratory may request another dried blood spot or recommend targeted testing.

Parents should arrange recollection promptly. A borderline result does not mean that a disorder has been diagnosed.

Screen-Positive Result

A screen-positive result indicates an increased risk of a specific metabolic disorder or group of disorders. It is not a confirmed diagnosis. The paediatrician may contact the family urgently and arrange confirmatory testing.

Depending on the suspected condition, temporary precautions such as avoiding prolonged fasting or following an emergency feeding plan may be recommended while results are pending. Parents should follow only the instructions given by the treating medical team.

Confirmatory Tests That May Be Required

Further investigations depend on the abnormal screening pattern and may include:

• Quantitative plasma amino-acid analysis.
• Plasma acylcarnitine profile.
• Urine organic-acid analysis.
• Blood glucose, ammonia, lactate and blood-gas testing.
• Liver-function, kidney-function and electrolyte tests.
• Specific enzyme-activity assays.
• Targeted metabolite testing.
• Molecular genetic testing.
• Testing of parents or siblings when appropriate.
• Assessment by a paediatric metabolic specialist and genetic counsellor.

Can an Abnormal Result Be a False Positive?

Yes. Screening prioritises sensitivity, so some babies with an abnormal result will not have the suspected disorder after confirmatory testing. Prematurity, early collection, illness, nutrition and medication can influence results.

False-negative results are also possible. The test should never be used to dismiss symptoms or replace diagnostic evaluation in a clinically unwell baby.

Benefits and Limitations

The principal benefit is the ability to screen multiple metabolic pathways using a small dried blood spot before symptoms develop. Early detection can support timely treatment and may reduce preventable complications in affected babies.

Limitations include false-positive and false-negative results, variation in the disorders included, dependence on collection timing and specimen quality, and the need for confirmatory testing. The panel does not analyse the baby's complete genome and does not screen for every congenital, endocrine, genetic or infectious condition.

NEOXPERT by TMS at Focus Diagnostics

NEOXPERT by TMS (Newborn Screening 40+ Analytes) is available under the pathology and bio-chemistry department at a listed price of ₹5,500. The panel is commonly described as analysing approximately 42 markers in a dried blood spot.

Parents should confirm the current price, ideal collection time, exact panel composition and expected reporting time while booking. Provide the baby's gestational age, birth weight, feeding details, transfusion history, medicines and neonatal intensive-care information.

Important Parent Instructions

• Arrange collection according to the paediatrician's recommended timing.
• Do not fast the baby for this screening test.
• Provide complete feeding, transfusion and clinical information.
• Respond promptly if repeat collection is requested.
• Do not interpret a screen-positive result as a confirmed diagnosis.
• Seek urgent care if the baby becomes unwell, regardless of screening status.

Medical Disclaimer

This information is intended for general education and does not replace paediatric medical advice. NEOXPERT by TMS is a newborn screening panel, not a diagnostic test. Screen-positive, borderline and negative results require interpretation according to the baby's age, feeding status, clinical condition and laboratory protocol. Confirmatory testing is essential before a metabolic diagnosis is established.