Newborn Screening Act of 2004

Newborn screening (NBS) is a public health program in the Philippines, established in June 1996 and integrated into public health delivery by the Newborn Screening Act of 2004. This act mandates a national system for early identification of disorders that can lead to intellectual disability and death if left untreated.

Currently, there are seven operational NBS centers across the Philippines, handling samples from various regions. The National Institutes of Health (NIH) at UP Manila covers NCR, Region 4B, and 5. Other centers include Central Luzon (Angeles City), Southern Luzon (Tanauan City), Northern Luzon (Ilocos Norte), Central Visayas (Mandaue City), and Iloilo City (for Regions 6 and 8). The Southern Philippines Medical Center in Davao caters to all Mindanao regions. These centers not only conduct laboratory analyses but also manage short-term and long-term follow-up programs for affected infants.

NBS is crucial because many genetic disorders are not identifiable at birth through physical examination. Symptoms often appear later, when irreversible damage may have already occurred. Early identification and timely intervention can significantly reduce morbidity, mortality, and disabilities. The expanded newborn screening (ENBS) introduced in 2014 screens for 29 disorders, an increase from the initial six, providing more opportunities for better health outcomes.

The video explains the use of tandem mass spectrometry (TMS) for metabolic disorders and high-performance liquid chromatography (HPLC) for hemoglobinopathies. It emphasizes that NBS and ENBS are screening, not diagnostic, tests. Results are generally valid for newborns less than 28 days old, with samples ideally taken 24 hours after birth and delivered to the lab within four days. The importance of the 'golden period' for intervention is highlighted, citing critical treatment windows for conditions like Congenital Adrenal Hyperplasia (CAH) and Maple Syrup Urine Disease (MSUD).

The presentation lists the disorders included in the expanded newborn screening panel, categorized into standard NBS conditions, hemoglobinopathies, amino acid disorders, organic acid disorders, fatty acid oxidation disorders, and other conditions like cystic fibrosis. It details the specific confirmatory tests required for various conditions, such as serum TSH/fT4 for congenital hypothyroidism and 17-OHP for CAH. These confirmatory tests are provided free for patients with positive screening results.

As of December 2020, G6PD deficiency and congenital hypothyroidism are the most common disorders detected. The video explains the fundamental principles of IEM, which are typically caused by enzyme defects leading to metabolic pathway blockages, resulting in toxic substrate accumulation or product deficiency. Most IEMs follow an autosomal recessive inheritance pattern, meaning parents are usually carriers and there's a 25% chance for offspring to inherit the disease if both parents are carriers.

A case of a 9-day-old neonate with ambiguous genitalia, seizures, vomiting, hyponatremia, hyperkalemia, and hypoglycemia is presented as classical CAH, salt-wasting type, with adrenal crisis. The pathophysiology involving 21-hydroxylase deficiency and the accumulation of 17-OHP is explained. Clinical features in females include ambiguous genitalia and salt-wasting crises. Management involves immediate emergency treatment, IV fluids, hydrocortisone, mineralocorticoid supplementation, and sodium chloride.

A 5-day-old exclusively breastfed boy with a high TSH level (80 mIU/L) leading to a diagnosis of CH. The video describes that most affected infants appear normal at birth due to maternal thyroid hormone passage. Clinical manifestations, if present, include wide sutures, flat nasal bridge, macroglossia, umbilical hernia, and prolonged jaundice. Treatment involves lifelong levothyroxine supplementation.

A 5-day-old boy with increased sleepiness, difficult arousal, hypertonia, and sweet-smelling urine, showing increased branched-chain amino acids (BCAA) in plasma, is diagnosed with MSUD. This amino acid disorder is the most common IEM in the Philippines. Management involves protein limitation, special BCAA-free formula (B-Carb), and during metabolic crisis, high caloric intake and potential dialysis.

A 7-day-old girl with jaundice, bleeding episodes, hypoglycemia, hepatomegaly, ascites, and renal tubular acidosis, showing increased succinyl acetone and tyrosine, is diagnosed with Tyrosinemia Type 1. This deficiency leads to toxic metabolite accumulation in the liver and kidneys. Treatment includes a specific pharmacologic agent (NTBC) and a protein-restricted diet with a special tyrosine-free amino acid formula.

A 6-day-old boy with lethargy, vomiting, leucopenia, thrombocytopenia, metabolic acidosis, and hyperammonemia, with MMA detected in urine, is presented. This organic acid disorder causes methylmalonate accumulation, toxic to the brain and kidneys. Management involves a low-protein diet, special formula free of specific amino acids, L-carnitine supplementation, metronidazole, and vitamin B12.

A 6-year-old girl with seizures, hypotonia, and symmetric rash, showing decreased biotinidase activity on newborn screening, has biotinidase deficiency. This leads to the inability to recycle biotin, causing neurological symptoms and lactate accumulation. Treatment is simple: chronic oral administration of biotin.

A 5-day-old boy with vomiting, lethargy, encephalopathy, hepatomegaly, and hyperammonemia is diagnosed with Citrullinemia. This defect in the urea cycle leads to increased plasma citrulline and ammonia levels. Treatment involves a low-protein diet, arginine supplementation, and sodium benzoate to eliminate toxic chemicals.

A 7-day-old boy not feeding well, presenting with hypoglycemia, and with an older brother who died from similar symptoms, indicates a FAOD. These disorders impair fat metabolism, leading to hypoketotic hypoglycemia. Management focuses on preventing fasting by ensuring adequate carbohydrate intake, especially for infants who need frequent feeding (every 3-4 hours) and avoid prolonged fasting (over 6-8 hours).

Early screening is critical to prevent negative effects like recurrent illnesses, developmental disabilities, or death from these disorders. Conditions like CH, CAH, MSUD, PKU, G6PD deficiency, and other metabolic disorders can lead to severe mental retardation, coma, or death if untreated. Newborn screening, therefore, is vital for saving lives and improving the quality of life for affected newborns.