Diseases Detected by Newborn Screening in the Philippines

The disorders included in the newborn screening package were Congenital Hypothyroidism, Congenital Adrenal Hyperplasia, Galactosemia, Phenylketonuria and Glucose 6-Phosphate Dehydrogenase Deficiency.

Congenital Adrenal Hyperplasia

Congenital adrenal hyperplasia is an endocrine disorder that causes severe salt loss, dehydration of high levels of male sex hormones in both boys and girls. If not treated, babies may die within 7-14 days. (Harrow, CM, 2011)

Congenital adrenal hyperplasia can affect both boys and girls. People with congenital adrenal hyperplasia lack an enzyme needed by the adrenal gland to make the hormones cortisol and aldosterone. Without these hormones, the body produces more androgen, a type of male sex hormone. This causes male characteristics to appear early (or inappropriately). About 1 in 10,000 to 18,000 children are born with congenital adrenal hyperplasia. Girls will usually have normal female reproductive organs (ovaries, uterus, and fallopian tubes). They may also have the following changes such as abnormal menstrual periods, deep voice, early appearance of pubic and armpit hair, excessive hair growth and facial hair, failure to menstruate and Genitals that look both male and female (ambiguous genitalia), often appearing more male than female. Boys won't have any obvious problems at birth. However, they may appear to enter puberty as early as 2 - 3 years of age. Changes may include deep voice, early appearance of pubic and armpit hair, early development of male characteristics, enlarged penis, small testes and well-developed muscles. Both boys and girls will be tall as children but much shorter than normal as adults. Some forms of congenital adrenal hyperplasia are more severe and cause adrenal crisis in the newborn due to a loss of salt. Newborns with these forms develop severe symptoms shortly after birth, including cardiac arrhythmias, dehydration, electrolyte changes and vomiting. The goal of treatment is to return hormone levels to normal. This is done by taking a form of cortisol (dexamethasone, fludrocortisone, or hydrocortisone) every day. People may need additional doses of medicine during times of stress, such as severe illness or surgery. People with this condition usually have good health. However, they may be shorter than normal, even with treatment. Males have normal fertility. Females may have a smaller opening of the vagina and lower fertility. People with this disorder must take medication their entire lives.

The health care provider will determine the gender of a baby with ambiguous genitalia by checking the chromosomes (karyotyping). Girls with male-looking genitals will usually have surgery between ages 1 month - 3 months to correct the abnormal appearance.

Parents of children with congenital adrenal hyperplasia should be aware of the side effects of steroid therapy. Report signs of infection and stress to your health care provider because the child may need more medication. Steroid medications cannot be stopped suddenly, because it may lead to adrenal insufficiency. (White PC. Congenital Adrenal Hyperplasia and related disorders. In: Kliegman RM, Behrman RE, Jenson HB, Stanton BF. Nelson Textbook of Pediatrics. 18th ed. Philadelphia, Pa: Saunders Elsevier; 2007: chapter 577.)

Phenylketonuria

Phenylketonuria is a rare condition in which the body cannot properly use one of the building blocks of protein called phenylalanine that with excessive accumulation may lead to brain damage. (Harrow, CM, 2011)

At least 1 baby in 25,000 is born with PKU in the United States. The disorder occurs in all ethnic groups, although it is more common in individuals of Northern European and Native American ancestry than in those of African-American, Hispanic and Asian ancestry. (March of Dimes, 2007)

Amino acids are the building blocks for protein, but too much phenylalanine can cause a variety of health problems. People with phenylketonuria (PKU) — babies, children and adults — need to follow a diet that limits phenylalanine, which is found mostly in high-protein foods.  Babies in the United States and many other countries are screened for phenylketonuria soon after birth. Although phenylketonuria is rare, recognizing phenylketonuria right away can help prevent serious health problems. Newborns with phenylketonuria initially don't have any symptoms. Without treatment, though, babies usually develop signs of PKU within a few months. Phenylketonuria symptoms can be mild or severe and may include mental retardation, behavioral or social problems, seizures, tremors or jerking movements in the arms and legs, hyperactivity, stunted growth, skin rashes (eczema), small head size (microcephaly), musty odor in the child's breath, skin or urine, caused by too much phenylalanine in the body, fair skin and blue eyes, because phenylalanine cannot transform into melanin — the pigment responsible for hair and skin tone. A woman who has PKU and becomes pregnant is at risk of another form of the condition called maternal PKU. Many people with PKU used to stop following a low-phenylalanine diet during their teen years, as was directed by doctors at the time. But, doctors now know that if a woman doesn't follow the diet during pregnancy, blood phenylalanine levels can become very high and harm the developing fetus. Because of this, and other reasons, doctors recommend that anyone with PKU follow the low-phenylalanine diet for life. (Mayo Clinic staff, 2009)

 

  

Glucose 6- Phosphate Dehydrogenase Deficiency

Glucose 6-phosphate dehydrogenase deficiency the most prevalent illness recorded by the Department of Health (DOH) is a deficiency where the body lacks the enzyme G6PD. Babies with this deficiency may have haemolytic anemia resulting from exposure to oxidative substances found in drugs, foods and chemicals. (Harrow, CM, 2011)

G6PD deficiency is the most common known enzyme deficiency in humans. An estimated 400 million people around the world are affected. In the Philippines, around 1 in 50 children are G6PD deficient. G6PD deficiency is more common in boys than in girls. There is no known cure for G6PD deficiency. It is a lifelong condition that cannot be outgrown. However, a child with G6PD deficiency can live an active, healthy and normal life as long as he is able to avoid the substances that can trigger G6PD deficiency symptoms. If your child is G6PD deficient, he will have no symptoms unless he is exposed to one of the harmful substances that can trigger the breakdown of red blood cells. Your child's symptoms will depend on what the harmful substance was and how much of it he was exposed to. In milder cases, your child may not even show any symptoms.  In more serious cases, hemolysis (or hemolytic anemia) the accelerated destruction of red blood cells may happen. If so, he may have these symptoms such as pale skin (among darker skinned children, check the lips and tongue for paleness), fatigue, shortness of breath, rapid heart rate, jaundice (yellowing of skin and eyes) especially among newborns and dark, tea-colored urine. If your child is showing these symptoms, take him to the nearest hospital Emergency Room immediately. He may need hospitalization and medical care. When the trigger has been removed or treated, the symptoms usually resolve themselves within a few weeks. (Baby Center, 2011)

Congenital Hypothyroidism

 Congenital hypothyroidism results from the lack or absence of thyroid hormones essential for the physical and mental development of a child. If not treated at an early stage or within two weeks, the baby may suffer from growth and mental retardation. (Harrow, 2011)

From June 1996 to June 1998, a total of 62,841 newborn infants were screened for congenital hypothyroidism with thyroid stimulating hormone assay as a primary test. The method used was an immunofluorescent assay using the DELFIA TSH Kit on dried blood specimens collected by heel prick on filter paper. All infants with TSH values greater than 20microU/ml were retested. If the results remained abnormally high, confirmatory testing was done by radioimmunoassay. All infants who were confirmed to be hypothyroid were referred to pediatric endocrinologists for initial management. The overall weighted incidence of congenital hypothyroidism obtained in this study was 0.000277 (95% CI; 0.000122 - 0.000432) or 1:3,610 which may be higher than that reported by most screening programs worldwide. The recall rate was 0.16%. The higher recall rate may be explained by early testing in a number of cases and by the possibility of iodine deficiency in some of the mothers. (Fagela-Domingo C. et.al, 1999)

Galactosemia

Galactosemia is a condition in which babies are unable to process galactose, the sugar present in milk. If not treated, accumulation of excessive galactose in the body can cause problems such as liver and brain damage and cataract. (Harrow, 2011)

To determine the incidence of galactosemia (GAL) in the Philippines and to determine whether newborn screening for GAL is cost-beneficial from a societal perspective, cost-benefit analysis was performed. Newborn screening for GAL was done after the 24th hour of life using the Beutler test however it is ideally done on the 48-72 hours after birth to detect all the metabolic conditions/disorders such as Congenital Hypothyroidism, Congenital Adrenal Hyperplasia, Galactosemia, Phenylketonuria and Glucose 6-Phosphate Dehydrogenase Deficiency. Patients screened positive were recalled for confirmatory testing. Using incidence rates obtained from the different participating hospitals of the Philippine Newborn Screening Program (PNSP), the costs for the detection and treatment of GAL were compared to the expected benefits by preventing mental retardation, cataracts and other physical disabilities caused by the disorder that would lead to a loss of productivity for the individual. Sensitivity analyses for incidence and discount rates were also included. Of the 157,186 newborns screened by the PNSP since its inception in 1996, 8 screened positive results. Confirmatory testing of these patients showed that 2 had galactosemia. The incidence of galactosemia in this population therefore, is 1 in 106,006 (95% CI= 1:44,218 - 1:266,796). Projecting the figures to the actual birth rate (1.5M newborns/year), the total costs of the screening program amounted to $1.1M, while the total benefits amounted only to $0.2M, yielding net cost of $0.9M. A cost-benefit analysis of the screening program for galactosemia using the incidence 1 in 106,006 demonstrated that the costs of the program outweigh the benefits. The true incidence of galactosemia in the Philippine population may yield an incidence rate that will result in greater net benefits for the program. (Padilla et.al, 2003)