When Ayden Mookken was born in January 2005 in a private hospital in the US, he looked a normal healthy baby. Yet, in a routine screening, just 24 hours after birth, he tested positive for an inborn error of metabolism (IEM) called G6PD (or Glucose-6-phosphate deficiency) which, if undetected, could prove fatal in some cases. Immediately, young Ayden was put on a very simple treatment—avoidance therapy. The doctors advised Ayden’s mother to keep him away from sulpha-based drugs and certain foods, such as beans. “We were lucky that the hospital, where he was born, ran a mandatory newborn screening procedure,” says Ayden’s father Thomas Mookken, who returned to India to launch NeoGen Labs in Bangalore, a specialized laboratory that offers a screening test for 50 such disorders.
IEM disorders are caused when the body is unable to break down certain naturally produced chemicals, which then accumulate in the body and turn toxic. This toxic build-up can lead to slow physical development or brain damage and, in some cases, even death. Most infants with these disorders show no obvious signs, but the build-up can be rapid enough for the condition to become irreversible within a few days of birth. In developed countries, 10 out of 1,000 infants die from IEM disorders. In India, health care professionals believe at least 100 out of 1,000 infant deaths are caused by metabolic disorders, a fifth of which could have been prevented through early detection.
Till date, screening for newborns in India has focused largely on detection of neonatal congenital hypothyroidism (where the body does not produce sufficient thyroid hormone), which occurs in one out of every 2,600 children, according to a study done by Mumbai’s KEM Hospital. The hospital tracked more than 24 million babies born between 1978 and 2004, and also concluded that G6PD occurred in one out of every 70 babies born in India. “In Indian conditions, a combined test that checks for five of the most prevalent disorders should be mandatory,” says Vasanth Shetty, a Bangalore-based paediatrician, who compulsorily tests his patients for neonatal hypothyroidism. The other four tests he recommends are for congenital adrenal hyperplasia, that leads to a change in female genitalia unless detected at birth, G6PD, that is most commonly found amongst the Parsi population, Phenylketonuria (a genetic disorder in which the body is not able to utilize the essential amino acid, phenylalanine) and galactosemia (another genetic disorder in which the body is not able to metabolize the sugar galactose).
Currently, a simple heel prick that yields up to four-five drops of a newborn’s blood is placed on a dry filter paper and transported to laboratories that run tests on a Tandem Mass Spectrometer. At laboratories such as NeoGen, this procedure can detect an additional 45 disorders that include improper metabolism of fatty acids, organic acid and amino acids.
“Apart from special diets in some cases, the treatment can be as simple as a spoonful of sugar before a baby goes to sleep at night,” says Rohit Cariappa, chief scientist, NeoGen Labs, who believes that all IEM disorders, with a clearly-defined treatment option, must be tested for. Dr Lal Path Labs, a Delhi-based pathology unit, also offers a newborn screening option that tests for 44 disorders; at the Bangalore-based neonatal hospital Cradle, blood samples of newborns whose parents have opted for IEM testing are shipped to the Australian NeoNatal Screening Centre in Adelaide.
Typically, children who have IEM disorders do not necessarily have a family history of such illnesses, but sometimes, the parents can be silent carriers. For instance, at Delhi-based Fortis La Femme, a newborn tested positive for an IEM disorder that proved fatal but as the cause of death was detected early, doctors were able to counsel the parents on precautions when planning a second child. “In such cases, we can offer antenatal procedures such as genetic probes that can detect if a foetus is carrying the same disorder,” says Raghuram Mallaiah, senior consultant neonatologist.
At present, IEM testing at private laboratories costs an average of Rs4,000 for a child where tests are conducted for an average of 45–50 disorders. Some doctors feel this makes the test too expensive to be introduced on a mass scale in government hospitals, where it is urgently required. “If newborn screening is to become a state-sponsored mandatory procedure, we need to develop a standard panel of two-three disorders costing not more than Rs200 per test. Only then will it be accepted as a preventive health care option similar to immunization,” says Mamta Muranjan, associate professor, genetic clinic and department of paediatrics, Seth GS Medical College and KEM Hospital in Mumbai.
But for parents such as the Mookkens, who are relieved that the disorder was detected early enough to be treated in their infant, the efficacy of testing newborns for IEM disorders can never be doubted.