Inborn Errors of Metabolism (IEM) are a group of rare genetic disorders that can have severe consequences if left undetected and untreated. These disorders result from deficiencies or defects in enzymes responsible for metabolising specific substances in the body, leading to the accumulation of toxic metabolites. If not identified early and managed promptly, IEM can cause significant long term physical problems and damage to the brain, sometimes even posing a dangerous and potentially fatal threat.
Early detection of IEM is paramount to preventing the development of debilitating health issues in affected individuals. During the newborn screening process, blood tests can detect several types of IEM, allowing for timely intervention and the initiation of appropriate treatment plans.
Newborn screening has proven to be a life-saving measure, as many IEM conditions can present with subtle or nonspecific symptoms during the first few weeks of life.
continued below
NBS is a successful program in many developed countries. In India, in 2018 the Indian Council of Medical Research (ICMR) task force had recommended NBS as a means to prevent intellectual disability, morbidity and early death in children.
The Indian Society for Paediatric and Adolescent Endocrinology has also published clinical practice guidelines for NBS, diagnosis and the management of certain metabolic diseases.
Children with IEMs have a wide spectrum of clinical presentations from appearing physically normal to having distinctive dysmorphic physical features. While majority of them appear physically normal at birth, many can present with significant non-specific signs and symptoms common to other serious medical conditions.
IEM Disorders:
IEM can lead to a range of physical problems, depending on the specific metabolic pathway affected. Some IEM conditions impact the body’s ability to break down proteins, fats, or carbohydrates, resulting in the accumulation of toxic substances. There are many different types of inborn errors of metabolism. A few of them are:
- G6pd
- Galactosemia
- Phenylketonuria (PKU)
- Biotinidase
- Cystic fibrosis
- Thyroid and adrenal hyperplasia
Glucose-6-phosphate dehydrogenase (G6PD) functions throughout the body, but its deficiency is seen predominantly in its effects on the red blood cells. G6PD deficiency can result in neonatal jaundice and in life threatening reactions to several medications, foods, and infections.
Phenylketonuria (PKU) is an IEM that interferes with the breakdown of the amino acid phenylalanine, leading to its accumulation in the bloodstream. Elevated phenylalanine levels can cause severe neurological damage and intellectual disabilities if not controlled through dietary modifications.
Similarly, disorders like maple syrup urine disease (MSUD) and galactosemia can cause life-threatening complications if not managed promptly. Galactosemia disrupts the processing of galactose, a sugar found in milk, which can lead to liver and kidney damage, cataracts, and intellectual disabilities.
Biotinidase deficiency is an inherited disorder in which the body is unable to recycle the vitamin biotin. It prevents the body from processing proteins, fats, and carbohydrates correctly. If this condition is not recognised and treated, its signs and symptoms typically appear within the first few months of life. The more severe form of the condition can cause seizures, weak muscle tone (hypotonia), breathing problems, hearing and vision loss, problems with movement and balance (ataxia), skin rashes, hair loss (alopecia), and a fungal infection called candidiasis.
Cystic fibrosis is an inherited condition that causes sticky mucus to build up in the lungs and digestive system. This causes lung infections and problems with digesting food. The babies can also develop several related conditions, including diabetes, thin, weakened bones (osteoporosis), infertility in males, and liver problems.
Two disorders, congenital adrenal hyperplasia (CAH) and congenital hypothyroidism (CH), when untreated, can lead to devastating, irreversible and fatal outcomes. Congenital adrenal hyperplasia is an inherited disorder that affects the production of certain hormones and causes the adrenal glands to become too big. Permanent cognitive impairment, growth failure and dysmorphic features are seen in congenital hypothyroidism.
Newborn screening (NBS) allows early diagnosis and treatment of these disorders, ensuring excellent prognosis.
Protecting Cognitive Function
The brain is particularly vulnerable to the effects of IEM, and early diagnosis is crucial to prevent cognitive impairments and developmental delays. If untreated, IEM can cause irreversible damage to the brain during critical stages of growth and development. Children born with certain metabolic disorders may experience intellectual disabilities, seizures, motor difficulties, and behavioural issues as a result of brain damage.
Timely Intervention and Treatment
When IEM is identified in the early stages, healthcare providers can implement immediate interventions tailored to each specific condition. Management often involves strict dietary modifications, enzyme replacement therapy, or specific medications to control the accumulation of toxic metabolites. These interventions can help prevent or minimise physical complications and cognitive impairments.
Conclusion
The detection of Inborn Errors of Metabolism is of utmost importance to safeguard the health and well-being of affected individuals. Early diagnosis through newborn screening empowers healthcare providers to implement timely interventions, preventing physical problems and protecting cognitive function. By raising awareness about the critical nature of early detection, we can strive to provide better care and improve the outcomes for those living with IEM.
By Dr Gautam Wankhede, Director, Medical Affairs, Mylab Discovery Solutions
(DISCLAIMER: The views expressed are solely of the author and ETHealthworld.com does not necessarily subscribe to it. ETHealthworld.com shall not be responsible for any damage caused to any person/organisation directly or indirectly).
Most Read in Industry
Join the community of 2M+ industry professionals
Subscribe to our newsletter to get latest insights & analysis.
Download ETHealthworld App
- Get Realtime updates
- Save your favourite articles
