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Metabolic Genetics Clinic

My newborn received an abnormal screen. What do I do?

newborn test

At the Metabolic Genetics Clinic, we specialize in the diagnosis and treatment of children and adults with inherited metabolic disorders, also known as “inborn errors of metabolism.” 

Metabolism refers to all the chemical reactions that take place in our body to break down food to make proteins and other molecules. Our bodies use these proteins and molecules to function, release energy and convert excess nitrogen into waste products excreted in urine. Metabolic diseases occur when these chemical processes are interrupted, and are often due to enzyme deficiencies caused by errors in single genes. There are hundreds of inherited metabolic diseases. Most people with metabolic diseases begin experiencing symptoms in the newborn period or childhood, but in some, the disease becomes apparent in adulthood. 

Many metabolic diseases are treatable. Early diagnosis and treatment may prevent permanent organ damage and death. Treatments vary based on the specific disease and often involve modification of diet and supplementation with specific medications, as well as preemptive inpatient care during infections. Other therapies include enzyme replacement therapy, hematopoietic stem cell transplantation, and organ transplantation.

In the Metabolic Genetics Clinic, we evaluate patients with a variety of symptoms, including:

  • Abnormal newborn screen
  • Recurrent unexplained illness with dehydration and acidosis
  • Recurrent hypoglycemia
  • Altered mental status
  • Liver disease
  • Feeding intolerance, recurrent vomiting
  • Failure to thrive, growth retardation
  • Developmental delay, intellectual disability
  • Hypotonia
  • Progressive deterioration of neurologic function        
  • Epilepsy
  • Muscle weakness, muscle breakdown
  • Cardiomyopathy

We diagnose and treat patients who have a wide range of metabolic conditions including:

  • Carbohydrate disorders
    • Galactosemia, hereditary fructose intolerance, glycogen storage diseases
  • Amino acid disorders
    • Phenylketonuria, tyrosinemia, homocystinuria, maple syrup urine disease
  • Fatty acid oxidation defects
    • Medium and long chain fatty acid oxidation defects (MCADD, LCHADD, VLCADD), carnitine disorders
  • Organic acidemias
    • Methylmalonic acidemia, propionic acidemia, biotinidase deficiency, glutaric acidurias, isovaleric academia, vitamin B12 metabolism disorders
  • Urea cycle disorders
    • Ornithine transcarbamylase deficiency, citrullinemia, argininosuccinic aciduria and others
  • Mitochondrial diseases
    • MELAS, MERRF, NARP, Leigh disease, Barth syndrome and others
  • Peroxisomal disorders 
    • X-linked Adrenoleukodystrophy, Zellweger spectrum disorders, Refsum disease and others
  • Lysosomal storage disorders
    • Gaucher disease, Fabry disease, mucopolysaccharidoses, Pompe disease and others

Our Team

Our team consists of five geneticists specialized in metabolic disorders, two genetic counselors, a nurse manager, a metabolic dietitian and a clinic coordinator. Our outpatient Metabolic Genetics Clinic runs three days a week. To ensure timely and accurate diagnosis, we work closely with the Biochemical Genetics Laboratory at the Kennedy Krieger Institute. Our on-call team of metabolic doctors is available to our patients and families 24 hours a day, seven days a week. When our pediatric metabolic patients need inpatient hospital care, we admit them to Johns Hopkins Children’s Center under our own Metabolic Inpatient Service and serve as their primary inpatient caregiver team. When our adult metabolic patients need inpatient hospital care, we consult closely with the medical, surgical, gynecologic-obstetric or neurologic teams that are managing their care.