|Year : 2021 | Volume
| Issue : 2 | Page : 314-316
Primary carnitine deficiency in a neonate
Manish Rasania, Naveed Majid Ahmed, Bhatt Vivek Prafulchandra, Shashank Jain
Department of Pediatrics, Smt. B. K. S. Medical Institute and Research Center, Sumandeep Vidhyapeeth Deemed to be University, Vadodara, Gujarat, India
|Date of Submission||12-Jul-2021|
|Date of Decision||12-Sep-2021|
|Date of Acceptance||14-Sep-2021|
|Date of Web Publication||29-Dec-2021|
Dr. Naveed Majid Ahmed
Department of Pediatrics, Smt. B. K. S. Medical Institute and Research Center, Sumandeep Vidyapeeth Deemed to be University, Vadodara, Gujarat
Source of Support: None, Conflict of Interest: None
Carnitine deficiency in paediatrics can present in infants with episodes of irritability, lethargy and hepatomegaly. The main treatment for primary carnitine deficiency is to take L-carnitine supplements. Here we report a case of a female neonate with carnitine deficiency. A female child of 1.5 kg of 34 weeks of gestation was admitted for low birth weight .Baby was discharged on 18th day of life. On 25thday of life, parents brought the patient back with complains of lethargy, where hypoglycemia was detected. After recovery, baby was shifted to full feed. Metabolic disorder was suspected. Extended neonatal screening test was sent and was suggestive of decreased levels of free carnitine in blood. For treatment, syrup L-carnitine was started. Signs and symptoms of primary carnitine deficiency typically appear during infancy or early childhood. Infants mostly present with hypoglycaemia. For treatment, carnitine supplements are provided
Keywords: Creatine kinase, hypoglycemia, primary carnitine deficiency
|How to cite this article:|
Rasania M, Ahmed NM, Prafulchandra BV, Jain S. Primary carnitine deficiency in a neonate. Arch Med Health Sci 2021;9:314-6
| Introduction|| |
Carnitine is an amino acid derivative which plays a critical role in energy production. It transports long-chain fatty acids into the mitochondria so they can be oxidized (“burned”) to produce energy. In support of energy metabolism, it also participates in removing products of metabolism from cells. Primary carnitine deficiency is a rare condition caused by an abnormal gene. There is a deficiency in organic cation transporter type 2 (OCTN2), encoded by the SLC22A5 gene on chromosome 5q31,, resulting in low serum carnitine levels and decreased carnitine accumulation inside cells. Carnitine deficiency causes defective fatty acid oxidation and utilization for energy production. When fatty acids cannot be used, glucose is consumed without regeneration via gluconeogenesis, resulting in hypoglycemia., Drugs such as cyclosporine and valproate can also cause carnitine deficiency, renal tubular dysfunction, and malnutrition, and complete parenteral nutrition may also result in secondary carnitine deficiency. In some cases, the condition only leads to low carnitine levels in muscle. This is called primary muscle carnitine deficiency. If the liver and heart are also affected, it may be called systemic carnitine deficiency. It is also called carnitine uptake defect. It is basically a metabolic state in which carnitine concentrations in plasma and tissues are less than the levels required for the normal function of the organism. Biologic effects of low carnitine levels may not be clinically significant until they reach <10%–20% of normal.
Secondary carnitine deficiency is a more common condition. In this case, there is not a problem getting carnitine into cells. Instead, the problem is that there is not enough carnitine in the blood. It can result from certain disorders (such as chronic renal failure) or under particular conditions. Carnitine deficiency in pediatrics can present in two ways. Infants with the infantile metabolic (hepatic) type present in the first 2 years of life with episodes of irritability, tiredness, and abnormal enlargement of the liver (hepatomegaly). Laboratory results show hypoglycemia with little to no ketones in the urine (hypoketotichypoglycemia), high levels of ammonia in the blood (hyperammonemia), and elevated liver transaminases. Some children with infantile presentation may also have symptoms of muscle disease.
Children with the childhood myopathic (cardiac) type usually present between ages 2 and 4 with heart disease (cardiomyopathy), low muscle tone (hypotonia), skeletal muscle weakness, and elevated serum creatine kinase. Carnitine deficiency has a better prognosis if it is diagnosed and treated early; however, a high level of clinical suspicion is required for its timely and accurate diagnosis. The main treatment for primary carnitine deficiency is to take L-carnitine supplements. Here, we report a novel case of a female neonate with carnitine deficiency.
| Case Report|| |
A female child weighing 1.5 kg of 34 weeks of gestation born to a mother with pregnancy-induced hypertension was admitted to the neonatal intensive care unit for low birth weight, prematurity, and respiratory distress. For treatment, oxygen and antibiotics were started. After successful weight gain, the baby was discharged on the 18th day of life. On the 25th day of life, parents brought the patient back with complaints of lethargy, where low random blood sugar (RBS) was detected. On the 32nd day of life, baby had two episodes of significant apnea and 1 episode of vomiting. On examination, hypothermia, hypotonia, and delayed capillary refill time were noted. RBS was 23 mg/dl at that point. For treatment, the baby was given a bolus of dextrose 10 injection, along with multiple electrolytes. The GDR was set at 8, and gradually increased to 10 then 12. Baby was also put on inotropes and antibiotics. After recovery, baby was shifted to full feed. Since no other signs of sepsis were noted apart from lethargy, with septic screen and blood culture negative, and since the baby had refractory hypoglycemia, metabolic disorder was suspected.
Extended neonatal screening test was sent and was suggestive of decreased levels of free carnitine in blood [Table 1].
For treatment, syrup L-carnitine was started at 100 mg/kg/day thrice daily. The patient was subsequently discharged.
| Discussion|| |
Primary carnitine deficiency is inherited in an autosomal recessive pattern.
Carriers of SLC22A5 gene mutations may have some signs and symptoms related to the condition. The incidence of primary carnitine deficiency in the general population is approximately 1 in 120,000 newborns. In Japan, this disorder affects 1 in every 40,000 newborns. Mutations in the SLC22A5 gene cause primary carnitine deficiency. This gene provides instructions for making a protein called OCTN2 that transports carnitine into cells.
Signs and symptoms of primary carnitine deficiency typically appear during infancy or early childhood and can include severe brain dysfunction (encephalopathy), a weakened and enlarged heart (cardiomyopathy), confusion, vomiting, muscle weakness, and low blood sugar (hypoglycemia), often associated with hepatomegaly, elevated transaminase levels, hyperammonemia, pericardial effusion and recurrent attacks of abdominal pain and diarrhea. Metabolic disorders accompanied by altered carnitine biosynthesis have been linked to neurodevelopmental disorders, such as autism spectrum disorder. Infants mostly present with hypoglycemia. In one of the cases, developmental delay and ID associated with PCD has only been reported once before. Therefore, we suggest that testing for plasma carnitine levels might be considered in the differential diagnosis of child developmental delays. Thus, PCD should also be included in the framework of possible genetic causes of developmental delay and IDs. There have been cases that showed dilated cardiomyopathy and atypical manifestations including the history of anemia, frequent respiratory distress, and proximal muscle weakness.
In neonates, carnitine palmitoyltransferase deficiency is diagnosed using mass spectrometry to screen blood. Prenatal diagnosis may be possible using amniotic villous cells. Confirmation test is done by transported assay in fibroblast or SLC22A5 gene study. For treatment, carnitine supplements are provided after which there is significant recovery. The prognosis for individuals with Systemic primary carnitine deficiency (CDSP) depends on the age, presentation, and severity of symptoms at the time of diagnosis. The infantile metabolic and childhood myopathic presentations of CDSP can be fatal if not treated early.
Overall prognosis is good provided yearly aspartate transaminase, alanine transaminase, electrocardiogram RBS is done.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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