<P> Acute episodes due to SPCD are often preceded by metabolic stress such as extended fasting, infections or vomiting . Cardiomyopathy can develop in the absence of an acute episode, and can result in death . SPCD leads to increased carnitine excretion in the urine and low levels in plasma . In most locations with expanded newborn screening, SPCD can be identified and treated shortly after birth . Treatment with high doses of carnitine supplementation is effective, but needs to be rigorously maintained for life . </P> <P> SPCD is more common in the Faroe Islands than in other countries, at least one out of every 1000 inhabitants of the Faroes has the illness, while the numbers for other countries are one in every 100,000 . Around 100 persons in the islands have been diagnosed, around one third of the whole population of 48,000 people have been screened for SPCD . Several young Faroese people and children have died a sudden death with cardiac arrest because of SPCD . Scientists believe that around 10% of the Faroese population are carriers of the gene for SPCD . These people are not ill, but may have a lower amount of carnitine in their blood than non-carriers . </P> <P> The presentation of patient with SPCD can be incredibly varied, from asymptomatic to lethal cardiac manifestations . Early cases were reported with liver dysfunction, muscular findings (weakness and underdevelopment), hypoketotic hypoglycemia, cardiomegaly, cardiomyopathy and marked carnitine deficiency in plasma and tissues, combined with increased excretion in urine . Patients who present clinically with SPCD fall into two categories, a metabolic presentation with hypoglycemia and a cardiac presentation characterized by cardiomyopathy . Muscle weakness can be found with either presentation . </P> <P> In countries with expanded newborn screening, SPCD can be identified shortly after birth . Affected infants show low levels of free carnitine and all other acylcarnitine species by tandem mass spectrometry . Not all infants with low free carnitine are affected with SPCD . Some may have carnitine deficiency secondary to another metabolic condition or due to maternal carnitine deficiency . Proper follow - up of newborn screening results for low free carnitine includes studies of the mother to determine whether her carnitine deficiency is due to SPCD or secondary to a metabolic disease or diet . Maternal cases of SPCD have been identified at a higher than expected rate, often in women who are asymptomatic . Some mothers have also been identified through newborn screening with cardiomyopathy that had not been previously diagnosed . The identification and treatment of these asymptomatic individuals is still developing, as it is not clear whether they require the same levels of intervention as patients identified with SPCD early in life based on clinical presentation . </P>

Carnitine deficiency due to inborn errors of metabolism