Carnitine-acylcarnitine translocase deficiency

Georgianne Arnold MD

Neurogenetic Disorders

Updated 09.28.2023
Released 11.28.1994
Expires For CME 09.28.2026

Carnitine-acylcarnitine translocase deficiency

Author: Georgianne Arnold MD

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Editor: Deepa S Rajan MD

Carnitine-acylcarnitine translocase deficiency

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Introduction

Overview

Carnitine-acylcarnitine translocase deficiency is a rare inborn error of energy metabolism involving the carnitine cycle and long-chain fatty acid oxidation. This enzyme deficiency is considered the most severe disorder of fatty acid oxidation. Its clinical features are related to the impairment of fasting adaptation and cardiac and skeletal muscle metabolism, and its presentation overlaps with the clinical presentation of the severe neonatal form of carnitine palmitoyltransferase type 2 deficiency. In this article, the author describes the developments of this disorder, including the expanding clinical phenotype, management, and advances in the understanding of the genetics of this condition since the human gene was cloned in 1997.

Key points

	• Carnitine-acylcarnitine translocase deficiency shares clinical features with other defects of long-chain fatty acid oxidation.
	• The biochemical findings may be indistinguishable from the neonatal form of carnitine palmitoyltransferase type 2 deficiency.
	• The mortality rate is high, and it occurs mainly in the first year of life.
	• In at least a quarter of cases, patients show a mild presentation with long-term survival.
	• Treatment consists of low-fat/high-carbohydrate diet and medium chain fat supplementation with frequent meals and avoidance of fasting.

Historical note and terminology

Carnitine-acylcarnitine translocase (CACT) deficiency is a rare defect in mitochondrial long-chain fatty acid oxidation and was first described in 1992 (18). Fatty acid oxidation is a critical energy source during fasting, and defects commonly result in life-threatening energy deficiency. The process of long chain fatty acid oxidation requires esterifying the fatty acid to coenzyme A (forming an acylCoA), then exchanging the CoA for carnitine (forming an acylcarnitine), after which the enzyme carnitine-acylcarnitine translocase transports the acylcarnitine into the mitochondria where oxidation and energy production occur. There are approximately a dozen defects in long-chain fat metabolism, and they share similar clinical features related to their impairment of fasting, cardiac functioning, and skeletal muscle metabolism (20).

This disorder is rare, with only about 100 cases reported. The majority of patients become symptomatic in the newborn period. The mortality rate reaches up to 65% of patients in the first year of life due to cardiac complications (12). However, some patients have been described with later onset (02) or a milder phenotype and long-term survival (19). Evidence suggests that survival may be possible, even in some severe cases (16).

Clinical manifestations

Presentation and course

Metabolic decompensation occurs during periods of catabolism when fatty acid oxidation provides crucial energy. Most frequently, the first episode of metabolic decompensation occurs within the first hours to days of life because this is a period of metabolic adaptation when lipids are an essential metabolic fuel and can recur during later episodes of fasting or infection. The organs most affected are those that depend strongly on energy from fat oxidation, particularly heart, muscle, and liver (19). Classic features include hypoketotic hypoglycemia, cardiomyopathy, cardiac dysrhythmias, hyperammonemia, liver dysfunction, and skeletal muscle damage. Less specific features commonly include variable degrees of encephalopathy ranging from lethargy to coma, poor feeding, hypotonia, seizures, hypothermia, pallor, respiratory distress, and cardiorespiratory collapse. This presentation is strongly suggestive of a disorder of long-chain fatty acid oxidation and is not unique to carnitine-acylcarnitine translocase deficiency, but carnitine-acylcarnitine translocase deficiency and carnitine palmitoyltransferase type 2 deficiency in particular should be suspected when onset occurs in the first hours of life (24). There may be history of a sibling who died suddenly in the neonatal period or in early infancy. Metabolic testing typically reveals low levels of free carnitine and elevated long-chain acylcarnitine esters. Variable and transient dicarboxylic aciduria may also be present.

Prognosis and complications

After the initial acute episode of metabolic decompensation, patients are placed on a low-fat/high-carbohydrate diet supplemented with medium chain triglycerides (which do not require carnitine to enter the mitochondria), frequent meals, and avoidance of fasting. Although the patients who survive the initial decompensation can improve, they are highly vulnerable to fasting or illness that can lead to acute metabolic decompensation with the subsequent risk of a permanent neurologic impairment or sudden death.

Despite treatment, the outcome may be poor, and patients continue to have recurrent episodes of deterioration precipitated by fasting or by intercurrent febrile illnesses (13). In between episodes, the infants are often normal, though they may show muscle hypotonia, cardiac hypertrophy/cardiomyopathy, chronic liver dysfunction, and hyperammonemia. Approximately 65% of the patients reported died within the first year of life. The main cause of death is cardiomyopathy or lethal arrhythmia, often occurring in the setting of an intercurrent febrile illness. Sudden death may also occur.

It is generally accepted that the accumulating experience in diagnosis and management of these disorders, the timelier diagnosis, and the institution of better acute and chronic medical treatment has contributed to the increasing number of patients with milder phenotypes and longer-term survival. In a review, outcome seemed to correlate better with the absence of cardiac disease and higher long-chain fatty acid oxidation rate in cultured fibroblasts than with residual enzyme activity (22).

Clinical heterogeneity is also becoming more evident. An exceptional case with a hepatocerebral form resembling mitochondrial depletion syndrome has been described (24), another patient with dysplastic brain lesions (07), and another with retinal changes have been reported (22).

Clinical vignette

A male newborn appeared well at delivery. He had an acute life-threatening event at 36 hours of age with a brief seizure and cardiorespiratory collapse. The collapse was thought to be triggered by fasting stress associated with the initiation of breast-feeding. The infant had hypoglycemia and hyperammonemia up to 400 µmol/L. Following resuscitation with intravenous fluids and glucose, the infant had premature ventricular contractions and ventricular tachycardia for several days. Physical examination was normal, although moderate hepatomegaly was noted with later episodes. Plasma carnitine determinations showed reduced total carnitine concentrations with nearly 100% as acylcarnitines and unusually elevated long-chain acylcarnitine levels.

During the 3 years that the child survived, he had recurrent episodes of hypoketotic hypoglycemic coma when fasting for greater than 10 to 12 hours. Plasma ammonia remained slightly elevated. Mental development appeared to be normal, but he had chronic generalized muscle weakness that limited walking to a few steps. When otherwise well, echocardiography revealed no evidence of cardiomyopathy. He was managed with continuous nasogastric tube feedings in order to limit exposure to fasting and because he had gastroesophageal reflux. Ultimately, the child died of progressive liver failure combined with increasing weakness and respiratory insufficiency (18).

Biological basis

Etiology and pathogenesis

The basis for this disease is deficient activity of the mitochondrial inner membrane carrier protein, carnitine-acylcarnitine translocase (CACT). Studies have provided more detail on the in silico membrane dynamics (15).

Carnitine-acylcarnitine translocase is a component of the carnitine shuttle system. Mitochondrial fatty acid oxidation provides crucial energy during fasting, and there are separate enzymes for metabolism of short chain (4 to 5 carbon), medium chain (6 to 10 carbon) and long chain (12 to 18 carbon) fats. Although short and medium chain length fatty acids can penetrate the mitochondria directly, long chain fatty acids required a shuttle system to enter the mitochondria.

The carnitine shuttle system consists of a series of four steps: 1) the long chain fatty acid is “activated” by esterification to coenzyme A, creating a long chain fatty acylCoA; 2) the enzyme carnitine palmitoyl transferase 1 (CPT1) exchanges the CoA for carnitine, creating an acylcarnitine, which can cross the outer mitochondrial membrane; 3) the enzyme carnitine-acylcarnitine translocase (CACT) transports (translocates) the acylcarnitine across the inner mitochondrial membrane (and discharges a free carnitine back into the cytoplasm); and 4) the enzyme carnitine palmitoyl transferase 2 (CPT2) exchanges the carnitine for a coenzyme A, at which point oxidation of the long chain fat can commence (19). For a detailed description of the carnitine shuttle system, more information can be found in the article published by Stanley and colleagues (19).

Mitochondrial oxidation of fatty acids provides an essential source of energy for the heart, for exercising skeletal muscle, and during long-term fasting (longer than 15 to 20 hours in infants; longer than 24 to 36 hours in adults) (17). Fatty acids are the preferred substrate for the heart. They provide more than 60% of the energy consumed by muscle working aerobically. In late stages of fasting, fatty acid oxidation accounts for over 80% of oxygen consumption. Thus, cardiomyopathy, arrhythmias, and cardiovascular collapse are common in infants with severe carnitine-acylcarnitine translocase deficiency, often within the first days of life. The end products of hepatic fatty acid oxidation are the ketones, beta-hydroxybutyrate and acetoacetate, which are exported to be used by the brain and other organs. Because the long-chain fatty acids do not cross the blood-brain barrier, hepatic ketogenesis serves an essential function in permitting the brain to indirectly use body fat stores and, thus, spare glucose consumption.

The acute clinical manifestations in patients with the carnitine-acylcarnitine translocase deficiency reflect the disruption of fasting adaptation caused by a very severe block in the fatty acid oxidation pathway (18). Unfortunately, failure of fatty acid oxidation has secondary effects on other metabolic processes. In particular, fatty acid oxidation provides the energy needed to initiate gluconeogenesis at a time when glucose utilization is increased, thus, hypoketotic hypoglycemia ensues, worsening the energy crisis. The presentation can mimic Reye syndrome, with acute disruption of liver function including elevated serum transaminases, hyperuricemia, and impaired synthesis of clotting factors; there is also a direct inhibition of the urea cycle leading to hyperammonemia (19). The failure of fuel supply for the brain leads to lethargy, coma, or seizures and may result in permanent brain injury. The illness induced by fasting can be associated with acute cardiac failure or dysrhythmias and acute evidence of skeletal muscle weakness or rhabdomyolysis. It is likely that the accumulation of long-chain acylcarnitines contributes to poor myocardial function and inhibits ATP formation (19).

Chronic effects of impaired fatty acid oxidation are more prominent in the reported cases of carnitine-acylcarnitine translocase deficiency compared to most of the other inborn errors of mitochondrial fatty acid oxidation. As in the acute presentations, the organs most affected tend to be those most dependent on fatty acid oxidation, mostly heart, skeletal muscle, and liver (19). Skeletal weakness, persistent liver dysfunction with hyperammonemia and progressive liver failure, and cardiomyopathies and dysrhythmias have been noted (18).

The physical examination is typically nonspecific. Patients with genetic defects in fatty acid oxidation may show increased neutral fat deposits in liver or skeletal muscle, and transient hepatomegaly can be seen. In several cases of carnitine-acylcarnitine translocase deficiency examined postmortem, increased fat deposits were detected in liver, heart, and kidneys, and minimal or no fatty changes were noted in skeletal muscle (03); iron deposition has been reported in the liver and heart (02).

Although milder phenotypes have been associated with higher residual enzyme activities, no clear correlation has been found between the clinical phenotype and the enzyme defect (19). Generally, the residual activity ranges from less than 1% to 7%. However, some correlation has been observed between the clinical phenotype and the impairment of fatty acid oxidation. Although severely affected patients have residual palmitate oxidation of less than 5%, milder patients have 27% (09).

Common to all of the genetic defects in mitochondrial fatty acid oxidation identified to date, carnitine-acylcarnitine translocase deficiency is inherited in an autosomal recessive fashion. Intermediate levels of translocase activity can be demonstrated in cultured fibroblasts from parents, but heterozygotes appear to be asymptomatic (18).

The cDNA encoding rat carnitine-acylcarnitine translocase deficiency was cloned in 1997 (10), and the human homolog was cloned shortly thereafter (06). The carnitine-acylcarnitine translocase deficiency gene is composed of nine exons and spans about 16.5 kb along chromosome 3p21 (08). Sequencing of the gene encoding carnitine-acylcarnitine translocase (SCL25A20) in patients with carnitine-acylcarnitine translocase deficiency has shown a heterogenous range of mutations (13). The c.199-10T>G splice site variant appears to be most common (24), whereas the c.82G>T variant common in those of Pakistani heritage appears to confer an attenuated phenotype. In Asian patients, a common mutation (IVS2-10T> G) has been detected that is thought to be a founder mutation (21; 25).

Diagnostic workup

The presence of carnitine-acylcarnitine translocase deficiency or other defects in fatty acid oxidation is most easily suspected by abnormalities found during an acute attack of illness, as abnormal metabolites associated with metabolic stress are less prominent in the convalescent state (17; 20). Suspicious findings include pervasive hypoglycemia (particularly with hypoketosis), cardiovascular collapse, or multisystemic dysfunction involving liver, heart, and muscle. Extra samples of serum or plasma and urine should be collected during the acute episode for special testing as described below.

Once a fatty acid oxidation defect is suspected, several avenues need to be pursued to determine which pathway is involved and to identify the specific site of defect. Standard metabolic testing includes plasma/urine carnitine, plasma acylcarnitine analysis (by tandem mass spectrometry), urine organic acids, plasma amino acids, ammonia, liver transaminases and other functional testing, plasma/urine ketones, blood gases, anion gap, bicarbonate, and others as indicated. The most specific findings for carnitine-acylcarnitine deficiency are most likely to be found on assays of plasma or tissue carnitine concentrations and acylcarnitine profiles, urinary organic acid profile, and the use of cultured fibroblasts or lymphoblasts to test overall fatty acid oxidation capacity and for assays of specific steps in the pathway.

Carnitine. Measurement of plasma carnitine is useful in suspected fatty acid oxidation defects because nearly all are associated with abnormal levels (18). In carnitine-acylcarnitine translocase deficiency, plasma total carnitine levels are reduced to 5 to 30 µmol/L (10% to 50% of normal, but can be within the low normal range), whereas esterified carnitine levels esters are elevated to as much as 90% of the total (normal is less than 10%), thus, the ratio of esterified to free carnitine is high (18). Before carnitine supplementation, in carnitine uptake disorders plasma carnitine will be low but urine carnitine will be high, differentiating these disorders from carnitine-acylcarnitine translocase deficiency.

Plasma acylcarnitine. Fast atom bombardment-mass spectrometry (tandem mass spectrometry) can quantify the acylcarnitines that have built up in fatty acid oxidation disorders (as well as in some other inborn errors of metabolism). In carnitine-acylcarnitine translocase deficiency (and CPT2 deficiency), the analysis usually shows increased long-chain acylcarnitines (C16, C16:1, C18:1, and C18:2). When mitochondrial beta oxidation is inadequate to meet energy needs, omega oxidation will be augmented, resulting in dicarboxylic acids, which are also detectable on acylcarnitine analysis.

Urinary organic acids. Urine organic acid analysis is generally less sensitive and specific than acylcarnitine profiles but can help to identify metabolites associated with fatty acid oxidation disorders, particularly in the acute state. It is also helpful in working through the differential diagnosis by identifying metabolites of other metabolic disorders. The limited information on carnitine-acylcarnitine translocase deficiency suggests that, at times of acute illness, the urinary organic acid profile shows only nonspecific evidence of impaired fatty acid oxidation, such as low ketones and increased medium-chain dicarboxylic acid levels (most commonly adipic, suberic and sebacic acids).

Plasma amino acid analysis. Analysis of amino acids is not helpful in the diagnosis of carnitine-acylcarnitine translocase deficiency but can be useful to rule out other disorders (for example, a urea cycle defect causing hyperammonemia).

Carnitine-acylcarnitine deficiency and carnitine palmitoyl transferase type 2 deficiency are subsequent steps in the carnitine cycle, and both result in accumulation of long-chain acylcarnitines with similar metabolic profiles. Thus, additional testing is required to confirm the diagnosis. This can include molecular analysis of the SLC25A20 or specific assay of carnitine-acylcarnitine translocase activity using cultured skin fibroblasts or lymphoblasts (19). To date, at least 36 mutations have now been identified. More information can be found on the following site:www.hgmd.org.

Prenatal diagnosis has been reported on several occasions: by in vitro beta-oxidation analysis in cultured amniocytes and in chorionic villi by assaying carnitine-acylcarnitine translocase deficiency activity in chorionic villi and by mutation analysis in amniocytes and chorionic villi.

Management

Management of carnitine-acylcarnitine translocase deficiency is aimed at providing sufficient glucose to minimize the demand for fatty acid oxidation (19). During acute episodes of illness, intravenous glucose (plus insulin, if needed) should be given at rates sufficient to suppress lipolysis and subsequent fatty acid oxidation, typically at 8 to 10 mg/kg/min for infants and children and 4 to 5 mg/kg/min for adults. Glucose infusion at these rates should be administered regardless of whether hypoglycemia is present or not, as some cases lethal metabolic crisis can occur without apparent hypoglycemia. Whenever possible, alternate energy source with medium chain triglyceride should be provided. Triheptanoin (a 7-carbon medium-chain fat) has been reported to be helpful in acute or chronic therapy (23; 12; 14; 16). The hyperammonemia is not associated with elevated glutamine levels, and response to traditional ammonia scavengers has been disappointing (16). At present, specific crisis management protocols have not been written for this rare defect, but protocols appropriate for other long chain fatty acid oxidation disorders are generally appropriate (for example, https://www.newenglandconsortium.org/vlcadd).

Long-term treatment is aimed at limiting fasting stress with frequent meals and often continuous overnight feeding. The diet, as in other long-chain fatty acid oxidation disorders, consists of a low fat/high carbohydrate diet. Long-chain fatty acids are restricted, and medium chain triglycerides and essential fatty acids are provided. Infants can be fed a formula high in medium chain triglycerides. Skimmed breast milk has been reported to be successful in the treatment of an infant with carnitine-acylcarnitine translocase deficiency (11).

Carnitine supplementation for carnitine-acylcarnitine translocase deficiency and other disorders of long-chain fatty acid oxidation is controversial. Because of evidence that long-chain acylcarnitines can have adverse effects on cardiac arrhythmias, there is reason for concern that carnitine treatment might have adverse consequences. However, carnitine supplementation has been found to increase free carnitine and acetylcarnitine formation and to decrease long-chain acylcarnitines (07). Several patients with carnitine-acylcarnitine translocase deficiency have been supplemented with carnitine and have shown a favorable course, in some instances as high as up to 200 to 300 mg/kg per day (07; 03).

References

01: Baruteau J, Sachs P, Broué P, et al. Clinical and biological features at diagnosis in mitochondrial fatty acid beta-oxidation defects: a French pediatric study from 187 patients. Complementary data. J Inherit Metab Dis 2014;37(1):137-9.** PMID 23807318
02: Chen M, Cai Y, Li S, et al. Late-onset carnitine-acylcarnitine translocase deficiency with SLC25A20 c.199-10T>G variation: Case report and pathologic analysis of liver biopsy. Front Pediatr 2020;8:585646. PMID 33194920
03: Chinen Y, Yanagi K, Nakamura S, et al. A novel homozygous missense SLC25A20 mutation in three CACT-deficient patients: clinical and autopsy data. Hum Genome Var 2020;7:11. PMID 32337051
04: Geven WB, Niezen-Koning KE, Timmer A, van Loon AJ, Wanders RJ, van Spronsen FJ. Pre-eclampsia in a woman whose child suffered from lethal carnitine-acylcarnitine translocase deficiency. BJOG 2007;114:1028-30. PMID 17578469
05: Hui J, Tang NL, Li CK, et al. Inherited metabolic diseases in the Southern Chinese population: spectrum of diseases and estimated incidence from recurrent mutations. Pathology 2014;46(5):375-82. PMID 24992243
06: Huizing M, Iacobazzi V, Ijlst L, et al. Cloning of the human carnitine-acylcarnitine carrier from rat liver mitochondria. Biochim Biophys Acta 1997;61(6):1239-45. PMID 9399886
07: Iacobazzi V, Invernizzi F, Baratta S, et al. Molecular and functional analysis of SLC25A20 mutations causing carnitine-acylcarnitine translocase deficiency. Hum Mutat 2004;24:312-20. PMID 15365988
08: Iacobazzi V, Naglieri MA, Stanley CA, Wanders RJ, Palmieri F. The structure and organization of the human carnitine/acylcarnitine translocase (CACT1) gene2. Biochem Biophys Res Commun 1998;252:770-4. PMID 9837782
09: IJIst L, van Roermund CW, Iacobazzi V, et al. Functional analysis of mutant human carnitine acylcarnitine translocases in yeast. Biochem Biophys Res Commun 2001;26;280:700-6. PMID 11162577
10: Indiveri C, Iacobazzi V, Giangregorio N, Palmieri F. The mitochondrial carnitine carrier protein; cDNA cloning, primary structure and comparison with other mitochondrial transport proteins. Biochem J 1997;321:713-9. PMID 9032458
11: Kritzer A, Tarrant S, Sussman-Karten, et al. Use of skimmed breast milk for an infant with a long-chain fatty acid oxidation disorder: a novel therapeutic intervention. JIMD Rep 2020;55(1):44-50. PMID 32905135
12: Mahapatra S, Ananth A, Baugh N, Damian M, Enns GM. Triheptanoin: a rescue therapy for cardiogenic shock in carnitine-acylcarnitine translocase deficiency. JIMD Rep 2018:39:19-23. PMID 28689308
13: Morales Corado JA, Lee CU, Enns GM. Carnitine-acylcarnitine translocase deficiency. In: GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle, 2022.**
14: Norris MK, Scott AI, Sullivan S. Tutorial: triheptanoin and nutrition management for treatment of long-chain fatty acid oxidation disorders. J Parenter Enteral Nutr 2020;45(2):230-8. PMID 33085788
15: Pasquadibisceglie A, Quadrotta V, Polticelli F. In silico analysis of the structural dynamics and substrate recognition determinants of the human mitochondrial carnitine/acylcarnitine SLC25A20 transporter. Int J Mol Sci 2023;24(4):3946. PMID 36835358
16: Ryder B, Inbar-Feigenberg M, Glamuzina E, et al. New insights into carnitine-acylcarnitine translocase deficiency from 23 cases: management challenges and potential therapeutic approaches. J Inherit Metab Dis 2021;44(4):903-15. PMID 33634872
17: Stanley CA. New genetic defects in mitochondrial fatty acid oxidation and carnitine deficiency. Adv Pediatr 1987;34:59-88. PMID 3318304
18: Stanley CA, Hale DE, Berry GT, Deleeuw S, Boxer J, Bonnefont JP. A deficiency of carnitine-acylcarnitine translocase in the inner mitochondrial membrane. N Engl J Med 1992;327:19-23. PMID 1598097
19: Stanley CA, Palmieri F, Bennett MJ. Disorders of the mitochondrial carnitine shuttle. In: Valle DL, Antonarakis S, Ballabio A, Beaudet AL, Mitchell GA, editors. The online metabolic and molecular bases of inherited disease. New York: McGraw-Hill, 2019.**
20: Tein I. Disorders of fatty acid oxidation. Handb Clin Neurol 2013;113:1675-88. PMID 23622388
21: Vatanavicharn N, Yamada K, Aoyama Y, et al. Carnitine-acylcarnitine translocase deficiency: Two neonatal cases with common splicing mutation and in vitro bezafibrate response. Brain Dev 2015;37(7):698-703. PMID 25459972
22: Vitoria I, Martín-Hernández E, Peña-Quintana L, et al. Carnitine-acylcarnitine translocase deficiency: experience with four cases in Spain and review of the literature. JIMD Rep 2015;20:11-20. PMID 25614308
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24: Wang G, Wang J, Douglas G, et al. Expanded molecular features of carnitine acyl-carnitine translocase (CACT) deficiency by comprehensive molecular analysis. Mol Genet Metab 2011;103: 349-57. PMID 21605995
25: Yan HM, Hu H, Ahmed A, et al. Carnitine acylcarnitine translocase deficiency with c.199 10 T>G and novel c.1A>G mutation: two case reports and brief literature review. Medicine (Baltimore) 2017;96(45):e8549. PMID 29137068

Contributors

All contributors' financial relationships have been reviewed and mitigated to ensure that this and every other article is free from commercial bias.

Author

Georgianne Arnold MD

Dr. Arnold of UPMC Children's Hospital of Pittsburgh received research grants from Biomarin and Utragenyx for clinical trial work.
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Editor

Deepa S Rajan MD

Dr. Rajan of UPMC Children's Hospital of Pittsburgh has no relevant financial relationships to disclose.
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Former Authors

Roser Pons MD
Tyler Reimschisel MD
Jennifer Friedman MD
Charles A Stanley MD (original author)

Patient Profile

Age range of presentation: 0-01 month
Sex preponderance: No sex preponderance
Heredity: Autosomal recessive inheritance. Family history should be obtained, but most rare autosomal recessive disorders do not have a known family history until the first affected child is recognized.
Population groups selectively affected: none selectively affected
Occupation groups selectively affected: none selectively affected

ICD & OMIM codes

ICD-9: Other specified disorders of metabolism: 277.8
ICD-10: Metabolic disorders: E70-E90
OMIM: Carnitine-acylcarnitine translocase deficiency: #212138

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Carnitine-acylcarnitine translocase deficiency

Differential Diagnosis

urea cycle defects
arrhythmia
congenital cardiomyopathy
congenital dysrhythmia
congenital malformations
- infections
- metabolic errors
- other inborn errors of mitochondrial fatty acid oxidation
- severe perinatal insults

Also Relevant

Carnitine palmitoyltransferase 1A deficiency
Carnitine palmitoyltransferase II deficiency
Hyperammonemia not caused by liver failure
Medium-chain acyl-coA dehydrogenase deficiency
Multiple acyl-CoA dehydrogenase deficiency

Clinical Categories

Neurogenetic Disorders

Web References

Testing

Mitochondrial Disorders

Carnitine-acylcarnitine translocase deficiency

Carnitine-acylcarnitine translocase deficiency

Introduction

Overview

Key points

Historical note and terminology

Clinical manifestations

Presentation and course

Prognosis and complications

Clinical vignette

Biological basis

Etiology and pathogenesis

Epidemiology

Prevention

Differential diagnosis

Associated or underlying disorders

Diagnostic workup

Management

Special considerations

Pregnancy

References

Contributors

Author

Editor

Former Authors

Patient Profile

ICD & OMIM codes

This is an article preview.
Start a Free Account
to access the full version.

Questions or Comment?

Also in This Category

Carnitine palmitoyltransferase II deficiency

Pyruvate carboxylase deficiency

Pelizaeus-Merzbacher disease

Vanishing white matter disease

Wilson disease

Aromatic L-amino acid decarboxylase deficiency

White matter abnormalities in the brain

Hypermethioninemia

Carnitine-acylcarnitine translocase deficiency

Introduction

Overview

Key points

Historical note and terminology

Clinical manifestations

Presentation and course

Prognosis and complications

Clinical vignette

Biological basis

Etiology and pathogenesis

Epidemiology

Prevention

Differential diagnosis

Associated or underlying disorders

Diagnostic workup

Management

Special considerations

Pregnancy

References

Contributors

Author

Editor

Former Authors

Patient Profile

ICD & OMIM codes

This is an article preview. Start a Free Account to access the full version.

Questions or Comment?

Also in This Category

Carnitine palmitoyltransferase II deficiency

Pyruvate carboxylase deficiency

Pelizaeus-Merzbacher disease

Vanishing white matter disease

Wilson disease

Aromatic L-amino acid decarboxylase deficiency

White matter abnormalities in the brain

Hypermethioninemia

This is an article preview.
Start a Free Account
to access the full version.