{
  "abstract": "Carnitine is an amino acid derivative synthesized endogenously from methionine and lysine. It is also obtained from dietary sources like meat and dairy products and absorbed in the small intestine. 1 Its principal function is to transport long-chain fatty acids across the mitochondrial membrane, facilitating their β-oxidation to produce energy. This energy is critical for organs with high metabolic demands such as the heart and skeletal muscles, especially during exercise or fasting.Patients with metabolic disorders, renal or liver insufficiency, intestinal failure patients dependent on long-term parenteral nutrition (PN), neonates, and children on antiepileptic medications are at risk of deficiency.2 Clinical manifestations are hypoglycaemia, fatigue, muscle weakness, and cardiomyopathy.3 Importantly, standard PN formulations typically lack carnitine unless it is specifically supplemented.This study aimed to evaluate the prevalence of carnitine deficiency in paediatric patients receiving long-term PN and to assess the association between carnitine status and enteral feeding tolerance.We conducted a retrospective review of 36 children receiving PN for six months between 2021 and 2025. Patient data included demographics, PN duration, enteral feeding status, underlying diagnoses, carnitine serum levels, and supplementation. Carnitine deficiency was categorized as mild (15–24 μmol/L), moderate (5–14 μmol/L), or severe (<5 μmol/L).4The cohort had a median age of 10.2 years (range 1.11–17.11 years) and a median PN duration of 7 years (range 6 months to 18 years). Underlying conditions included intestinal motility disorders (47%), short bowel syndrome (SBS, 39%), tufting enteropathy (6%), lipid metabolism disorder, tyrosinemia, and dystonic cerebral palsy (3% each).Carnitine deficiency was identified in 27 patients (75%). Among these, 48% had intestinal motility disorders, 37% had SBS. Additionally, 2 patients (6%) were diagnosed with tufting enteropathy, 1 (3%) with a lipid metabolism disorder, 1 (3%) with tyrosinemia, and 1 (3%) with dystonic cerebral palsy. Nine patients (25%) had normal carnitine levels despite long-term PN exposure (mean duration ~6 years). Of these, five had SBS, and four had motility disorders. The mean duration of PN was similar in carnitine-deficient patients (6.0 ± 4.2 years) and those with normal levels (6.0 ± 5.6 years), with no significant difference (p = 0.99). Only three patients had received carnitine supplementation.Regarding feeding modality, 22 patients were on combined PN and enteral nutrition, while 14 patients received exclusive PN. Carnitine deficiency was significantly more prevalent in the exclusive PN group, with all 14 patients (100%) deficient compared to 13 out of 22 (59%) in the combined feeding group (p = 0.002).Carnitine deficiency is common among children on long-term PN, particularly in those unable to tolerate enteral feeds. The absence of dietary intake likely exacerbates carnitine depletion, as endogenous synthesis alone may be insufficient to meet metabolic demands. Routine monitoring of serum carnitine levels every three months, along with the incorporation of carnitine supplementation in parenteral nutrition formulations for patients receiving long-term PN with limited or no enteral intake, is recommended. Further prospective studies are needed to establish guidelines for supplementation and to evaluate its impact on clinical outcomes.References Crill CM, Helms RA. The use of carnitine in paediatric nutrition. Nut Clin Pract. 2007 Apr;22(2):204–13.Winther B, Jackson D, Mulroy C, MacKay M. Evaluation of serum carnitine levels for paediatric patients receiving carnitine-free and carnitine-supplemented parenteral nutrition. Hosp Phar. 2014 Jun;49(6):549–53.Dhanusha K, Elavarasi E, Vasanth Kumar M, Srinivasan R. Understanding causes, symptoms, and treatment options of carnitine deficiency. J Pharma Insights Res. 2024 Apr 9;2(2):104–9.Longo N, Amat di San Filippo C, Pasquali M. Primary carnitine deficiency. In: Adam MP, Feldman J, Mirzaa GM, et al., editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993–2022. Available from: https://www.ncbi.nlm.nih.gov/books/NBK84551/",
  "authors": [
    {
      "affiliations": [
        "Great Ormond Street Hospital for Children NHS Foundation Trust London"
      ],
      "name": "Ayesha Merchant"
    },
    {
      "affiliations": [
        "Great Ormond Street Hospital for Children NHS Foundation Trust London"
      ],
      "name": "Hannah Littlechild"
    },
    {
      "affiliations": [
        "Great Ormond Street Hospital for Children NHS Foundation Trust London"
      ],
      "name": "Sophie Montgomery Stuart"
    },
    {
      "affiliations": [
        "Great Ormond Street Hospital for Children NHS Foundation Trust London"
      ],
      "name": "Morgan Walker"
    },
    {
      "affiliations": [
        "Great Ormond Street Hospital for Children NHS Foundation Trust London"
      ],
      "name": "Rulla Al-Araji"
    },
    {
      "affiliations": [
        "Great Ormond Street Hospital for Children NHS Foundation Trust London"
      ],
      "name": "Susan Hill"
    },
    {
      "affiliations": [
        "Great Ormond Street Hospital for Children NHS Foundation Trust London"
      ],
      "name": "Jutta Koeglmeier"
    }
  ],
  "title": "OC9 Carnitine status in children on long term parenteral nutrition - a retrospective study at a tertiary centre",
  "uid": "ea67600b-b425-593f-b7a6-b001c27fa547"
}