{
  "abstract": "A six-month-old first male infant (fourth child) born at term gestation following a low-risk pregnancy to non-consanguineous parents of mixed European/Black African ethnic descent was retrieved to a tertiary paediatric centre aged six months with severe weight loss, malnutrition, and oedema. On admission he had profound electrolyte disturbance (Calcium 0.79mmol/L, phosphate 0.32mmol/L, potassium 2.2mmol/L, sodium 116mmol/L, Mg 0.46mmol/L, zinc 4.3umol/L), hypoalbuminaemia <10g/L and deranged INR 6.9. He had a widespread erythematous rash and lower limb fixed flexion deformity. Admission weight was 4.6kg, <0.4th centile (birth weight 4.16kg, 75th centile).Whole genome sequencing revealed that the patient is compound heterozygous for two pathogenic DGAT1 nonsense variants (table 1).Management included intravenous electrolyte replacement and antibiotics. The coagulopathy corrected with blood products. He was placed nil-by-mouth and given total parenteral nutrition. MRI brain revealed changes consistent with malnutrition. Echocardiogram was normal. OGD and colonoscopy demonstrated normal macroscopic and histological findings.Continuous nasogastric feeds of amino acid formula with 76 % long chain triglyceride concentration were cautiously introduced with subsequent improved stool output and skin integrity and albumin recovery.Low-fat diet was introduced and the formula was changed to a low fat, whole protein, high (85%) medium-chain triglyceride preparation, but a significant eczema flare resulted in immediate switch back to the previous formula.During food introduction the patient had several further reactions. Allergy testing revealed multiple sensitisations with positive specific-IgE to coconut (4.32 kUA/L), wheat (5.83 kUA/L), egg white (6.06 kUA/L), cow’s milk (7.61kUA/L), hazelnut (0.99 kUA/L with positive primary component cor a9 of 1.16) as well as positive skin prick test to soya and beans.Three weeks after full feeding, he had weight loss, diarrhoea and progressive hypoalbuminaemia. Modular feeds (carbohydrate, amino acid and vitamins and minerals) were initiated. Walnut oil for lipid provision was used as a substitute for coconut-oil based MCT due to aforementioned allergies. After three weeks of modular feeds, the albumin, stools and weight improved with stable serum lipids.The DGAT1 gene is located on chromosome 8 with highest expression in the small intestine.1 It encodes a protein that functions as a metabolic enzyme with key roles in cellular diacylglycerol lipid metabolism, triglyceride synthesis, and adipose tissue formation.2 DGAT1 deficiency is a rare autosomal recessive condition characterised by congenital diarrhoea, protein losing enteropathy and failure to thrive.3 Literature describes 25 mutation sites related to DGAT1 with a total of 31 cases reported worldwide, all presenting within the first 4 months of life and 62% in the neonatal period.3To our knowledge, this a novel genetic variant and is the first reported in an individual of Eastern European and Black African descent. Additionally, the presence of significant IgE-mediated food allergies posed unique challenges in developing the requisite nutritional treatment plan and achieving clinical stability. The patient is now thriving at sixteen months of age (50th and 25th centile for weight and height respectively). The complexities of this case highlights the benefits of true multidisciplinary collaboration in managing patients with rare diseases.References Olivier Goulet, et al. Congenital diarrhoeal disorders: advances in this evolving web of inherited enteropathies. Nat Rev Gastroenterol Hepatol. 2015 May;12(5):293–302. Published online 2015 Mar 17. doi: 10.1038/nrgastro.2015.44; PMCID: PMC7599016 , NIHMSID: NIHMS1626209, PMID: 25782092Robert V, Farese Jr, et al. (Identification of a gene encoding an acyl CoA:diacylglycerol acyltransferase, a key enzyme in triacylglycerol synthesis. Proc Natl Acad Sci U S A. 1998 Oct 27;95(22):13018–13023. doi: 10.1073/pnas.95.22.13018; PMCID: PMC23692; PMID: 9789033.)Case report: diagnosis and treatment of DGAT1 deficiency-induced congenital diarrhoea in two cases and literature review. Front. Paediatr. 16 october 2023, Sec. Paedaitric Gastroenterology, Hepatology and Nutrition, volumw 11-2023, https://doi.org/10.3389/fped.2023.1253800) Xu Lingfen et alAbstract OC75 Table 1",
  "authors": [
    {
      "affiliations": [
        "St George’s Hospital"
      ],
      "name": "Rebecca Walker"
    },
    {
      "affiliations": [
        "St George’s Hospital"
      ],
      "name": "Rajat Kapoor"
    },
    {
      "affiliations": [
        "St George’s Hospital"
      ],
      "name": "Dominika Murgasova"
    },
    {
      "affiliations": [
        "St George’s Hospital"
      ],
      "name": "Meriel McEntagart"
    },
    {
      "affiliations": [
        "St George’s Hospital"
      ],
      "name": "Katrina Stone"
    },
    {
      "affiliations": [
        "Royal Devon and Exeter Hospitals"
      ],
      "name": "Hayley Lees"
    },
    {
      "affiliations": [
        "St George’s Hospital"
      ],
      "name": "Nkem Onyeador"
    }
  ],
  "title": "OC75 DGAT1 deficiency in the context of multiple IgE-mediated food allergies – a unique challenge",
  "uid": "c1541d14-a875-5c67-bbfe-29965d28e4ee"
}