ESPE Abstracts

The Loeys-Dietz-Syndrome is a connective tissue disease, which belongs to the group of Marfanoid syndromes. LDS is classified into 6 different subtypes according to the underlying mutation. All mutations are autosomal dominant inherited. Patients with Loeys-Dietz-Syndromes are characterized from cardiovascular and skeletal malformations, like aneurysms of aorta and other arteries, pectus excavatum, pectus carinatum, chicken- or funnel breast, arachnodactyly clubfoot, scoliosis, instable backbone and luxibarian joints, craniopharyngeal deformations like wide-apart eyes, cleft palate, uvula bifida or craniosynostosis. Dermatological changes could include velvety ‘or transparent skin with visible veins. The patients are prompt to develop allergic and autoimmune diseases. Furthermore, they can have. The differential diagnose includes Marfan syndrome and other marfanoid Syndromes. The first case was presented in the JA-PED 2023 in Ulm. A 16-year-old male patient was presented initially with neutropenia, polydipsia, polyuria, up to 5-kilogram weight loss and was diagnosed with Type 1 Diabetes mellitus with a Hba1c of by 12,7% and positive diabetes associated autoantibodies (isles-associated antibodies (ICA Titer 80 (normal value <5), GAD65-Antibodies 20,96 U/ml (Normal value <5), IA2-antibodies >4000 U/ml (<10) and IAA 6,5U/ml (<2,4). Due to scoliosis, arachnodactyly, extraordinary funnel chest, with costal flaring, with a shifted heart axis with a Haller Index of 7,8. The muscles were very pronounced due to the lack of fatty tissue. The bodyweight was 56,55 kg (SDS -1,21), height of 189,0 cm (SDS 1,43) and BMI 15,8 kg/m² (SDS- 2,65). A molecular genetic examination showed a mutation on[WS1] [PK2] TGFBR2 gene (c.1490G>A;p.Arg497Gln (het.) This mutation was never described before on patients with LDS 2. The second case was a 17-year-old male patient who was diagnosed on the age of 4 years with hypothyroidism due to thyroid gland hypoplasia, complaint with the age of 17 with pre-syncopal episodes, dizziness. He had a funnel chest, arachnodactyly, and scoliosis. A molecular genetic examination which showed a mutation in TGFB2 c.494G|Ap.(Arg165Gln) chr1>218578658). An echocardiography showed no pathological signs. The above-mentioned mutation causes an amino acid change which leads to a protein dysfunction. As far as we know, this variation of mutation was never described again in the literature, it was however described in cases of patient with thoracal-aortal diseases. Conclusively, LDS as marfanoid syndrome could be associated with type 1 diabetes mellitus, an autoimmune disease with devastating chronic complications on arteries. Could thyroid hypoplasia be an atypical sign of LDS is a rising question in the second case.