case_images: PMC9821311_01
case_images: Bilateral achilles tendon xanthomas in case 1 (arrows)
case_images: cureus-0015-00000033378-i01.jpg
case_images: PMC9821311_01_cureus-0015-00000033378-i01.jpg
case_images: FIG1
case_images: History and clinical examination revealed bilateral tendon xanthomas on the Achilles and patellar tendons (Figure 1), an immature cataract in the right eye, pseudophakia in the left eye, a moderate intellectual disability, and cerebellar dysfunction in terms of ataxia and incoordination, which worsened recently.
case_images: MRI of the right ankle in case 1. MRI T1 image in sagittal section showed tendon xanthoma with intermediate signal intensity in the tendo achilles (arrow)
case_images: cureus-0015-00000033378-i02.jpg
case_images: PMC9821311_01_cureus-0015-00000033378-i02.jpg
case_images: FIG2
case_images: MRI of the right ankle in the sagittal T1 section showed tendon enlargement with tendon xanthoma showing intermediate signal intensity (Figure 2), and MRI of the brain in the T2 sagittal and axial sections showed bilateral dentate nucleus calcification and bilateral cerebellar atrophy (Figure 3A-3B).
case_images: MRI brain finding of case 1. MRI brain revealed (A) T2 sagittal section showing cerebellar atrophy (arrow) and (B) T2 axial section showing bilateral symmetrical hypointensities involving dentate nuclei suggesting calcification (arrows)
case_images: cureus-0015-00000033378-i03.jpg
case_images: PMC9821311_01_cureus-0015-00000033378-i03.jpg
case_images: FIG3
case_images: MRI of the right ankle in the sagittal T1 section showed tendon enlargement with tendon xanthoma showing intermediate signal intensity (Figure 2), and MRI of the brain in the T2 sagittal and axial sections showed bilateral dentate nucleus calcification and bilateral cerebellar atrophy (Figure 3A-3B).
case_images: Electropherogram in affected siblings. Electropherogram shows homozygous missense variant c.380G>A(p.Arg127Gln) denoted by arrows
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case_images: PMC9821311_01_cureus-0015-00000033378-i04.jpg
case_images: FIG4
case_images: Based on the above clinical picture, cerebrotendinous xanthomatosis was suspected, and genetic testing identified a homozygous missense variant c.380G>A in exon 2 of the CYP27A1 gene (ENST00000258415.9) that results in the substitution of amino acid at codon position 127 (p.Arg127Gln) (Figure 4).
case_images: PMC9821311_02
case_images: Bilateral achilles tendon xanthoma in case 2 (arrows)
case_images: cureus-0015-00000033378-i05.jpg
case_images: PMC9821311_02_cureus-0015-00000033378-i05.jpg
case_images: FIG5
case_images: A 27-year-old male, who is the younger sibling of the above-mentioned case, presented with bilateral Achilles (Figure 5), patellar tendon xanthomas since childhood, and a clinical neurological examination within normal limits.
case_images: MRI image of the left ankle in case 2. MRI sagittal T1 image revealed tendon xanthoma in tendo achilles of left side (arrow)
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case_images: PMC9821311_02_cureus-0015-00000033378-i06.jpg
case_images: FIG6
case_images: T1 sagittal MRI of the left ankle revealed tendon enlargement with tendon xanthoma showing intermediate signal intensity in the tendo Achilles (Figure 6), and FLAIR axial MRI of a younger sibling revealed normal bilateral dentate nucleus with no cerebellar atrophy (Figure 7).
case_images: MRI brain findings in case 2. MRI brain FLAIR axial section showed normal bilateral dentate nucleus with no cerebellar atrophy (arrow)
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case_images: PMC9821311_02_cureus-0015-00000033378-i07.jpg
case_images: FIG7
case_images: T1 sagittal MRI of the left ankle revealed tendon enlargement with tendon xanthoma showing intermediate signal intensity in the tendo Achilles (Figure 6), and FLAIR axial MRI of a younger sibling revealed normal bilateral dentate nucleus with no cerebellar atrophy (Figure 7).