Bilateral Achilles Tendon Xanthomas in a 17-Year-Old Female: A Clinicoradiological Case Report.

Introduction: Achilles tendon xanthomas are uncommon lipid-rich lesions associated with familial hypercholesterolemia, typically affecting adult patients. Presentation during childhood or adolescence is uncommon, particularly among female patients, and often indicates severe underlying dyslipidemia. Early recognition is important to prevent long-term complications. Case presentation: A 17-year-old Indian girl presented with bilateral posterior ankle swelling and discomfort. Clinical examination revealed firm, non-tender, fusiform swellings adherent to both Achilles tendons. Laboratory evaluation revealed elevated low-density lipoprotein cholesterol and apolipoprotein B levels, consistent with heterozygous familial hypercholesterolemia. Magnetic resonance imaging (MRI) of both ankles demonstrated diffuse tendon thickening with a hypointense signal on T2-weighted sequences and speckled heterogeneity on proton density fat-suppressed images, confirming xanthomatosis. Surgical excision was performed on the right side, and histopathological examination confirmed the presence of foam cells and cholesterol clefts. The left-sided swelling was managed conservatively, with serial follow-up demonstrating stable morphology and no progression. Discussion: Radiological assessment using MRI allowed a clear distinction between xanthomas and other tendinopathies. Given the patient's functional limitations, surgery provided mechanical relief, whereas lipid-lowering therapy addressed the underlying systemic risk. Conclusion: Recognition of tendon xanthomas in adolescents supports timely identification of hereditary dyslipidemia and initiation of coordinated orthopedic and metabolic care, with potential long-term cardiovascular benefit.