ContentsSynopsisCodesLook ForDiagnostic PearlsDifferential Diagnosis & PitfallsBest TestsManagement PearlsTherapyReferencesView all Images (6)
Xanthoma tendinosum
Other Resources UpToDate PubMed

Xanthoma tendinosum

Print Images (6)
Contributors: Laurie Good MD, Lowell A. Goldsmith MD, MPH
Other Resources UpToDate PubMed


Tendinous xanthomas (xanthoma tendinosum) are fatty deposits on tendons under the skin that almost always indicate an underlying disorder of lipid metabolism. They typically appear as smooth, firm nodules overlying extensor tendons of the elbows, knees, or hands or, classically, the Achilles tendon, and the skin overlying these nodular deposits is normal.

The underlying lipid disorder may be familial dysbetalipoproteinemia (FD), familial hypercholesterolemia (FH), or hepatic cholestasis. Rarely, patients can develop tendinous xanthomas in the absence of the above disorders, such as in the cases of β-sitosterolemia and cerebrotendinous xanthomatosis (CX). The substance of deposition in β-sitosterolemia is plant sterol, and in the case of CX it is an intermediate from the bile acid synthesis pathway called cholestanol, which gets deposited in almost all tissues in patients with CX.

Patients with CX will present with intellectual disability, cataracts, and / or neurologic symptoms and require prompt therapy to prevent irreversible neurologic damage. The genetic defect responsible for CX is an autosomal recessive mutation in the sterol 27-hydroxylase gene.

The most common cause of tendinous xanthoma is FH, and involvement of Achilles tendon is specific for FH. In FH, heterozygous cases occur in 1 of every 500 people worldwide, whereas homozygous cases occur in 1 of every one million people worldwide. Many treatment options exist for heterozygotes, while heroic interventions are necessary for homozygotes.

Pediatric Patient Considerations:
Not seen in children unless the rare form of homozygous FH is present in the patient or the patient has CX. In either case, a child with tendinous xanthomas requires prompt evaluation and medical treatment to prevent irreversible disease sequelae.


E75.5 – Other lipid storage disorders

69880002 – Xanthoma tendinosum

Look For

Subscription Required

Diagnostic Pearls

Subscription Required

Differential Diagnosis & Pitfalls

Xanthomas can be differentiated from other cutaneous processes through history, ultrasound, aspiration cytology, and/or biopsy.

The entities that present most similarly include the following:

Best Tests

Subscription Required

Management Pearls

Subscription Required


Subscription Required


Subscription Required

Last Updated: 10/01/2018
Copyright © 2019 VisualDx®. All rights reserved.
Xanthoma tendinosum
Print 6 Images
View all Images (6)
(with subscription)
Xanthoma tendinosum : Ankle, Elbow, Extensor distribution, Hypercholesterolemia, Knee, Hands, Smooth nodules
Clinical image of Xanthoma tendinosum
Copyright © 2019 VisualDx®. All rights reserved.