Purpose: Our study was aimed to evaluate the usefulness of tendon ultrasound to clarify the
meaning of tendon xanthomas (TX) in familial hypercholesterolemia (FH). TX are nodules
or diffuse enlargements of tendons, particularly Achilles tendons, almost pathognomonic
of FH. TX are however clinically detectable only in 30% of patients. In FH the presence
of tendon complications would seem to parallel vascular involvement, and clinical
detection of TX apparently identifies a group of particularly high risk subjects.
Ultrasound is able to evaluate in very accurate way the vascular districts and Achilles
tendons, offers an opportunity to better understand the diagnostic, prognostic and
pathological meaning of TX in FH.
Material and methods: 43 patients (among which 22 FH) underwent Achilles tendon ultrasound and carotid
and femoral artery vascular ultrasound.
Results: The Achilles tendons of FH subjects where thicker than the other groups (5.6 vs.
8.4 mm). There was a high prevalence of ultrasound-detected TX in FH whose physical
exam was normal (62.5%). We identified a sensible (72.7%) and specific (85.7%) ultrasound
diagnostic criterion for FH. FH subjects had higher intima-media-thickness (IMT) and
higher prevalence of atherosclerotic plaques both in carotid and femoral arteries.
Only in FH there was a correlation between carotid IMT and Achilles tendon thickness.
FH subjects with premature atherosclerosis had a higher prevalence of clinically detectable
TX (40.0 vs. 23.5%) and a higher tendon thickness (11.2 vs. 7.4 mm) but a similar
prevalence of ultrasound detectable TX.
Conclusion: Ultrasound of Achilles tendon facilitates substantially the diagnosis of FH. Ultrasound
reveals that minor tendon alterations affect the majority of FH patients. Data suggest
that the tendon thickness rather than mere presence of TX is related to cardiovascular
risk, this is supported also by the finding of a correlation between ATT and IMT which
was unique to FH subjects.
