Assessment of capillary density in systemic sclerosis with three different capillaroscopic methods

Area of Science:

• Dermatology
• Rheumatology
• Microscopy

Background:

• Systemic sclerosis (SSc) frequently presents with early capillary abnormalities, including loop enlargement or loss.
• Nailfold capillaroscopy is crucial for diagnosing SSc and monitoring disease progression.

Purpose of the Study:

• To compare the efficacy of three distinct capillaroscopic methods for quantifying capillary density in SSc patients.
• To evaluate the agreement between direct counting and computer-assisted image analysis for capillary density measurement.

Main Methods:

• Employed stereo-zoom microscopy (20x) for direct counting and image analysis.
• Utilized computerized nailfold video capillaroscopy (300x) with coded images.
• Assessed capillary density (loops/mm) in 40 SSc patients and 21 controls.

Main Results:

• All three methods revealed significantly lower capillary density in SSc patients (limited cutaneous SSc and diffuse cutaneous SSc) compared to controls.
• Good agreement was observed between the methods in control subjects.
• Direct counting yielded lower capillary density values than computer-based methods in SSc patients.

Conclusions:

• The three capillaroscopic methods demonstrated good inter-method agreement for assessing capillary density.
• All evaluated methods successfully differentiated between SSc patients and healthy individuals.
• Capillary density measurement via capillaroscopy is a reliable diagnostic tool for systemic sclerosis.