Videocapillaroscopy findings in a Colombian population of healthy volunteers with standardization criteria

Introduction

Videocapillaroscopy is a diagnostic procedure that allows an assessment of the microcirculation in the nailfold of patients with Raynaud's phenomenon. There are few reports of videocapillaroscopic findings in healthy subjects, none in Colombia. It is important to know the findings that exist in the Colombian healthy population to have a reference and define abnormalities in people with diseases.

Objective

Our aim was to describe the standardized qualitative, quantitative videocapillaroscopic findings and the sociodemographic characteristics in healthy volunteers from a Colombian population.

Materials and methods

A cross-sectional descriptive study was conducted at the Simon Bolívar and Hospital Universitario Nacional de Colombia in Bogota, Colombia. Healthy adult volunteers over 18 years of age were included in the study. Two images were taken per finger from the second to fifth of each hand. A pilot test was conducted to refine the procedure and establish the agreement between the evaluators of the test, in which a kappa concordance index was estimated for the findings of capillary density, presence of dilated capillaries, megacapillaries, abnormal morphologies and avascular areas. Subsequently, measurements of the venous loop, arterial loop, apical portion, intercapillary distance, capillary density, presence of dilated capillaries, megacapillaries, avascular zones, and description of capillary morphology were performed. Finally, a capillaroscopic diagnosis was issued by Fast-track flowchart.

Results

One hundred one videocapillaroscopy studies were performed. The age range of the participants was 20–62 years (average 31 years). 59 women and 42 men. A total of 1611 photographs at 200× were analyzed. Agreement between the two observers was excellent for capillary density, dilated capillaries, microhemorrhages and abnormal shapes. The average of each the findings was as follows: capillary density of 8.2 capillaries/mm, apical diameter 14.1 μm, arterial loop 10.8 μm, venous loop 13.7 μm, and intercapillary distance 147 μm. Morphology was evaluated in 10,855 capillaries. The predominant morphology was hairpin with 58.8%, followed by crossed 30.2% tortuous 10.4%, and abnormal forms corresponded to 0.48% of the sample. No avascular or megacapillary zones were documented. In 53 individuals, there were some dilated capillaries (182), corresponding to 1.7% of the capillaries analyzed (median of apical diameter: 23.3 μm). Microhemorrhages was found in 16 volunteers, most of them hemosiderin content. The capillaroscopic diagnosis using the Fast-Track algorithm and standardization criteria were category I (a non-scleroderma pattern) in the entire sample, non-specific abnormal findings were observed in 67 (66.3%) of the 101 videocapillaroscopy analyzes.

Conclusions

In healthy people of our cohort, the most frequent finding was nonspecific isolated abnormalities, but do not conform a scleroderma pattern when Fast-Track algorithm and standardization criteria are applied. In addition to ectasias up to 36 μm, microhemorrhages with or without hemosiderin, rare abnormal and decreased capillary densities. Avascular or megacapillary zones were uncommon observed in these healthy subjects.