Nailfold capillaroscopy in common non-rheumatic conditions: A systematic review and applications for clinical practice

Nailfold Capillaroscopy: A Comprehensive Review on Its Usefulness in Both Clinical Diagnosis and Improving Unhealthy Dietary Lifestyles

Since the 1970s, the utility of nailfold capillaroscopy (NFC) in diagnosing rheumatological disorders such as systemic sclerosis has been well established. Further studies have also shown that NFC can detect non-rheumatic diseases such as diabetes, glaucoma, dermatitis, and Alzheimer disease. In the past decade, nailfold capillary morphological changes have also been reported as symptoms of unhealthy lifestyle habits such as poor diet, smoking, sleep deprivation, and even psychological stress, all of which contribute to slow blood flow. Therefore, studying the relationships between the morphology of nailfold capillaries and lifestyle habits has a high potential to indicate unhealthy states or even pre-disease conditions. Simple, inexpensive, and non-invasive methods such as NFC are important and useful for routine medical examinations. The present study began with a systematic literature search of the PubMed database followed by a summary of studies reporting the assessment of morphological changes detected by NFC, and a comprehensive review of NFC's utility in clinical diagnosis and improving unhealthy dietary lifestyles. It culminates in a summary of dietary and lifestyle health promotion strategy, assessed based on NFC and other related measurements that indicate healthy microvascular blood flow and endothelial function.

Computerized nailfold video-capillaroscopy in type 2 diabetes: A cross-sectional study on 102 outpatients

BACKGROUND

Type 2 diabetes (T2D) is a chronic disease that negatively affects vascular health. A careful assessment of chronic complications, including microcirculation, is mandatory. The computerized nailfold video-capillaroscopy (CNVC) accurately examines the nailfold microvasculature, but its suitability in T2D is currently under investigation.

AIMS

To describe nailfold microvasculature in T2D patients regarding the level of glucose control and chronic microvascular and macrovascular complications.

METHODS

This is a cross-sectional study on 102 consecutive and unselected outpatients with T2D who had undergone CNVC examination. The examination was carried out by using an electronic video-capillaroscope with 300x magnification. Capillaroscopic appearance and capillary changes were described according to well-established parameters. Capillaroscopic parameters were compared between patients with poor glucose control (HbA1c ≥7%) and those with better glucose control (HbA1c <7%) and between patients with chronic complications and those without. Chronic complications were deduced from the anamnestic, laboratory, and instrumental data and the five-item International Index of Erectile Function (IIEF-5) questionnaire.

RESULTS

Nailfold capillaries in patients with HbA1c ≥7% were thicker (p = .019) and longer (p = .021) than in those with better glucose control. Ectasias (p = .017) and microaneurysms (p = .045) were more frequently observed in patients with HbA1c ≥7.0% than those with HbA1c <7.0%. Patients with ED, compared to those without, had a lower frequency of bizarre-shaped capillaries (p = .02). Microaneurysms (p = .02) were more frequently described in patients with carotid stenosis (>20%) than those without.

CONCLUSION

Relevant nailfold microvascular alterations were observed in T2D, most of which were associated with poor glycemic control, ED, and carotid stenosis. Further investigation is needed to recognize the role of CNVC in predicting the onset and evolution of chronic complications and monitoring the effectiveness of antihyperglycemic treatments on microcirculation.

Nailfold Videocapillaroscopic Alterations as Markers of Microangiopathy in COVID-19 Patients

Nailfold videocapillaroscopic alterations have been described in COVID-19, but their correlations with biomarkers of inflammation, coagulation and endothelial perturbation are still unclear, and no information is available on nailfold histopathology. Nailfold videocapillaroscopy was performed on fifteen patients with COVID-19 in Milan, Italy and the signs of microangiopathy were correlated with plasma biomarkers of inflammation (C reactive protein [CRP], ferritin), coagulation (D-dimer, fibrinogen), endothelial perturbation (Von Willebrand factor [VWF]) and angiogenesis (vascular endothelial growth factor [VEGF]) along with genetic drivers of COVID-19 susceptibility. Histopathological analysis of autoptic nailfold excisions was performed on fifteen patients who died for COVID-19 in New Orleans, United States. All COVID-19 patients studied with videocapillaroscopy showed alterations rarely seen in healthy individuals consistent with microangiopathy, such as hemosiderin deposits (sign of microthrombosis and microhemorrhages) and enlarged loops (sign of endotheliopathy). The number of hemosiderin deposits correlated both with ferritin and CRP levels (r = 0.67, p = 0.008 for both) and the number of enlarged loops significantly correlated with the levels of VWF (r = 0.67, p = 0.006). Ferritin levels were higher in non-O groups, determined by the rs657152 C > A cluster, (median 619, min-max 551-3266 mg/dL) than in the O group (373, 44-581 mg/dL, p = 0.006). Nailfold histology revealed microvascular damage, i.e., mild perivascular lymphocyte and macrophage infiltration and microvascular ectasia in the dermal vessels of all cases, and microthrombi within vessels in five cases. Alterations in nailfold videocapillaroscopy and elevated biomarkers of endothelial perturbation that match histopathologic findings open new perspectives in the possibility of non-invasively demonstrating microangiopathy in COVID-19.

Nailfold Videocapillaroscopy for Non-Invasive Assessment of Microcirculation and Prognostic Correlation with Endothelial Dysfunction, Cardiovascular Risk Factors, and Non-HLA Antibodies in Heart Transplant Recipients: A Pilot Study

Early identification of allograft vasculopathy and the concomitant elimination of adverse risk factors is essential for improving the long-term prognosis of heart transplant (HTx) recipients with underlying cardiovascular disease (CVD). The major aim of this pilot study was to conduct a non-invasive imaging evaluation of the HTx patient microcirculation by employing nailfold video-capillaroscopy (NVC) in a well-characterized patient and control cohort, and to correlate these data with endothelial cell function, accompanied by studies of traditional cardiovascular risk factors and non-HLA antibodies in HTx recipients. Ten patients undergoing HTx (mean age of 38 ± 14 years) were recruited for the study and compared to a control group of 12 well-matched healthy volunteers (mean age 35 ± 5 years) with normal body mass index (BMI). Detailed medical records were collected from all individuals. NVC was performed using CapillaryScope 200 MEDL4N microscope. For functional readout and correlation analysis, endothelial cell network formation in conjunction with measurements of patient serum levels of vascular endothelial growth factor (VEGF) and non-HLA autoantibodies directed against the angiotensin II type-1-receptor (anti-AT1R-Ab), endothelin-1 type-A-receptor (anti-ETAR-Ab), protease-activated receptor-1 (anti-PAR-1-Ab), and VEGF-A (anti-VEGF-A-Ab) were studied. Our NVC analysis found that the average apical loop diameter of nailfold capillaries was significantly increased in HTx recipients (p = 0.001). In addition, HTx patients with more prominent changes in capillaroscopic patterns were characterized by the presence of traditional cardiovascular risk factors, and HTx patients had increased levels of anti-AT1R-ab, anti-ETAR-ab, and anti-VEGF-A-Ab (p = 0.017, p = 0.025, and p = 0.003, respectively). Capillary diameters most strongly correlated with elevated serum levels of troponin T and triglycerides (R = 0.69, p = 0.028 and R = 0.81, p = 0.004, respectively). In conclusion, we found that an abnormal NVC pattern in HTx patients is associated with traditional CVD risk factors and that NVC is a useful non-invasive tool to conveniently monitor changes in the microvasculature of HTx patients.

Nailfold capillaroscopy and deep learning in diabetes

OBJECTIVE

To determine whether nailfold capillary images, acquired using video capillaroscopy, can provide diagnostic information about diabetes and its complications.

RESEARCH DESIGN AND METHODS

Nailfold video capillaroscopy was performed in 120 adult patients with and without type 1 or type 2 diabetes, and with and without cardiovascular disease. Nailfold images were analyzed using convolutional neural networks, a deep learning technique. Cross-validation was used to develop and test the ability of models to predict five5 prespecified states (diabetes, high glycosylated hemoglobin, cardiovascular event, retinopathy, albuminuria, and hypertension). The performance of each model for a particular state was assessed by estimating areas under the receiver operating characteristics curves (AUROC) and precision recall curves (AUPR).

RESULTS

A total of 5236 nailfold images were acquired from 120 participants (mean 44 images per participant) and were all available for analysis. Models were able to accurately identify the presence of diabetes, with AUROC 0.84 (95% confidence interval [CI] 0.76, 0.91) and AUPR 0.84 (95% CI 0.78, 0.93), respectively. Models were also able to predict a history of cardiovascular events in patients with diabetes, with AUROC 0.65 (95% CI 0.51, 0.78) and AUPR 0.72 (95% CI 0.62, 0.88) respectively.

CONCLUSIONS

This proof-of-concept study demonstrates the potential of machine learning for identifying people with microvascular capillary changes from diabetes based on nailfold images, and for possibly identifying those most likely to have diabetes-related complications.

Does the use of nail cosmetics interfere with the reporting of nailfold capillaroscopy?

Capillaroscopy is a non-invasive tool evaluating the nail-fold capillaries, especially in approach to Raynaud's phenomenon (RP) and scleroderma (SSc) spectrum of diseases. It was recommended that the patients should not use any cosmetic procedure involving the nailfold to avoid misinterpretations. Therefore, we aimed to find the problems of using or recent removal of the nail polishes/artificial nails/henna before doing capillaroscopy. During 10 years, we looked for all capillaroscopy reports and nail fold images of patients who referred for capillaroscopy and had used or recently removed nail polish/artificial nail/henna in order to find the presence of any artifacts or misinterpretations in reports. Sixty-three patients were identified that had used or removed the nail cosmetic during 10 days before capillaroscopy. In patients who used nail polish, removed their nail polish, used artificial nails, or removed the artificial nails, and those using henna, 16.2%, 36.4%, 3.8%, 0%, and 1.4% of nail folds showed some stains in the upper part of the nail fold area, respectively, that had no interference with the report due to their distinct color. However, few areas were covered with polish stains in patients who removed the polish recently. The presence of nail cosmetics including nail polishes, henna, and artificial nails at the time of capillaroscopy does not induce a significant misinterpretation in capillaroscopy. However, some colored stains which were mostly distinguishable from hemorrhages could be seen. The removal of them 10 days before the time of capillaroscopy did not decrease the cosmetic artifacts. Key Points • The presence of nail cosmetics including nail polishes, henna, and artificial nails at the time of capillaroscopy does not induce a significant misinterpretation in capillaroscopy. • The removal of nail polish 10 days before the time of capillaroscopy did not decrease the procedure artifacts. • The removal of nail polish 10 days before capillaroscopy increased the area of artifacts and coverage of the study background.

Structural and functional state of various parts of skin microcirculation at an early stage of hypertension in working-age men

STUDY PURPOSE

To conduct a cross-sectional study on the structural and functional characteristics of various parts of skin microcirculation in working-age men with newly diagnosed hypertension (HTN).

MATERIALS AND METHODS

The study included 118 male participants (ages 30 to 60) who were not regularly taking any medicine, had no medical complaints, and subjectively considered themselves healthy at the time of study. All participants underwent a cross-sectional comprehensive medical examination. The following tests were performed: complete blood count, biochemical blood tests, video capillaroscopy (VCS), laser Doppler flowmetry (LDF) and photoplethysmography (PPG) on the left hand fingers, determination of flow-mediated vasodilation of the brachial artery, echocardiography, ultrasound of extracranial and femoral arteries, 24-h ambulatory blood pressure monitoring (ABPM). According to ABPM data, the participants were divided into two equal groups called a control group(CG) and a hypertension group(HG). There were 59 participants with normal BP in CG, and 59 participants with newly diagnosed HTN in HG.

RESULTS

Nailfold VCS of the ring finger revealed no significant differences between the groups at the level of exchange microvessels. According to LDF data, there was no decrease in tissue perfusion and signs of an increase in the activity of endothelial, neurogenic, and myogenic regulation of the tone of precapillary arterioles in the HTN group. According to PPG of the index finger, in contrast to CG, HTN participants had significantly higher values of the following parameters: normalized augmentation index (Alp75) - 3.8 % and - 5.25 % (p < 0.005), stiffness index (SI) - 7.6 m/s and 7.35 m/s (p < 0.05), reflection index (RI) - 36.5 % and 28.4 % (p < 0.005), respectively.

DISCUSSION

Working-age men in the early stage of HTN have neither capillary rarefaction nor an increase in the tone of skin precapillary arterioles. The largest contribution to peripheral vascular resistance in the onset of HTN is most likely made by large muscular arterioles, in which the neurogenic regulation of vascular tone predominates.

Evaluation of serum vascular endothelial growth factor level and findings of nailfold capillaroscopy by dermatoscope in the differential diagnosis of palmoplantar psoriasis and palmoplantar eczema

OBJECT

This study aimed to evaluate VEGF level, capillaroscopic findings, and these features for differential diagnosis of palmoplantar psoriasis and eczema patients.

METHODS

This comparative cross-sectional study included 40 patients clinical and histopathologically diagnosed with eczema or psoriasis (20 psoriasis and 20 eczema) and 30 patients of similar age and gender without inflammatory disease in the control group. Serum samples of patients were collected and analyzed for VEGF by enzyme-linked immunosorbent assay (ELISA) and at the same time, we applied capillaroscopy with computerized dermatoscopy qualitatively and semiquantitatively.

RESULTS

In the qualitative evaluation, a decrease in capillary density and a significant increase of the avascular area was in palmoplantar plaque psoriasis (PPP) and palmoplantar eczema (PPE) patients compared to the control group. In the semiquantitative evaluation, the mean score decreased capillary density was significantly higher in PPE than in the PPP and control groups (p < 0.001). Minor morphological change (tortuous, crossed and enlarged capillary) scores were significantly higher in patients with PPE compared to PPP and control groups (p = 0.011). Major morphological change (mega, meandering, branching, bushy, bizarre, and disorganized polymorphic capillary) score was significantly higher in patients with PPP than PPE and the control group (p < 0.001). Major morphological change and m-PPPASI scores were correlated in PPP patients (p < 0.05). Disorganized capillaries in PPP patients were significantly higher than in the PPE and control groups (p < 0.001). There was no significant correlation between serum VEGF value and clinical severity and capillaroscopy findings of the patients.

CONCLUSION

Significant morphological changes were detected between PPP, PPE, and control groups in the qualitative and semi-quantitative evaluation of capillaroscopic findings. In the differential diagnosis of PPP and PPE, major morphological change, especially the presence of disorganized polymorphic capillaries, was considered an important finding in the capillaroscopic evaluation. These capillaroscopic findings may be helpful to discriminate eczema and psoriasis. However, there was no significant relationship between serum VEGF level and the patients' capillaroscopic findings and clinical severity.

Diagnosis of Skin Vascular Complications Revealed by Time-Frequency Analysis and Laser Doppler Spectrum Decomposition

Nowadays, photonics-based techniques are used extensively in various applications, including functional clinical diagnosis, progress monitoring in treatment, and provision of metrological control. In fact, in the frame of practical implementation of optical methods, such as laser Doppler flowmetry (LDF), the qualitative interpretation and quantitative assessment of the detected signal remains vital and urgently required. In the conventional LDF approach, the key measured parameters, index of microcirculation and perfusion rate, are proportional to an averaged concentration of red blood cells (RBC) and their average velocity within a diagnostic volume. These quantities compose mixed signals from different vascular beds with a range of blood flow velocities and are typically expressed in relative units. In the current paper we introduce a new signal processing approach for the decomposition of LDF power spectra in terms of ranging blood flow distribution by frequency series. The developed approach was validated in standard occlusion tests conducted on healthy volunteers, and applied to investigate the influence of local pressure rendered by a probe on the surface of the skin. Finally, in limited clinical trials, we demonstrate that the approach can significantly improve the diagnostic accuracy of detection of microvascular changes in the skin of the feet in patients with Diabetes Mellitus type 2, as well as age-specific changes. The results obtained show that the developed approach of LDF signal decomposition provides essential new information about blood flow and blood microcirculation and has great potential in the diagnosis of vascular complications associated with various diseases.

A pilot study of nailfold capillaroscopy in hereditary transthyretin amyloidosis

Nailfold capillaroscopy (NFC) is a safe and non-invasive imaging tool for evaluating microvascular abnormalities. This retrospective cross-sectional study aimed to analyze the NFC outcomes and clinical characteristics in patients and an asymptomatic carrier with transthyretin (TTR) gene mutation. The participants consist of eight patients with genetically and clinically confirmed hereditary amyloidogenic transthyretin (ATTRv) amyloidosis and one asymptomatic carrier. The TTR gene mutant forms of six male and three female participants from six families were Asp38Ala (five patients), Lys35Asn (three patients), and Ala36Pro (one patient). All participants showed decreased capillary density, dilatated capillaries, and destructed architecture in NFC. Early progression identification of a carrier to patients with symptoms is a major concern from a therapeutic viewpoint in ATTRv amyloidosis. Therefore, further studies with a larger number of subjects will be needed to determine the use of NFC as an early detection tool.

Nailfold Microhemorrhage Segmentation with Modified U-Shape Convolutional Neural Network

Nailfold capillaroscopy is a reliable way to detect and analyze microvascular abnormalities. It is safe, simple, noninvasive, and inexpensive. Among all the capillaroscopic abnormalities, nailfold microhemorrhages are closely associated with early vascular damages and might be present in numerous diseases such as glaucoma, diabetes mellitus, and systemic sclerosis. Segmentation of nailfold microhemorrhages provides valuable pathological information that may lead to further investigations. A novel deep learning architecture named DAFM-Net is proposed for the accurate segmentation in this study. The network mainly consists of U-shape backbone, dual attention fusion module, and group normalization layer. The U-shape backbone generates rich hierarchical representations while the dual attention fusion module utilizes the captured features for fine adjustment. Group normalization is introduced as an effective normalization method to effectively improve the convergence ability of our deep neural network. The effectiveness of the proposed model is validated through ablation studies and segmentation experiments; the proposed method DAFM-Net achieves competitive performance for nailfold microhemorrhage segmentation with an IOU score of 78.03% and Dice score of 87.34% compared to the ground truth.

Sex features of cutaneous microvasculature in healthy working-age people

Aim. To study sex characteristics of cutaneous microvascular structure and function in a cohort of healthy working-age people without cardiovascular diseases.

Material and methods. The study included 35 healthy men (42±4 years) and 34 women (41 ±5 years). The cardiovascular system was assessed in all patients. The microcirculatory bed of the skin was investigated by the following non-invasive methods: 1) computerized video capillaroscopy; 2) laser Doppler flowmetry; 3) photoplethysmography.

Results. According to computerized video capillaroscopy in men, compared with women, there was a smaller number of both functioning capillaries (78 vs 86 capillaries/mm2, respectively (p<0,05)) and their total number (100 vs 120 capillaries/mm2, respectively (p<0,001)). Against the background of a decrease in capillary density in men, there was a higher skin interstitial hydration — 113 vs 96 gm (p<0,005) in men than in women. At the level of precapillary arterioles, where humoral tone regulation prevails. Laser Doppler flowmetry revealed lower pulse amplitude in men than in women — 0,87 vs 1,02 pf, respectively (p<0,05), which indicates a lower arterial blood inflow to exchange microvessels. Against this background, the constrictor response of precapillary arterioles to a sympathetic nervous system stimulation in men is higher than in women — 45% vs 40%, respectively (p<0,05). At the level of large arterioles, where neural tone regulation prevails, photoplethysmography revealed lower augmentation index standardized at a heart rate in men (-4,6 vs 1,7%, respectively, p<0,05), which indicates lower rigidity of muscular vessels in men.

Conclusion. In working-age healthy people, sex differences are noted at all cutaneous microvascular levels, which must be taken into account when planning studies.

Nail Folds Capillaries Abnormalities Associated With Type 2 Diabetes Mellitus Progression and Correlation With Diabetic Retinopathy

Background:

Diabetic retinopathy (DR) is an important microvascular consequence of long-term type 2 diabetes mellitus (T2DM), and it can lead to blindness if not properly diagnosed and managed. Nailfold video capillaroscopy (NVC) is a non-invasive technique for observing capillary microvasculature.

Aim:

We aimed to evaluate the nail folds capillaroscopic alterations in patients with T2DM by NVC and correlated the results to DR, and their relation to disease duration and hemoglobin A1c (HbA1c).

Methods:

This cross-sectional study enrolled 62 cases with T2DM (as per the American Diabetes Association criteria). All patients were subjected to NVC and ophthalmological assessment.

Results:

NVC revealed that Patients with DR showed significantly higher frequencies of tortuous capillaries, branched capillaries and precapillary edema versus non-DR patients with P < .05. The DR patients with longer disease duration (15-20) years had significantly higher frequencies of branched capillaries, tortuous capillaries, microhemorrhages, and dilated apical capillaries. The frequency of tortuosity and precapillary edema were significantly higher in patients with poor glycemic control. The increased capillary width and branched capillaries were detected as predictors of DR in multivariate analysis.

Conclusion:

NVC is a cost-effective, quick, safe, simple, non-invasive, and newly emerging tool to assess the capillaroscopic alterations in diabetic patients as an indicator of severity of DR.

[Assessment of the structural and functional state of blood vessels in patients with hypertrophic cardiomyopathy]

Aim      To evaluate the structural and functional condition of the vasculature using fingertip photoplethysmography and computerized videocapillaroscopy in patients with hypertrophic cardiomyopathy (HCMP).Material and methods  The study included patients with HCMP (n=48; 28 (57 %) men; age, 54.3±13.6 years) and healthy volunteers (control group, n=33, 15 (45 %) men; age, 58.2±8.8 years). Standard laboratory and instrumental examination (blood count and biochemistry, electrocardiography, echocardiography, Holter electrocardiogram monitoring) were performed for all HCMP patients. The condition of vascular wall at various levels of the vasculature was evaluated by fingertip photoplethysmography (apparatus Angioscan-01) and computerized nail-fold videocapillaroscopy (apparatus Capillaroscan-01). The photoplethysmography study analyzed structural parameters, including the arterial wall stiffness index (aSI) of large blood vessels and the resistance index (RI) of small muscular arteries. Endothelial dysfunction was evaluated by the occlusion index (OI) and phase shift (PS). The capillaroscopy study assessed structural parameters, including the resting capillary density (rCD) and the capillary density following venous occlusion (voCD), and functional parameters, including the percentage of perfused capillaries (PPC), the percentage of restored capillaries (PRC), and the capillary density after the reactive hyperemia test (rhCD).Results The study showed increases in aSI (8.8 [6.8; 12.2] and RI (32.5 [17.4; 47.9] in the HCMP group. The OI was significantly lower in the HCMP group (1.3 [1.1; 1.5]) than in the control group (1.8 [1.5; 2.7], р&lt;0.001). Also, PS values were significantly decreased in the HCMP group (4.4 [2.3; 8.6]) compared to the control group (8.4 [5.1; 12.1]. p=0.018). Disorders of structural and functional capillary indexes were observed in HCMP patients compared to the control group; rCD and voCD were decreased in the HCMP group (60 [52.6; 68] and 88 [75; 90], respectively) compared to the control group (75.8 [60; 87] and 90 [73; 101]), however, no intergroup difference reached a statistical significance. The rhCD, PPC, and PRC values were decreased in the HCMP group (66.3 [55; 72], 86.7 [70.9; 104.2] and 1.7 [-6.95; 20.3], respectively) compared to the control group (86 [68.6; 100], 103 [96; 114] and 18.4 [8.1; 27.4], respectively); PPC and PRC values were significantly different (р&lt;0.005 and p&lt;0.004, respectively).Conclusion      In patients with HCMP, fingertip photoplethysmography and computerized videocapillaroscopy showed increased wall stiffness in both large blood vessels and microvasculature, pronounced endothelial dysfunction, and decreases in capillary density and percentage of restored capillaries following respective tests.

The Effect of Ketogenic Diet on Inflammatory Arthritis and Cardiovascular Health in Rheumatic Conditions: A Mini Review

The principle of ketogenic diet (KD) is restriction of carbohydrates to a maximum of 5-10% of the total daily caloric intake, aiming at shifting body metabolism toward ketone bodies. Different studies suggested promising results of KD to help patients to lose weight, to reduce insulin requirements in diabetes, to supplement cancer protocols, to treat neurological conditions and to optimize control of metabolic and cardiovascular diseases. However, literature about the anti-inflammatory properties of KD in rheumatic diseases is still limited. The beneficial effects of weight loss in patients with inflammatory arthritis can be explained by biomechanical and biochemical factors. Obesity is associated with macrophage activation and production of pro-inflammatory cytokines including TNF-α, IL-1b, and IL-6. The clinical effect of KD may be primarily attributed to improvement of insulin sensitivity. Insulin resistance is associated with an increase of TNF-α, IL-1α, IL-1β, IL-6, and leptin. Moreover, reduction of body's adipose tissue and weight loss account for part of the anti-inflammatory effects and for the impact of KD on cardiovascular health. In rheumatoid arthritis, fasting was shown to be effective in reducing disease symptoms, possibly through the production of β-hydroxybutyrate (BHB), the main ketone body. BHB may exert inhibitory effects also on IL-17 and intermittent fasting improved the clinical manifestations of psoriatic arthritis. In ankylosing spondylitis, current literature doesn't allow to draw conclusion about the effects of KD. Future prospective studies will be needed to elucidate the potential beneficial effects of KD on specific domains and clinical outcomes in patients with inflammatory arthritis.

Parameters of cutaneous microvasculature in men of working age with newly diagnosed arterial hypertension

OBJECTIVE

To investigate structural and functional features of cutaneous microvasculature in men of working age with newly diagnosed arterial hypertension (AH).

MATERIALS AND METHODS

The study included 161 apparently healthy men from 30 to 60 years, who underwent a comprehensive examination of cardiovascular system "from the heart to the capillaries". Control group (CG) included 60 normotensive men. AH group included 101 men with elevated BP.

RESULTS

There is no rarefaction of the capillary bed and latent fluid retention in the interstitial space in the skin in men with AH. No data were obtained for increased endothelial, neurogenic and myogenic tone of resistive cutaneous precapillary arterioles in AH group, but a decrease in the perfusion efficiency of the endothelial and myogenic mechanisms of tissue perfusion modulation was noted.

CONCLUSION

Obtained results allow making the assumption that metabolic disorders at the level of capillaries that are of a systemic nature prevail in men with the onset of AH.

Novel application of optical coherence tomography and capillaroscopy in psoriatic arthritis in relationship to psoriasis and hand osteoarthritis

Objectives

Nailfold video capillaroscopy (NVC) and angiographic optical coherence tomography (OCTA) have potential in diagnosing PsA and differentiating it from psoriasis vulgaris (PsO) and hand OA. We aimed to assess the diagnostic properties of NVC and OCTA in patients with PsA compared with patients with PsO and hand OA based on nailfold capillary patterns.

Methods

Patients with DIP joint PsA and nail involvement (n = 50), PsO with nail involvement (n = 12) and OA (n = 13) were included in this cross-sectional study. Capillaries were evaluated semi-quantitatively and qualitatively. Differences in capillary findings between groups were assessed using mixed linear models. Binary logistic regression analyses were performed to determine the probability for PsA diagnosis based on capillaroscopy findings.

Results

Below mean capillary density and reduced nailfold blood flow in OCTA images distinguished PsA from both PsO (P = 0.004 and P = 0.052, respectively) and OA (P = 0.024 and P < 0.001, respectively). Qualitative analysis revealed that glomerular capillaries were found in only 3% of PsA patients but in 13% of PsO patients (P = 0.003). Furthermore, crossed vessels were seen in only 55% of PsA patients and 71% of PsO patients (P = 0.043). NVC microhaemorrhage was dominant in PsA patients (13%) and significantly different from OA patients (P <0.05). No capillary pattern was associated with an increased probability of the PsA diagnosis.

Conclusion

A pathognomonic pattern for PsA diagnosis was not identified; however, we demonstrated some characteristic capillaroscopy findings for PsA, such as decreased capillary density, reduced blood flow and fewer crossed vessels in OCTA and presence of NVC microhaemorrhages.

Nailfold capillaroscopy and microvascular involvement in Diabetes Mellitus

Objective: to study the relationship between microvascular lesions of Diabetes Mellitus and alterations in the nailfold capillaroscopy. Subjects and Methods: cross-sectional study including 140 individuals (70 with Diabetes Mellitus and 70 controls). Epidemiological and clinical variables were collected from patient’s charts. Fundus ophthalmoscopy, nailfold capillaroscopy, analysis of microalbuminuria and renal clearance as well as fasting glycaemia and HbA1c values were studied simultaneously.Results: capillary density was reduced, and vascular dilatation was increased in Diabetes Mellitus patients when compared to controls (both with p<0.0001). In diabetic individuals the number of dermal papillary capillaries/mm3 correlated negatively with microalbuminuria (p=0.02), patient’s age (p=0.03), values of HbA1c (p=0.03). Patients with diabetic retinopathy and using antiplatelet agents had lower capillary density (p<0.0001 and 0.04 respectively). Capillary dilatation was associated with disease duration (p=0.04).Conclusion: microvascular disease in Diabetes Mellitus is reflected in nailfold capillaroscopy. Decreased capillary density, increased number of ectasias and increased presence of avascular areas were observed in patients with diabetes when compared to controls. In the present study, capillary density correlated/ associate with age, retinopathy, use of antiplatelet medication, HbA1c, microalbuminuria and diabetes duration. Ectasias or dilatations were related to retinopathy, glomerular filtration rate and longer disease duration.

Patients with Systemic Sclerosis with and without Overlap Syndrome Show Similar Microvascular Abnormalities

INTRODUCTION

Nailfold video capillaroscopy (NVC) is a useful tool for measuring capillary density (CD) and capillary morphology parameters and is mainly used in systemic sclerosis (SSc).

OBJECTIVE

We aimed to assess the prevalence of an SSc pattern and CD in different connective tissue diseases (CTDs).

METHODS

NVC was performed on 268 patients with CTDs. Control groups consisted of 104 healthy volunteers (HVs) and 36 primary Raynaud's patients (PRPs).

RESULTS

Decreased CD was more prevalent in SSc, systemic lupus erythematosus (SLE), inflammatory myopathies (IIM), and overlap CTD patients compared with both controls. Average CD, the prevalence of decreased CD, and the prevalence of an SSc pattern did not differ significantly between SSc patients with (n = 39) and without (n = 50) overlap syndrome. An SSc pattern was significantly more prevalent in SLE (23%), SSc (82%), IIM (35%), and rheumatoid arthritis (17%) compared with both control groups. The prevalence of an elevated microangiopathy evaluation score (MES) was significantly higher in SLE, SSc, and IIM than in the HVs.

CONCLUSION

The presence of another CTD in SSc did not influence CD or morphology. An SSc pattern may also be present in CTDs other than SSc. The MES is a useful instrument to distinguish between patients with CTDs and controls.

The effect of vitamin D3 and thyroid hormones on the capillaroscopy-confirmed microangiopathy in pediatric patients with a suspicion of systemic connective tissue disease-a single-center experience with Raynaud phenomenon

Raynaud phenomenon (RP) may be the first manifestation of a systemic connective tissue disease (SCTD). Early detection of dysfunction of small vessels called microangiopathy is essential for the diagnostic process. The focus of this single-center, retrospective study was to investigate the potential dependencies between microvascular image and laboratory markers measured in children with RP. The study analyzed the nail-fold video-capillaroscopy (NVC) findings and laboratory results of 81 children between the ages 6 and 17 who were referred to pediatric rheumatologist with a suspicion of SCTD. Out of 52 patients presenting with RP at the time of evaluation, abnormalities in capillary microscopic imaging were found in 34. NVC findings were then compared to levels of specific biomarkers in serum. Vitamin D3 serum levels have been significantly decreased in patients with RP (23.4 ng/mL ± 8.76 vs. 30.0 ng/mL ± 12.66, P = 0.0148). There were positive significant correlations between levels of vitamin D3 and acute-phase reactants in serum, such as C-reactive protein (P = 0.0292). Furthermore, free thyroxine levels (fT4) in patients with both RP (P = 0.0126) and micro-angiopathy (P = 0.05496) persisted in the lower range of the normal limit (< 1.0 ng/dL). Regular oral supplementation of vitamin D3 should be always considered in children with RP if deficiency is found. Additionally, low fT4 level (< 1.0 ng/dL) should be considered as an indication to perform NVC in patients suspected of SCTD even when they do not present RP.

Association of abdominal obesity with crossing capillaries in the finger nailfold in type 2 diabetes mellitus

Aim

Increased crossing of finger nailfold capillaries could be a novel visual marker of early microvascular damage among type 2 diabetes mellitus patients. Although abdominal obesity is an important driver of early microvascular damage, its association with an increase in the percentage of crossing capillaries remains uncertain. We investigated the association between abdominal obesity and an increase in the percentage of crossing capillaries in the finger nailfold in patients with type 2 diabetes mellitus.

Methods

This cross-sectional study enrolled 123 type 2 diabetes mellitus patients (age 40-75 years) who visited the outpatient diabetic clinic at Osaka University Hospital between May and October 2019. Abdominal obesity was defined as a waist circumference ≥ 90 cm in women and ≥ 85 cm in men. Capillary morphology was assessed by nailfold capillaroscopy based on the simple capillaroscopic definitions of the European League Against Rheumatism Study Group. The association between abdominal obesity and a high percentage of crossing capillaries in the finger nailfold (defined as the highest tertile of crossing capillaries) was analyzed using multivariable logistic regression.

Results

After adjusting for age, sex, smoking status, regular exercise, duration of diabetes, glycated hemoglobin, hypertension, and dyslipidemia, abdominal obesity was significantly associated with a high percentage of crossing capillaries (multivariable-adjusted odds ratios [95% confidence interval] = 2.70 [1.05-6.90], p = 0.038).

Conclusions

Abdominal obesity may play an important role in the increase in the percentage of crossing capillaries in the finger nailfold in patients with type 2 diabetes mellitus.

Nailfold capillaroscopy findings in patients with coronavirus disease 2019: Broadening the spectrum of COVID-19 microvascular involvement

OBJECTIVE

Increasing evidence points to endothelial dysfunction as a key pathophysiological factor in coronavirus disease-2019 (COVID-19). No specific methods have been identified to predict, detect and quantify the microvascular alterations during COVID-19. Our aim was to assess microvasculature through nailfold videocapillaroscopy (NVC) in COVID-19 patients.

METHODS

We performed NVC in patients with a confirmed diagnosis of COVID-19 pneumonia. Elementary alterations were reported for each finger according to a semi-quantitative score. Capillary density, number of enlarged and giant capillaries, number of micro-hemorrhages and micro-thrombosis (NEMO score) were registered.

RESULTS

We enrolled 82 patients (mean age 58.8 ± 13.2 years, male 68.3%) of whom 28 during the hospitalization and 54 after recovery and hospital discharge. At NVC examination we found abnormalities classifiable as non-specific pattern in 53 patients (64.6%). Common abnormalities were pericapillary edema (80.5%), enlarged capillaries (61.0%), sludge flow (53.7%), meandering capillaries and reduced capillary density (50.0%). No pictures suggestive of scleroderma pattern have been observed. Acute COVID-19 patients, compared to recovered patients, showed a higher prevalence of hemosiderin deposits as a result of micro-hemorrhages (P = .027) and micro-thrombosis (P < .016), sludge flow (P = .001), and pericapillary edema (P < .001), while recovered patients showed a higher prevalence of enlarged capillaries (P < .001), loss of capillaries (P = .002), meandering capillaries (P < .001), and empty dermal papillae (P = .006).

CONCLUSION

COVID-19 patients present microvascular abnormalities at NVC. Currently ill and recovered subjects are characterized by a different distribution of elementary capillaroscopic alterations, resembling acute and post-acute microvascular damage. Further studies are needed to assess the clinical relevance of NVC in COVID-19.