Longitudinal study of microvascular involvement by nailfold capillaroscopy in children with Henoch-Schönlein purpura

Nailfold Capillaroscopy Analysis Can Add a New Perspective to Biomarker Research in Antineutrophil Cytoplasmic Antibody-Associated Vasculitis

BACKGROUND

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) includes granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (EGPA), all of which are characterised by inflammation of small-medium-sized vessels. Progressive understanding of these diseases has allowed researchers and clinicians to start discussing nailfold video capillaroscopy (NVC) as a future tool for many applications in daily practice. Today, NVC plays a well-established and validated role in differentiating primary from secondary Raynaud's phenomenon correlated with scleroderma. Nevertheless, there has not been sufficient attention paid to its real potential in the ANCA-associated vasculitis. In fact, the role of NVC in vasculitis has never been defined and studied in a multicentre and multinational study. In this review, we carried out a literature analysis to identify and synthesise the possible role of capillaroscopy for patients with ANCA-associated vasculitis.

METHODS

Critical research was performed in the electronic archive (PUBMED, UpToDate, Google Scholar, ResearchGate), supplemented with manual research. We searched in these databases for articles published until November 2023. The following search words were searched in the databases in all possible combinations: capillaroscopy, video capillaroscopy, nailfold-video capillaroscopy, ANCA-associated vasculitis, vasculitis, granulomatosis with polyangiitis, EGPA, and microscopic polyangiitis.

RESULTS

The search identified 102 unique search results. After the evaluation, eight articles were selected for further study. The literature reported that capillaroscopy investigations documented non-specific abnormalities in 70-80% of AAV patients. Several patients showed neoangiogenesis, capillary loss, microhaemorrhages, and bushy and enlarged capillaries as the most frequent findings. Furthermore, the difference between active phase and non-active phase in AAV patients was clearly discernible. The non-active phase showed similar rates of capillaroscopy alterations compared to the healthy subjects, but the active phase had higher rates in almost all common abnormalities instead.

CONCLUSIONS

Microvascular nailfold changes, observed in patients affected by vasculitis, may correlate with the outcome of these patients. However, these non-specific abnormalities may help in the diagnosis of vasculitis. As such, new analysis analyses are necessary to confirm our results.

Nailfold videocapillaroscopy in antineutrophil cytoplasmic antibody-associated vasculitis

OBJECTIVE

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a group of illnesses that cause inflammation and alterations to small vessels in the body. Some of the most common and detrimental manifestations, including alveolar hemorrhage and glomerulonephritis, are caused by this capillary inflammation. We sought to clarify whether patients with AAV would have abnormal nailfold capillaries when evaluated with nailfold videocapillaroscopy.

METHODS

Patients with a current diagnosis of AAV and a control group were identified for enrollment. Nailfold videocapillaroscopy images were used for a semiquantitative analysis on capillary density, morphology, dilation, and microhemorrhage after review by 2 rheumatologists. Disease characteristics, occurrence of recent disease flare, and presence of ANCA were recorded.

RESULTS

Thirty-three patients with a diagnosis of AAV and 21 controls were recruited. The AAV group had a median age of 59 and 17 (52%) were women. Granulomatosis with polyangiitis was the most common diagnosis (19 [58%]), followed by eosinophilic granulomatosis with polyangiitis (7 [21%]) and microscopic polyangiitis (7 [21%]). Twenty-seven patients (82%) had positive ANCA tests. After assessment of capillary density, dilation, morphology, microhemorrhages, and disorganization, there were no statistically significant differences between the 2 groups.

CONCLUSION

There was no evidence of differences in nailfold capillaroscopy abnormalities between those diagnosed with AAV and the control group. While this cohort was relatively small, we did not find a high enough prevalence or specific phenotype of capillary abnormalities that could aid in diagnosis or prognostication of these diseases in the clinical setting.

Nailfold capillaroscopy reveals early peripheral microcirculation abnormalities in children affected by heterozygous familial hypercholesterolemia

BACKGROUND

nailfold capillaroscopy (NCF) is a non-invasive imaging technique to seek peripheral microcirculation abnormalities in children and adults. Familial hypercholesterolemia is a genetic disorder caused by mutations capable of increasing blood levels of low-density lipoproteins cholesterol (LDL-C), thus triggering early atherosclerosis. The study aims at evaluating peripheral microcirculation in children with heterozygous familial hypercholesterolemia (HeFH) by means of NFC in comparison with healthy peers and at searching for possible correlations between these abnormalities and patients' lipid panel.

METHODS

thirty-six HeFH patients were enrolled (13 males and 23 females. Mean age 8 ± 3 years; age range 3-13 years). They had increased levels of total cholesterol (237.9 ± 34.2 mg/dl) and LDL-C (154.2 ± 37.6 mg/dl). Both values were ≥95th gender and age specific centile. All the subjects in the study underwent NFC.

RESULTS

In 69.4 % of HeFH children nailfold capillaries were tortuous (p < 0.00001 compared to healthy controls). In 41.6 % the number of capillaries was markedly reduced (<7 capillaries/mm). The mean number of capillaries was 8.4 ± 2.6/mm in HeFH and 12.2 ± 1.4/mm in healthy controls (p < 0.00001). In 100 % of the sample size capillary blood flow was slowed down (p < 0.00001). In 50 % of the sample size a blood "sludge" phenomenon was seen (p < 0.00001). No gender differences were detected. Sludge phenomenon was seen only in those with LDL-C over 99th centile (p < 0.00001).

CONCLUSION

NCF allows the identification of an early peripheral microvascular dysfunction in HeFH children which is similar to that already seen in atherosclerotic disease. Prompt identification of these capillary abnormalities may be crucial in implementing early prevention measures.

Examination of nailfold videocapillaroscopy findings in ANCA-associated vasculitis

OBJECTIVE

The objective of this study was to evaluate nailfold videocapillaroscopy (NVC) as a useful tool for assessing the disease activity of ANCA-associated vasculitis (AAV).

METHODS

This study enrolled 51 patients with AAV and 21 healthy controls. We scored NVC findings semiquantitatively, and compared them between AAV patients and controls. We examined the association of NVC findings with disease activity indicators, histopathological findings of skin biopsies, and high-resolution CT (HRCT) scores in AAV. Additionally, we repeatedly rated the NVC findings 3 months after immunosuppressive therapy.

RESULTS

Of the 51 enrolled patients, 36 (70.6%) showed a microangiopathy pattern and 4 (7.8%) showed a scleroderma pattern in AAV. The scores for microhaemorrhage, capillary loss, neoangiogenesis, and tortuosity were significantly higher in the AAV group than in the control group. NVC abnormalities correlated with the severity of skin, lung and kidney involvement. The scores of giant capillaries significantly correlated with the total BVAS and the chest BVAS; the scores of capillary loss correlated with the chest BVAS and the renal BVAS. The scores of microhaemorrhage significantly correlated with perivascular inflammatory cell infiltrations in the upper dermis of the purpura and tended to correlate with the total ground-glass opacity and consolidation scores on HRCT. In addition, capillary loss scores had a significant positive correlation with serum creatinine levels. Additionally, the microhaemorrhage scores were significantly reduced after 3 months of immunosuppressive therapy.

CONCLUSION

In AAV patients, NVC abnormalities are significantly associated with disease severity. This result suggests that NVC is a useful tool for assessing the disease activity and treatment response in AAV.

Nailfold video capillaroscopy as a useful diagnostic tool in systemic vasculitis

BACKGROUND

Nailfold video capillaroscopy (NVC) enables us a direct view of the microvasculature. Only several capillaroscopy studies in adult patients with vasculitis have been reported.

AIM

To characterize NVC changes in vasculitis.

METHODS

Vasculitis patients and healthy controls were evaluated by NVC. NVC changes associated with vasculitis were assessed retrospectively in a cohort of 100 patients with Raynaud's phenomenon (RP).

RESULTS

17 patients with active vasculitis and 8 patients with vasculitis in remission were compared to 25 age and sex-matched healthy controls. Active vasculitis patients demonstrated higher rates of neoangiogenesis and capillary loss in comparison to other groups. Two novel NVC abnormalities were observed in patients with vasculitis: "Rolling" (slow capillary flow) and "peri-capillary stippling" (PCS), small deposits that may represent capillary leak. PCS was observed exclusively in 5 of 17 patients with active vasculitis. Retrospectively, we were able to detect PCS also in 14 % of 100 patients that were evaluated for RP, of whom 64 % were diagnosed with scleroderma or a related disorder.

CONCLUSIONS

Patients with active vasculitis demonstrate frequent capillary abnormalities. Although these abnormalities are non-specific, we suggest that their combination may aid the diagnosis of vasculitis. Future studies are needed to validate our findings.

Association between nailfold capillaroscopy abnormalities and autoimmune disease in pediatric populations

OBJECTIVE

Time to diagnosis of autoimmune disease in pediatric populations can take years but nailfold capillaroscopy (NFC) may identify early signs of autoimmune disease. The aim of this study is to assess the association between nailfold capillary abnormalities and autoimmune disease in children.

METHODS

A systematic search of PubMed, EMBASE, and Scopus was performed to identify all studies published before March 17, 2021. Observational studies reporting NFC outcomes in children with autoimmune disease and healthy controls (HC) were eligible for inclusion. Odds ratios (OR) and 95% confidence intervals (CI) were pooled using a random-effects meta-analytical model.

RESULTS

Nine of 3665 studies reporting on 641 patients (398 subjects, 243 controls) were included. Pediatric patients with autoimmune disease were 9.88 (95% CI 3.16-30.87, I²  = 80.1%) times more likely to have abnormal nailfold capillaries than HC. Of the capillaroscopic features, dilated capillaries (OR 27.90, 95% CI 2.17-349.05, I²  = 59.9%) were the most likely abnormality observed on NFC. This was followed by the likelihood of reduced capillary density (<7 capillaries/mm) (OR 19.91, 95% CI 3.79-105.52, I²  = 0%), giant capillaries (OR 12.87, 95% CI 2.38-69.45, I²  = 0%), hemorrhages (OR 13.89, 95% CI 5.34-36.16, I²  = 0%), and avascularity (OR 10.38, 95% CI 2.20-49.04, I²  = 0%).

CONCLUSIONS

Children with autoimmune disease are significantly more likely to have nailfold capillary abnormalities. NFC may be useful in identifying early signs of underlying rheumatic disease and potentially decrease the time to diagnosis for this patient population.

Nail-fold capillaroscopy for the dermatologists

Nail fold is one of the most accessible sites for studying changes in the microcirculation in various microangiopathies. The characterization of changes in microvasculature can provide useful clues towards the diagnosis and prognosis of a disease. The diagnostic utility of nail fold capillaroscopy has improved and expanded over the past couple of decades. Beyond connective tissue diseases, it is now explored for its role in various systemic and dermatological diseases. Incorporation of nail-fold capillaroscopy in the diagnostic criteria of systemic sclerosis has generated interest among dermatologists. The current review is aimed at providing knowledge about nail-fold capillaroscopy to dermatologists. For the purpose of review, a PubMed search was done using the keywords "nail fold capillaries" and "nail fold capillaroscopy". All the articles were retrieved and classified into reviews and clinical studies of various types. The final data were then analyzed and presented in a narrative fashion.

Nail disorders as signs of pediatric systemic disease

Herein, we describe some of the more common changes in the nail unit that can be seen in systemic diseases in children. Changes that can be seen are not limited to those discussed in the following pages. The presence of changes on multiple nails is suggestive of a systemic cause in an ill child. However, multiple nails can also be affected in primary inflammatory disorders and infections of the nail unit. When evaluating a pediatric patient with a nail disorder, it is important to perform a complete physical examination of the skin and oral mucosa, as other clues to the diagnosis of the nail problem may be found. A comprehensive family history is also important to uncover possible syndromic associations with nail disease or diseases that can manifest with nail changes.

Correlation mapping method for generating microcirculation morphology from optical coherence tomography (OCT) intensity images

Standard optical coherence tomography (OCT) in combination with software tools can be harnessed to generate vascular maps in vivo. In this study we have successfully combined a software algorithm based on correlation statistic to reveal microcirculation morphology on OCT intensity images of a mouse brain in vivo captured trans-cranially and through a cranial window. We were able to estimate vessel geometry at bifurcation as well as along vessel segments down-to mean diameters of about 24 μm. Our technique has potential applications in cardiovascular-related parameter measurements such as volumetric flow as well as in assessing vascular density of normal and diseased tissue.

Update in paediatric vasculitis

Vasculitis refers to a heterogeneous group of disorders that are characterised by inflammatory destruction of blood vessels. Although simple to define, almost nothing about vasculitis is simple. From classification to diagnosis, and from pathogenesis to management, large gaps remain in our understanding. Despite extensive and ongoing research, the fundamental mechanisms underlying the initiation and continuation of systemic vasculitis remain poorly understood. Thus, vasculitis continues to provide tremendous challenges to both clinicians and investigators and remains a rich source of issues for discussion. This review concentrates on recent changes proposed for the classification of paediatric vasculitis and advances in the concepts of aetiopathogenesis. Availability of improved classification criteria for children should prompt planning for multicentre-controlled studies for the treatment of these rare but important diseases.