Associations between nailfold capillaroscopy findings and interstitial lung disease in patients with mixed connective tissue disease

Evolution of diagnostic criteria and new insights into clinical testing in mixed connective tissue disease; anti-survival motor neuron complex antibody as a novel marker of severity of the disease

Mixed connective tissue disease (MCTD) is an autoimmune disorder characterized by a combination of clinical features from systemic lupus erythematosus, systemic sclerosis, and inflammatory muscle disease, along with the presence of positive anti-U1-ribonucleoprotein (U1-RNP) antibodies. The exact etiology of the disease remains unclear, but it is believed to involve vascular damage within the context of heightened autoimmune responses. Consequently, Raynaud's phenomenon and pulmonary arterial hypertension are observed in patients with MCTD. While specific biomarkers for MCTD have not yet been identified, the recent study of the utility of anti-survival motor neuron complex (SMN) antibodies in MCTD suggests a promising avenue for further research and the accumulation of additional evidence.

Naifold capillaroscopy in mixed connective tissue disease patients

INTRODUCTION

Mixed connective tissue disease (MCTD) is a rare systemic disease characterized by overlapping features of systemic lupus erythematosus (SLE), systemic sclerosis (SSc), dermato-/polymyositis (DM/PM), and rheumatoid arthritis (RA). Naifold capillaroscopy (NFC) is a non-invasive test for evaluating the capillaries of the nail shaft used in the diagnosis of rheumatic diseases.

OBJECTIVES

To determine whether there are characteristic abnormalities in NFC in MCTD patients, and whether the type of NFC lesions correlates with organ involvement in these patients.

METHODS

Clinical picture and NFC patterns were analyzed in 43 patients with MCTD. Capillaroscopic images were divided into scleroderma-like pattern (SD-like pattern) according to the Cutolo classification, non-specific lesions, and normal images. Relationships between the clinical aspects considered in the MCTD classification criteria and the changes in the capillaroscopic images were evaluated.

RESULTS

SD-like pattern was present in 20 MCTD patients (46.51%) with a predominance of the "early" pattern. Giant, branched, dilated capillaries and reduced capillary density were found more frequently in MCTD patients compared to the control group (p-values 0.0005, 0.005, 0.02, < 0.0001 respectively). There were associations found between the presence of a reduced number of vessels, avascular areas, and SD-like pattern with the presence of sclerodactyly in MCTD patients (p = 0.002, p = 0.006, p = 0.02, respectively), alongside an association between the presence of branched vessels and the subpapillary plexus with pulmonary arterial hypertension (PAH) (p = 0.04 and p = 0.005, respectively).

CONCLUSIONS

MCTD patients are significantly more likely to have abnormalities upon NFC. It is worthwhile to perform capillaroscopic examination in MCTD patients. Key Points • Scleroderma-like pattern was found in more than half of the MCTD patients. • Reduced capillary density was found to be a significant predictor of the diagnosis of MCTD. • There were relationships between the presence of reduced capillary density, avascular areas, and SD-like with the presence of sclerodactyly in the MCTD patients. • There was an association between the presence of branched vessels and the visibility of the subpapillary plexus and pulmonary arterial hypertension (PAH).

The Role of Nailfold Capillaroscopy in Evaluating Patients with Interstitial Lung Disease Related to Connective Tissue Disease

Capillaroscopy is a non-invasive and safe imaging method that allows the evaluation of the microcirculation of the small vessels of the skin. The method's main advantage is the early detection of microvascular changes that may occur in certain connective tissue diseases (CTDs). Today, the presence of specific autoantibodies and capillaroscopic findings are generally accepted and emerge as a powerful diagnostic tool for detecting underlying CTDs in patients with Raynaud's phenomenon. The role of capillaroscopy has also been investigated in patients with CTD and interstitial lung disease (ILD). In these patients, lung involvement is considered one of the most severe complications, potentially leading to significant morbidity and mortality. So far, studies have shown an association of the scleroderma pattern in capillaroscopy with lung involvement in Scleroderma patients. Although there are studies on the association of capillary findings in patients with other CTDs, further efforts are needed to evaluate this technique and produce high-performance algorithms in the early detection of involvement and the progression of (CTD) related ILD (CTD-ILD). The present study aims to perform capillaroscopy in CTDILD patients with different imaging patterns and to correlate the method's findings with those found in high-resolution computed tomography, pulmonary tests, and the immunological profile of patients. Furthermore, the impact of ILD treatment on the capillaroscopic findings will be evaluated.

Nailfold capillaroscopy

Nailfold capillaroscopy is a safe and well-established method for the assessment of structural alterations of the microcirculation. It is a crucial tool in the investigation and monitoring of patients presenting with Raynaud's phenomenon. Detection of the characteristic "scleroderma pattern" on capillaroscopy may indicate an underlying rheumatic disease, particularly systemic sclerosis (SSc). Herein, we highlight the practical aspects of videocapillaroscopy, including image acquisition and analysis, with mention of dermoscopy. Special emphasis is placed on standardized use of terminology to describe capillary characteristics. Systematic evaluation of images in discerning the normal from the abnormal using the validated European Alliance of Associations for Rheumatology (EULAR) Study Group consensus reporting framework is paramount. In addition to the relevance of capillaroscopy in the (very) early diagnosis of SSc, its emerging predictive value (especially capillary loss) for new organ involvement and disease progression is underscored. We further provide capillaroscopic findings in selected other rheumatic diseases.

Nailfold microvascular abnormalities are associated with a higher prevalence of pulmonary arterial hypertension in patients with MCTD

OBJECTIVE

MCTD manifests with microvasculopathy and overlapping clinical features of SLE, SSc and idiopathic inflammatory myopathies (IIM). The aim of this study was to investigate the clinical significance of microvasculopathy in patients with MCTD using nailfold videocapillaroscopy (NVC).

METHODS

Fifty patients with newly diagnosed and untreated MCTD were enrolled in this multicentre, prospective and observational study. Clinical features and NVC findings were assessed at baseline and after 1 year post-intervention, along with disease controls [SLE (n = 40), SSc (n = 70) and IIM (n = 50)].

RESULTS

All MCTD patients presented Raynaud's phenomenon and were positive for anti-U1 RNP antibodies, and 22.0% (11/50) had pulmonary arterial hypertension (PAH). The prevalence of NVC scleroderma patterns in MCTD was 38.0%, which was lower than SSc (88.6%) but higher than SLE (10.0%). In addition, when we divided MCTD patients into two groups by presence or absence of NVC scleroderma patterns, we found a higher prevalence of PAH in patients with NVC scleroderma patterns. Namely, NVC scleroderma patterns were observed in all MCTD patients with PAH, and in 21.0% of those without PAH. After intensive immunosuppressive therapy, NVC scleroderma patterns disappeared in half of the MCTD patients but were not changed in SSc patients.

CONCLUSIONS

MCTD differed from SLE, SSc and IIM in terms of the prevalence and responsiveness of NVC scleroderma patterns to immunosuppressive therapy. Detection of nailfold microvascular abnormalities in MCTD could contribute to predicting PAH and help us to understand further aspects of the pathogenesis of MCTD.

Relationship between type of skin lesions and nailfold capillaroscopy pattern in mixed connective tissue disease

INTRODUCTION

Mixed connective tissue disease (MCTD) is a rare disease with clinical picture consisted of multiple organ manifestations, including skin changes resembling systemic lupus erythematosus (SLE), systemic sclerosis (SSc), or dermatomyositis (DM). On the background of these manifestations are microvascular changes - alteration of endothelial function and impairment of endothelial progenitor cell. Nailfold capillaroscopy (NFC) is a simple, non-invasive technique for investigating microvascular involvement in rheumatic diseases.

OBJECTIVES

To describe the relationship between type of skin lesions and NFC pattern in MCTD patients.

METHODS

We analyzed the clinical picture and NFC patterns in 79 patients with MCTD. The NFC changes were classified into Normal, "Early," "Active," and "Late" scleroderma-like patterns (SD-like pattern) based on Cutolo classification. In all patients, subjective and physical examinations were carried out, specifically the occurrence of skin lesions in the course of MCTD was assessed (systemic sclerosis-like (Ssc-like), systemic lupus erythematosus-like (SLE-like), dermatomysitis-like (DM-like)).

RESULTS

Skin changes were present in 64 (81%) patients, involving 43 (54%) SLE-like, 48 (61%) SSc-like, and 4 (5.1%) DM-like. NFC changes were observed in a total of 55 (69.6 %) patients with predominance of the "Early" pattern - 41 (51.9 %) patients. According to skin change phenotypes, NFC changes were observed in 31 (72%) patients with SLE-like and in 32 (66.7%) patients with SSc-like skin phenotypes. The "early" pattern predominated in both group.

CONCLUSIONS

We did not find any correlation between NFC pattern and the type skin changes. Key Points • The study did not show a correlation between the presence and absence of skin lesions and NFC pattern. • Scleroderma-like patterns were found in over 60% of patients with mixed connective tissue disease. • The "early" pattern is dominant regardless of the occurrence or absence of skin lesions in patients with MCTD. • Skin lesions, regardless of their type (SLE or SSc), do not correlate with type of lesion found in the NFC examination.

Assessing the Role for Nailfold Videocapillaroscopy in Interstitial Lung Disease Classification: A Systematic Review and Meta-Analysis

OBJECTIVES

The nailfold videocapillaroscopy (NVC) has been known to assist with Interstitial Lung Disease (ILD) classification. However, evidence on its diagnostic efficacy is limited, particularly in some connective tissue disease-related interstitial lung diseases (CTD-ILD), and in interstitial pneumonia with autoimmune features (IPAF). This study aimed to address this limitation by conducting a meta-analysis on the efficacy of the NVC in ILD subgroups of CTD-ILD, IPAF and idiopathic pulmonary fibrosis (IPF).

METHODS

MEDLINE, EMBASE, CENTRAL were screened from inception to December 2020 according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Studies that report prevalence of nailfold abnormalities (NVC+) in CTD-ILD, IPAF and IPF cohorts were included. Data were presented as prevalence ratio (PR) with 95% CI using a random-effects model. Quality of evidence was assessed using GRADE criteria.

RESULTS

Twenty one studies were eligible. Prevalence of NVC+ was highest in CTD-ILD; PR [95 CI%] 80.4% [74.3%, 85.3%], followed by IPAF; 27.4% [10.9%, 53.7%], and IPF; 13.8% [5.7%, 29.9%]. Late Scleroderma pattern was the most prevalent nailfold pattern; 40.4% [28.1%, 54.1%] in our CTD-ILD cohort. Quality of evidence was low for CTD-ILD, IPAF and IPF cohorts, moderate for the Late Scleroderma Pattern cohort.

CONCLUSION

NVC can increase the diagnostic accuracy of ILD when used in a multi-disciplinary setting, and appears to have greatest utility in CTD-ILD, followed by IPAF and IPF. The Late Scleroderma Pattern was the most frequent nailfold capillary pattern in SSc-ILD. Future research will allow for greater understanding of the prognostic value of the NVC in ILD.

Nailfold capillaroscopy in systemic diseases: short overview for internal medicine

Nailfold capillaroscopy (NFC) is now one of the main imaging tools in systemic sclerosis and imposed over time as an easy, non-invasive method for the nailfold microvascular bed assessment. In qualitative NFC normal pattern is characterized by homogeneous, parallel fashion arrangement of the last capillaries row as well as by capillaries with hairpin or non-specific variations like tortuous and/ or crossing shape. Nailfold capillaroscopy is strongly recommended for evaluation of all patients with Raynaud phenomenon. Appearance of giant capillaries is chronologically the first relevant finding for scleroderma spectrum disorders development (systemic sclerosis, dermatomyositis, undifferentiated and mixed connective tissue disease). Collapses of the giant loops generate microhemorrhages and further capillary loss with subsequent hypoxia, and neoangiogenesis seen as ramified/ bushy capillaries. Nailfold capillaroscopy is indicated especially in systemic sclerosis, being also included in the classification criteria. Based on these major NFC pathologic findings (giant capillaries, microhemorrhages, avascularity and neoangiogenesis), three evolutive stages were described in systemic sclerosis, namely the early, active, and late scleroderma pattern. In other connective tissue diseases than those scleroderma-related, like systemic lupus erythematosus, psoriatic arthritis, or antiphospholipid syndrome, the interest for capillaroscopy is growing, but the attempts of defining specific characteristics failed until now. Besides qualitative NFC, semiquantitative and quantitative capillaroscopic assessments were proposed for more accurate evaluation. Lately, automated systems are under development. There is still need of more studies to sustain the nailfold capillaroscopy validity as diagnostic and prognostic test.

Microvascular damage - a marker of specific organ involvement in mixed connective tissue disease?

Mixed connective tissue disease (MCTD) is a complex entity, which incorporates features of systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), systemic sclerosis (SSc) and polymyositis/dermatomyositis (PM/DM). Nailfold videocapillaroscopy (NVC) is a simple, safe and non-invasive technique of capillary vessel assessment, allowing for qualitative and quantitative assessment of microcirculation. NVC plays a pivotal role in the diagnostic algorithm of connective tissue diseases, especially in systemic sclerosis (SSc). Numerous studies have shown a correlation between organ involvement and disease progression in SSc.

In the current literature, there are limited data on relationship between NVC and organ involvement in MCTD patients. In the present article the relevant literature describing NVC examination in patients with MCTD and comparisons with some clinical situations are discussed.

Capillaroscopy as a diagnostic tool in the diagnosis of mixed connective tissue disease (MCTD): a case report

BACKGROUND

The concept of mixed connective tissue disease (MCTD) as a unique connective tissue disease has endured for half a century. Disease onset can be in adulthood (MCTD) or of juvenile onset (jMCTD) and is characterized by overlapping features of systemic lupus erythematosus (SLE), polymyositis or dermatomyositis (PM/DM) and systemic sclerosis (SSc). No universally accepted classification criteria for MCTD exists, however agreed upon overlapping disease features include the presence of high titers of U1 small nuclear ribonucleoprotein particle antibodies (U1snRNP) in the peripheral blood, Raynaud's phenomenon, synovitis, myositis and swollen hands or fingers. Characteristic capillaroscopy findings are commonly seen in MCTD and jMCTD, which may represent a crucial and key clue for classification as well as prognosis in these patients.

CASE PRESENTATION

We present a young male patient, with symptom onset as early as age 13, who was diagnosed with MCTD at age 16 and found to have high titers of anti-U1snRNP antibodies, Raynaud's phenomenon, synovitis, and swollen hands and fingers. Most interestingly, his video capillaroscopy at diagnosis was abnormal and revealed an active SSc-like pattern. His presentation and course are described.

CONCLUSIONS

We conclude that based on existing data, and as highlighted by this case presentation, nailfold video capillaroscopy should be included as an early screening tool for the detection of microangiopathy in patients with the diagnosis MCTD and jMCTD. Additionally, given its prevalence in this population at disease diagnosis, we recommend consideration be given to nailfold video capillaroscopy as a potentially important classification criteria and prognostic tool for jMCTD and MCTD.