An imaging technique called nailfold videocapillaroscopy and a blood-based detection of systemic sclerosis (SSc) specific autoantibodies can provide helpful information for early diagnosis of the condition, according to two studies presented at the Annual European Congress of Rheumatology (EULAR) 2017, held June 14-17 in Madrid, Spain.
In the study titled, “Preliminary Analysis of Nailfold Capillaroscopy in the Very Early Diagnosis of Systemic Sclerosis (Vedoss): the Capi-Vedoss Experience,” researchers evaluated a total of 1,085 patients with Raynaud’s phenomenon — a condition in which people have episodes of reduced blood supply in the body’s extremities — from 40 different centers.
These patients were included in the Very Early Diagnosis of Systemic Sclerosis (VEDOSS) EUSTAR study. They were divided into two main groups (positive or negative), according to the presence in the blood of the commonly used SSc biomarker, antinuclear antibodies (ANA).
Taking advantage of the non-invasive nailfold videocapillaroscopy technique, the researchers could visualize structural changes in the peripheral small vessels in patients with early SSc patterns.
“Because SSc is usually preceded by the presence of Raynaud’s phenomenon, this provides an ideal opportunity to investigate the earliest damage to the microcirculation,” lead author Professor Vanessa Smith from Ghent University Hospital, Belgium, said in a press release.
The researchers found that disruption of the normal capillary net detected by nailfold videocapillaroscopy in early SSc patients was higher in the ANA-positive patients (40%) compared to those who were ANA-negative (13%). In addition, a typical “early” pattern of vessels alteration was present in 79% of the patients with SSc.
“Nailfold videocapillaroscopy should be regarded as a key component of the VEDOSS criteria (that also encompass clinical changes to the microcirculation “Raynaud’s phenomenon,” presence of antinuclear antibodies in the circulation and puffy digits), which have been specifically designed to diagnose SSc as early as possible,” Smith said.
“One of the aims of studying the disease in such an early cohort is to find targets to ultimately treat the disease before irreversible tissue damage has occurred,” Smith added.
In the second study presented at the 2017 EULAR congress, titled “Development of a Novel Epitope-Based Diagnostic Assay for Systemic Sclerosis,” researchers from Italy presented a new technique they developed that uses a blood test that could specifically identify an SSc-specific small molecule (PDGFRα) to detect and diagnose the disease.
After screening 25 blood samples from SSc patients — 12 with limited SSc, 13 with diffuse SSc, and 25 from healthy controls — researchers identified what they called an “immunodominant peptide,” a small protein fragment that was only found in SSc patients and not in controls.
In addition, they found that detection of this specific peptide was restrictive to patients with active, progressive disease, whereas those with less active, non-progressive disease would not react to the peptide.
“Our preliminary results suggest that this new blood test to detect SSc-specific, agonistic, autoantibodies may identify those SSc patients with active disease, regardless of the ‘limited vs diffuse’ extension of their disease,” said lead author Gianluca Moroncini from Università Politecnica Marche, in Italy.
“Although we have initial data on the specificity of the test i.e. its ability to discriminate between SSc patients with active disease from patients with inactive disease, no data are available as yet on early diagnosis. The VEDOSS cohort would be an ideal target for assessing the utility of this new test in the early identification of active / progressive forms of SSc,” Moroncini added.
The team suggested that more studies confirming the effectiveness of this new blood test in larger cohorts should be conducted to validate it as a diagnostic tool.
Both these studies provide further support for the newly launched EULAR campaign, “Don’t delay, connect today.” This EULAR initiative aims to spread awareness for the benefits of early diagnosis and access to treatment for rheumatic and musculoskeletal diseases.