Background/Purpose

Systemic Sclerosis (SSc) is a connective tissue disease characterized by Raynaud’s phenomenon, skin fibrosis and involvement of internal organs such as lung, heart, bowel, and kidney. The microvascular involvement is considered an hallmark of disease. Nailfold Videocapillaroscopy (NVC) is a simple method able to identify the disease-related microvascular alterations in an easily accessible capillary bed and is commonly used for diagnosis and patients’ sub-setting.

Aim of this study is to evaluate whether the number of micro-haemorrhages (MHE), micro-thrombosis (MT), giant capillaries (GC), and normal or dilated capillaries (Cs) in NVC could predict disease activity (DA) in SSc.

Methods

One hundred and seven patients (57 with limited cutaneous and 50 with diffuse cutaneous SSc, 10 males) meeting the 2013 ACR/EULAR classification criteria, were selected for this study. The European Scleroderma Study Group (ESSG) index was taken as gold standard for DA assessment. Score ≥3.5 and =3 were considered as indicative of highly and moderate DA, respectively. NVC was performed on 8 fingers (second to fifth of both hand) in the middle of nailfold taking 4 consecutive fields of 1 millimeter with a 200x magnification lens. The following NVC features were considered: total number of MHE/MT aligned in the same row on the cuticle (here called NEMO score); total number of GC (GC score); mean number of Cs observed in all NCV fields (Cs score).

Non-parametric tests were used to compare the NVC scores with the variables here taken into account. Receiver operating characteristic (ROC) curves were constructed  by plotting sensitivity and specificity values of NVC scores in correctly classifying patient having or not an active disease phase. Logistic regression model was also tested to assess the contribution of the NVC scores in predicting the presence of DA.

Results

NEMO and GC scores were positively correlated with ESSG index  (R=0.65, p<0.0001, and R=0.47, p<0.0001, respectively), whilst Cs score showed a negative correlation with that DA index (R=-0.30, p<0.001).

The area under the curve (AUC) of receiver operating characteristic (ROC) plots, obtained by NEMO score sensitivity and specificity values in classifying patients with ESSG index ≥3.5,  was significantly higher than the corresponding AUC derived from either GC or Cs scores  (p<0.001 and p<0.0001, respectively). A modified score, defined by the presence of given number of MHE/MT and GC, had a good performance in classifying active patients (ESSG index ≥ 3, sensitivity 95.1%, specificity 84.8%, accuracy 88.7%).

Conclusion

This newly proposed NCV scoring system, here named mNEMO score, seems to be a valid tool to predict DA level in SSc. In addition, it appears also feasible since it can be derived simply during an outpatient visit and in a rather short time.

It is, of course, evident that a patient with a positive mNEMO score should be addressed to a more careful clinical, instrumental, and serological evaluation to confirm the suspicion and define a more precise clinical profile.

ACR Meeting Abstracts - https://acrabstracts.org/abstract/microhaemorrages-and-giant-capillaries-in-nailfold-videocapillariscopies-are-able-to-accurately-predict-disease-activity-level-in-systemic-sclerosis/