THU0357 NAILFOLD CAPILLARY MICROSCOPY HAS LIMITED PROGNOSTIC VALUE IN PREDICTING FUTURE DEVELOPMENT OF CONNECTIVE TISSUE DISEASE IN CHILDREN WITH RAYNAUD’S PHENOMENON.
Authors: G. Van der Kamp, D. J. Mulder, A. Van Roon, A. Van Roon, A. Van Gessel, W. Armbrust
Journal: Annals of the Rheumatic Diseases (2020)

Background: For adults with Raynaud’s phenomenon (RP), nailfold capillary microscopy (NCM) is established to be an effective method for differentiating between PRP and SRP (1,2). Although Raynaud’s phenomenon (RP) is very common in childhood, studies on diagnostic methods to differentiate between primary RP (PRP) and secondary RP (SRP) at a young age are scarce (3,4). Objectives: The general aim of this study was to determine the prognostic value of nailfold capillary microscopy (NCM) in addition to antinuclear antibodies (ANAs) for later development of connective tissue diseases (CTD) in children with RP. Methods: This was a case-control study, in which 83 patients diagnosed with RP and having undergone NCM in childhood were retrospectively included. Based on whether they were diagnosed with a connective tissue disease (CTD) during follow-up, they were classified as PRP or SRP. PRP and SRP patients were compared on demographics, NCM and ANA positivity. Variables associated with SRP were included in a multivariate logistic regression model. Predictive values were calculated for NCM, ANA positivity and the combination of NCM and ANA positivity. Results: At the time of the baseline NCM, the mean age of the RP patients was 15.4±2.3 years. Averagely 6.4±3.2 years after the baseline NCM, 65 of the 83 patients were classified as PRP and 18 as SRP. The most common CTDs were MCTD and undifferentiated CTD. ANA positivity was associated with SRP (p&lt;0.001). Of the NCM parameters, only capillary loss was associated with SRP (p=0.01). Abnormal numbers of dilated capillaries, giant capillaries and haemorrhages were not significantly associated with SRP. In a multivariate logistic regression model, only ANA positivity was predictive for SRP (OR 11.19, CI 3.07-40.79). ANA alone had a sensitivity of 66.7% and a specificity of 85.9% for SRP. ANA combined with capillary loss had a sensitivity of 33.3% and a specificity of 96.8%. Conclusion: This study demonstrates that childhood RP is primary in most cases. Whereas RP in adulthood is most strongly associated with SSc, children with RP seem to be at risk of developing other CTDs with less apparent NCM abnormalities. Dilated capillaries, giant capillaries and haemorrhages on NCM are not associated with the spectrum of CTDs that children are at risk for, and do not differentiate between primary and secondary RP. Although capillary loss on NCM is associated with SRP, capillary loss may add little to the predictive value of serology. To clarify which NCM parameters are helpful for early detection of SSc-like CTDs, additional research is required. References: [1]Koenig M, Joyal F, Fritzler MJ, Roussin A, Abrahamowicz M, Boire G, et al. Autoantibodies and microvascular damage are independent predictive factors for the progression of Raynaud’s phenomenon to systemic sclerosis: A twenty-year prospective study of 586 patients, with validation of proposed criteria for early systemic sclerosis. Arthritis Rheum. 2008;58(12):3902–12. [2]Pavlov-Dolijanovic S, Damjanov NS, Stojanovic RM, Vujasinovic Stupar NZ, Stanisavljevic DM. Scleroderma pattern of nailfold capillary changes as predictive value for the development of a connective tissue disease: a follow-up study of 3,029 patients with primary Raynaud’s phenomenon. Rheumatol Int. 2012;32(10):3039–45. [3]Jones GT, Herrick AL, Woodham SE, Baildam EM, Macfarlane GJ, Silman AJ. Occurrence of Raynaud’s phenomenon in children ages 12-15 years: Prevalence and association with other common symptoms. Arthritis Rheum. 2003;48(12):3518–21. [4]Pavlov-Dolijanović S, Damjanov N, Ostojić P, Sušić G, Stojanović R, Gacić D, et al. The prognostic value of nailfold capillary changes for the development of connective tissue disease in children and adolescents with primary Raynaud phenomenon: A follow-up study of 250 patients. Pediatr Dermatol. 2006;23(5):437–42. Disclosure of Interests: None declared