ABSTRACT
To assess the microvascular abnormalities in patients with juvenile onset systemic lupus erythematosus [SLE] using the nailfold capillaroscopy [NFC] and to measure the levels of anti-annexin V antibody [a-AXV Ab] titer to correlate them with each other and with renal affection. This study was conducted on twenty patients with juvenile onset SLE and ten healthy controls. All the patients and controls were subjected to history taking and clinical examination, laboratory investigations especially kidney function tests, ANA and anti-ds-DNA and quantitative assay of a-AXV Ab titer. SLE disease activity index and NFC were also performed. The mean capillary number and length in the patients was 7.05 +/- 1.76 and 477.1 +/- 157.01 respectively, showing a significant difference from the controls [10 +/- 1.05 and 315 +/- 105.01 respectively], while there was no significant difference regarding capiliary width. Tortuous capillaries were found in 13 patients showing a significant difference from the controls having hairpin capillaries. Organized capillaries were found in 3 patients and all the controls. The mean a-AXV Ab titer in patients was 226.45 +/- 117.66 AU/ml showing a significant difference from the controls [5.6 +/- 1.71 AU/ml]. Proteinuria showed a positive significant correlation with a-AXV Ab titer, capillary width and length [r=0.530, 0.457 and 0.447 respectively] while it was negatively correlated with capillary number [r=-0.459]. Anti-AXV Ab titer was positively correlated with capillary length [r= 0.509]. At cut-off value 160 AU/ml, a-AXV Ab titer showed sensitivity [Sn] and specificity [Sp] 100% in discriminating lupus nephritis [LN] from negative LN while capillary length showed Sn and Sp 100 and 70% at cut-off 370 and capillary width had 70% Sn and 80% Sp at cut-off 20 NEC is of value in detecting micro vascular abnormalities in juvenile onset SLE and its analysis especially capillary length in combination with a-AXV Ab titer may be helpful in raising suspicion for lupus nephritis