Evaluation of Macrophage Activation Syndrome in Patients with Systemic Juvenile Idiopathic Arthritis: A Single Center Experience

Table 2

SJIA patients classified with MAS according to the HLH-2004 diagnostic guidelines, MAS 2016 classification criteria, MS score, and/or ferritin/ESR ratio.

	Recurrent MAS	HLH-2004	MAS 2016^a	MS score^b	Ferritin:ESR ratio cut-off point ≥21.5^c
Patient 1		Not fulfilled	Fulfilled (3)	-1.1	53.7
Patient 10		Not fulfilled	Fulfilled (2)	0.3	164.2
Patient 15^d		Not fulfilled	Fulfilled (2)	-1.9	304.8
Patient 18	x	Fulfilled	Fulfilled (2)	-0.8	45.6
Patient 20		Not fulfilled	Not fulfilled	-0.7	13.8
Patient 22		Not fulfilled	Fulfilled (2)	-2.3	90.0
Patient 24	x	Fulfilled	Fulfilled (4)	3.3	481.1
Patient 30	x	Fulfilled	Fulfilled (3)	-0.19	164.3
Patient 32		Not fulfilled	Fulfilled (2)	-4.4	25.0
Fulfilled criteria		3/32	8/32	7/19	13/26
Sensitivity (%)^e		37.5 (8.5-75.5)		75 (34.9-96.8)	100 (63.1-100)
Specificity (%)^e		100 (85.8-100)		90.9 (58.7-99.7)	72.2 (46.5-90.3)
PPV (%)^e		100		85.7 (47-97.6)	61.5 (43.2-77.1)
NPV (%)^e		82.8 (73.7-89.1)		83.3 (59.7-94.4)	100

^aThe number in the parenthesis shows the number of fulfilled MAS criteria other than  μg/L. It was not possible to evaluate the 2016 MAS criteria in six patients due to missing data on ferritin. ^bCalculation of the MS score: . Patients with a MS are typed in italics. MS score could not be calculated for thirteen SJIA patients due to missing data on ferritin and/or fibrinogen. ^cPatients with a ferritin: ESR ratio cut are typed in italics. Ferritin to erytrocyte sedimentation rate ratio could not be calculated for 6 patients due to missing data on both ferritin and ESR. ^dPatient diagnosed in 2015 developed subclinical MAS 42 days after onset of sJIA. ^eSensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) calculated against 2016 MAS classification criteria and expressed as percentage with 95% confidence interval in parenthesis.