Major Infections of Newly Diagnosed Childhood-Onset Systemic Lupus Erythematosus

Figures & data

Figure 1 (A) Sixty-three major infection events were recorded. Over ninety present (n=57, 90.5%) of the infection events happened within the first 6 months after the initial diagnosis of cSLE. (B) Ten patients had admitted to the intensive care unit (ICU) related to the infection event.

Table 1 Demographics and Characteristics of Patients with or without Major Infections Within the First 6 Months After the Diagnosis of the cSLE

	Patients with Major Infection Within 6 Months n=57	Patients without Major Infection (Controls) n=41	P
Age at diagnosis, (years)	11.23±1.99	10.93±1.90	0.454
Female, n(%)	51 (89.5%)	38 (92.7%)	0.587
SLEDAI scores	13.82±4.28	9.49±3.80	<0.001
Lupus Nephritis, n(%)	26 (45.6%)	7 (17.1%)	0.003
Neuropsychiatric Lupus, n(%)	15 (26.3%)	7 (17.1%)	0.279
Serositis, n(%)	15 (26.3%)	4 (9.8%)	0.041
Gastrointestinal involvement, n(%)	6 (10.5%)	3 (7.3%)	0.587
TMA and TTP, n(%)	5 (8.8%)	1 (2.4%)	0.197
Leucocyte count <3×109/L, n(%)	38 (66.7%)	22 (53.7%)	0.192
Lymphocyte count <0.8×109/L, n(%)	28 (49.1%)	2 (4.9%)	<0.001
Platelet count <100×109/L, n(%)	23 (40.4%)	18 (43.9%)	0.725
IgG <7g/L, n(%)	10 (17.5%)	6 (14.6%)	0.701
Treatment involved within 1 months before major infection events or enrolment
Use of hydroxychloroquine, n(%)	44 (77.2%)	38 (92.7%)	0.041
Methylprednisolone pulse therapy, n(%)	29 (50.9%)	13 (31.7%)	0.059
Maximum prednisone (mg/day)	414.47±401.18	277.81±367.76	0.088
Use of cyclophosphamide, n(%)	10 (17.5%)	3 (7.3%)	0.141
Use of mycophenolate mofetil, n(%)	8 (14.0%)	3 (7.3%)	0.299
Use of cyclosporine A, n(%)	4 (7.0%)	1 (2.4%)	0.310
Use of methotrexate, n(%)	0 (0.0%)	1 (2.4%)	0.236
Use of Rituximab, n(%)	1 (1.8%)	0 (0.0%)	0.394

Abbreviations: TMA, thrombotic microangiopathy; TTP, thrombotic thrombocytopenic purpura.

Table 2 Characteristics of Major Infection Events

Site	Number	Microbiology (n)
Definitive diagnosis
Pneumonia	2	Pneumocystis jirovecii (2)
Bacteremia* identified by blood cultures or next-generation sequencing	18	Staphylococcus (9), Streptococcus (3), Klebsiella pneumoniae (2), Enterococcus (2), Pseudomonas aeruginosa(2)
Serous cavity infections	6	Streptococcus (3), Mycoplasma(2), Klebsiella pneumoniae (1)
Central nervous system infections	2	Cryptococcus neoformans (2)
Urinary tract infections	2	Staphylococcus (2)
Clinical diagnosis
Pneumonia	33	/

Note: *Among the above 18 bacteremia events, 2 cases were mixed infected with Epstein-Barr virus at the same time.

Table 3 Multivariate Analysis of the Factors Associated with the Major Infection Events Within the First 6-Month After the Diagnosis of cSLE

	Unadjusted			Adjusted for Age and Gender
	OR	95% CI	P	OR	95% CI	P
SLEDAI >10	3.78	1.19 to 11.97	0.024	3.69	1.13 to 12.04	0.030
Nephritis	4.18	1.22 to 14.26	0.023	4.18	1.07 to 16.37	0.040
Serositis	1.70	0.37 to 7.87	0.500	1.78	0.38 to 8.47	0.468
Lymphocyte count <0.8×109/L	21.95	4.15 to 116.14	<0.001	21.90	4.08 to 117.33	<0.001
Methylprednisolone pulse therapy	1.98	0.63 to 6.18	0.240	1.91	0.60 to 6.02	0.272
Hydroxychloroquine	0.47	0.08 to 2.74	0.398	0.441	0.07 to 2.74	0.380

Figure 2 (A) The number and frequency of major infection events in the cSLE patients with different risk scores was presented. (B) Patients in the high risk group [score (number of predictors) ≥2] had higher rates of the major infection occurrence than those in the low risk group (score ≤ 1) during the 6 months after the diagnosis of the cSLE. (HR:14.10, 95% CI 8.43 to 23.59, P<0.001).

Table 4 Performance of the CALL Score Evaluated by Receiver Operating Characteristic (ROC) Curve Analysis

Model	AUC (95% CI)	Sensitivity	Specificity
Whole cohort (n=98)	0.89(0.81–0.97)	93.1%	84.6%
Subgroup of pneumonia (n=35)	0.79(0.57–0.99)	85.7%	71.4%

Abbreviation: AUC, area under receiver operating characteristic curve.