Distinct phenotypes of multisystem inflammatory syndrome in children: a cohort study

Table 2 Upper panel: MIS-C features differed between the respective COVID-19 waves. Lower panel: Distinct MIS-C features in patients presenting during the first phase of the COVID-19 pandemic (first and second wave combined) compared to those presenting during the second phase (third and fourth wave combined)

MIS-C features	Wave 1 vs. 2	Wave 1 vs. 3	Wave 1 vs. 4	Wave 2 vs. 3	Wave 2 vs. 4	Wave 3 vs. 4
Shock/hypotension	0.03	0.13	0.28	0.56	0.43	> 0.99
Skin rash	> 0.99	0.28	0.08	0.14	0.008	0.36
Peak ferritin	0.83	0.04	0.01	0.02	0.02	0.55
Liver enzyme abnormalities	0.67	0.39	0.32	0.06	0.05	> 0.99
Peak D-dimer	0.63	0.08	0.07	0.05	0.02	0.55
Peak troponin	0.002	0.02	0.002	0.66	0.2	0.14
Thrombocytopenia	0.37	0.07	0.01	0.21	0.04	0.36
Platelet count nadir	0.41	0.03	0.003	0.15	0.003	0.01
Albumin nadir	0.14	0.22	0.99	0.004	0.08	0.24
Treatment with corticosteroids	0.2	0.04	0.03	0.27	0.15	> 0.99
Treatment with biologicals	0.04	> 0.99	> 0.99	0.02	0.05	> 0.99
	Phase 1 (n = 32)	Phase 2 (n = 25)	P
Peak ferritin, mg/l (median, IQR)	370 (249–629)	1134 (409–1806)	0.001 (U = 195.5)
Liver enzyme abnormalities (n, %)	11 (34)	17 (68)	0.02
Peak D-dimer, mg/l (median, IQR)	2.01 (1.27–3.34)	4.81 (2.24–5.37)	0.004 (U = 155.0)
Peak NT-proBNP, ng/l (median, IQR)	3213 (1216–8483)	12,217 (3013–27,161)	0.02 (U = 121.0)
Hypoalbuminemia (n, %)	25 (81)*	24 (100)*	0.03
Albumin nadir, g/l (median, IQR)	24 (20–25)	19 (18–22)	0.005 (U = 208.5)
Thrombocytopenia (n, %)	11 (34)	18 (72)	0.007
Platelet counts nadir, x10E9/l (median, IQR)	215 (133–316)	127 (104–155)	0.003 (U = 218.5)
Treatment with corticosteroids (n, %)	21 (66)	23 (92)	0.03
Non-invasive/mechanical ventilation (n, %)	0	4 (16)	0.03

Upper panel: Numbers in the table represent P values. We refer to Table 1 for absolute numbers, percentages, median values and interquartile ranges of the MIS-C features across the different waves. Lower panel: Mann-Whitney U values are indicated between brackets. No differences were detected regarding the other MIS-C features (data not shown). (*one missing value; NT-proBNP = N-terminal B-type natriuretic peptide, n = number, IQR = interquartile range)

ISSN: 1546-0096