A total of 91 patients with MIS-C were included in this study. Sixty-one (67.0%) patients were male and 30 (33.0%) were female. The median age of patients was 6 years 6 months (range 5 months to 17 years). Of patients, 45 (49.5%) were ≤6 years of age and 22 (24.1%) were ≥12 years of age. Among 91 patients, 84 (92.3%) were previously healthy, while 7 (77 %) had underlying disease including asthma in 3 patients and one each with prematurity, cerebral palsy, Bardet-Biedel syndrome, and osteopetrosis.
Among 91 patients with MIS-C, 4 (4.4%) had positive real-time PCR results for SARS-CoV-2. The history of contact with a COVID-19 case was detected in 42.9% of MIS-C cases (n=39). Seventy (76.9%) patients had positive for COVID-19 immunoglobulin G and seven patients (7.7%) had positive for COVID-19 immunoglobulin M.
The rate of fever, hypotension, tachycardia, and other symptoms of the patients with MIS-C:
The fever was present in all the patients, and the median duration of fever before admission to the hospital was 5 days (minimum 1 to 12 days). Among the patients, 20.9% (n=19) had hypotension and 22.0% (n=20) of the patients had tachycardia. Eight patients (8.8%) had difficulty at breathing. The symptoms of the patients were summarized in table-1.
Among 91 patients, systolic dysfunction [ejection fraction (EF) below <50%] was present in 10 (11.0%) patients and coronary artery involvement was present in 5 (5.5%) patients. One patient experienced pericardial effusion (1.0%). The mitral valve regurgitation was present in 33 (36.2%) of the patients (table-1).
Treatment modalities of the MIS-C:
Of 91 patients, 22 (24.2%) were followed up in the pediatric intensive care unit (PICU) and 69 patients (75.8%) were followed up in the pediatric infectious diseases ward (table-2). The median duration of fever after hospitalization was 1 day (range 1 to 7 days). The median duration of hospitalization in the hospital was 9 days (2 days to 55 days) and the median duration of PICU stay of 23 patients was 5 days (range 2 to 50 days).
The initial treatment was intravenous immunoglobulin alone at 42 patients (46.2%)and intravenous immunoglobulin plus steroid with a dosage of 2 gr/kg was administered at 49 patients (53.8%).
Low molecular weight heparin was initiated in 65.9% of the patients (n=60). Acetylsalicylic acid was given to 53 (71.9%) patients with low dosage after discharge (after ceasing low molecular weight heparin). Eighteen patients (19.8%) required inotropic agents and 14 patients (15.4%) required respiratory support including high-flow nasal cannula. During follow-up, no mortality was observed in our study cohort.
What effect the decision for an initial steroid to IVIG at MIS-C duration of fever and time to start IVIG:
The median age of the patients in the group II was significantly higher compared to the patients in group I (96 months, 5 to 168 months vs 51 months,16 to 204;p<0.001). The ratio of severe MIS-C patients in the group II was 36.7% (n=18) and significantly higher compared to the rate of severe MIS-C patients in the group I (n=4, 9.5%) (p=0.01). The rate of moderate and mild MIS-C in the group II was 16.3% (n=8) and 46.9% (n=23), consecutively. The rate of moderate and mild MIS-C in the group I was 66.7% (n=28) and 23.8% (n=10). The rate of admission to PICU was 34.7% in the group II and 14.3% in the group I and the difference was significantly higher in the group II (p=0.026). The rate of hypotension was significantly higher in the group II (30.6%, n=15) compared to the group I (9.5%, n=4) (p=0.014). There was no significant difference was present regarding EF between two groups (p>0.05).
The platelet count and lymphocyte count were significantly lower in the group II compared to the group I (p=0.005 and p=0.0119) (table-2). The mean serum levels of C-reactive protein (CRP) values were significantly higher in the group II, while there was no significant difference at other laboratory variables present in two groups (p>0.05).
The prognosis and the treatment of choice:
The re-occurrence of fever was 26.5% (n=13) in the group II and 33.3% (n=14) in the group I and no significant difference was present (p<0.05). The rate of respiratory support was 14.3% (n=7) in the group II and 9.5% (n=4) in the group I, and there was no significant difference between the groups (p>0.05). The mean hospitalization duration was 9.9 ±1.2 days (2 to 55 days in the group I and 10.4 ±0.6 days (4 to 20 days) in the group II and no significant difference was present between these two groups (p>0.05)