Characteristics of patients with paediatric inflammatory multisystem syndrome temporally associated with SARS-CoV-2 (PIMS-TS), cross-tabulated with the presence of acute kidney injury (AKI; stages 1–3) during hospital admission
| Variable | Non-AKI (n=77) | AKI stages 1–3 (n=33) | P value |
| Demographics | |||
| Median age, years (IQR) | 105 (8.1–13.5) | 9 (7.1–10.9) | 0.08 |
| Male (%) | 46 (60) | 17 (51) | 0.64 |
| Ethnicity | |||
| Black/African/Caribbean/black British (%) | 20 (26) | 19 (58) | 0.004 |
| Asian/Asian British (%) | 27 (35) | 6 (18) | |
| White (%) | 16 (21) | 3 (9) | |
| Mixed/multiple ethnic groups (%) | 9 (12) | 3 (9) | |
| Other (%) | 5 (6) | 2 (6) | |
| Median height, cm (IQR) | 144 (124–160) | 140 (128–158) | 0.55 |
| Median BMI centile (IQR) | 80.7 (46–96) | 91 (57–99) | 0.18 |
| Median number of days admitted | 7 (6–10) | 9 (8–11) | 0.45 |
| Comorbidities* | 5 (6) | 1 (3) | 0.47 |
| SARS-CoV-2 status | |||
| SARS CoV-2 PCR positive (%) | 21 (28) | 12 (36) | 0.34 |
| Serology positive (%) | 73 (95) | 32 (97) | 0.78 |
| Symptoms on admission | |||
| Fever (%) | 77 (100) | 33 (100) | 1 |
| Rhinitis (%) | 0 (0) | 1 (3) | 0.09 |
| Respiratory distress (%) | 18 (23) | 14 (42) | 0.04 |
| Cough (%) | 7 (9) | 2 (6) | 0.72 |
| Abdominal pain (%) | 58 (75) | 22 (66) | 0.35 |
| Diarrhoea (%) | 42 (55) | 23 (70) | 0.14 |
| Vomiting (%) | 45 (58) | 21 (64) | 0.61 |
| Admission blood parameters | |||
| Median triglyceride peak, mmol/L (IQR) | 2.9 (1.8–3.7) | 3.62 (2.6–4.6) | 0.04 |
| Median ferritin peak, μg/L (IQR) | 713 (422–1641) | 1192 (818–1872) | 0.03 |
| Median CRP peak, mg/L (IQR) | 262 (182–307) | 313 (278–352) | <0.001 |
| Median IL-6 peak, pg/L (IQR) | 120 (50–305) | 71 (50–439) | 0.4 |
| Median D-dimer peak, ng/mL (IQR) | 2468 (1351–4581) | 5259 (2168–12486) | 0.04 |
| Median NT-proBNP peak, pg/mL (IQR) | 11 777 (3183–23562) | 23 072 (7103–32955) | 0.03 |
| Median troponin, ng/L (IQR) | 105 (39–266) | 301 (116–570) | 0.09 |
| Median sodium nadir, mmol/L (IQR) | 133 (131–135) | 133 (131–135) | 0.88 |
| Median phosphate nadir, mmol/L (IQR) | 0.83 (0.66–0.96) | 0.85 (0.76–0.98) | 0.53 |
| Median lymphocyte nadir, 109/L (IQR) | 0.82 (0.52–1.21) | 0.8 (0.52–1.15) | 0.19 |
| Median albumin nadir, g/L (IQR) | 25 (23–29) | 24 (22–26) | 0.1 |
| Renal parameters | |||
| Median creatinine peak, μmol/L (IQR) | 57.5 (42–71) | 132 (96–216.7) | – |
| Median urea peak, mmol/L (IQR) | 5.7 (4.8–7.4) | 14.2 (9.5–19.7) | – |
| Median eGFR, mL/min/1.73 m2 (IQR) | 92 (77–118) | 41 (24–52) | – |
| Median urine albumin/creatinine ratio, mg/mmol (IQR) | 3 (1.62–4.4) | 6.6 (2.7–9.7) | 0.04 |
| Median urine RBP/creatinine ratio, μg/mmol (IQR) | 267 (77–1451) | 3000 (354–3003) | 0.17 |
| Median urine NAG/creatinine ratio, U/mmol (IQR) | 114 (47–370) | 239 (233–264) | 0.44 |
| Dipstick proteinuria (%) | 4 (5) | 4 (12) | 0.29 |
| Dipstick haematuria (%) | 14 (18) | 7 (21) | 0.81 |
| Kidney ultrasonography | |||
| Not performed (%) | 8 (10) | 4 (12) | 0.21 |
| Normal (%) | 49 (64) | 17 (52) | |
| Abnormal† (%) | 20 (26) | 12 (36) | |
| Intensive care | |||
| PICU admission (%) | 65 (84) | 33 (100) | 0.016 |
| Median duration of PICU stay, days (IQR) | 3 (2–5) | 4 (3–5) | 0.18 |
| Intubation (%) | 10 (13) | 12 (36) | 0.005 |
| Median duration of mechanical ventilation, days (IQR) | 2.5 (2–5.25) | 1.5 (1–3) | 0.14 |
| Inotropic support (%) | 52 (68) | 32 (97) | 0.001 |
| Median duration of inotropic support, days (IQR) | 1 (0–2) | 2 (1–3) | 0.04 |
| Echocardiography finding | |||
| No myocardial dysfunction (%) | 48 (62) | 15 (45) | 0.1 |
| Myocardial dysfunction (%) | 29 (38) | 18 (55) | |
| Medications | |||
| PIMS-TS therapeutic medications | |||
| Methylprednisolone (%) | 65 (84) | 26 (79) | 0.47 |
| IVIG (%) | 53 (69) | 24 (73) | 0.68 |
| Anakinra (%) | 5 (6) | 3 (9) | 0.63 |
| Tocilizumab (%) | 3 (4) | 2 (6) | 0.62 |
| Remdesivir (%) | 1 (1) | 0 (0) | 0.99 |
| Median number of nephrotoxic medications (IQR) | 0 (0–1) | 1 (0–1) | 0.37 |
| Nephrotoxic medications | |||
| Vancomycin (%) | 4 (5) | 0 (0) | 0.31 |
| Gentamicin (%) | 4 (5) | 2 (6) | 0.99 |
| Amikacin (%) | 15 (19) | 10 (30) | 0.22 |
| Aciclovir (%) | 7 (9) | 7 (21) | 0.12 |
| Trimethoprim/co-trimoxazole (%) | 2 (3) | 0 (0) | 0.99 |
| NSAIDs (%) | 19 (25) | 8 (24) | 0.96 |
Data are n (%) or median (IQR).
*Comorbidities were: type 1 diabetes mellitus (n=2), sickle cell disease (n=2) and ventriculoperitoneal shunt for obstructed hydrocephalus (n=2).
†Abnormal kidney ultrasonography consisted of: loss of corticomedullary differentiation and/or increased echogenicity, unilaterally or bilaterally enlarged kidneys (>95th centile), unilaterally small kidney (<5th centile), unilateral ectopic kidney, evidence of scarring, duplex collecting system and pelvicalyceal dilatation.
BMI, body mass index; CRP, C reactive protein; eGFR, estimated glomerular filtration rate; IL-6, interleukin 6; IVIG, intravenous immunoglobulin; NAG, N-acetyl-β-D-glucosaminidase; NSAIDs, non-steroidal anti-inflammatory drugs; NT-proBNP, N-terminal pro B-type natriuretic peptide; PICU, paediatric intensive care unit; RBP, retinol-binding protein.