TABLE 1.
Demographic and Clinical Characteristics of 90 Children with Long COVID, and the Main Features of the Medical Evaluation
| General Characteristics | N (%) |
|---|---|
| Age, mean ± SD, yrs | 12 ± 5 |
| Gender, male:female | 1.4:1 |
| BMI percentile by WHO growth charts > 85 | 23 (25.6) |
| Very early preterm birth <32 wks gestation | 2 (2.2) |
| Early preterm birth 32–36 wks gestation | 3 (3.3) |
| Background medical conditions | |
| Immunodeficiency* | 5 (5.6) |
| Autoimmune or inflammatory disease† | 4 (4.5) |
| Asthma | 2 (2.2) |
| Anxiety or depressive disorder | 3 (3.3) |
| Attention deficit hyperactivity disorder | 12 (13.3) |
| Other‡ | 33.3 |
| Participation in competitive sports | 12 (13.3) |
| Severity of the acute COVID-19 illness§: asymptomatic | 3 (3.3) |
| Mild | 82 (91.1) |
| Moderate | 6 (6.7) |
| Severe | 2 (2.2) |
| Hospitalization during the acute illness | 11 (12.2) |
| Positive COVID-19 qRT-PCR during the acute illness, n = 89 | 89 (100) |
| COVID-19 serology during evaluation,¶ n = 72, positive | 58 (80.6) |
| Borderline | 5 (5.6) |
| PIMS before evaluation | 1 (1.1) |
| Medical evaluation | |
| Positive findings on physical examination | 5 (5.6)‖ |
| Laboratory investigation** | |
| Sedimentation rate > 20 mm/h or C-reactive protein > 0.5 mg/dL | 4 (4.9) |
| Troponin≥ 14 ng/L | 1 (1.3) |
| Creatine phosphokinase ≥ 200 units/L | 11 (14.1) |
| Ferritin ≤ 20 µg/L | 29 (43.9) |
| Hemoglobin ≤ 11 g/dL | 3 (3.6) |
| Pulmonary evaluation | |
| Chest radiograph changes | 12 (133)†† |
| Pulmonary function tests | |
| Abnormal spirometry, FEV1 < 80% or FEV1/FVC < 0.8, n = 60 | 5 (8.3) |
| Abnormal exercise challenge test,‡‡ ΔFEV1 ≥ 12%, n = 51 | 3 (5.9) |
| Positive bronchodilator response, ΔFEV1 ≥ 12%, n = 29 | 15 (51.7) |
| Air trapping by plethysmography, RV/TLC > 125%, n = 55 | 15 (27.3) |
| Diffusion capacity < 70%, n = 50 | 1 (2.0)§§ |
| Cardiac evaluation | |
| Abnormal findings on electrocardiograph | 2 (2.2)¶¶ |
| Abnormal findings on echocardiography, n = 63 | 0 (0) |
| Abnormal holter, n = 4 | 0 (0) |
| Abnormal cardiac MRI, n = 3 | 1 (33.3) |
| Maximal pulse during exercise stress test <180 b/min,6 n = 51 | 34 (66.7) |
BMI, body mass index; FEV1, forced expiratory volume in the first second; FEV1/FVC, ratio of FEV1 to forced vital capacity; PIMS, pediatric inflammatory multisystem syndrome; qRT-PCR, quantitative reverse transcription polymerase chain reaction; RV/TLC, ratio of residual volume to total lung capacity; WHO, World Health Organization.
*Including, kidney transplantation due to microscopic polyangiitis (1), kidney transplantation due to Schimke immuno-osseous dysplasia (1), glioma with chemotherapy (1), s/p bone marrow transplantation due to myelodysplastic syndrome (1), asplenia due to spherocytosis (1).
†Including, Crohn’s disease (1), Familial Mediterranean Fever (1), type 1 diabetes (1), celiac disease (1).
‡Including, dysplastic kidney (1), bilateral cochlear implant (1), convulsive disorder (1).
§By the National Institute of Health symptom severity criteria.4
¶In 4 adolescents, serology was taken after 1 dose of BNT162b2 (Pfizer-BioNTech COVID-19 vaccine).
‖Including, decreased muscle strength, dyspnea or tremor.
**Serum was depleted in 17 children; One patient refused blood tests.
††Including infiltrates (7), peribronchial thickening (3) and interstitial pattern (1).
‡‡The exercise test was terminated prematurely in four patients due to dyspnea or myalgia.
§§S/p severe acute COVID-19.
¶¶Inverted T waves and ST segment elevation.