Table 2:
Frequency of Neurologic Complications
| Complication | Frequencya | Age, years | Days between influenza onset and IANC onset |
Presence of pre-existing neurologic disorderc |
Not back to neurologic baseline at dischargec |
|---|---|---|---|---|---|
| Any neurologic complicationb | 131 (100) | 4.7 (1.9, 9.3) | 1 (0, 3) | 74 (56) | 15 (11) |
| Seizures | 97 (74) | 4.3 (1.7, 8.2) | 1 (0,2) | 58 (60) | 9 (7) |
| Febrile seizures | 29 (22) | 1.6 (1.2, 2.4) | 1 (0,2) | 1 (3) | 1 (33) |
| Status epilepticus | 50 (38) | 3.3 (1.6, 6.4) | 0.5 (0, 2) | 32 (64) | 4 (8) |
| Encephalopathy | 44 (34) | 7.0 (3.1, 11.3) | 2 (0, 4) | 27 (61) | 8 (18) |
| Any neurologic complication other than seizure or encephalopathy | 20 (15) | 7.3 (3.7, 12.4) | 2.5 (1, 4) | 9 (45) | 8 (40) |
| Meningitis/encephalitis | 8 (6) | 11.6 (4.6, 15.2) | 0.5 (0, 2.5) | 5 (63)d | 4 (50) |
| Ataxia | 8 (6) | 7.7 (2.4, 11.9) | 2.5 (1, 3) | 4 (50) | 2 (25) |
| Cerebral edema | 3 (2) | 6.4 (2.8, 14) | 1 (0, 2) | 2 (67) | 3 (100) |
| Arterial ischemic stroke | 1 (1) | 5.7 | 7 | 0 | 0 |
| Chronic inflammatory demyelinating polyneuropathy (CIDP) flare | 1 (1) | 12.1 | 11 | 1 | 1 |
| Clonus | 1 (1) | 4.7 | 11 | 0 | 0 |
| Demyelinating disorder | 1 (1) | 6.9 | 16 | 0 | 1 |
| Motor deficit | 1 (1) | 2.8 | 2 | 0 | 1 |
| Mutism | 1 (1) | 2.8 | 2 | 0 | 1 |
| Posterior reversible encephalopathy syndrome (PRES) | 1 (1) | 7.4 | 5 | 0 | 1 |
a
Some hospitalizations had ≥1 neurologic complication, so percentages do not add up to 100%
b
Categorical variables are described using n (%). Continuous variables are described using median (interquartile range)
c
Percentages calculated with total number of each neurologic complication as denominator; some children had more than one neurologic complication.
d
None of the children with a pre-existing neurologic disorder had a cerebrospinal fluid diversion device (e.g. ventriculoperitoneal shunt) or any identified co-infections.