Acute metabolic and neurological crises: mortality rate and recurrences
| Crisis number | Patients at risk | Absence of crisis | Occurrence of crisis | Median age (months) | Deaths/survival | Mortality (%) |
| First | 50* | 5 | 45 | 14.2 | 22/23 | 49 |
| Second | 21† | 2 | 19 | 15.0 | 13/6 | 68 |
| Third | 6 | 1 | 5 | 32.1 | 3/2 | 60 |
| ≥Fourth | 2 | 1 | 4‡ | – | 0/1 | 0 |
| Overall | 50 | 10§ | 73 | 16.9 | 38/35 | 52 |
↵* Information concerning circumstances of death was not available for six patients who died several decades ago.
↵† Two of the 23 survivors of a first crisis died in undocumented circumstances. They are excluded from the following rows of the table.
↵‡ One surviving patient (the genetic compound of A354V and C1277Xdel8) experienced seven crises.
↵§ Patients with no further crises all survived. The 10 survivors include the 9 shown in the above column plus the one patient who survived >4 crises.