Table 1. Clinical phenotype of affected individuals. HLH = hemophagocytic lymphohistiocytosis; ISG = interferon-stimulated gene.
| Clinical Feature | Proband (II:3) | Sibling (II:4) |
|---|---|---|
| Premature birth | Yes | Yes |
| Neonatal thrombocytopenia | Yes | No |
| Apnea requiring respiratory support | Yes | Yes |
| Seizures | Yes | Abnormal EEG |
| Developmental delay | Yes | Yes |
| White matter changes | Yes | Yes |
| Intracranial calcification | Yes | Yes |
| Intracerebral hemorrhage | Yes | Yes |
| Cerebellar hypoplasia | No | Yes |
| Sterile fevers | Yes | No |
| HLH-like inflammation | Yes | No |
| Hyperferritinemia | Yes | Borderline |
| Hypertension | Yes | Borderline |
| Acute kidney injury | Yes | No |
| Proteinuria | Yes | Yes |
| Thrombotic microangiopathy | Yes | Possible |
| Elevated D-dimers | Yes | Yes |
| High ISG score | Yes | Yes |
| Age at death | 20 months | 3 months |