Central nervous system involvement in hemolytic uremic syndrome (HUS)--a retrospective analysis of cerebral CT and MRI studies.

PURPOSE: To evaluate the morphological changes of cerebral involvement in children with HUS utilizing CT and MRI. METHOD AND PATIENTS: We retrospectively analyzed 13 cranial CTs (CCT) and 3 cranial MRI studies of 5 out of 93 patients with clinically proven HUS and severe CNS involvement (seizures and coma and dysregulation of breathing) referred to the department of pediatric nephrology (aged 1.5-15 years, median 2 years, 2 girls, 3 boys) between 1987-2000.
RESULTS: Three of 5 patients had CT and MRI studies, 2 patients had CT scans only. One of 2 patients with isolated basal ganglia ischemia and normal first CCT developed a secondary hemorrhagic infarction. Another patient with an initially normal MRI developed an infarction of the right cerebral arteries with mass effects. One of 2 patients with basal ganglia involvement showed additional infarction of thalami and external and internal capsules whereas the other had only minimal involvement of adjacent white matter, but consecutive hemorrhagic infarction. Four of 5 children died (3 of them with varying extents of basal ganglia and adjacent white matter involvement, 1 with right cerebral artery infarction). Basal ganglia involvement was found in the majority of cases as well as in all lethal cases. The surviving patient with isolated basal ganglia involvement now suffers from tetraspastic disorder and convulsions.
CONCLUSION: Cerebral involvement is one of the major complications of HUS. According to the literature, basal ganglia involvement in HUS is common and quite often associated with other cerebral pathologies. First imaging findings may not show pathologies. Contradictory to previous reports, even children with isolated basal ganglia pathology and/or less involvement of white matter and coma may either die from the underlying disease or their clinical outcome may be poor.