Acute neurologic clinical manifestations and outcomes in children with thrombotic microangiopathies in paediatric intensive care units.

Neurological involvement is rare in paediatric thrombotic microangiopathies (TMAs), with scarce information to guide clinical management. Therefore, this study aimed to describe and compare the characteristics, risk factors, and outcomes between children with and without severe neurological involvement in the context of TMA requiring intensive care. This was a prospective multicentre observational study in 20 paediatric intensive care units (PICUs) in Spain, the MATUCIP Registry, from January 2017 to December 2025 including children aged more than 1 month with TMAs, who were followed up through discharge from the PICU. We collected routine care data and management was performed according to local practice. The main outcome was the incidence of severe neurological involvement, and secondary ones were its relation with supportive care, length of PICU stay, and laboratory findings. We included 160 patients (50.6% female) with a median age of 2.8 years (interquartile range [IQR], 1.6-6). At baseline, 121/160 presented with gastrointestinal (75.6%), 22/160 respiratory (13.8%), manifestations. Only 3 out of 160 (1.9%) patients presented initially with neurological manifestations, but up to 46 developed them during follow-up (28.7%). Most neurological cases were severe (31 out of 46, 67%), including altered level of consciousness (n = 22, 70.9%) and seizures (n = 14, 45.2%). Patients with neurological involvement required renal replacement therapy more frequently, eculizumab/ravulizumab administration, and had longer PICU length of stay.

conclusionsIn our cohort, almost one-third of participants developed neurological manifestations, most of them severe, during a PICU admission for TMA, and this was associated with prolonged recovery times and an increased need for supportive interventions. This warrants close neurological surveillance by PICU staff for the timely introduction of protective measures, although the impact of such measures on mortality and long-term outcomes needs further research. WHAT IS KNOWN: • TMA is a group of multisystemic diseases, and even though neurological involvement is not the most common manifestation, it has been associated with higher mortality and morbidity, making early detection and treatment crucial. WHAT IS NEW: • In our registry, neurological impairment occurred in one-third of TMA cases, and it was associated with poorer outcomes and a longer PICU stay. • Although the treatment is mainly supportive care, the onset of neurological manifestations may determine the indication for complement-inhibitor drugs.