Plasma exchange therapy for acute necrotizing encephalopathy of childhood

IMPORTANCE: Acute necrotizing encephalopathy (ANE) is a rare disease with high mortality. Plasma exchange (PLEX) has recently been reported to treat ANE of childhood (ANEC), but its efficacy is uncertain. OBJECTIVE: This study aimed to investigate the effectiveness of PLEX on ANEC. METHODS: A retrospective study was conducted in four pediatric intensive care units from December 2014 to December 2020. All patients who were diagnosed with ANEC were included; however, these patients were excluded if their length of stay was less than 24 h. Participants were classified into PLEX and non‐PLEX groups. RESULTS: Twenty‐nine patients with ANEC were identified, 10 in the PLEX group and 19 in the non‐PLEX group. In the PLEX group, C‐reactive protein, procalcitonin, alanine aminotransferase, and aspartate aminotransaminase levels were significantly lower after 3 days of treatment than before treatment (13.1 vs. 8.0, P = 0.043; 9.8 vs. 1.5, P = 0.028; 133.4 vs. 31.9, P = 0.028; 282.4 vs. 50.5, P = 0.046, respectively). Nine patients (31.0%, 9/29) died at discharge, and a significantly difference was found between the PLEX group and non‐PLEX group [0 vs. 47.4% (9/19), P = 0.011]. The median follow‐up period was 27 months, and three patients were lost to follow‐up. Thirteen patients (50.0%, 13/26) died at the last follow‐up, comprising three (33.3%, 3/9) in the PLEX group and ten (58.8%, 10/17) in the non‐PLEX group, but there was no significant difference between the two groups (P = 0.411). Three patients (10.3%, 3/29) fully recovered. INTERPRETATION: PLEX may reduce serum C‐reactive protein and procalcitonin levels and improve liver function in the short term. PLEX may improve the prognosis of ANEC, and further studies are needed.