Extracorporeal kidney support in neonates and infants: therapeutic perspectives and outcomes in multiple organ dysfunction syndrome—a structured narrative review

Background Multiple organ dysfunction syndrome (MODS) remains a major challenge in the intensive care of neonates and infants and is associated with substantial morbidity and mortality, particularly in the presence of sepsis and acute kidney injury. Conventional kidney replacement and detoxification strategies may be difficult to implement in neonates and low-weight infants because of technical and physiological limitations. Hemodiafiltration (HDF), which combines convective and diffusive clearance mechanisms, has emerged as a potential extracorporeal support modality for metabolic and inflammatory control while maintaining hemodynamic stability. Objective To provide a structured narrative review of the available literature on the clinical applications, potential benefits, safety considerations, and technical aspects of hemodiafiltration in neonates and infants with multiple organ dysfunction syndrome. Methods This study was conducted as a structured narrative review with systematic search elements. PubMed, Scopus, Web of Science, and the Cochrane Library were searched for publications from January 2018 to October 2025. Earlier landmark publications identified through reference-list screening were additionally included to provide historical and technical context. A structured search and descriptive selection process was used to identify publications relevant to extracorporeal blood purification in neonates and infants. Eligible populations included neonates (<28 days of life) and infants beyond the neonatal period (28 days to <12 months) weighing ≤8 kg with MODS, sepsis, hyperammonemia, or acute kidney injury. Observational studies, case series, registry reports, and review articles addressing HDF or continuous kidney replacement therapy (CKRT) were considered. Studies involving broader pediatric populations were included only when relevant data for eligible neonatal or infant subgroups were separately available. Publications lacking clinically relevant information were excluded from the descriptive synthesis. Owing to substantial heterogeneity in study designs, patient populations, and reported outcomes, findings were synthesized descriptively. Results The reviewed literature suggests that HDF may be associated with metabolic stabilization, correction of acid–base disturbances, and improvement in electrolyte balance in selected neonates and infants. Limited case-based evidence has also described hemodynamic stabilization and reduced vasopressor support following extracorporeal therapy; however, these observations remain insufficient to establish a causal treatment effect. Clinical outcomes varied substantially across studies because of differences in patient characteristics, clinical indications, and treatment protocols. Reported complications included hypotension, circuit clotting, and coagulation abnormalities, although their frequency and clinical significance differed considerably among publications. Conclusions Current evidence suggests that hemodiafiltration may represent a promising extracorporeal support strategy for selected neonates and infants with MODS, particularly for metabolic stabilization and organ support. However, the available evidence remains limited, heterogeneous, and predominantly based on observational studies and case series. Further multicenter prospective studies are required to clarify optimal indications, treatment protocols, and long-term outcomes.