Neonatal liver failure and haemophagocytic lymphohistiocytosis caused by a new perforin mutation

Acute liver failure is a rare heterogeneous syndrome in neonates. We report of a newborn with haemophagocytic lymphohistiocytosis presenting as acute liver failure. Pancytopenia and multi-organ failure occurred later in the course. He carried two mutations of the perforin gene (PRF-1), one of which not previously described, causing a complete loss of perforin expression and natural killer cell function. Conclusion:  Perforin expression and function should be promptly assessed in neonatal/infantile acute liver failure, as haemophagocytic lymphohistiocytosis requires specific treatment and represents a contra-indication to liver transplant.