Fatal Neutropenic Enterocolitis in a Young Female After the First Round of Eculizumab for Paroxysmal Nocturnal Hemoglobinuria.

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare disorder characterized by glycosylphosphatidylinositol (GPI)-linked membrane protein deficiency, leading to hemolytic anemia and thrombosis. A subset of patients develop severe neutropenia, predisposing them to neutropenic enterocolitis (NEC). We present a case of fatal NEC following eculizumab therapy in a 31-year-old female with PNH. She presented with abdominal pain, fever, and neutropenia post-eculizumab. Despite aggressive management, including antibiotics and supportive care, she developed septic shock complicated by bacteremia, multiorgan failure, and two episodes of cardiac arrest, leading to severe lactic acidosis and ultimately progressing to brain death. The etiology of NEC in PNH patients remains multifactorial, involving immunocompromised and treatment-related factors. This case underscores the challenges in managing NEC and highlights the importance of early recognition and intervention in high-risk patients.