Spontaneous abdominal aortic thrombosis, a rare cause of acute kidney injury in a newborn

Introduction : Neonatal aortic thrombosis is a rare but serious condition with potentially severe outcomes. Approximately 80% of cases are linked to umbilical catheterization, while not non-catheter-related cases are classified as spontaneous. Clinical presentation varies with the location and severity of thrombosis, ranging from asymptomatic cases to life-threatening emergency such as cardiac or respiratory failure, necrotizing enterocolitis, limb gangrene, or acute kidney injury (AKI) renal artery involvement. Materials and methods : This report describes a case of spontaneous abdominal aortic thrombosis in a newborn girl, resulting in AKI necessitating renal replacement therapy. Results : A full-term newborn breastfed girl experiences clinical deterioration on day 11, presenting with lethargy, feeding refusal, macrohematuria, anuria on day 12. Ultrasound Doppler revealed bilateral renal artery thrombosis, with laboratory findings of hyperazotemia, hypernatremia, hemoconcentration, and 18% weight loss. Despite fluid replacement, electrolyte correction, anuria persisted, requiring peritoneal dialysis. CT angiography confirmed abdominal aortic thrombosis extending from the superior mesenteric artery to the common femoral arteries. Treatment included unfractionated heparin and tissue plasminogen activator (Alteplase), but kidney function did not recover, leaving the child dialysis-dependent. Conclusions : This case highlights the rare occurrence of abdominal aortic thrombosis in the neonatal period, leading to AKI and chronic kidney disease (CKD) 5D due to cortical necrosis. Neonates are particularly vulnerable to thrombotic complications due to factors such a dehydration, hypernatremia, and polycythemia.