This is a one-month-old male, of Moroccan origin, who came to the emergency department with vomiting, refusal of food and abdominal distension of 4 days' duration. The pregnancy was controlled, with no obstetric or perinatal history of interest, and the baby was born at term with a weight appropriate for his gestational age. Examination revealed a fair general condition, with cutaneous and mucosal pallor and generalised oedema, predominantly in the lower extremities. A polyfocal grade IV/VI systolic murmur was auscultated. The abdomen was distended, with presence of superficial venous network and ascites. Laboratory examination showed normocytic normochromic anaemia, leukocytosis with normal formula, creatinine less than 0.2mg/dl and urea 10mg/dl, increased cholesterol and triglycerides, and decreased total protein and albumin, in addition to hyponatraemia, hypokalaemia and hypocalcaemia. Parathyroid hormone was slightly elevated. Urine proteinuria was in the nephrotic range with a proteinuria/creatinuria ratio of 33.7.

Given the suspicion of CNS, intensive diuretic and antiproteinuric therapy, antithrombotic prophylaxis, adjuvant treatment with alpha-calcidiol, iron, calcium carbonate and levothyroxine, as well as enteral nutrition with hyperproteic and hypercaloric formula were started. He required treatment with serum albumin and erythropoietin. The cardiological study diagnosed moderate valvular pulmonary stenosis and atrial septal defect. The genetic study found Frameshift type mutations for the NPHS1 gene, Intronic Variant type for the NPHS2 gene and Missense type for the WT1 gene.
At three months of age he was readmitted for seizures secondary to severe hypocalcaemia. Due to the high levels of intravenous calcium required for its control through a peripheral venous access, a third-degree burn occurred, which required the placement of a skin graft.
He required intensive care on two occasions at 4 and 6 months of age due to sepsis secondary to Staphylococcus hominis and Enterococcus faecalis, respectively, which were resolved with empirical antibiotherapy and subsequently according to antibiogram.
Finally, the patient died at 8 months of age due to bilateral pneumonia associated with pneumothorax with decompensation of his underlying pathology that caused refractory hypoxaemia.