RESUMEN
We report a preterm (35 4/7 weeks) male neonate with Down's syndrome (DS) diagnosed with isolated pericardial effusion (PE) at 20 weeks of gestation. He was born by precipitous delivery, needed no resuscitation and presented within first 24 hours of life with respiratory distress, anemia due to feto-maternal bleed, hypotension, hepatomegaly, and coagulopathy. Postnatal echocardiography confirmed a 5 mm rim of PE without tamponade, normal cardiac structure, and function. He was stabilized with ventilation, packed red cell, fresh frozen plasma, inotropes (dopamine, dobutamine, and adrenaline), and steroid (hydrocortisone). Subsequent evaluation confirmed hypothyroidism, transient myeloproliferative disorder (TMD), hepatic failure due to fibrosis/cirrhosis with portal hypertension, and steroid sensitive hypotension on two occasions possibly due to adrenal insufficiency. PE completely resolved over 2 weeks. In view of progressively worsening liver failure with ascites and portal hypertension, the family opted for palliation. Literature review has been discussed regarding perinatal onset of PE in DS.