Calcified thrombus in the inferior vena cava in infants and children.

Calcified thrombi in the prerenal (suprarenal) segment of the inferior vena have a characteristic radiographic appearance that permits accurate "plain film" diagnosis. Most have been fortuitously discovered in infants and young children. None of the affected individuals has had clinical evidence of venous obstruction. Vena caval obstruction is usually incomplete. Uncalcified clot caudal to the calcified thrombus caused complete obstruction of the inferior vena cava and renal veins in one of our patients, a healthy infant; since collateral flow was adequate surgery was not advised. We believe that aggressive diagnostic and therapeutic measures are unnecessary in the management of infants and children with calcified thrombi in the inferior vena cava.