Peri-catheter calcification is an unusual and previously unreported complication of central venous (CV) catheterization in infants. A 1. 9 Fr Silastic CV catheter was placed in a term infant for administration of total parenteral nutrition and antibiotics following intra-abdominal sepsis. The catheter was removed, without complication, at a later date after another septic episode. Imaging studies performed in the investigation of a possible intra-abdominal abscess revealed a cylindrical density within a clot in the inferior vena cava (IVC). The density was presumed to be a retained catheter fragment. Further investigation indicated total occlusion of the IVC. Surgical exploration of the IVC revealed only a calcified thrombus. This case represents a rare and previously unreported complication of CV catheterization in infants. Diagnosing this condition on radiographic evidence alone can be difficult. It is hoped that awareness of the potential for this complication will avoid unnecessary invasive procedures in the future. We also suggest a high level of clinical suspicion and routine Doppler ultrasound investigations to detect IVC thrombosis when indwelling CV catheters are used in infants.