The clinical outcome after inferior vena cava thrombosis in early infancy is unknown. We report the clinical long-term follow-up of 12 patients presenting inferior vena cava thrombosis within their first months of life (gestational age: 24-41 weeks; follow-up: 7+/-3 years). Accompanying renal venous thrombosis occurred in 9, and adrenal bleeding in 4 patients. A central venous catheter was related to the thrombosis in only four patients. Heterozygous factor V Leiden mutation was found in two of the eight infants without central venous catheter. Thrombolysis was performed in seven and effective in three infants; one infant required surgical thrombectomy. In three of eight infants with ineffective or with no therapy, spontaneous recanalization occurred during follow-up. No patient died of the thrombosis. Although no long-term anticoagulatory prophylaxis was performed, none of the children with persisting occlusion (n = 5) or stenosis (n = 1) of the inferior vena cava developed symptomatic thrombo-embolic complications. However, extensive internal collaterals (n = 6), visible varicosis (n = 5), pain in the legs (n = 3) and persisting renal disease (n = 3) with arterial hypertension (n = 2) were observed during follow-up.
Conclusion: Inferior vena cava thrombosis of early infancy frequently persists and may cause considerable long-term morbidity. New strategies for early and long-term therapy are necessary.