Discussion
Inferior vena cava thrombosis (IVCT) in a congenitally normal patient is
rare and is usually a result of a predisposing hypercoagulable state
along with an acquired pathology in the IVC or one of its adjacent
structures.8-11 Etiologically, there are prothrombotic
factors such as thrombophilia, malignancy, oral contraceptives, smoking,
obesity, pregnancy, hormonal replacement therapy, and nephrotic
syndrome. Besides these, there are abdominal pathologies such as renal
cell tumor, abdominal masses producing extrinsic compression such as a
very large uterine fibroid, Budd-Chiari syndrome, abdominal
trauma/surgery, May-Thurner syndrome, and thrombotic occlusion of an IVC
filter. Meanwhile, a recent study has shown local problems such as IVC
anomalies contribute 11.3 percent, external venous compression
contributes 11.3 percent, malignancy contributes 17.0 percent, and the
presence of lupus anticoagulants contributes 10.9 percent to the risk of
IVCT.12 There are some interesting clinical aspects in
our case report. He was a congenitally normal IVCT patient who didn’t
relate to the aforementioned etiologies and differed from them in all
aspects. He had a sudden onset of symptoms related to venous
thromboembolism. The only medical history he had was of hypertension,
which was well managed by anti-hypertensive medication. We observed a
high level of serum homocysteine, which was a new observation for us.
The association between deep vein thrombosis and hyperhomocystinemia was
first reported in 1991, and since then a large number of prospective and
retrospective trials have established a relation between
hyperhomocysteinemia and deep vein thrombosis.13 Mild
hyperhomocysteinemia appears to be an independent risk factor for
arterial vascular disease and thromboembolic risk
factors.14 Homocysteine levels can be raised by
altered methionine metabolism, which can occur as a result of genetic
defects affecting transcription of enzymes responsible for homocysteine
metabolism. Many other factors, such as age, smoking, renal impairment,
diabetes mellitus, hypothyroidism, and other nutritional deficiencies of
folic acid, vitamin B6, and vitamin B12, and drugs such as phenytoin,
carbamazepine, and methotrexate, may be linked to
hyperhomocystinemia.13,15Interestingly, we describe a
rare case of IVCT with no identifiable risk factors contributing to IVCT
except hyperhomocysteinemia, which captures the attention.