Vascular complications are a well-known complication of liver transplantation, especially in children, being most common in the portal vein and hepatic artery (1
). HVOO following liver transplantation is less common, with an incidence reported between 1% and 7% (3
). This often occurs in the early post-operative period (2
), possibly from direct compression of the vein, but can occur several months to years later (1
), from fibrotic changes at the anastomotic site (3
In one study, ascites was the most common clinical sign of HVOO following pediatric liver transplantation (4
). PLE is a very rare complication of Budd–Chiari syndrome (5
), even with inferior vena cava obstruction (6
). To our knowledge, there have only been two reported cases of PLE secondary to HVOO following liver transplantation, one in a 42-yr-old male (7
), and the other in a 14-yr-old female (8
); a case in an infant has not been previously reported.
PLE is caused by abnormalities of the lymphatic system resulting in leakage of protein-rich lymph or mucosal injury with increased permeability (9
). It has been hypothesized that in Budd–Chiari syndrome, portal hypertension resulting from the obstruction can lead to bowel mucosa edema, with increased permeability and leakage of albumin, which defines PLE (6
). Another theory is the development of acquired lymphangiectasia after liver transplantation (5
). In our patient, there was no histologic evidence of intestinal lymphangiectasia on small bowel biopsies and additionally she did not have lymphopenia and low immunoglobulin levels, which can be seen in intestinal lymphangiectasia. However, her presentation was consistent with portal hypertension with gross ascites and esophageal varices seen on endoscopy. One puzzling aspect was that despite evidence of portal hypertension our patient did not develop splenomegaly at any point. In addition, there was a clear temporal relationship between the post-venoplasty decrease in HV-RA pressure gradient and an improvement of diarrhea, serum albumin level, and ascites.
Duplex ultrasound is considered a useful, readily available tool to identify HVOO (10
), with findings such as sluggish flow, absence of flow, or reversed flow in outflow veins (4
). In our patient, the normal duplex ultrasound of hepatic vasculature and unusual clinical features led to a delay in diagnosis. The duplex ultrasound may have been technically difficult in our patient owing to her young age and agitation. A CT scan of her abdomen and echocardiogram also failed to identify HVOO. After venography, all previous imaging was re-reviewed to look for signs that may have helped detect the HVOO, but none could be identified. Finally, the liver biopsy with zone 3 sinusoidal congestion suggested the diagnosis which was only confirmed by venography.
Treatment of HVOO can be accomplished by open surgical revision, venoplasty, or endovascular stent. Venoplasty is frequently successful but often requires re-intervention (3
). Our patient underwent successful venoplasty of the hepatic vein–inferior vena cava anastomosis but has required several repeat procedures. Usually if repeated procedures are needed, an endovascular stent may prove to be beneficial (3
). However, in our patient a stent may not be possible owing to the very close proximity of the hepatic vein, inferior vena cava, and right atrium, because of the patient’s small size and location of the anastomosis; therefore, an open surgical revision may be an alternative in the future.
In conclusion, PLE is a very rare presentation of HVOO following liver transplantation. This case highlights the need for an increased index of suspicion especially given the unusual presentation and normal duplex ultrasound findings here leading to delayed diagnosis. Management with venoplasty can be effective but repeated intervention may be necessary. The case also raises the question of whether a patient such as this should be screened regularly with venography to identify recurrence of the stenosis at the anastomotic site as duplex ultrasound was always unrevealing or whether it should be done based on symptomatology. If there are many further recurrences, this patient may eventually benefit from open surgical revision.