SMV and portal vein thrombosis in hypereosinophilic syndrome

Clinical History

22-year-old male patient with reddish itchy lesions for 2 weeks. Patient also had superficial thrombophlebitis of the long saphenous vein in the right leg and upper abdominal pain for which he was referred for a CT abdomen. Laboratory results showed absolute eosinophilic count of 10,300 /mm3

Imaging Findings

Contrast enhanced CT abdomen showed linear filling defects in the portal vein with multiple collaterals at the porta hepatis suggestive of portal cavernoma secondary to thrombosis. Altered enhancement pattern noted in the liver suggestive of transient hepatic attenuation difference (THAD). Filling defect noted in the superior mesenteric vein in the proximal segment with streaky filling in the distal segment suggestive of thrombosis. Head of pancreas appeared mildly bulky. Mild oedema in the jejunal loops noted with prominent valvulae conniventes and vascular congestion in the mesentry secondary to SMV thrombosis.

Patchy areas of consolidation noted in bilateral lung basal segments with a predominant peripheral distribution.

The patient also had superficial thrombophlebitis of the right long saphenous vein on venous Doppler study.

Extensive laboratory investigations ruled out secondary causes for eosinophilia confirming the diagnosis of idiopathic hypereosinophilic syndrome.

Discussion

Idiopathic hypereosinophilic syndrome (IHS) is a group of conditions with increased peripheral eosinophil count without an obvious underlying factor [1, 2]. The criteria for diagnosis of idiopathic hypereosinophilic syndrome is a peripheral eosinophil count more than 1500 eosinophils/mm3 for more than six months without any evidence of parasitic infection, allergic cause or other any condition which can raise eosinophil counts. There should also be evidence of organ involvement. Various organs and systems can get affected if infiltrated by eosinophils. The ones that are commonly documented include the cardiovascular system, respiratory system, haematopoietic system, liver, spleen, bowel and central nervous system [1, 2]. Liver involvement has been reported in many cases of idiopathic hypereosinophilic syndrome on ultrasonography and Computed Tomography [1, 2]. These patients show hepatomegaly and abnormal liver function test on ultrasonography and biochemical investigations respectively with evidence of small low attenuation lesions scattered throughout the liver predominantly in the periportal regions with narrowing of the intrahepatic portal veins [1, 2, 3, 4]. However, portal, splenic and mesenteric vein thrombosis is a rarer occurrence in hypereosinophilic syndrome.

There are many causes for portal vein thrombosis like cirrhosis of liver with portal hypertension, hepatocellular carcinoma, myeloproliferative disorders and deficiency of natural anticoagulant proteins [5]. IHS is a rare cause of hypercoagulability which in turn can cause portomesentric and splenic vein thrombosis leading to acute or subacute intestinal angina as a clinical manifestation [6]. Oedema of the bowel wall in such cases is a result of venous congestion secondary to the portomesenteric thrombosis.

Other sites of venous thrombosis documented in hypereosinophilic syndromes include intracardiac (prosthetic valves), superficial veins in the legs and intracranial dural venous sinuses.

CT findings in the thorax in hypereosinophilic syndromes include consolidation/ ground glass attenuation with a predominant peripheral distribution [7].

Early diagnosis and treatment of portomesenteric and splenic vein thrombosis in hypercoagulable syndromes such as IHS is important to avoid complications such as ischaemia/ infarction of the bowel.

Differential Diagnosis List

Final Diagnosis

SMV and portal vein thrombosis in hypereosinophilic syndrome

URL:	https://eurorad.org/case/9917
DOI:	10.1594/EURORAD/CASE.9917
ISSN:	1563-4086