Polysplenia syndrome in adult

Clinical History

A 37-year-old man presented with a 3-month history of general malaise, hyporexia, weight loss and progressive abdominal distension. He had no other illnesses and no remarkable family medical history.

Imaging Findings

An abdomen CT revealed hepatomegaly, multiple spleens in the left upper quadrant behind the stomach, an inferior vena cava interruption with an azygos continuation, preduodenal portal vein, a right-sided small bowel and left-sided large bowel. A short annular pancreas with a prominent head and no tail was evident.

Discussion

Polysplenia syndrome (PSS) is an unusual anomaly that arises in approximately 4 of every million live births [1].
It is a subtype of heterotaxy characterized by cardiac and vascular malformations, bilobed lung, visceral malrotation, multiple spleens and sometimes a short pancreas or agenesis of dorsal pancreas [2-5].
Only the 10% of the patients that do not have cardiac anomalies can reach adulthood [6].
The exact cause of polysplenia has not been defined.
The probable hypotheses are embryonic (accelerated curvature of the embryonic body), genetic causes and teratogenic factors [7].
There is slight female preponderance and rare familial association has also been found [7].
Cardiovascular anomalies associated with PSS include the absence or hypoplasia of the suprarenal inferior vena cava (with or without azygos or hemiazygos continuation), dextrocardia, ventricular septal defects, and morphologic left ventricular outflow obstruction. These anomalies result in patients death through congestive heart failure, hypoplastic left ventricle or morbidity of cardiac operation before the age of 5 [2]. Our patient did not have specific past history of heart disease.
The preduodenal portal vein (PDPV) is a portal vein located in front of the pancreatic head on CT. It passes ventral to the duodenum and the head of the pancreas. PDPV might interfere mechanically with pancreatic development, so it is associated with annular pancreas and malrotation [3] (as in the case of our patient). This vascular anomaly must be mentioned to prevent an accident during the pancreaticobiliary operation [8].
Abdominal complaints are the most frequent symptoms in adults, and sometimes CT shows intestinal malrotation. It is generally incidentally found in polysplenia but it can sometimes cause abdominal pain via recurrent volvulus or obstruction from a mesenteric band [9]. In some cases, pancreatitis with complete agenesis of the dorsal pancreas can cause abdominal pain [5].
Embryologically, the pancreas arises from ventral and dorsal buds. While the ventral bud forms the uncinate process and pancreatic head, the dorsal bud becomes the body and tail.
The dorsal pancreas and spleen develop in the dorsal mesogastrium. Therefore, concomitant anomalies of both organs can be expected in patients with PSS [4]. A short pancreas in PSS means partial agenesis or hypoplasia of the dorsal pancreas [10].
Plain chest X-ray and abdomen can give clues about abnormality in the chest and abdomen. CT, magnetic resonance imaging (MRI), angiography and echocardiography are important tools for ascertaining the location and number of spleens, location of other organs in the chest and abdomen, and identification of other associated anomalies.

Differential Diagnosis List

Final Diagnosis

Polysplenia syndrome

URL:	https://www.eurorad.org/case/12958
DOI:	10.1594/EURORAD/CASE.12958
ISSN:	1563-4086