The accessory spleen: prevalence and imaging findings in 1,735 consecutive patients examined by multidetector computed tomography

OBJECTIVE

To analyze the prevalence and CT findings of accessory spleens in the normal population.

MATERIAL AND METHODS

CT-examinations of 1735 consecutive patients, all examined by triple phase 16-row multidetector computed tomography (MDCT) of the abdomen, were retrospectively analyzed with special emphasis on the presence, location and imaging aspects of accessory spleens.

RESULTS

199 patients showed an accessory spleen (11%). Size of accessory spleens ranged from 3 to 20 mm (mean 10 mm). In 60% the accessory spleen was located at the level of the splenic hilum and in 33% at the level of the lower pole. In 46% the accessory spleen was located medially and in 43% ventrally. 19 patients presented with two (1.1%) and seven patients with three accessory spleens (0.4%), respectively. One patient showed splenosis and one patient showed an enlarged accessory spleen (5 cm) secondary to a splenic apoplexy (i.e. hemorrhagic infarction) of the accessory spleen, caused by torsion.

CONCLUSION

Accessory spleens may be identified by MDCT in about 11% of patients. Familiarity with normal imaging findings and knowledge on differential diagnoses, possible pathologies and potential pitfalls helps to differentiate from other findings in the upper abdomen.

Intrapancreatic accessory spleen

A case of accessory spleen located in the tail of the pancreas in a stillbirth male foetus is reported. The congenital anomaly was revealed at autopsy. The intrapancreatic spleen was well demarcated and was composed of red and white pulp; however, same pancreatic ducts were intermingled with the splenic parenchyma. As well as the intrapancreatic lesion another minute accessory spleen was also found at the hilum of the proper organ. Since a lack of morphological features of trisomy 13 syndrome were found in the foetus, the ectopic spleens were regarded as incidental findings.

[Prevention of severe infections in patients with hyposplenism or asplenia]

Each year, up to a 1000 splenectomies are performed in the Netherlands. Aside from patients without a spleen, there is also a large group of patients with hyposplenism or functional asplenia due to other primary diseases. All these patients are at risk of developing severe infections, such as post-splenectomy sepsis (PSS), which is associated with very high mortality. However PSS can partly be prevented by taking simple measures such as immunizations and prophylactic or early use of antibiotics. Healthcare professionals in first and secondary care in the Netherlands are generally not well informed about which preventive measures should be taken to prevent these infections, resulting in often suboptimal management of patients. In this article, recommendations are given on vaccination and administration of antibiotics to prevent severe infections such as PSS in this group of patients.

Splenogonadal fusion and sex reversal

Splenogonadal fusion is a rare congenital malformation where an abnormal union occurs between the spleen and gonad or mesonephric derivatives. Although it occurs in females it is much less prevalent than in males (male:female ratio, 16:1), but this may partly be because of the inaccessibility of the female gonads leading to under-diagnosis. To our knowledge this is the first case of splenogonadal fusion associated with sex reversal reported in the literature.

Intrapancreatic accessory spleen: investigative dilemmas and role of EUS-guided FNA for diagnostic confirmation

CONTEXT

We submit a case of intrapancreatic accessory spleen.

CASE REPORT

A 33-year-old patient with history of dyspepsia underwent imaging studies suggestive of a neuroendocrine tumor. After referral to our institute, endoscopic ultrasound guided fine needle aspiration (EUS-FNA) confirmed diagnosis as intrapancreatic accessory spleen.

DISCUSSION

An accessory spleen may develop from estranged mesenchymal cells due to fusion failure of the splenic anlage. The prevalence of an accessory spleen is 10-30% with 80% of them present at the splenic hilum and 17% in the pancreatic tail. Intrapancreatic accessory spleen is commonly misdiagnosed as a pancreatic tumor. Since, the differential diagnosis includes pancreatic neuroendocrine tumors, additional investigation with EUS-FNA should be considered when radiological diagnosis is not definitive.

CONCLUSION

For diagnosis of intrapancreatic accessory spleen, radiographic imaging is useful, but lacks specificity without tissue diagnosis. Diagnosis can be safely and reliably established with EUS-FNA, leading to a benign prognosis and avoidance of unnecessary surgical intervention.

Biliary atresia with associated structural malformations in Canadian infants

BACKGROUND

Biliary atresia (BA) is associated with extrahepatic congenital malformations in a minority of affected infants. The term commonly applied to this subgroup is 'BASM' for biliary atresia splenic malformation syndrome, as spleen abnormalities are prominent.

AIMS AND METHODS

To examine clinical outcome in Canadian BA patients with extrahepatic congenital malformations in the Canada-wide BA database of patients born between 1985 and 2002, and additionally, to recharacterized the syndrome. Patients had ≥1 of the following: a/polysplenia, abnormal abdominal situs, intestinal malrotation, abdominal vascular anomaly or congenital heart disease.

RESULTS

Among 328 BA patients, 44 (13%) had associated congenital abnormalities. Intra-abdominal anomalies included polysplenia (n=25), abnormal abdominal situs (n=9), intestinal malrotation (n=19), portal vein anomaly (n=12), hepatic artery anomaly (n=3) and inferior vena cava interruption (n=20). Twenty-six patients had cardiac malformations including pulmonary stenosis (n=11), ventricular septal defect (n=10), atrial septal defect (n=7), total anomalous pulmonary venous return (n=3), double outlet right ventricle (n=3), tetralogy of Fallot (n=2), atrioventricular canal (n=2), dextrocardia (n=2), bicuspid aortic valve (n=2), hypoplastic left heart (n=1) and partial anomalous pulmonary venous return (n=1). Age at Kasai operation, performance of liver transplant, overall survival, post-Kasai native liver survival and transplant survival were comparable to isolated BA. Presence of polysplenia or complex cardiac disease did not reduce post-Kasai native liver survival. Three patients had ≥2 typical abnormalities without polysplenia: thus, splenic malformations are not essential to this BA subgroup. Hierarchical cluster analysis demonstrated characteristic abnormalities grouped in a multiplicity of combinations, consistent with a spectrum of defective lateralization.

CONCLUSION

We suggest that the acronym 'BASM' be redefined as 'biliary atresia structural malformation'.

Role of four-dimensional ultrasound (spatiotemporal image correlation and sonography-based automated volume count) in prenatal assessment of atrial morphology in cardiosplenic syndromes

OBJECTIVE

To assess the diagnostic role of four-dimensional ultrasound using spatiotemporal image correlation and Sonography-based Automated Volume Count (STIC-SonoAVC) in the identification of the morphology of the atrial appendages in cases with cardiosplenic syndrome.

METHODS

This was a retrospective investigation of 22 fetuses with cardiosplenic syndromes seen at our institution over a 5-year period from January 2004. As control groups, 10 normal fetuses, five cases with a non-isomeric atrioventricular septal defect and five cases with other congenital heart diseases were also analyzed. For all fetuses, one or more cardiac volume datasets were available for offline analysis. Two-dimensional and four-dimensional echocardiography was carried out in all cases at the time of diagnosis using high quality three-dimensional equipment. Dedicated software was used to assess chamber morphology using the SonoAVC technique, which allows the creation of casts of hollow structures. Two different operators used the software. The first performed all steps up to positioning of the region of interest box. The second operator, who was blinded to clinical information, then rendered the cardiac chambers using the SonoAVC technique. This operator then used the rendered image to subjectively assess atrial morphology.

RESULTS

Suitable rendered images of the cardiac chambers could be produced in 40/42 fetuses. In two cases of left atrial isomerism, advanced (34 weeks) and early (13 weeks) gestational age made it impossible to obtain adequate rendered images. In the remaining 40 cases (13 cases of left atrial isomerism, seven cases of right atrial isomerism, five cases of non-isomeric atrioventricular septal defect, five cases of other congenital heart diseases and 10 normal fetuses), atrial morphology was correctly identified by evaluation of the rendered images.

CONCLUSION

Four-dimensional ultrasound with SonoAVC rendering allows correct identification of the morphology of atrial appendages in all cases of cardiosplenic syndromes in which an adequate cardiac volume dataset can be obtained for analysis.

Post-splenectomy and hyposplenic states

The spleen is crucial in regulating immune homoeostasis through its ability to link innate and adaptive immunity and in protecting against infections. The impairment of splenic function is defined as hyposplenism, an acquired disorder caused by several haematological and immunological diseases. The term asplenia refers to the absence of the spleen, a condition that is rarely congenital and mostly post-surgical. Although hyposplenism and asplenia might predispose individuals to thromboembolic events, in this Review we focus on infectious complications, which are the most widely recognised consequences of these states. Because of the high mortality, the fulminant course, and the refractoriness to common treatment of overwhelming infections caused by encapsulated bacteria, prevention through vaccination and antibiotic prophylaxis is the basis of the management of patients who have had splenectomy or have hyposplenism. In this Review, we critically assess clinical and diagnostic aspects of splenic dysfunction and highlight new perspectives in the prevention of overwhelming post-splenectomy infections.

Developmental and posthatch effects of in ovo exposure to 2,3,7,8-TCDD, 2,3,4,7,8-PECDF, and 2,3,7,8-TCDF in Japanese quail (Coturnix japonica), common pheasant (Phasianus colchicus), and white leghorn chicken (Gallus gallus domesticus) embryos

An egg injection study was conducted to confirm a proposed model of relative sensitivity of three avian species to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-like chemicals. It was previously reported that the order of species sensitivity to in ovo exposure to TCDD, 2,3,4,7,8-pentachlorodibenzofuran (PeCDF), or 2,3,7,8-tetrachlorodibenzofuran (TCDF) at doses ranging from 0.044 to 37 picomoles (pmol)/g egg was the chicken (Gallus gallus domesticus), common pheasant (Phasianus colchicus), and Japanese quail (Coturnix japonica) based on embryo mortality and hepatic enzyme induction. In the present study, the incidence of developmental deformities, changes in body and relative organ masses, and organ pathology of hatchlings as additional indicators of species sensitivity were assessed; in addition, embryo mortality in the three species was categorized by stage of development. Embryo mortality varied temporally with significant increases generally occurring after organogenesis and just prior to hatching. A significant increase in the percentage of developmental deformities was observed only in Japanese quail exposed to TCDF. Body and relative organ masses of quail, pheasants, and chickens dosed in ovo with TCDD, PeCDF, or TCDF were not consistently affected. Chemical-related pathology occurred only in livers of quail at the greatest doses of each compound. These results indicated that the incidence of developmental deformities, changes in body and relative organ masses and organ pathology could not be used as indicators of species sensitivity or chemical potency.

[Sudden abdominal pain...is it a surprise? Necrosis of an ectopic spleen]

An ectopic/wandering spleen is rare in children. It results from the absence or laxity of the supporting ligaments which may cause torsion of the splenic pedicle with subsequent infarction. We present a case of a six-year-old girl, with history of onphalocele, dextrocardia and ectopic spleen (incidentally discovered three years ago as an abdominal mass on physical examination), with acute abdominal pain and signs of peritoneal irritation. Sonography showed an enlarged ectopic spleen in the pelvis. Computed tomography scan did not enable visualization of the spleen and allowed the identification of a pelvic mass without uptake of intravenous contrast. Splenectomy was performed due to splenic infarction. In the presence of a wandering spleen, even if asymptomatic, splenopexy may be performed to minimize complications, and together with acute abdominal pain, torsion of splenic pedicle may be considered.

Pre-duodenal portal vein in polysplenia syndrome: clinical effects and surgical application

STATING BACKGROUND: Pre-duodenal portal vein (PPV) is a rare congenital anomaly, usually asymptomatic and thus detected only incidentally in adults. It is often associated with other anomalies which can be included into polysplenic syndrome.

METHODS

In this case, a 56-year-old-female was admitted for a degenerative ampullome. The preoperative work-up shows a PPV vein, the absence of inferior vena cava retro-hepatic and the presence of an anastomosis between the inferior vena cava and the azygos system and a complete common mesentery.

DISCUSSION

Such a discovery is often incidental and of little import; however, it takes on major importance for surgeons because the accidental damage of PPV can lead to serious consequences.

CONCLUSION

The aim of this study, based on the embryology of the portal vein focused on a rare anomaly to keep it in mind because this anomaly in case of digestive surgery may need to adjust surgical techniques.

Epithelial cyst arising in an intrapancreatic accessory spleen: a diagnostic dilemma

An epithelial cyst in an intrapancreatic accessory spleen (ECIAS) is a rare disease that is commonly misdiagnosed preoperatively. To identify the clinical and imaging features of ECIAS, we reviewed the relevant medical literature. Twenty-one cases of ECIAS were identified, including our own. The cases were mainly diagnosed as mucinous cystic neoplasm (MCN) preoperatively based on clinical and imaging features, such as, a woman in middle age; elevation of serum CA19-9 levels; location in the tail of the pancreas; and a solid component resembling a mural nodule. ECIAS is another lesion to be considered in the differential diagnosis of MCN.

Cloacal exstrophy: a case report and literature review

Cloacal exstrophy is an extremely rare congenital malformation resulting in an exstrophy of the urinary, intestinal, and genital organs and associated with anomalies of other organ systems. We present a complicated case of cloacal exstrophy and the recent progress in the management of this probably most complicated anomaly in pediatric urology and surgery.

Isolated congenital asplenia: a French nationwide retrospective survey of 20 cases

OBJECTIVE

To better describe the natural history, mode of inheritance, and the epidemiological and clinical features of isolated congenital asplenia, a rare and poorly understood primary immunodeficiency.

STUDY DESIGN

A French national retrospective survey was conducted in hospital pediatric departments. A definitive diagnosis of ICA was based on the presence of Howell-Jolly bodies, a lack of detectable spleen, and no detectable cardiovascular malformation.

RESULTS

The study included 20 patients (12 males and 8 females) from 10 kindreds neither related to each other nor consanguineous. The diagnosis of ICA was certain in 13 cases (65%) and probable in 7 cases (35%). Ten index cases led to diagnosis of 10 additional cases in relatives. Five cases were sporadic and 15 were familial, suggesting autosomal dominant inheritance. Median age was 12 months at first infection (range, 2-516 months), 11 months at diagnosis of asplenia (range, 0-510 months), and 9.9 years at last follow-up (range, 0.7-52 years). Fifteen patients sustained 18 episodes of invasive bacterial infection, caused mainly by Streptococcus pneumoniae (61%). Outcomes were poor, with 9 patients (45%) dying from fulminant infection.

CONCLUSIONS

ICA is more common than was previously thought, with an autosomal dominant inheritance in at least some kindreds. Relatives of cases of ICA should be evaluated for ICA, as should children and young adults with invasive infection.

Liver transplantation in children with biliary atresia and polysplenia syndrome

BACKGROUND

Children with biliary atresia and polysplenia syndrome (BA-PS) have always been considered as high risk liver transplant recipients due to technical problems during transplant surgery. We report single-center experience with liver transplantation in children with this syndrome.

MATERIAL/METHODS

Between 2000 and 2010, 401 liver transplantations were performed in 358 children, including 6 patients with BA-PS, who underwent living (5 patients) or deceased (1 patient) donor liver transplantation. Patients demonstrated various malformations: absence of retrohepatic vena cava (3), intestinal malrotation (3), preduodenal portal vein (1), hepatic artery anomalies (3), cardiac anomalies (2), and situs inversus (1). Transplantations were performed at the patient age of 8 months to 11 years.

RESULTS

There were no serious technical problems during the operations, and we did not have to use vascular conduits for graft revascularization in any case. All patents were alive at follow-up between 14 and 123 months after transplantation (mean 75 months). We observed, however, increased incidence of PV thrombosis and biliary complications in these patients, which did not influence patient and graft survival. In 1 child with graft failure due to chronic rejection after discontinuation of immunosuppression due to PTLD, retransplantation was performed.

CONCLUSIONS

Results of liver transplantation in children with BA-PS are as good as for other indications and non-syndromic BA in an experienced pediatric liver transplant center. Although there were no serious technical problems during deceased or living related donor transplantation in these children, close observation for possible vascular complications should be the routine in the postoperative period.

Unusual presentation of biliary atresia splenic malformation syndrome with autosomal dominant hypospadias

Biliary atresia is associated with polysplenia in 2-10% of cases and is defined as Biliary Atresia Splenic Malformation syndrome (BASM). The main features of BASM syndrome include extrahepatic biliary atresia and polysplenia besides the characteristic findings of laterality anomalies, cardiac anomalies, intraabdominal vascular anomalies, pancreatic anomalies and malrotation. Here we present a 6-month-old male patient with BASM having atrial septal defect, umblical hernia, inguinal hernia, and hypospadias. Clinical history revealed that his father also had hypospadias which showed a rare form of autosomal dominant inheritance. The karyotype was normal and the molecular analysis of CFC1 gene revealed no mutation. We emphasize the importance of a detailed physical examination in cases with BASM.

Splenogonadal fusion: a case report

Splenogonodal fusion is a rare congenital abnormality. We present the case of a continuous splenogonadal fusion diagnosed in the course of a laparoscopy for left non-palpable testis in a 1-year-old boy. This case illustrates that even though testicular salvage is the recommended approach, various anatomical features might preclude conservation.

Infarcted accessory spleen due to segmental portal hypertension

Accessory spleens are frequent entities, but their infarction due to arterial stasis caused by segmental portal hypertension is extremely rare. We present this case of a 38-year-old female patient with a three-week history of abdominal pain and an abdominal CT scan revealing a 7 cm mass near the spleen and tail of pancreas with segmental portal hypertension. The patient had no hematologic disease. This mass was surgically resected, with a pathological diagnosis of an infarcted accessory spleen.

[Isolated congenital asplenia--a rare cause of severe pneumococcal sepsis]

Invasive disease caused by Streptococcus pneumoniae (SPn) is common among young children. Severe sepsis can be seen among those with primary or secondary immunodeficiency states. The absence of a spleen is a well-known risk factor for severe and overwhelming pneumococcal sepsis, as well as other encapsulated bacteria (e.g. Haemophilus influenzae type b (Hib), or Neisseria meningitidis). The most common cause of asplenia is surgical removal of the spleen (after trauma or as a treatment for various hematological conditions). Dysfunction of the spleen can also be seen in sickle cell disease, with high risk of invasive bacterial diseases. Primary congenital asplenia is rare. Congenital asplenia can be a part of Ivemark syndrome which is accompanied by other malformations. Isolated congenital asplenia is exceedingly rare. These patients can present with severe sepsis, meningitis or even sudden death. Overall, 31 cases have been reported, among them 17 were familial and the rest sporadic. The genetic bases for this rare life-threatening malformation are not known. The authors describe a one year old patient, presented with severe pneumococcal sepsis and multisystem organ failure. Isolated congenital asplenia was demonstrated. The child recovered and is being treated according to the recommendations for adults with asplenia.