Splenic Conditions

Asplenia and Polysplenia

Asplenia is often noted with complex congenital heart disease as well as bilateral “right-sidedness” such as bilateral three-lobed lungs, a right-sided stomach, and a central liver (Ivemark syndrome). Intestinal malrotation also has been observed with asplenia. These infants are at risk for overwhelming infection and should receive antibiotics for prophylaxis.

Polysplenia usually consists of a cluster of very small splenic masses and is often found with biliary atresia. Other associated conditions include a preduodenal portal vein, situs inversus, malrotation, and cardiac defects. In the instance of heterotaxy, the splenic mass(es) are always on one side of the body and along the greater curvature of the stomach. These children have adequate splenic immune function.

Wandering Spleen

This condition is characterized by a lack of ligamentous attachments to the diaphragm, colon, and retroperitoneum, resulting in a mobile spleen. This is likely due to failure of development of the splenic ligaments from the dorsal mesentery. Children can present with an abdominal mass and episodic pain, but they can also present acutely with torsion and infarction. Recently, two cases of portal/mesenteric varices were reported in adolescent patients, both of which resolved with splenectomy. Pancreatitis has also been noted as a presenting sign. Splenopexy is the preferred method of treatment and can be performed with placement of the spleen into a mesh basket, suture splenopexy, colonic displacement with gastropexy, positioning in an omental basket, or placement in an extraperitoneal pocket. The laparoscopic approach is the preferred technique, and the use of an absorbable or nonabsorbable mesh with fixation in the left upper quadrant is seen in Figure 47.1 . Placement of the spleen in an extraperitoneal pocket is seen in Figure 47.2 . Partial splenectomy and splenopexy also have been described. Torsion with infarction requires splenectomy. Cases of chronic torsion have also been reported with massive splenomegaly that may necessitate splenectomy.

Accessory Spleens

Accessory spleens have been noted in 15–30% of children, with a large series noting a 19% rate. Accessory spleens likely originate from mesenchymal remnants that fail to fuse with the main splenic mass. Most (75%) are located near the splenic hilum ( Fig. 47.3 ). Other locations that should be evaluated at the time of splenectomy include the lesser sac along the splenic vessels, omentum, and retroperitoneum. When found, most (86%) of accessory spleens are single, 11% have two, and 3% have three or more. A missed accessory spleen at the time of planned total splenectomy can lead to recurrence of the primary disease process, which in cases of immune thrombocytopenic purpura (ITP) is early and with hereditary spherocytosis (HS) is later.

Splenic Gonadal Fusion

This condition in which the left gonad and the spleen are attached is a result of early fusion between the two structures prior to descent of the testis. The remnant can be a continuous band or can be discontinuous with splenic tissue attached to the gonad. A splenic remnant also has been noted in the left scrotum as an accessory splenic remnant type of abnormality.

Splenic Cysts

Cysts of the spleen are most frequently primary splenic cysts containing an epithelial lining ( Fig. 47.4 ). They are also referred to as epithelial or epidermoid cysts. Post-traumatic pseudocysts are occasionally seen. Inclusion of surface mesothelium into the splenic parenchyma is the most likely etiology of epithelial cysts. Patients may present with symptoms related to their size with gastric compression or pain, an abdominal mass, rupture, or infection with an abscess. Simple cysts less than 5 cm can be observed, but cysts that are enlarging, symptomatic, or larger than 5 cm usually require treatment. Most symptomatic cysts are larger than 8 cm. Percutaneous aspiration and sclerosis utilizing alcohol or other agents have been reported with variable success. A recent study showed sclerosis with alcohol caused disappearance in 20% of patients. In this study, in patients with symptoms, 67% had symptom resolution with cysts larger than 5 cm.

Marsupialization is commonly performed but has been associated with a high recurrence rate if an adequate amount of cyst wall is not removed ( Fig. 47.5 ). In addition, a high recurrence rate with laparoscopic partial excision has also been observed. However, others have had good success with this technique. Some authors recommend partial splenectomy associated with cyst resection. Our group has reported good results with partial splenectomy, emphasizing resection of a margin of normal spleen so that the cut surfaces cannot oppose, which might lead to recurrence. Other techniques involve lining the cyst with Surgicel (Ethicon, Inc., Somerville, NJ) and omentopexy.