Splenic Abscess Treatment & Management

Once the diagnosis of a splenic abscess has been made, the patient must be admitted to the hospital and treated. Treatment depends on the patient's overall condition, comorbidities, and primary disorder (if any), as well as on the size and topography of the abscess. ^[31]

Empiric broad-spectrum antibiotic therapy has a primary role in the initial management of splenic abscesses. ^[5] The success of antibiotic therapy is not affected by the presence of multiple abscesses or by a polymicrobial flora. The choice of antibiotics is tailored to the culture results. Many splenic abscesses can be treated adequately without splenectomy. ^[38]

Percutaneous drainage has gained acceptance as an effective and less invasive treatment method than surgical intervention in selected patients. The reported success rate of percutaneous drainage ranges from 67% to 100%. Such drainage preserves the spleen and avoids the risk of overwhelming postsplenectomy sepsis (OPSS; also referred to as overwhelming postsplenectomy infection [OPSI]). Percutaneous drainage can also be used as a bridge to elective surgery in patients who are clinically unstable or in patients who have multiple comorbidities.

Early diagnosis and percutaneous drainage can increase the chance to preserve the spleen and, hence, its immunologic function. ^[39]

Percutaneous drainage is likely to be useful in patients who have unilocular or bilocular collections and if the character of the abscess content permits minimally invasive drainage. Multilocular abscesses, ill-defined cavities, septations, and necrotic debris typically do not respond to percutaneous drainage.

Surgery is reserved for patients who are stable and not amenable to percutaneous drainage. Depending on available expertise, laparoscopic or open procedures can be considered.

Contraindications for percutaneous drainage include the following ^{[9, 18, 31]} :

• Multiloculated or debris-filled abscess
• Multiple small abscesses
• Uncontrollable coagulopathy
• Poorly defined abscess on computed tomography (CT) or ultrasonography (US)
• Diffuse ascites
• No safe route for drainage

Relative contraindications for percutaneous drainage include the following:

• Splenic abscesses secondary to spread from a contiguous process, such as other large primary abscesses (eg, pancreatitis, perforated colon cancer) that cannot be eradicated by this method
• Abscess rupture
• A phlegmonous or poorly characterized lesion on CT or US

Endoscopic US-guided transluminal drainage of an aseptic splenic abscess has been reported. ^[40]

Early supportive care and parenteral broad-spectrum antibiotics are of paramount importance while further diagnostic and therapeutic arrangements are made. ^[3] Antibiotic coverage should target the presumed bacterial strains. Medical management as the only treatment of selected splenic abscesses has been advocated in several studies but remains controversial. The published literature suggests that most patients in this category have contiguous infections in the abdomen; the mortality in this group has been reported to be approximately 50%. ^[18]

Besides the more common organisms isolated from splenic abscesses, mycobacteria, Candida, and Aspergillus should also be considered; these organisms account for a small but significant number of splenic abscesses in patients who are immunocompromised. Fungal abscesses are known to respond more favorably to antifungal treatment, because they result more often from a disseminated infection. ^{[4, 11, 35]}

A retrospective multicenter French study of 10 pediatric and adult patients investigated the effect of corticosteroid therapy on individuals with symptomatic chronic disseminated candidiasis that persisted despite the administration of antifungal treatment. ^[41] In addition to finding evidence that corticosteroid therapy can effectively resolve the symptoms and inflammatory response associated with the infection, the study's authors reported that hepatosplenic microabscesses in the patients decreased or disappeared.

Surgical options

Invasive treatment of splenic abscess includes the following three options:

• Percutaneous drainage
• Open or laparoscopic splenectomy
• Open drainage

Percutaneous drainage

Percutaneous drainage is indicated for easily accessible uniloculated or biloculated abscesses with otherwise favorable features, as described previously, and also for surgical patients at very high risk who cannot tolerate general anesthesia or surgery. ^{[42, 43]}  The procedure includes a risk of iatrogenic injury of the spleen, colon (splenic flexure), stomach, left kidney, and diaphragm. ^[31]

Calcified walls of the abscess, the presence of other intra-abdominal cysts with intraluminal daughter cysts, and an origin from endemic areas (eg, the Mediterranean basin or Eastern Europe) should raise suspicion of Echinococcus granulosus. ^[10] Percutaneous drainage of such suppurative cysts increases the risk of hydatid seeding and anaphylaxis and is therefore contraindicated.

Other iatrogenic complications resulting from percutaneous drainage include hemorrhage, pleural empyema, pneumothorax, and enteric fistula. ^{[9, 44]}

Splenectomy

Splenectomy has long been considered the standard treatment of splenic abscess. Depending on the patient population, open splenectomy has a mortality of 0-17% and a morbidity of 28-43%. ^[45]  The procedure removes the septic source and the diseased organ. The surgeon can explore and manage coexisting septic collections.

Laparoscopic splenectomy is safe and effective in selected patients. It can be performed with no morbidity or mortality, and patients who have undergone the procedure reportedly have a shorter hospital stay. ^[32]

Very infrequently, the perisplenic adhesions are so severe that safe dissection between the spleen and the surrounding structures is impossible. The only choice in this scenario is to perform an open splenotomy and drain the collection.

Open drainage

Open drainage is used when the abscess cannot be drained percutaneously. Depending on the location of the abscess, one of the following three access routes can be employed:

• Transpleural - This usually requires resection of the 12th rib in the posterior axillary line and drainage of the abscess through the diaphragm
• Abdominal extraperitoneal - This accesses the abscess through the lateral abdominal wall and between the peritoneum and the flat abdominal muscles
• Retroperitoneal - This is used when the abscess extends to the flank

Operative details

The difficult location of the spleen increases the risk of iatrogenic hemorrhage or hollow-organ injury. Patients with splenic abscess must be typed and screened, and massive blood transfusion must be anticipated. Prophylactic broad-spectrum antibiotic coverage is essential. A nasogastric tube must be used to decompress the stomach. The risk of injury to the colon requires preoperative bowel preparation in nonemergency cases. Administration of polyvalent vaccines must be planned.

The operating room must be warm in order to decrease the risk of coagulopathy and wound infection. Blood products must be readily available.

A splenectomy can be performed through one of the following abdominal incisions:

• Midline incision - This is preferred in adult patients by most surgeons because it provides easy access to all four quadrants
• Left subcostal incision This spares the rectus abdominis (Singleton) and is preferred in pediatric patients
• Thoracoabdominal incision - Rarely, this is required in cases where massive pleural involvement by the abscess necessitates open thoracic access

Massive perisplenitis with adhesions carries a significant risk of iatrogenic splenic rupture. The spleen is mobilized carefully by dividing the ligamentous attachments. Special care must be taken to avoid injury to the pancreas and resulting pancreatic fistula.

In laparoscopic splenectomy, the spleen must be morcellated intra-abdominally to allow retrieval of the specimen through a limited incision. Prophylactic peritoneal drainage is at the discretion of the surgeon.

Because interventions for splenic abscess are potentially morbid, patients must be placed under close observation after the procedure, especially during the first 24 hours, when the risk of postoperative hemorrhage is high.

Mortality in patients with untreated splenic abscess approaches 100%. The list of complications is long but most importantly includes free rupture into the peritoneal cavity with generalized peritonitis, rupture into the colon, erosion of the abscess through the diaphragm, or, more rarely, necessitation through the skin.

Complications of treated splenic abscesses depend on the topography and treatment method. They can include the following:

• Life-threatening hemorrhage from the splenic parenchyma or hilar vessels
• Pneumothorax
• Left-side pleural effusion
• Subphrenic abscess
• Perforation of the colon, stomach, or small intestine
• Pancreatic pseudocyst or fistula
• Postsplenectomy thrombocytosis
• OPSS
• Atelectasis or pneumonia

Knowledge of the anatomy, careful preoperative planning, optimal exposure, and attention to the details of the technique can substantially reduce the incidence of iatrogenic complications. ^{[44, 31, 7]}

Respiratory complications are minimized or avoided by incentive spirometry and chest physical therapy.

Subphrenic abscess, though uncommon after splenic surgery, is a recognized consequence of pancreatic or hollow-organ injury. The condition requires prompt diagnosis and drainage.

In cases of splenectomy, thrombocytosis occurs in more than 50% of cases. A very high platelet count (>1,000,000/μL) necessitates intervention to minimize the incidence of thrombotic complications. Platelet apheresis or anticoagulants can be used in this regard.

OPSS carries a significant mortality risk, especially for young patients who have undergone splenectomy. Whenever splenectomy is considered, patients should undergo immunization against Streptococcus pneumoniae, Meningococcus, and Haemophilus influenzae type b. The administration of oral antibiotics to splenectomized individuals is the mainstay of prophylaxis (and initial therapy). Two complementary strategies are commonly used: daily antibiotic prophylaxis and empiric antibiotic therapy for fever.

Follow-up is an essential element of the management of patients undergoing treatment of splenic abscess. Patients must be screened for the following:

• Late iatrogenic complications, such as residual intra-abdominal abscesses, pancreatic or enteric collections, or fistulas
• Intestinal obstruction and ventral hernia
• Recurrent splenic abscess
• OPSS