Splenic Abscess As A Possible Sequel To COVID-19

Introduction:

The spleen is reported to be an unusual extrapulmonary organ affected by COVID-19. COVID-19 infection is caused by severe acute respiratory syndrome coronavirus (SARSCoV-2), a pandemic disease whose clinical manifestations and impact on human health are still being studied. The association between covid-19 and splenic abscess can be due to low immune status, hypercoagulation, and superinfection and occur as a possible sequela of COVID-19.

What Is A Splenic Abscess?

Splenic abscess is a rare condition that generally results from bacteremia. It is an infectious suppurative disease involving identifiable macroscopic filling defects in the spleen's parenchyma or the subcapsular space. Splenic abscess diagnosis is challenging and presents a triad of fever, left upper quadrant tenderness, and leukocytosis.

Splenic abscess is not frequent and occurs as a complication of infective endocarditis. The pathogens include Streptococcus, Staphylococcus, Mycobacterium, fungi, and parasites. The most common pathogen causing splenic abscess is Burkholderia pseudomallei in some parts of the world. The mortality rate is high with splenic abscess and fluctuating immune system and type of abscess.

What Are The Symptoms?

Symptoms of splenic abscess:

• Fever.

• Abdominal pain.

• Tender mass with palpation of left hypochondrium.

• Upper left quadrant tenderness.

• Leukocytosis.

• Edema of overlying soft tissue.

• Costovertebral tenderness.

• Splenomegaly.

• Left basilar rales.

• Dullness at the left lung base.

What Are The Causes Of A Splenic Abscess?

The possible causes of splenic abscess are described under five categories:

Intravenous Drug Use:

• Endocarditis.

• Salmonella infection.

• Osteomyelitis.

• Tuberculosis.

• Dental extractions.

• Infected intravascular devices.

Spread From Adjacent Organs: Through pancreatic abscess, gastric or colonic perforation.

Infection of Splenic Infarct: Hemoglobinopathies- sickle cell anemia and splenic artery embolization.

Immunocompromised Conditions: Cancer, diabetes mellitus, alcoholism, immunosuppressive treatment, and liver cirrhosis.

Can COVID-19 Cause Splenic Abscess?

SARS-CoV-2 infection may be associated with developing splenic abscesses related to hypercoagulability, low immunity, and superinfection. However, more studies are needed.

The COVID-19 infection reports that secondary bacterial infections are scarce, with a frequency of 4.8 to 15 %. The abscess or infection appears when the immune system is severely damaged and becomes inefficient due to lymphopenia and CD8-positive T-cell exhaustion, trying to compensate by triggering a cytokine storm that leads to potential complications.

Splenic artery embolization begins as an indication of splenic trauma in a hemodynamically stable patient experiencing platelet disorders to improve platelet count. Both carry a risk of developing an abscess. Therefore, studies were conducted and speculated that the direct cause of splenic abscess complication was the state of immunosuppression after a prolonged disease course.

COVID-19 as well can have a possible sequela on the body when compared with acute pancreatitis in terms of systemic inflammatory response and multiple organ involvement.

How Does COVID-19 Result In Splenic Abscess?

A splenic abscess can result in COVID-19 due to direct damage to the spleen caused by the virus or COVID-19-induced vasculitis and microvascular thrombosis. The COVID-19-induced hypercoagulable state leads to splenic artery thrombosis and splenic infarction due to splenic hypoperfusion.

The pyogenic splenic abscess is a rare infection in an immunocompromised patient. The splenic abscess in COVID-19 patients can be attributed to spleen necrosis caused by direct invasion of the COVID-19 virus, also resulting in variation of T and B lymphocyte depletion and lymphoid follicles atrophy.

Splenic abscess is uncommon and mostly associated with bacteremia or parasite infection. It follows a triad of fever, leukocytosis, and upper left quadrant abdominal pain. The exact sequela of COVID-19 is unknown. Abscess formation occurs due to microthrombi followed by endothelial destruction. These microthrombi are believed to cause splenic abscesses in non-vaccinated COVID-19-recovered patients.

How To Diagnose A Splenic Abscess?

The diagnosis of a splenic abscess is challenging and depends on the–

• Positive blood cultures and leukocytosis with a left shift.

• A plain chest X-ray reveals signs of splenic abscesses, such as elevated left hemidiaphragm and left-sided pleural effusion.

• Ultrasonogram reveals an area of decreased or absent splenomegaly and echogenicity.

• A CT scan is the definitive test for splenic abscess.

What Is The Treatment And Management Of Splenic Abscess?

Treatment and management include

• Hospitalization.

• High-dose parenteral broad-spectrum antibiotics.

• Splenectomy: surgical removal of the spleen.

• Percutaneous aspiration- less invasive abscess aspiration option in high-risk patients for surgery or life-threatening conditions.

• Percutaneous aspiration is the best option when the abscess collection is unilocular or bilocular, with a whole and thick wall and no internal septations.

• Aspiration is more accessible when the content of the abscess is liquid enough to be drained.

• In case of multiple collections or associated coagulopathy, laparoscopy or surgical treatment is preferred.

• Open drainage in case of unsuccessful percutaneous drainage.

• Corticosteroid therapy can be beneficial.

Contraindications:

• Percutaneous drainage– multiple small abscesses, debris-filled cavities. Poorly defined cavities, diffused ascites, coagulopathy, and difficult access.

• Antibiotics, mortality rates are higher with only antibiotic treatment.

• In patients with no response to antibiotics, one should consider fungi species are the cause of the splenic abscess.

Patient education:

• After splenectomy, patients have explained the precautions to take and follow-up.

• They need to understand that they are more prone to infections after spleen removal. Immunizations with primary healthcare providers should be discussed and reported for examination even at the slightest sign of cold or infection.

• If they are prescribed antibiotics for an infection, they are to be compliant and not vary from the course of treatment.

• Also, consider making an ID bracelet that indicates they had a splenectomy.

What Are The Possible Complications?

The complications include

• Pneumothorax.

• Atelectasis.

• Life-threatening hemorrhage.

• Left-sided pleural effusion.

• Subphrenic abscess.

• Perforation of the stomach, small bowel, or colon.

• Pancreatic fistula.

• Post splenectomy thrombocytosis.

• Pneumonia.

Respiratory complications are prevented by prescribing spirometry, pain control, and aggressive chest physical therapy.

Post-splenectomy sepsis is a potential risk, particularly in young individuals with the spleen removed. For patients who are advised for splenectomy, vaccination is done against meningococcus, Streptococcus pneumonia, and H. influenza

Conclusion:

COVID-19 infection is associated with the development of splenic abscess due to hypercoagulability, exhausted immunity, and superinfection. It is considered to be the cause when other etiological factors are absent. The diagnosis should be based on clinical and histopathological studies that show a clear pathophysiological association between COVID-19 and splenic abscesses. Early diagnosis and management are required for the optical outcome. In the absence of other etiologies, a recent history of Covid is considered the cause of splenic abscess.