How does the spleen destroy encapsulated bacteria?

The spleen contains many macrophages (part of the reticuloendothelial system), which are immune cells that phagocytose (eat) and destroy bacteria. In particular, these macrophages are activated when bacteria are bound by IgG antibodies (IgG1 or IgG3) or the complement component C3b.

Which organism causes infection after splenectomy?

Overwhelming post-splenectomy infection is usually caused by the encapsulated bacteria Streptococcus pneumoniae, Haemophilus influenzae, and Neisseria meningitidis and more than half of those infected die.

Why is spleen important for encapsulated bacteria?

Conclusion. The spleen is crucial to the host response to infection by clearing polysaccharide-encapsulated bacteria. This response involves the clearing of pathogens from the bloodstream as well as the rapid production of specific antigens.

Why are encapsulated bacteria more pathogenic?

The encapsulation makes bacteria more pathogenic. It protects bacteria from phagocytosis by macrophages. Capsule increases tolerance from desiccation. It helps bacteria adhere to surfaces.

What is functional asplenia?

Functional asplenia refers to complete loss of function caused by medical conditions and occurs most frequently with sickle cell anemia [2]. Rarely, the spleen is congenitally absent.

Does asplenia cause immunocompromised?

1,2 Patients who have had a splenectomy or have functional asplenia are immunocompromised and are at increased risk for severe and overwhelming bacterial infections, particularly from encapsulated bacteria. These bacterial infections are more likely to occur in patients with viral infections.

Is spleen encapsulated?

The spleen has an abundance of lymphoid tissue, including splenic macrophages that attack encapsulated organisms. In their absence, the ability to fight off these pathogens is severely diminished.

What antibiotics cover encapsulated organisms?

The aim of medical therapy is to prevent invasive disease secondary to polysaccharide-encapsulated organisms, especially pneumococci. Penicillin and amoxicillin are currently the drugs of choice.

What does functional asplenia mean?

Asplenia is the absence of normal spleen function ( functional asplenia. ) or of the spleen itself (anatomic asplenia). Anatomic asplenia is most commonly due to elective or emergency.

How does bacterial capsule prevent phagocytosis?

Capsules can protect a bacterial cell from ingestion and destruction by white blood cells (phagocytosis). While the exact mechanism for escaping phagocytosis is unclear, it may occur because capsules make bacterial surface components more slippery, helping the bacterium to escape engulfment by phagocytic cells.

Why is capsulated bacteria more virulent than non capsulated bacteria?

The capsule is considered a virulence factor because it enhances the ability of bacteria to cause disease (e.g. prevents phagocytosis). The capsule can protect cells from engulfment by eukaryotic cells, such as macrophages. A capsule-specific antibody may be required for phagocytosis to occur.

What encapsulated bacteria?

The term ‘encapsulated bacteria’ refers to bacteria covered with a polysaccharide capsule. Examples of such bacteria include Streptococcus pneumoniae, Klebsiella, Haemophilus influenzae, Neisseria meningitidis, and Pseudomonas aeruginosa.

Which are the encapsulated organisms?

The encapsulated bacteria Streptococcus pneumoniae, Neisseria meningitis, Haemophilus influenzae, and Streptococcus agalactiae (Group B Streptococcus) have been responsible for the majority of severe infections in children for decades, specifically bacteremia and meningitis.

What happens if you get an infection without a spleen?

Long-term risk of infection After spleen removal, you’re more likely to contract serious or life-threatening infections. Your doctor may recommend that you receive vaccines against pneumonia, influenza, Haemophilus influenzae type b (Hib) and meningococci.

Does not having a spleen make you more susceptible to COVID-19?

For most viruses, not having a spleen does not seem to be a major risk factor for illness. So far this seems to be true for COVID-19 as well. New studies are being published constantly, but lack of a spleen has not been identified as a risk factor for acquiring COVID-19 or having worse outcomes.