Isolated congenital asplenia is a rare disease in humans that can cause life-threatening

bacterial infections Pathogenic bacteria are bacteria that can cause disease. This article focuses on the bacteria that are pathogenic to humans. Most species of bacteria are harmless and are often beneficial but others can cause infectious diseases. The number of t ...

in children due to

primary immunodeficiency Primary immunodeficiencies are disorders in which part of the body's immune system is missing or does not function normally. To be considered a ''primary'' immunodeficiency (PID), the cause of the immune deficiency must not be secondary in nature ...

. The infections can include pneumococal

sepsis Sepsis, formerly known as septicemia (septicaemia in British English) or blood poisoning, is a life-threatening condition that arises when the body's response to infection causes injury to its own tissues and organs. This initial stage is follo ...

and

meningitis Meningitis is acute or chronic inflammation of the protective membranes covering the brain and spinal cord, collectively called the meninges. The most common symptoms are fever, headache, and neck stiffness. Other symptoms include confusion or ...

. ICAS is a

ribosomopathy Ribosomopathies are diseases caused by abnormalities in the structure or function of ribosomal component proteins or rRNA genes, or other genes whose products are involved in ribosome biogenesis. Ribosomes Ribosomes are essential for protein synt ...

, due to

autosomal dominant In genetics, dominance is the phenomenon of one variant (allele) of a gene on a chromosome masking or overriding the effect of a different variant of the same gene on the other copy of the chromosome. The first variant is termed dominant and t ...

mutation In biology, a mutation is an alteration in the nucleic acid sequence of the genome of an organism, virus, or extrachromosomal DNA. Viral genomes contain either DNA or RNA. Mutations result from errors during DNA or viral replication, mi ...

of the ''

RPSA 40S ribosomal protein SA is a ribosomal protein that in humans is encoded by the ''RPSA'' gene. It also acts as a cell surface receptor, in particular for laminin, and is involved in several pathogenic processes. Function Laminins, a family of ...

gene In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a ba ...

chromosome 3 Chromosome 3 is one of the 23 pairs of chromosomes in humans. People normally have two copies of this chromosome. Chromosome 3 spans almost 200 million base pairs (the building material of DNA) and represents about 6.5 percent of the total DNA in ...

p21. Unlike

heterotaxy syndrome Situs ambiguus is a rare congenital defect in which the major visceral organs are distributed abnormally within the chest and abdomen. Clinically heterotaxy spectrum generally refers to any defect of Left-right asymmetry and arrangement of the visc ...

, the absent spleen (asplenia) is not associated with other structural developmental defects. In some cases the

spleen The spleen is an organ found in almost all vertebrates. Similar in structure to a large lymph node, it acts primarily as a blood filter. The word spleen comes .

is present, but very small and nonfunctional (hyposplenism).

Immunodeficiency

The spleen is an organ within the

lymphatic system The lymphatic system, or lymphoid system, is an organ system in vertebrates that is part of the immune system, and complementary to the circulatory system. It consists of a large network of lymphatic vessels, lymph nodes, lymphatic or lymphoid o ...

and its primary function is to filter blood. However, the spleen also plays a key role in

immune In biology, immunity is the capability of multicellular organisms to resist harmful microorganisms. Immunity involves both specific and nonspecific components. The nonspecific components act as barriers or eliminators of a wide range of pathogens ...

responses as it detects pathogens within the blood and secretes

phagocytes Phagocytes are cells that protect the body by ingesting harmful foreign particles, bacteria, and dead or dying cells. Their name comes from the Greek ', "to eat" or "devour", and "-cyte", the suffix in biology denoting "cell", from the Greek '' ...

to fight potential infection. Without these immune functions, individuals with isolated congenital asplenia are extremely susceptible to infection. ''

Streptococcus pneumoniae ''Streptococcus pneumoniae'', or pneumococcus, is a Gram-positive, spherical bacteria, alpha-hemolytic (under aerobic conditions) or beta-hemolytic (under anaerobic conditions), aerotolerant anaerobic member of the genus Streptococcus. They are ...

'' is a common bacteria that affects individuals with ICAS, often causes meningitis, sepsis, and

otitis media Otitis media is a group of inflammatory diseases of the middle ear. One of the two main types is acute otitis media (AOM), an infection of rapid onset that usually presents with ear pain. In young children this may result in pulling at the ear, ...

References

{{DEFAULTSORT:Isolated congenital asplenia Congenital disorders Immunodeficiency Ribosomopathy