Hemochromatosis type 4 is a hereditary iron overload disorder that affects ferroportin, an iron transport protein needed to export iron from cells into circulation. Although the disease is rare, it is found throughout the world and affects people from various ethnic groups. While the majority of individuals with type 4 hemochromatosis have a relatively mild form of the disease, some affected individuals have a more severe form. As the disease progresses, iron may accumulate in the tissues of affected individuals over time, potentially resulting in organ damage. Signs and symptoms
Symptoms vary greatly between individuals with type 4 hemochromatosis. This difference in symptoms is likely due to the different types of SLC40A1 mutations patients may have. In general, signs and symptoms of type 4 hemochromatosis are caused by excess iron in cells, which leads to tissue damage. The damage is largely due to iron-catalyzed oxidative reactions. Iron can exchange electrons with a variety of substrates, which can lead to generation of reactive oxygen species. This can lead to oxidative stress, lipid peroxidation, and DNA damage, which may result in cell death. Two main forms of hemochromatosis type 4 exist (A and B), and the symptoms of these forms are distinct from one another.Type 4A hemochromatosis typically has milder symptoms than other types of hemochromatosis. Individuals with type 4A hemochromatosis tend to have hyperferritinemia (elevated ferritin in the blood plasma) and low saturated transferrin levels. These individuals are likely to have liver and spleen iron overload, primarily in Kupffer cells and other macrophages.
Infestation is the state of being invaded or overrun by pests or parasites. It can also refer to the actual organisms living on or within a host. Terminology
In general, the term "infestation" refers to parasitic diseases caused by animals such as arthropods (i.e. mites, ticks, and lice) and worms, but excluding (except) conditions caused by protozoa, fungi, bacteria, and viruses, which are called infections. External and internal
Infestations can be classified as either external or internal with regards to the parasites location in relation to the host. External or ectoparasitic infestation is a condition in which organisms live primarily on the surface of the host (though porocephaliasis can penetrate viscerally) and includes those involving mites, ticks, head lice and bed bugs.An internal (or endoparasitic) infestation is a condition in which organisms live within the host and includes those involving worms (though swimmers itch stays near the surface). Medically, the term "infestation" is often reserved only for external ectoparasitic infestations while the term infection refers to internal endoparasitic conditions. References
External links
Introduction to Anaerobic Soil Disinfestation as a Fumigant Alternative
New technique predicts risk of plant disease and infestation