Late AMD
In late AMD, enough retinal damage occurs that, in addition to drusen, people will also begin to experience symptomatic central vision loss. The damage can either be the development of atrophy or the onset of neovascular disease. Late AMD is further divided into two subtypes based on the types of damage: Geographic atrophy and Wet AMD (also called Neovascular AMD). Dry AMD
Dry AMD (also called nonexudative AMD) is a broad designation, encompassing all forms of AMD that are not neovascular (wet AMD). This includes early and intermediate forms of AMD, as well as the advanced form of dry AMD known as geographic atrophy. Dry AMD patients tend to have minimal symptoms in the earlier stages; visual function loss occurs more often if the condition advances to geographic atrophy. Dry AMD accounts for 80–90% of cases and tends to progress slowly. In 10–20% of people, dry AMD progresses to the wet type. Geographic atrophy
Geographic atrophy (also called atrophic AMD) is an advanced form of AMD in which progressive and irreversible loss of retinal cells leads to a loss of visual function. There are multiple layers that make up the retina, and in geographic atrophy, there are three specific layers that undergo atrophy: the choriocapillaris, retinal pigment epithelium, and the overlying photoreceptors. The three layers that undergo atrophy in geographic atrophy are all adjacent to each other.
Combined liver-kidney transplantation has been attempted in patients with aHUS, although this high-risk procedure has a mortality rate approaching 50%.Prior to availability and usage of the treatments,  quality of life was very poor for patients with aHUS; burdened with fatigue, renal complications, hypertension, neurological impairment, gastrointestinal distress, clotting at the site of venous access, and in worst cases, death. PE/PI is also reported to be associated with significant safety risks and is highly disruptive to patients lives due to the requirements for extensive vascular access and frequent administration.Since the approval of eculizumab (Soliris) the prognosis for aHUS patients has improved greatly. Risk of relapse is present after discontinuation of eculizumab treatment and close monitoring is required. Epidemiology
aHUS can be inherited or acquired, and does not appear to vary by race, gender, or geographic area. As expected with an ultra-rare disease, data on the prevalence of aHUS are extremely limited. A pediatric prevalence of 3.3 cases per million population is documented in one publication of a European hemolytic uremic syndrome (HUS) registry involving 167 pediatric patients. Society and culture
Naming
Atypical hemolytic uremic syndrome (aHUS) has also been referred to as diarrhea-negative hemolytic-uremic syndrome (D− HUS). : 2170

Research directions
Patient advocacy groups have been helping to determine research priorities. References


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