The largest number of cases has been observed in the United States—over thirty in number. It was at first thought that this was an exclusively Jewish disease because most of the cases at first reported were between Russian and Polish Jews; but recently there have been reported cases occurring in non-Jewish children. The chief characteristics of the disease are progressive mental and physical enfeeblement; weakness and paralysis of all the extremities; and marasmus, associated with symmetrical changes in the macula lutea. On investigation of the reported cases, they found that neither consanguinity nor syphilitic, alcoholic, or nervous antecedents in the family history are factors in the etiology of the disease. No preventive measures have as yet been discovered, and no treatment has been of benefit, all the cases having terminated fatally. Jewish immigration to the United States peaked in the period 1880–1924, with the immigrants arriving from Russia and countries in Eastern Europe; this was also a period of nativism (hostility to immigrants) in the United States. Opponents of immigration often questioned whether immigrants from southern and eastern Europe could be assimilated into American society. Reports of Tay–Sachs disease contributed to a perception among nativists that Jews were an inferior race.In 1969, Shintaro Okada and John S. OBrien showed that Tay–Sachs disease was caused by an enzyme defect; they also proved that Tay–Sachs patients could be diagnosed by an assay of hexosaminidase A activity.
18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT)has become a widely used imaging tool in patients with suspected Large Vessel Vasculitis, due to the enhanced glucose metabolism of inflamed vessel walls. The combined evaluation of the intensity and the extension of FDG vessel uptake at diagnosis can predict the clinical course of the disease, separating patients with favourable or complicated progress. Acute onset of vasculitis-like symptoms in small children or babies may instead be the life-threatening purpura fulminans, usually associated with severe infection.In this table: ANA = antinuclear antibodies, CRP = C-reactive protein, ESR = erythrocyte sedimentation rate, dsDNA = double-stranded DNA, ENA = extractable nuclear antigens, RNP = ribonucleoproteins; VDRL = Venereal Disease Research Laboratory

Treatment
Treatments are generally directed toward stopping the inflammation and suppressing the immune system. Typically, corticosteroids such as prednisone are used. Additionally, other immune suppression medications, such as cyclophosphamide and others, are considered. In case of an infection, antimicrobial agents including cephalexin may be prescribed. Affected organs (such as the heart or lungs) may require specific medical treatment intended to improve their function during the active phase of the disease. References


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