Crampy pains in the legs and facial paralysis are among the nervous symptoms sometimes present, and the term diabetic neuralgia has been applied to a special form of neuralgia peculiar to this disease. It is characterized by its acuteness, stubbornness, and symmetry. Its favorite seats are the inferior dental nerves and the sciatics. Greisinger referred to the frequency of sciatica in 1859, Braun again in 1868, and others still later; but Worms in 1881 established the close relation between the two conditions and the features described. Most recently (1884), Cornillon[19] collected 22 cases of diabetic neuralgia, and has further elaborated the study. Believing that diabetes affects particularly those persons who have had serious attacks of rheumatism and gout, he is inclined to think the neuralgia as much due to uricæmia as to hyperglycosuria, and that these conditions cause, not neuritis, but transitory lesions in the nerve-centres, but whether in the membranes or gray or white matter is undetermined. [Footnote 19: "Des nevralgies diabétiques," _Revue de Médecine_, 1884, iv. 213-230.] That the phenomena of acetonæmia are those of a toxic agent or agents in the blood derived from the sugar there present is generally conceded, although Sanders and Hamilton,[20] after a study of the clinical histories and the result of autopsies in several cases, are disposed to ascribe diabetic coma to slow carbonic-acid poisoning due to fat embolism of the pulmonary vessels. So far as I know, these conclusions have not been reached by any other observers. R. H. Fitz[21] and Louis Starr[22] have each reported cases of diabetic coma with lipæmia, carefully studied with this point in view, without finding any facts to sustain the carbonic-acid theory. [Footnote 20: _Edinburgh Med. Journal_, July, 1872.] [Footnote 21: "Diabetic Coma; its relations to Acetonæmia and Fat Embolism," _Boston Medical and Surgical Journal_, vol. cvi. p. 24, Feb. 10, 1881.] [Footnote 22: "Lipæmia and Fat Embolism in Diabetes Mellitus," _New York Medical Record_, vol. xvii., 1880, p. 477.] Alterations in the Blood.--The blood of diabetics is variously charged with sugar, which may be in such quantity as to impart a viscidity and higher specific gravity to the plasma, which has reached 1033, the normal being 1028. On the other hand, analyses have sometimes failed to discover sugar in the blood after death, the result, probably, of the tendency of the sugar to rapid disintegration. Alcohol and acetone, or {207} acetone-producing substance (aceto-acetic acid), are occasionally present as the products of such decomposition, to which are ascribed the symptoms of acetonæmia already discussed.