NEPHRITIS OF INFANCY The course of nephritis in infancy is frequently not attended by any conspicuous symptoms, and it may be only by the examination of the urine, which is often neglected in these little patients Imeause of a fancied difficulty in obtaining it, that the damage to the kidneys is dis covenal. This fancied difficulty and the neglect of urinary examination is responsible for the fact that the investigation of the etiology, clinical course and pathology of infantile nephritis is still so ineagre. Acute nephritis is the most common form, but transition into the more chronic types is also seen. It is of importance in diagnosis to remember that it is not enough to examine the urine for albumin, but always to examine the sediment under the microscope, since in no small proportion of the cases renal casts will be found even where there is no albumin present. And it is certainly true that even a microscopic examination may not prove the absence of disease in the kidneys, because postonortem dis sections have demonstrated serious alterations both in the parenchyma and the interstitial tissue of the kidneys, when during life there had been no sign of pathological changes in the urine. We are especially indebted to Cassel for having pointed out these facts in infancy.
1. Of Gastro-intestinal Origin Kjelberg in 1S'70, in examining 143 cases of "intestinal catarrh" found albumin, casts, and round cells in the urine in 40.S3 per cent. His statements have since been fully confirmed and more carefully analyzed by many writers, amongst whom are Baginsky, Bernhard and Felsenthal. Czerny and Moser, Epstein, Heubner, Hirschsprung, Hoffsten, Parrot, and IViderhofer. Sinunonds was the only one who believed that the cause of the renal trouble was not the "gastro-intes tinal catarrh" per se, but the suppuration of the renal pelvis which often appears as a complication of the catarrh. Czerny and Moser formerly considered that the uranalysis was the most important clinical expedient to distinguish a gastro-enteritis from a simple dyspepsia, since it was then believed that the latter never led to alburninuria or other patho logical changes in the urine.
11le know to-day, however, that any disease of the gastro-intestinal tract. whether attended by fever or not, even a simple dyspepsia, may in infancy lead to albuminuria, whose presence alone, it is true, does not necessarily mean a pathological change in the renal structure. This opinion is shared by Czerny and Keller, who emphasize the fact that even the most insignificant dyspepsia in babies a few- weeks old and nursed at the breast, may be attended by decided albuminuria.
Among the gastro-intestinal diseases the intestinal catarrh and enteritis of Widerhofer's classification seem to be the principal causes of renal disease. Epstein considers that alburninuria is the most important symptom of cholera infantum. According to him it appears within 2-1-1S hours after the onset of the diarrhera, increases with the diminution in Hie amount of the urine which is peculiar to the disease, and attains its highest point at. the acme of the affection.
Symptomatology.—During the acute stages the symptoms of renal disorder are obscured by those of the diarrhreal disease, and the former are only diseovered by the result of a uranalysis. The urine may contain more or less albumin, casts, renal epithelial», and red anti white blood corpuscles. It is only in severe cases that the urine appears red to mere inspection. If death occurs (luring the matte stage of the gastro intestinal disorder with symptoms referrol to the 11(1,,,,US system, convulsions or coma, it may be impossible to say whether or not these symptoms were uraunic. The hydrocephaloid state (Witlerhoferl, and the serious typhoid condition which may appear after the subsi dence of the acute paroxysm, are probably of urattnic origin„just as is the case in the cholera of adults, but it must be admitted that this is not always true of the typhoid symptoms.