In regard to the second point, we find that Jchle's experiments themselves and the test cases of other authors have proved that experi mental lordosis leads to albuminuria only in a certain percentage of cases. There is no reason whatever to suppose that in the negative cases the spinal cord should offer any particular resistance to the production of an effective lordosis, if we confine ourselves to children and exclude adults. I have seen cases of most pronounced lordosis, in dystrophy, for instance, in which the urine did not contain the slightest trace of albumin. The dictum that the kidney reacts with the regularity of a physical experiment to the position of the body in lordosis, is therefore far from being a demonstrated fact.
The last point concerns the question whether Jehle's assumption is correct that renal stasis by compression of the inferior vena cava explains the pathogenesis of orthotic albuminuria. The fact of its being possible to obtain by pressure on the vena cava through the abdominal walls a urinary picture similar to that in lordotic alburninuria is of course no proof for the identity of both forms of albuminous excretion. In my opinion it is exceedingly difficult to believe that lordosis of the lumbar spine causes compression of the vena cava, as the latter is not a rigid system incapable of evading a pressure. If the pathogenesis of orthotic and lordotic albuminuria were identical and the vena CaVa were com pressed each time upon arising, a short time would suffice to form a collateral circulation which would cause the affection to disappear. Indeed, Jehie himself refers to such a collateral circulation, but only to explain by it the daily vacillations of orthotic albuminuria. He fails to consider that the daily demands made upon it 1, ould in a. short time develop it to such an extent as to cause the albumin to disappear, which however is not the case. Pfaundler, too, disagrees with Jehle in so far as a causal connection between lordosis and renal insufficiency is concerned. In vain he looks for a plausible explanation in what way the topographic and mechanical conditions can cause compression, tearing, kinking, or any other impairment of the renal blood. Furthermore. Pfaundler points out that Jehle's mechanical theory is at variance with experi ments in which alimminuria appeared in an orthotic patient who was immovably fixed and gradually raised to a certain degree from the horizontal position. Increased pressure in the renal veins cloes not
cause albuminuria.
These objections are not intended to detract from the great impor tance of Jehle's experiments. They are intended to sound a warning not to prematurely derive therefrom the identity of all forms of albu minuria, even the "physiological" form, which in my opinion is still shrouded in complete mystery. Thus, Winternitz unquestionably goes too far in trying to explain the occasional occurrence of albuminous excretion in swimmers, as follows: "Unpracticed swimmers endeavor to keep the head above the water as much as possible, which would of necessity bend the body backward and cause a lordotic curvature of the lumbar spine, especially of the uppermost vertebra.. This would cause a mechanical condition which Jehlc considers necessary for the induction of albuminuria. Sponging, douching, etc., do not produce albuminuria because these procedures do not involve a lordotic curvature of the lumbar spine. In fact, when using the bath tub, the upper part of the body is bent forward, and that is perhaps the reason why even after the coldest and longest tub baths traces of albumin are found only quite exceptionally." In my opinion it would be disastrous for the investigation of the albuminuria question if a uniform opinion were adopted before the foundations upon which the affection rests have been established. All we know is that orthotic albuminuria is a special and peculiar form of a long-lasting renal secretion of albumin which does not depend upon a tissue affection of the renal substance, but is bound up with a certain period of organic development. In all probability it is a functional disturbance the vasomotor region.
diagnosis of physiological albuminuria is not particularly difficult, but cannot sometimes be made with absolute certainty, especially if the case has only been observed for a short time." This statement of von Leube may be adopted for the diagnosis of orthotic albumininia likewise. It is not an instantaneous diagnosis and requires the exclusion of a group of affections with which it has the general condi tions in common which have been above described. These, according to von Leube, are terminating nephritis, beginning nephritis, insidious interstitial nephritis, albuminuria of puberty.