TherapentiCS. — RENAL DISORDERS.— Methylene-blue being eliminated by the urine, Achard and Castaigne recently conceived the idea of using this property to determine renal permeability when disease of the kidney is suspected. -When the kidneys were normal methylene-blue proved to be eliminated rapidly, com municating to the urine a distinctive color: in diseased conditions, however, elimination was retarded. Considerable a.dema did not hinder the absorption of the methylene-blue, and its consequent appearance in the urine. The authors were able to trace, by defective elimina tion, the progress of lesions, which were at the same time indicated by the in crease in clinical symptoms.
A dose of 1 grains of methylene-blue colored the urine until tile third day.
After a dose of '/, grain the urine was still colored on tile following day, and even to a slight degree on the day after. The dose being gradually lessened, it WaS found that after 73 grain the urine was distinctly colored, and had not entirely regained its normal appearance the next day. Constantin Paul (La Sem. Med., Dec. 30, '91).
Fifty observations in which use of methylene-blue in the diagnosis of renal permeability was used.
In 22 the blue was eliminated in a nor mal fashion. and autopsies in 5 of these showed that the kidneys were sound notably in one case of phthisis, and an other of pneumonia in which albumi nuria was present during life. On 28 occasions the perrneability of the blue was faulty, and in 13 of these alterations in the kidneys were discovered after death. The lesions found were suppura tive pyelonephritis in 3, considerable renal atrophy in 1, infarcts in a solitary kidney in 1, and cystic kidneys in an other, in whom albuminuria was absent during life.
In limited lesions of the kidney—tuber cular, for instance—in which the rest of the organs was healthy, the permeability was normal.
In several permeability varied. Thus, phthisical patient in whom it had been normal, suddenly showed delay of elimi nation, while cedema, albuminuria, and licernaturia made their appearance.
On tbe contrary, in acute affections permeability was defective only through out the illness, and became normal on recovery.
Some cases seemed to show that excess of permeability was as much a sign of disease as insufficiency.
The methylene-blue is given by intra muscular injections of 1 cubic centimetre of a 1 to 20 solution.
In some eases the blue is slowly elimi nated. but the urine from the first gives a green coloration when warmed with acetic acid.
This is due to a colorless chromogen insoluble in chloroform, which latter pre cipitates it from methylene-blue.
In nine patients there was no delay in elimination of either chromogen or blue.
In eight others elimination of both was delayed; these had symptoms of renal disease, and the diagnosis of renal disease was verified often on post-mortem exami nation.
Often in similar cases the chromogen was eliminated before tne blue, thus showing that the fornier is more diffusible and passes more easily through diseased kidneys than the latter.
In 11 there was only delayed elimina tion of blue, while the chromogen passed within the first hour after adrninistra tion.
There were many clinical symptoms of renal disease in these, and on two occa sions post-mortem examinations revealed advanced degenerative changes in the renal epithelium.
Delayed elimination of the blue alone occurs in some cases of renal disease, but it is not yet possible to state that renal changes are the sole cause of this. It is important, however, to test for chromo gen by heat and acetic acid in patients who eliminate blue slowly, as by compar ing the rate at which both chromogen and blue are eliminated one may be able to arrive at useful aids to diagnosis. Achard and Castaigne (La Sem. Med., June 23, '97).
The usefulness of methylene-blue will be greatest as a means of testing the per meability of the kidney and i» the treat ment of the early stages of chronic Bright's disease, while it oug,lit to be in valuable in those cases of renal inade quacy occurring as concomitants of acute infectious and contagious disease, where the probable selective effect of the drug, upon the functional epithelium of the tubules and glomeruli, stimulating the excretory function, will prevent the ac cumulation of toxic material in the blood. II. A. Tomlinson (Northwestern Lancet, xviii, p. 61, '98).
Renal permeability to methylene-blue only refers to the drug itself, and has nn other significance whatever. Nesti (.A.n nales des Mal. des Organcs Jan., '99).
Methylene has been used with success in renal disorders of various types, in cluding cases of interstitial nephritis.