16 Vide a case published by Mr. Hinton in the "Brit. Med. Journ." of August 4th, 1860, p. 603, and one by Mr. Sympson in the same Journal of the 7th February, 1863, p. 139.
In fact, jaundice only appears as a complication of gall-stones when they chance to block up the common duct, and thereby prevent the bile entering the intestinal canal. Hence, also, the reason why jaundice, as a result of gall-stones, is more frequently transient than permanent. If it chances to become permanent, it sooner or later leads to a fatal termination—usually within eighteen months after complete obstruction. Lastly, it may be mentioned that, although gall-stones are liable to form in almost every constitution, yet it is generally considered that they are most frequent in persons of the tubercular, cancerous, and gouty diathesis, either hereditary or acquired.
There are other substances besides gall-stones which, by their accidental presence in the bile-ducts, may give rise to jaundice. Thus, for example, foreign bodies, such as cherry-stones, have found their way from the intestine into the bile-duct, and given rise to jaundice. Intestinal worms have been observed to do the same thing, and recently an interesting case of jaundice, occurring in a girl aged 16, who died after a few weeks' illness, has been reported, which resulted from the presence of hydatids in the ductus hepaticus, and ductus communis choledochus.17 Hydatids of the liver itself seldom give rise to jaundice, their position being usually such as not to interfere with the biliary function.
17 Dr. Dickinson has reported this case in the Pathological Society's "Transactions," p. 104, vol. xiii. 1862.
There are still other cases where we find transient jaundice arising from accidental obstruction of the bile-ducts; but in them, instead of the closure of the ducts resulting from plugging from within, it arises from the application of pressure from without. Thus, for example, transient jaundice is met with as the result of closure of the common bile-duct, by pressure exerted upon it by the pregnant uterus, or by impacted fæces in the transverse colon. Certain permanent abdominal tumours may also lead to the same result, but these will with greater propriety be considered under the next head.
PERMANENT JAUNDICE FROM OBSTRUCTION.
In order to give as clear a view as possible of the pathology of permanent jaundice from obstruction, it will be necessary for me to give the history of a case of closure of the outlet of the common bile-duct in consequence of organic disease—such, for example, as cancer of the head of the pancreas. A case of this kind has the further advantage of at the same time furnishing us with a typical example of jaundice arising from the re-absorption of the secreted, but retained bile.
When cancer of the head of the pancreas involves the orifice of the common bile-duct, as the tumour grows, the duct slowly, and gradually becomes impervious to the passage of bile into the intestines, until at length the flow is completely arrested. As this gradual process of occlusion of the outlet goes on, the duct itself becomes more and more distended by the retained bile, till it at length attains an enormous size. The gall-bladder being equally prevented from emptying itself, likewise becomes stretched and dilated, until it may at last become not only palpable to the touch, but even apparent to the eye through the abdominal walls. This was the case in the patient whose liver, and occluded ducts are represented in [Plate I].
The distention of the bile-ducts is not limited to those situated external to the liver, but also affects those in the substance of the organ; and to such an extent may this be the case, that, on making a section of a liver that has long had its common duct obstructed, a number of large excavations are observed all over its surface, which excavations are nothing more than the open mouths of the transverse sections of the dilated ducts. Such a state of matters is tolerably well represented in the section of the liver in [Plate I]. Further, the effect of this obstruction to the exit, and consequent accumulation of the biliary secretion, is not confined to the mere distention of the ducts, but causes various changes to occur in the parenchyma of the liver itself. The first of these is an increase in the size of the organ, arising partly from the accumulation of the bile, and partly from the congestion caused by the pressure exerted on the vessels by the distended ducts. In the second place, gradually as the state of matters here described progresses, the parenchyma of the organ becomes itself affected, partly from the direct pressure exercised upon it, and partly from the derangement of its nutrition, produced by the interruption to the hepatic circulation; so that, after a time, the enlarged liver slowly, and by degrees diminishes, until it at length regains its natural size, thereby rendering, at this period of the disease, the diagnosis of the case extremely difficult. This state of matters is not, however, of long duration; for, in consequence of the continued compression of the blood-vessels and parenchyma, the nutrition of the liver is so disordered, as to lead to a gradual shrinking of the entire substance, or, in other words, to a general atrophy of the organ.
It is thus seen how in permanent occlusion of the common gall-duct the liver may be found hypertrophied in the first, of normal dimensions in the second, and atrophied in the third and last stage of the disease.