Section 2. the Intestines.

=Malformations.= The intestine is sometimes defective in some part of its course, most usually near its lower extremity, and generally accompanied with an imperforate condition of the anus, (atresia ani.) This latter may be of various degrees, consisting sometimes in a simple closure of the anus by a continuation of the integument over it; in other cases the rectum terminates in a blind pouch at a greater or less distance from the anus.

Sometimes the intestine is unusually short, without any distinction as to size between the large and small intestines.

It may terminate at the umbilicus, or in a cloaca common to it and the genito-urinary organs.

Finally, it may consist of several detached cœcal portions.

Andral notes the following malformations:—A single straight canal from the termination of the œsophagus to the commencement of the rectum; a double duodenum; two colons; an unusually large, and at same time, double appendix vermiformis.

Diverticula are not unfrequent. They are cœcal appendages, resembling the finger of a glove, one or more in number, varying in length from a few lines to several inches, and giving off at various points. Like the appendix vermiformis, they may become a source of danger by affording a lodgement for indigestible matters.

In very rare instances the position of the intestines has been found completely transposed, with a corresponding transposition of all the abdominal viscera, or of only one organ.

=Inflammation.= Vascular injection by itself cannot be taken as a decisive proof of the existence of inflammation. Obstruction to the free return of blood by the veins, during life, and the gravitation of blood to the most dependent parts, after death, especially after fevers, can and do produce this very marked injection. In general, however, the smaller and more isolated the patch of injection is, the more likely it is to be inflammatory in its origin.

Catarrhal inflammation may be either acute or chronic, and may either attack the mucous membrane uniformly, or be developed mainly in the villi and follicles.

In the acute form: “There is more or less intense redness and injection of the mucous membrane, affecting its entire surface, or appearing as punctiform reddening from affection of the villi, or as a vascular halo surrounding the follicles; relaxation of the tissue, and intumescence of the mucous membrane, equally affecting the entire surface, or only the villi and follicles; opacity of the mucous membrane and its epithelium, from infiltration of the former and softening of the latter; friability and softening of the mucous membrane. The submucous cellular tissue is injected, relaxed and infiltrated with a watery opaque fluid; the secretion is at first copious and serous; as the affection increases in intensity it becomes opaque, viscid and puriform.”

In the chronic form, besides the above signs, we have also a dark, rusty, livid discoloration, sometimes pervading the entire mucous membrane; the mucous membrane and its follicles are swollen, the tissue has become more dense, and the surface covered with an opaque, grayish-white, or puriform mucus. Polypoid excrescences are sometimes found upon the mucous membrane.

Both the large and the small intestines may be affected by catarrhal inflammation, although the chronic form seems to occur more frequently in the large.

The muscular coat of the intestines is also sometimes the seat of inflammation, rarely if ever, however, as a primary disease, but by extension from the serous covering or mucous lining.

Croupous Inflammation. The mucous membrane is also subject to a chronic or sub-acute form of inflammation resulting in the production of an exudation much resembling that of croup. Sometimes it forms in a layer of some thickness, pretty uniformly over the surface, or appearing in the stools as tubular casts of the intestines; sometimes it is very thin, or consists of mere shreds. The anatomical changes observed will be similar to those just noticed.

Perityphlitis is an inflammation of the loose areolar tissue around the cœcum, occurring primarily or in consequence of typhlitis. If not checked, it ends in the formation of abscess in the right iliac fossa, which may discharge either into the neighboring viscera, or externally through the abdominal walls, mostly near Poupart’s ligament.

Peripractitis is an inflammation of the areolar tissue around the rectum. The resulting abscess discharges either externally, back of the anus, or in the perineal region, or internally into the rectum, or more rarely into the bladder, the vagina, the uterus, or into some other part of the intestines. Fistula in ano, frequently originates in this manner.

=Ulceration.= Ulceration may occur as the result of inflammations both catarrhal and croupous, and whether commencing in the mucous or the muscular layer, the ulcers may perforate the intestinal walls and give rise to an escape of the contents; or the ulcers may cicatrize with the formation of the usual fibroid tissue, which, by subsequent contraction, may give rise to puckering or obstruction.

In follicular ulceration of the colon, after lientery or tedious diarrhœa, the follicles are at first tumefied, and project as smaller or larger, round, conical nodules on the internal surface of the intestine, surrounded by a dark red vascular halo. Ulceration takes place in their interior; an abscess with red, spongy walls appears; the follicle is eaten away, and an ulcer of the size of a pea or lentil is formed. The mucous membrane is extensively destroyed, and with great rapidity. The disease is always confined to the colon, but when it runs a very rapid course, it may be accompanied with catarrhal inflammation of the small intestines.

Typhus ulcers. In continued fevers where the disease especially attacks the intestines, we find an ulceration of Peyer’s patches and the solitary glands, which is called typhus ulceration by Rokitansky, and is thus described by him:—“After a preceding hyperæmia around the solitary follicles, and in and around Peyer’s patches, there is an enlargement of the glandular structures, followed by a softening and breaking down of the glandular mass. The cavity remaining on the mucous membrane after the discharge of this mass constitutes the typhus ulcer. Its form is elliptical, if a large patch has been destroyed; round, if a smaller patch or a solitary gland has been destroyed. Partial destruction of a patch will produce an ulcer of irregular shape. The size varies also, according to the amount of ulceration.”

The margin of the ulcer is invariably formed by a well defined fringe of mucous membrane, which is a line or more wide, detached, freely movable, of a bluish-red, and subsequently of a slaty or blackish-blue color. The base of the ulcer is formed by a delicate layer of submucous tissue, which covers the muscular coat. The lower third of the small intestine is most liable to be involved in the ulcerative process, the number and size of the ulcers increasing as they advance toward the ileo-cœcal valve.

Dysentery may also produce extensive ulceration of the colon, with considerable loss of substance. This loss may be repaired by cicatrization. In some cases, the cicatrix tissue, condensed into fibrous bands, forms projections into the cavity of the intestine, and not unfrequently encroaches upon its calibre in the shape of valvular or annular folds, giving rise to stricture of the colon.

=Dilatation.= Disease of the nervous centres, inflammation of its serous tissue, or simple atony of the muscular fibres, may be the cause of inaction of the intestine and consequent distension. Stricture will also produce distension above itself, by an accumulation of the contents of the intestine. In these latter cases, the dilatation is often enormous.

=Contraction= of the intestines may occur throughout a considerable extent, or in a very small part.

In the former case, it results from the canal having been for some time empty, and is most likely to occur below a stricture. It can hardly be considered in itself a morbid condition.

The second kind of contraction or constriction, is generally morbid, and may result either from external pressure by tumor or otherwise, or from a disease of the tissue itself. The cicatrices of ulcers which have assumed an annular shape, are the most frequent causes of stricture originating in the intestine itself.

=Displacements.= The most common of these constitute the various forms of hernia.

1. Inguinal Hernia. Here the intestines escape by the inguinal canal, and it is Scrotal in man, when they descend into the scrotum, and Pudendal or Vulvar in woman, when into the labia majora.

2. Crural or Femoral Hernia; when the intestines escape by the crural canal.

3. Hernia at the Foramen Ovalis; when the viscera escape through the opening which gives passage to the obturator vessels.

4. Ischiatic or Sciatic Hernia; when it takes place through the sacro-sciatic notch.

5. Umbilical Hernia; when it occurs at or near the umbilicus.

6. Epigastric Hernia; occurring through the linea alba, above the umbilicus.

7. Hypogastric Hernia; when it occurs through the linea alba, below the umbilicus.

8. Perineal Hernia; when it occurs through the levatorani and appears at the perineum.

9. Vaginal Hernia; occurring through the parietes of the vagina.

10. Diaphragmatic Hernia; when it passes through the diaphragm.

A more detailed description of hernia belongs to works on surgery.

A hernia, if not reducible, may, by becoming strangulated, give rise to constipation, hiccough, vomiting, and all the signs of violent inflammation. Gangrene supervenes, with alteration of the features, small pulse, cold extremities, and death.

=Incarceration=, is a form of mechanical obstruction of the bowels, differing from hernia, in there being no escape of the intestine from the abdominal cavity, as in the latter case. It may arise in various ways, but the most frequent form is that in which a portion of intestine becomes constricted by means of fibrous bands which have formed as a result of peritoneal inflammation. Passing from one portion of the intestines to another, or from the intestines to the abdominal walls, a loop of bowel may slip beneath or between these bands, and become so compressed, as to interfere with the passage of the contents, and result in great dilatation of the gut above the point of stricture. Complete strangulation may finally result, and the patient die with symptoms of mechanical obstruction.

Another, but less frequent form of incarceration, is where a portion of intestine slips through the foramen of Winslow, or through a congenital opening in the mesentery, as in the following

CASE:—Death from Strangulation of the Bowel, from becoming Incarcerated in an opening in the omentum.

Mary H——, aged five years, was taken suddenly with great pain in the bowels at 2 o’clock A. M., having retired the night before in perfect health. Vomiting soon set in, accompanied with great thirst, and the whole body became bathed in a profuse cold perspiration. The severe pain continued, and the vomited matter became stercoraceous. I saw the case at 10 o’clock A. M., and then found the child in a moribund condition. The breathing was rapid; pulse very small and frequent; skin pale, damp and cold; eyes sunken and nose pinched. Rapidly sinking, she died at 12 M.

Autopsy twenty-four hours after death. Upon opening the abdominal cavity, a large portion of the intestines was found of a dark purple or black color, while the remainder was perfectly natural in color. Upon lifting the bowels and exposing the mesentery, there was found an opening in the latter, of sufficient size to receive the thumb, and through which a large portion of the small intestines had become crowded, producing such a twist in the border of the mesentery as to have produced complete strangulation of the bowel, which had rapidly passed into a gangrenous state, resulting in violent shock and death in less than twelve hours.

The opening was situated at about one inch from the intestinal border of the mesentery, and was plainly congenital in its origin, as indicated by its smooth and rounded edges.

Another form of obstruction is sometimes found, and known as

=Volvulus=, in which a loop of bowel, generally of the small intestines, becomes twisted upon itself, the constriction at the base of the loop, finally resulting in complete closure.

=Intussusception=, or invagination of the bowels, consists in the slipping of a portion of intestine into itself, and generally from above downwards. Either the large or small intestines may be found in this condition, but it is much more frequent in the lower portion of the small bowels. From a few inches to a foot or more of the bowel may thus become slipped into itself, and it may be found at more than one point.

From the constriction which must necessarily attend such a displacement, congestion with hæmorrhage may result, or peritoneal inflammation, gangrene, and death, with symptoms of mechanical obstruction. In some rare cases, the inner or invaginated portion of the bowel sloughs off, adhesion takes place at the point of commencement of the intussusception, and the patient recovers.

This form of displacement may be found in both children and adults, where the appearance of the parts are such as to render it apparent that it had not been a source of trouble during life.

=Rupture= of the intestines may result from severe injury by blows, or from a crushing force applied to the abdominal walls.

Penetrating wounds of the bowels may be followed by escape of the intestinal contents into the peritoneal cavity, acute peritonitis, and death. If the bowel be empty at the time, adhesions may form between the adjoining parts, the wound thus closed, and recovery follow.

Prolapsus of the rectum consists in a protrusion of the mucous membrane or entire walls from the anus. The only post-mortem change that may be detected is a relaxed condition of the coats of the bowel, with congestion of the mucous membrane.

=Diseases of the Anus.= These include ulcer and fissure of the anus, fistula in ano, and hæmorrhoids.

Ulcer, and fissure of the anus, usually accompany each other, though either may exist alone. The ulcer, when present, is found just within the anus, while the fissure extends from this across the edge of the sphincter. While these affections are trifling in their post-mortem appearance, they are of great importance from the local trouble and constitutional irritation which they may produce during life.

Fistula in ano, consists in the presence of a false passage along side the rectum, usually the result of a small abscess in the ischio-rectal fossa. It is said to be complete when it opens at one end into the bowel, and at the other through the integument near the anus; and incomplete, when it has but one opening, whether that be on the surface or in the rectum.

Hæmorrhoids will be noticed under the head of

Morbid Growths.

=Cancer=, in its various forms, may be found in connection with the intestines, where it is usually primary in its origin. The scirrhus form is more frequently met with in the rectum, and is likely to involve the whole circumference of the passage. From the tendency which this form has to contract the parts, stricture of the rectum is likely to result, which may become a source of great suffering, and finally of death. Other forms of cancer may be found in any portion of the intestines; the colon and rectum, however, being their more frequent location.

Cancer of the intestines is very liable to extend to the surrounding tissues and organs, and in many cases, perforations of the bowel, or fistulous communications between the rectum and bladder in the male, or uterus or vagina in the female, may result.

=Tubercles=, generally of the miliary form, may be found within the coats of the intestines, principally confined to the peritoneal covering however. They may occasionally be found in the mucous coat, and in the walls of follicular ulcers of that membrane.

=Tumors= of various kinds may be found in connection with the intestine.

Fatty tumors may originate within the mucous membrane, and project as polypoid growths into the cavity of the bowel; or they may commence in the appendices epiploicæ, and degenerate into a cystic tumor with fluid contents, or become infiltrated with calcareous matter; or the pedicle may become atrophied and the tumor detached, and found free in the peritoneal cavity.

Adenoid tumors may result from hypertrophy of the several forms of glands of the intestines, and appear as soft, rounded, and perhaps pedunculated tumors, which are liable to become ulcerated.

Fibroid tumors of small size and polypoid form, may be found in any part of the intestines, and are generally considered as a result of chronic inflammation.

Hæmorrhoids or piles, consist in a dilatation of the veins of the lower portion of the rectum, with a thickening of their walls, and increase of surrounding fibrous tissue. They may be internal or external. The contained blood may coagulate forming a thrombus. The walls may rupture, giving rise to hæmorrhages, or become inflamed and suppurate.

Abnormal contents. The normal contents of the bowels may be found mixed with the various products of inflammation, including mucus, serum, blood and pus.

Biliary calculi and foreign bodies of various kinds, may be found, which may have produced no effects, or they may have served as nuclei, around which the salts of lime, bile, mucus, fæcal matter, etc., may have accumulated, producing intestinal concretions.

=Parasites.= The intestinal canal is infested by several forms of entozoa, among which may be found the following:

Ascaris lumbricoides; the common round worm, six to ten inches in length. It may be single or in large numbers.

Oxyuris vermicularis; a small white worm, measuring from two to four lines in length, and found only in the large intestines, and mainly in the lower part of the rectum, where they may be present in large numbers.

Trichina spiralis. This parasite is found in the small intestine, and only in its adult form. It measures from less than a line, to two lines in length. The embryos penetrate the walls of the intestine, and finally locate in the muscles, where they remain encapsulated. If a portion of this muscle is eaten by another animal, the larvæ again become active, and acquiring the mature sexual form, reproduce, the young embryos again migrating to the muscles.

Tricocephalus dispar. Found only in the head of the colon, and measures one and a-half to two inches in length; neck long, and body of male covered with wart-like appendages on one side.

Distoma lanceolatum. Flat, lancet-shaped, and transparent, a-half inch long, one-quarter wide. Rarely found in upper portion of small intestines, natural habitat appearing to be in the bile passages.

Of tapeworms, the following varieties may be found:

Tænia solium. Head about the size of a pin-head, and furnished with sucking disk and double row of hooks; neck long and narrow; body flat and jointed, each segment about a-half inch in length; body may be from ten to fifty or more feet in length.

Tænia mediocanellata. Head truncated and destitute of hooks; body jointed and of great length.

Tænia flavopuncta. Very rare. Yellow spot at the middle of each joint.

Bothriocephalus latus, (broad tapeworm.) Head long, unarmed; neck inconspicuous; body composed of about two thousand joints; mature joints broader than long.