An imperforate rectum has been known to discharge at the umbilicus, upon the face, under the scapula, upon the penis or the anterior part of the scrotum. Sometimes, though very rarely, a common cloaca has been found, as in fowls, common to the rectum and to the genito-urinary organs; and still more rarely the rectum has opened in abnormal sites upon the perineum and upon the buttocks.
The anus may be entirely absent. The rectum may be entirely absent or it may be incomplete, terminating at various distances from the anus. These malformations of the bowel may be associated with a perfect anus, or with any of its imperforate forms, or with a fecal fistula. In occlusion of the rectum the offending structure is in some cases a hymen-like fold of mucous membrane, which, during straining, can be recognized by the finger as a fluctuating protrusion; while in others it consists of a mass of dense fibrous tissue which extends upward from an inch to an inch and a half: in the former there is always found a normal anus; in the latter there is either no trace of anus or one in a more or less rudimentary state. In those cases where the rectum is entirely absent the intestine terminates either in a cul-de-sac or a fecal fistula; very rarely the rectum is replaced by a fibro-ligamentous cord or band which springs from the colon, and, descending toward the bladder, blends with the connective tissue of the part. In the latter the pelvis is always in an imperfect state of development, being much contracted in its lower diameters, and the anus is absent; and Rokitansky and Curling lay stress upon the non-development of the pelvis as a diagnostic guide in determining the absence of the rectum. The passage of a sound into the bladder or vagina is a procedure of some diagnostic value, as if its point impinges directly against the sacrum it may be presumed that no rectum exists. If the malformation is of such a character that the fecal matter can find no exit, a train of symptoms ensues analogous to those seen in the adult affected with intestinal obstruction: the infant cries and is constantly restless, refuses food, vomits, the abdomen distends, and death speedily ensues. A remarkable exception to this rule was the case mentioned by Bodenhamer of a child with absence of the rectum who was not operated on until three months after birth, and who was apparently in perfect health. At the operation the intestine was found three inches from the surface, and the child made a good recovery.
Although the statistics of this class of malformations are somewhat contradictory and confusing, it is safe to state that more male than female children are so afflicted.
The prognosis in the large majority of these cases is grave, for unless the operator can see or feel the fluctuating protrusion, or can recognize it after a very slight exploratory incision, he is working totally in the dark and in close proximity to the peritoneum. Hemorrhage, peritonitis, pelvic cellulitis, and septicæmia diminish the chances for recovery. Indeed, the majority of these cases are scarcely amenable to surgical treatment.
PRIMARY DISEASES OF THE RECTUM AND ANUS.
Prolapse and Procidentia of Rectum and Anus.
These conditions obtain most frequently at the two extremes of life, infancy and senility, but have a very different causation in each. Prolapse of the bowel may be partial or complete—partial when a portion of the mucous membrane is extruded, and complete when the entire rectum appears outside the anal orifice. A predisposing cause in infants is found in the mobility of the bowel—in the fact that it and the sacrum are much less curved than in the adult, and the abdominal viscera are more voluminous: this, associated with the undeveloped state of the muscular system, causes the weight and strain to act directly and forcibly upon the sphincters, and the extrusion takes place. It is often excited by allowing children to sit for a length of time upon the chamber-vessel. It is frequently caused among children by the presence of vesical calculi, by Oxyuris vermicularis, diarrhoea, constipation, dysentery, polypi, and by the long-continued acts of coughing and crying.
In adults and the aged it may be caused by loss of tone of the anus and rectum in chronic diarrhoea and dysentery, or from the energetic action of drastic cathartics, by urinary calculi, the long-continued use of enemata, chronic cough, diarrhoea alternating with constipation, stricture of the urethra, prostatic hypertrophy, tenesmus due to the presence of polypi, and by the pressure of a pelvic tumor. It may accompany procidentia uteri and hemorrhoids. An incomplete, reducible prolapse consists of two or more overlapping plications of normal-looking mucous membrane, sensitive but painless. In these cases there is provoked a hyperplasia of much-elongated connective tissue in the submucous space which undergoes serous infiltration and causes an oedematous condition of the part. In a complete prolapse the entire rectum—all of its component layers—is protruded through the anus. In a recent case the folds of the gut are well marked, but in one where the bowel has remained in this abnormal condition for some time the submucous tissue becomes charged with inflammatory deposit which effaces the plications and causes the bowel to become pale, hard, dry, and tough; and finally pigmentation occurs and the part assumes somewhat the character of true skin. These vary greatly in size, from the slightest protrusion of mucous membrane to a tumor the size of a melon. Usually they are reduced with ease, but their reappearance is occasioned by the slightest tenesmus.