The term parametritis, introduced into use by Virchow, is, properly speaking, limited to inflammation of the connective tissue immediately adjacent to the uterus, the older one of pelvic cellulitis furnishing a more comprehensive designation for cases where, as a consequence of a progressive advance from the point of departure in the genital canal, the remoter regions have likewise been invaded. Connective-tissue inflammation presents, as the first essential characteristic, an acute oedema, the fluid which fills the gaps and interspaces consisting of transuded serum rendered opaque by the presence of pus-cells or possessing a gelatinous character. In the mild, uncomplicated cases the oedema disappears rapidly. Where the cell-collections are of moderate extent the entire process may vanish without leaving a trace of its existence. If the cell-elements, on the other hand, are present in great abundance, they, as a rule, first undergo fatty degeneration, and, after the absorption of the fluid portion, form a hard tumor composed of a fine granular detritus, which under favorable circumstances likewise after a few weeks becomes absorbed. In rare cases abscess-formation in the tumor results.
In the cellulitis resulting from septic infection, especially in cases complicated by diphtheritis, the tissues seem as if soaked with dirty serum, and contain scattered yellowish deposits, which soon present, even to the naked eye, the appearance of pus-collections. This sero-purulent oedema is always associated with lymphangitis, the lymphatic vessels possessing varicose dilatations and beaded arrangements similar to those already described in the uterine tissue. The foregoing changes are most distinct in the firm connective tissue adjacent to the uterus and at the hilum of the ovary, while they are less clearly traced in the looser structure of the broad ligament (Spiegelberg).
In favorable cases the inflammation is circumscribed, or at least is limited, by the nearest lymphatic glands. In cases of intense infection it spreads rapidly, and justifies the title bestowed upon it by Virchow of parametritic malignant erysipelas.
PELVIC AND DIFFUSED PERITONITIS.—Inflammation of the pelvic peritoneum may result from severe attacks of catarrhal endometritis, the inflammatory process either traversing the uterine tissue or passing through the Fallopian tubes to the adjacent serous membrane; or it may proceed, secondarily, from the stretching and irritation occasioned by an associated parametritis.
As a rule, pelvic peritonitis is not attended with much exudation. The latter is situated upon the folds of the peritoneum limiting the cul-de-sac of Douglas, upon the ovaries, and upon the broad ligaments. In favorable cases it consists of fibrinous flakes and fluid pus. If the latter is abundant, it may become encysted by the formation of adhesions between the pelvic organs.
General peritonitis may result from the extension of a pelvic peritonitis, or from the transport of poison through the lymphatics into the peritoneal sac. In the first case the entire peritoneum is injected, and the contents of the abdominal cavity are loosely bound together by pseudo-membranes, composed of pus and coagulated fibrine. The intestines are at the same time distended and the diaphragm is pushed upward. In the so-called peritonitis lymphatica the inflammatory symptoms are at the outset lacking. The abdominal cavity is found filled with a thin, stinking, greenish or brownish fluid composed of serum and micrococci. The intestines are lax and oedematous, and the muscular structures are paralyzed, with resulting tympanitic distension. The peritoneal covering of the intestines is devoid of lustre, and covered with injected patches, or is stained of a dark-brown color. Death often ensues before the occurrence of exudation.
Septic forms of pelvic inflammation are often associated with oöphoritis, the dilated lymphatics either extending to the substance of the ovaries, where they may lead to the production of small abscesses, or, as a result of blood-dissolution, the organs become soft, pulpy, and infiltrated with discolored serum, and present hemorrhagic spots distributed over the surface.
PHLEBITIS AND PHLEBO-THROMBOSIS.—The formation of thrombi in the uterine and pelvic veins is sufficiently common during the puerperal period. The coagulation may result from compression or from enfeeblement of the circulation. A predisposition to its occurrence is created by relaxation of the uterine tissue. A normal thrombus is in itself harmless. In time it becomes organized, and the occluded vessel is converted into a connective-tissue cord, or a channel may form through it which permits the passage of the blood-stream. When, however, pus or septic matters obtain access to a thrombus, it undergoes rapid disintegration, and the particles get swept away into the circulation until arrested in the ramifications of the pulmonary artery. Wherever these poisoned emboli happen to lodge inflammation is set up in the adjacent tissues, and abscesses result (pyæmia multiplex). Sometimes countless collections of pus may form in the lungs. Less commonly abscesses are found in the liver or spleen, originating either from emboli which have already made the pulmonary circuit or from thrombi in the pulmonary veins.
Inflammation of the veins (phlebitis) sometimes occurs when the vessels have to traverse tissues in or near the uterus infiltrated with purulent or septic materials. The endothelium then undergoes proliferation, and thrombosis is produced. Phlebitic thrombi do not necessarily break down, and may in that case act as a barrier to the progression of septic germs into the circulation (Spiegelberg). As a rule, however, under the influence of inflammation and infection, they become converted into puriform masses.
The thrombi grow by accretion in the direction of the heart. They may extend from the uterus through the internal spermatic, or through the hypogastric and common iliac veins, to the vena cava. Sometimes the thrombus may be traced back to the placental site.