PY1EMIA (Neo-Lat., from Gk. rtiov, pyon, pus + at,ua, hainm, blood). This term and that used to designate the closely allied condition, septica-Inia, originated before the idea of bac teria as the etiological factor in the diseases, was developed. They have become so fixed in medic-al nomenclature, however, that they arc still re tained. 1-fore the discovery of bacteria as the exciting ea use, it was the general belief that septicaemia was a condition caused by the pres ence in the blood of substances undergoing putre faction, while pyamia was due to the presence of pus, itself in blood channels. In the light of our present bacteriological knowledge, we reeognize septie:cmia as a condition in which both bacteria and their toxins are scattered throughout the body by means of the vascular and lymph sys tems; while pyremia represents a form of septi ea -mia in which, in addition to the general distri bution of septic material throughout. the body, this material containing bacteria becomes lodged at different points, thus setting up local foci of in feet ion known as metastatic absce*scs. These new abscesses usually occur along lines of easiest blood and lymph communication with the point or points previously infected. Thus in suppuration of the intestines the most common seat of me tastatic is the liver, while from septic foci in bones, muscles, skin, etc., abscesses may develop in lungs, kidney, spleen, and other organs. After death from pymnia there may be no visible changes, even the localized foci of infectiob being too small to be seen by the naked eye. The wound from which the infection originated may look in flamed or gangrenous. Extensive thrombi in the near-by veins are not uncommon.
Thrombosis may also occur in veins at a dis tance from the wound. In infections following amputation of the leg it is not uncommon to find the femoral vein filled with a purulent mass as high up as Poupart's ligament. As a result of the thrombosis, infarction or death of tissue from interference with its nutrition occurs. Metastatic abscesses may lie found in the lungs, kidneys, liver, intestines; in fact, in any of the viscera. Those in the lungs are ellictly near the pleural surfaces and in the lower lobes. Serous effusion, often with much fibrin, may occur into the pleural and pericardial cavities. Local inflammation of joints, especially of the knee and shoulder, may occur. With the excep tion of those occurring in serous membranes, these inflammations are usually purulent in character and of the same general nature as the metastatic abscesses. Ilieroseopical examination frequently shows congestion of the viscera, with acute degeneration of the parenchyma cells of the kidney, liver, spleen, etc. Chromatolysis of the cells of the brain and spinal cord occurs, also swelling of the lymph nodes with prolifera tion of their elements. An increase in the num
ber of white blood cells is of almost constant occurrence. While other species of bacteria act as occasional excitants of pyremia and septi ciemia, two species are so frequently associated with this condition that they have received the name of the pyogenic eocei. They are known as the staphylococcus and the streptococcus. The staphylococcus pyogcnes :wrens is the micro organism most frequently associated with suppur ation. It is a small round coccus averaging about one micron in diameter. It grows in groups somewhat resembling bunches of grapes, from which characteristic its name is derived. It is non-motile. It grows well on the ordinary cul ture media, such as beef broth, agar, gelatin, milk, and potato, at room temperature. On sonic of the media it develops a rich golden color, whence its name of aureus. It stains easily with aniline dyes, and does not decolorize with Gram's method. The staphylococcus pyogenes albus. so called from the whiteness of its colonies, is a less frequent less violent inciter of suppuration than the staphylococcus pyogenes aureus. It may occur in association with the latter or alone. The staphylococcus epidermis albus is a rather weak pyogenic coccus sometimes found in stitch abscesses.
The streptococcus pyogenes is also a common cause of suppuration and may occur either alone or in association with the staphylococci. Its effects are quite similar to those of the lococci. ITpon culture media it grows somewhat more slowly than the staphylococci and differs from the latter in not fluidifying gelatin. Its colonies are apt to be of a grayish color. It is non-motile, and when seen under the microscope shows its tendency to form chains, whence its name.
While the above are the most common ex citants of suppuration, other micro-organisms may act as causative factors. Thus the typhoid bacillus has been found in pure culture in acute suppurative inflammations of the middle ear, in osteomyelitis, in empya-ma, and in localized peri tonitis occurring during or after an attack of typhoid fever. The pnentnocoecus has been found alone in abseesses of the soft parts, in purulent eerebro-spinal meningitis, synovitis, pericarditis, and suppurative inflammation of the middle car. The bacillus soli eommunis has been found in pure culture in abscess of the liver, in appen dicitis, in acute peritonitis, in purulent inflam mation of the gall bladder, and in other inflam matory conditions. Among the less common ex citants of suppuration may be mentioned the gonocoeens, the microcoeeus tetragcnus, the bacillus pyrreyanus, the bacillus of glanders. the diplocovens of cerebro-spinal meningitis, and the bacillus pyogenes fictidus.