INFECTIOUS PAROTITIS. — Two forms of parotitis occur as the direct result of germ invasion: 1. Mumps; epidemic parotitis. 2. Metastatic, symptomatic, suppurative, or septic parotitis.
Infectious Parotitis, or Mumps.
Mumps is an acute, infectious, con tagious inflammation of one or both paro tid glands or other salivary glands, usu ally occurring epidemically. Although inflammation of the parotid glands may be caused by various germs, the disease commonly known as mumps gives every indication of being a specific disease. A period of incubation, the method of in vasion, and the definite course pursued mark the disease as a specific fever. No septic germ, however, has as yet been isolated.
Incubation. — The period of incuba tion is exceedingly variable. That most commonly observed probably lies between 16 and 20 days. It has been given by different authorities as follows: Flint, 10 to 18 days; Holt, 17 to 20 days; Ashby and Wright, 14 to 21 days; Smith, 19 to 21 days; Jacobi, 2 to 3 weeks; Dukes, 16 to 20 days; Dauchez, 15 days; Roth, 18 days; Henoch, 14 days.
Symptoms. — Premonitory symptoms are usually slight or entirely wanting. In rare cases malaise and headache pre cede the actual onset for a week. There is frequently a period of invasion last ing from twelve to twenty-four hours, marked by feverishness, headache, mus cular pains, anorexia, and perhaps vom iting. In very many cases the local symptoms are the first to appear. Pain is usually the first of these. It is stitch like in character and is located in the parotid gland, but radiates into the ear. It is increased by pressure and by all movements of the jaw. It increases in severity and in many cases becomes very intense. In other cases spontaneous pain is not felt, it being developed only upon pressure or movements of the jaw. Millet describes three painful points: one at the level of the temporo-maxillary articula tion; one below the mastoid apophysis; the third over the submaxillary gland. Swelling soon ensues, and first appears in the depression between the mastoid process and the ramus of the jaw, forc ing the lobe of the ear outward. At first the parotid gland alone is involved and the swelling assumes the character istic triangular shape, the upper angle being just in front of the ear. As the
surrounding tissues become involved, the triangular shape is lost. The cheeks, side of the neck, and regions behind the ear become swelled, the swelling in some instances extending almost to the shoulder. The tumefaction in front of the ear, however, remains as one of the distinctive marks of parotitis. The swelled area is often reddened, but more commonly the skin is normal in color and appearance. Over the gland the swelling is elastic to the touch, but the surrounding tissues are usually tous and have a doughy feeling and may even pit on pressure.
The pharynx and tonsils are frequently involved by the oedema, causing much discomfort. When the disease is uni lateral, the bead is inclined toward the affected side. When both sides are in volved, the head is held rigidly upright, as every movement causes pain. The ap pearance is characteristic and striking, and in extreme cases the patient becomes almost unrecognizable.
Both sides are usually affected before the attack runs its course. They may be attacked simultaneously, but more fre quently the inflammation occurs upon one side a day or two before it appears on the other. Of two hundred and twenty-eight cases reported by Holt, both sides were affected in two hundred and fifteen. The interval is sometimes a week or more, but more commonly it is not more than three days. In uni lateral mumps the left side is affected more frequently than the right.
The swelling commonly reaches its height on the third day, it remains sta tionary for two or three days, and then subsides with greater or less rapidity. The cedema of the surrounding tissues is the first to disappear. After the cedema has gone the gland is sometimes slow to gain its normal dimensions. Seven to ten days are required for the disease to run its course, but the duration of the illness depends also upon the interval be tween the involvement of the two sides. A patient of my own was confined to the house almost a month. The parotid on the right side was attacked a week after that on the left, and this was followed by orchitis on the eighteenth day.