=Complications and Sequels.=--These are frequent and make scarlet fever the most dreaded of the eruptive diseases, except smallpox. Enlarged glands under the jaw and at the sides of the neck are common, and appear as lumps in these sites. Usually not serious, they may enlarge and threaten life. Pain and swelling in the joints, especially of the elbows and knees, are not rare, and may be the precursors of serious inflammation of these parts. One of the most frequent and serious complications of scarlet fever is inflammation of the kidneys, occurring more often toward the end of the second week of the disease. Examination of the urine by the attending physician at frequent intervals throughout the course of the disorder is essential, although puffiness of the eyelids and face, and of the feet, ankles, and hands, together with lessened secretion of urine--which often becomes of a dark and smoky hue--may denote the onset of this complication. The disease of the kidneys usually results in recovery, but occasionally in death or in chronic Bright's disease of these organs. Inflammation of the middle ear with abscess, discharge of matter from the ear externally, and--as the final outcome--deafness, is not uncommon. This complication may be prevented to a considerable extent by spraying the nose and throat frequently and by the patient's use of a nightcap with earlaps, if the room is not sufficiently warm. Inflammation of the eyelids is an occasional complication. The heart is sometimes attacked by the toxins of the disease, and permanent damage to the organ, in the form of valvular trouble, may result. Blindness and nervous disorders are among the rarer sequels including paralyses and St. Vitus's dance. =Determination of Scarlet Fever.=--When beginning with vomiting, headache, high fever, and sore throat, and followed in twenty-four hours with a general scarlet rash, this is not difficult; but occasionally other diseases present rashes, as indigestion, _grippe_, and German measles, which puzzle the most acute physicians. Measles may be distinguished from scarlet fever in that measles appears first on the face, the rash is patchy or blotchy, and does not show for three to four days after the beginning of the sickness. The patient seems to have a bad cold, with cough, running at the nose, and sore eyes. German measles is mild, and while the rash may look something like that of scarlet fever, the patient does not seem generally ill, is hardly affected at all, though rarely troubled with slight catarrh of the nose. In no sickness are the services of a physician more necessary than in scarlet fever; first, to determine the existence of the disease, and then to prevent or combat the complications which often approach insidiously.