In cases so slight it is no easy matter to recognise the features of a highly dangerous disease; still, out of forerunners so trivial as these, croupal symptoms may be developed, and their advances may be most insidious, and unless both parents and doctor have been closely on the watch they may be surprised all at once by the breathing suddenly becoming very laboured, by that and the cough becoming attended by the sounds characteristic of croup, and by the child's life being in extreme jeopardy, or in danger even beyond the hope of recovery.
It is not that here, as in cases of catarrhal croup, the ailment has really come on suddenly, but that the disease has been silently making unsuspected progress. Whenever then a child, after a few days of slight causeless ailing, accompanied with some little discomfort in swallowing, is seen to have white patches at the back of its throat, do not allow yourselves to be lulled even by their disappearance into a feeling of absolute security. Watch the child, and beg the doctor to watch it carefully, until it is perfectly well again, for though the deposit may have disappeared from the back of the throat it may continue to be formed in the windpipe, and in the somewhat depressed state of the nervous system which attends diphtheria it may not excite that irritation which any such cause would produce in a child in perfect health, and consequently not announce its presence until its amount has become so considerable as to offer an almost insurmountable obstacle to the entrance of air. Any, even the slightest, hurry of breathing, a hissing sound when the child draws its breath, hoarseness of voice, or a ringing cough, should quicken your apprehension of danger, and make you seek for immediate help.
It may be as well, however, to mention here, that not every white speck seen at the back of the throat is of necessity due to diphtheria, but that in some cases of ordinary sore-throat white spots may form on the surface of the tonsils. These white spots are due to the collection at their openings of the secretion formed in the minute glands which beset the surface of the tonsils, and which at these seasons is poured out in greater abundance than usual. They are distinct from each other, and do not coalesce into a membrane; the surface beneath is not the uniform red shining surface on which the membrane in diphtheria has formed, but the separate tiny openings from which the white matter has exuded may be distinctly seen if the surface is wiped with a camel's-hair brush. It is, of course, wise in every case to leave to the doctor the decision as to the nature of the deposit, but it may sometimes relieve needless anxiety to know beforehand that there is another cause besides diphtheria to which white spots at the back of the throat may be due.