Etiology. — Adenoid vegetations are common and especially peculiar to child hood. They pre-eminently characterize early life and sometimes affect several members of one family at the same time.
Sajous states that heredity is an im portant etiological factor in many eases, and that in this country adenoid growths seem to be oftener prevalent among fe males than males.
In 2000 patients, or 42.9 per cent., t re the subjects of disease of the tonsils pliar.‘ngeal, and lingual), and tht rt•by induced to seek relief from the symptoms for ,a idyll they were in all t .1 Sl S , and in many instances %%holly, responsible. Enlargement of these tissues soniew hat more common in the female sex. In hypertrophy of the lymphoid material at. the base of the tongue the female shows a very de cided preponderance over the males. UP to the fifteenth year the males suffering from adenoids are slightly more numer ,ms than females (238 to 209); after this period. however, the proportions are directly reversed, and continue so. In hypertrophy of the tonsils alone the pro portions up to the fifteenth year are practically the sante; afterward the number of females is more than double that of males. Of the 2000 patients, 1123 were females and SS7 males. In 2000 observations the following percent ages were found:— The abundance of lymph-follicles in the retronasal space of children affords an explanation for the frequent appear ance of the disorder in early life. The diseaFe may be preFent at birth or it may commence during the first or second year.
Between three and fifteen years seems to be the period of life in which the dis ease is most common. Yet, as a general rule, the third year is the time when evidences of post-nasal adenoid hyper trophy become manifest. Adult life is by no means exempt from the trouble, for it is not an unusual thing to see per sons whose ages range from eighteen to thirty-five years, or even more, suffer from the disorder.
Of 32 cases examined for adenoid vege tations, 17 We re in patients from 5 to 14 years. A. "Michel Dansac (Annales des Mal. de l'Oreille, etc., July, '93).
Six eases in nurslings under six months old, one. of these being but one month
of age. Huber .(Archives of Ped., Jan., '94).
As the total result of examination of 500 cases of adenoids the conclusion reached that adenoids are most com monly met with between 6 and 15, but that they are fairly common under 5 years and between the ages of 15 and 20. Sex seems to exercise a very small influence, the figures being 263 males and 237 females. Heredity has a very considerable influence. Out of the 500 eases there were thirty patients who had either one or more brothers or sisters affected in the same way; in nine in stances there were two only, and in four there were three members of the same family affected. Damp atmosphere favors the occurrence of symptoms in those who have hypertrophied pharyn geal tonsils, while opposite conditions tend to diminish the nasal obstruction, when it exists. Among deaf-mutes it has been shown that adenoids are much more frequent than among other chil dren. P. McBride and A. Logan Turner (Edinburgh Med. Jour., Apr., '97).
Lymphoid tissue in childhood is very easily excited into active growth, the faucial tonsils and cervical glands taking on active inflammation under trifling in fluences. Chronic hypertrophy is chiefly brought on by repeated or continued in flammations of the tissue.
The amount of tissue sufficient to pro duce marked symptoms of hypertrophy in children does not cause similar condi tions in adults, because as adult life is approached the naso-pharyngeal cavity increases its dimensions, thus overcom ing by degrees the amount of obstruction. Not infrequently only remnants of the disease in the form of irregular thicken ings of the mucous membrane are found in adult age, which predisposes to acute exacerbations of post-nasal catarrh. The predisposition of adenoid growths as the individual grows older is to atrophy and disappear spontaneously.
The researches of Meyer have demon strated that adenoid vegetations occur in all climates and affect people of all nations. A damp, cold climate seems to favor more especially their production. The rheumatic or strumous diathesis seems to predispose to their development.