#Acquired Syphilis in Infants and Young Children.#—­When syphilis is met with in infants and young children, it is apt to be taken for granted that the disease has been inherited.  It is possible, however, for them to acquire the disease—­as, for example, while passing through the maternal passages during birth, through being nursed or kissed by infected women, or through the rite of circumcision.  The risk of infection which formerly existed by the arm-to-arm method of vaccination has been abolished by the use of calf lymph.

The clinical features of the acquired disease in infants and young children are similar to those observed in the adult, with a tendency, however, to be more severe, probably because the disease is often late in being recognised and treated.

CHAPTER X

TUMOURS[2]

Definition—­Etiology—­General characters of innocent and malignant
    tumours.  CLASSIFICATION OF TUMOURS:  I. Connective-tissue tumours: 
    (1) Innocent:  Lipoma, Xanthoma, Chondroma, Osteoma,
    Odontoma, Fibroma, Myxoma, Endothelioma, etc.; (2)
    Malignant:  Sarcoma—­II.  Epithelial tumours:  (1) Innocent: 
    Papilloma, Adenoma, Cystic Adenoma; (2) Malignant: 
    Epithelioma, Glandular Cancer, Rodent Cancer, Melanotic
    Cancer—­III.  Dermoids—­IV.  Teratoma.  Cysts:  Retention,
    Exudation, Implantation, Parasitic, Lymphatic or Serous. 
    Ganglion.

[2] For the histology of tumours the reader is referred to a text-book of pathology.

A tumour or neoplasm is a localised swelling composed of newly formed tissue which fulfils no physiological function.  Tumours increase in size quite independently of the growth of the body, and there is no natural termination to their growth.  They are to be distinguished from such over-growths as are of the nature of simple hypertrophy or local giantism, and also from inflammatory swellings, which usually develop under the influence of a definite cause, have a natural termination, and tend to disappear when the cause ceases to act.

The etiology of tumours is imperfectly understood.  Various factors, acting either singly or in combination, may be concerned in their development.  Certain tumours, for example, are the result of some congenital malformation of the particular tissue from which they take origin.  This would appear to be the case in many tumours of blood vessels (angioma), of cartilage (chondroma), of bone (osteoma), and of secreting gland tissue (adenoma).  The theory that tumours originate from foetal residues or “rests,” is associated with the name of Cohnheim.  These rests are supposed to be undifferentiated embryonic cells which remain embedded amongst fully formed tissue elements, and lie dormant until they are excited into active growth and give rise to a tumour.  This mode of origin is illustrated by the development of dermoids from sequestrated portions of epidermis.