Lesions 769 



numbers in juice secured from a puncture made in the gland with a 

 hollow needle. This period of primary symptoms (chancre and 

 adenitis) includes part of what is known as the period of secondary 

 incubation, which intervenes between the appearance of the chancre 

 and that of the secondary symptoms. It usually lasts about six 

 weeks. During this time the organisms are multiplying in the 

 lymph-nodes and occasionally entering the blood. What fate 

 the organisms meet when they reach the blood in small numbers is 

 not yet known, but the slow invasion suggests that those first enter- 

 ing are destroyed, and that it is only when their numbers are great 

 and their virulence increased that they suddenly become able to 

 overcome the defenses and permit the development of the secondary 

 symptoms. The period of secondary symptoms corresponds to the 

 invasion of the blood by the parasite. It may cbntinue from 

 one to three years, during which time the patient suffers from 

 general symptoms, fever, etc., probably due to intoxication, and 

 local symptoms, such as alopecia, exanthemata, etc., due to local 

 colonization of the organisms. At the end of this period a partial 

 immunity, such as is seen in other infectious diseases (malaria), 

 develops, the organisms disappear from the blood, the general local 

 and constitutional disturbances recover, and the patient may 

 be well. Should he continue to harbor some of the micro-parasites, 

 however, there may be an insidious sclerosis of the blood-vessels 

 and parenchymatous organs consequent upon the growth and mul- 

 tiplication of the parasites, or there may be after many years a 

 period of tertiary symptoms characterized by the sudden appear- 

 ance of severe lesions in which the parasites are very few in number. 



The specific organisms are present in juice expressed from the 

 primary lesion, in juice from the buboes and enlarged lymph-nodes; 

 in the blood, in the roseola, and all of the secondary lesions, and 

 sparingly in the tertiary lesions. 



In congenital syphilis they reach the fetus from the ovum, the 

 spermatozoon, or the blood of the mother. Prenatal death from 

 syphilis is accompanied by lesions in which enormous numbers 

 of the organisms can be found, and furnishes the best tissues for 

 their experimental demonstration and study. 



Lesions. — The lesions of syphilis are so numerous that the reader 

 is referred to works on pathology and dermatology for satisfactory 

 descriptions. Here it may suffice to say that though diverse in 

 appearance and location, they have certain features in common. 

 The first of these, and that which naturally places syphilis among 

 the infectious granulomata, is the lymphocytic infiltration of the 

 tissues, with which all of the lesions begin. The second is a peculiar 

 form of necrosis — shmy when superficial, gummy when deep — with 

 which they terminate. The third is a tendency toward excessive 

 cicatrization. 



Diagnosis. — It is now possible to make a certain and early diag- 



49 



