ADDISON'S DISEASE 279 



it rarely occurs in the extremes of life, cases have been reported in in- 

 fants and in octogenarians. Among the 320 cases above noted, the great- 

 est number of deaths (75) occurred during the sixth decade. Two cases 

 had passed the eightieth year. No social class is exempt from the disease, 

 but a large proportion of the cases appear to come from the working 

 classes. 



Among the predisposing causes commonly noted by writers are in- 

 cluded such factors as depressing conditions of life, prolonged worry, or 

 emotional shock, intoxications, alcoholism, heredity, and infections, es- 

 pecially malaria, influenza, pneumonia and tuberculosis ; and more re- 

 cently congenital anomalies of the chromaphil system. Only in rare in- 

 stances, however, is there any substantial evidence that such factors play 

 an important etiologic role. A few cases have been reported in which, 

 following some shock or depression, the disease has developed and run an 

 acute course. The strain of war has recently been alleged to be a factor 

 in the frequent incidence of this disease among soldiers, but Ramond and 

 Frangois, from a .study of such cases, are of the opinion that the great ma- 

 jority of these are ultimately tubercular in origin. Trauma, due to strains 

 or injuries of the back or abdomen, has been known to precede the onset 

 of the disease. Traumatic hemorrhage into the gland substance and 

 thrombosis of the adrenal vessels have been regarded, not infrequently, 

 as predisposing causes. Heredity is probably not a significant factor, 

 although a few isolated observations have been made of the occurrence 

 of the disease in different members of the same family, in one instance, 

 in the mother and four children (Fleming and Miller). Within recent 

 years, there has accumulated considerable evidence for regarding a con- 

 genital anomaly of the chromaphil system as an important predisposing 

 factor. 



In the great majority of cases (88 per cent), some destructive lesion 

 of the suprarenal glands has been found at autopsy. Tuberculosis of the 

 glands far exceeds other causes, atrophy ranking second. Syphilitic lesions 

 (gummata), new growths, or other organic changes, either involving the 

 suprarenals or the solar plexus and the semilunar ganglia, have been 

 noted in other instances. At times, no pathological lesion of the glands 

 has been encountered, an observation which has led some authorities to 

 assume that a purely functional disturbance of the glands may, in cer- 

 tain cases, be the etiological factor. 



Pathology. Pathological studies have not served to establish the 

 presence of any constant lesion of the suprarenal glands in this disease. 

 Autopsy records have shown that tuberculosis is the most common finding, 

 but normal glands have been occasionally reported (12 per cent in Lewin's 

 series). Atrophy of the gland is frequently encountered. Other lesions 

 are rare. Rolleston has summarized the various anatomical changes found 

 in the suprarenal glands post mortem, in the order of frequency of oc- 



