In a collection of cases of phthisis taken from the Cincinnati Hospital records, amounting to 1266, there were of
| Cases of | hæmoptysis | 475, | or 37.51 | per cent. |
| " | phthisis, with family history of same | 332 | ||
| " | hæmoptysis in same | 127, | or 38.25 | " |
| " | acquired or non-inherited phthisis | 934 | ||
| " | hæmoptysis in same | 348, | or 37.25 | " |
In 10 cases there was a family history of hæmoptysis; that is, of a general family peculiarity in that direction. These percentages show no great difference between the relations of inherited and non-inherited phthisis to hæmoptysis, the inherited exceeding by 1 per cent. that of the non-inherited form.
Without here attempting a comprehensive statement of what the predisposition, transmitted or acquired, is, we may mention two influences of important force—a tendency to fragility of vessels and to the catarrhal disposition. It is sufficient to speak of the fact that in no other disease of the lungs than phthisis have we as a common feature this vascular fragility. It differentiates the disease and the symptoms. If it appear in any of them, it should at once excite a suspicion of the phthisical constitution. That it does appear in some such cases without ulterior effects does not invalidate the general statement. It may be put down as a part of the phthisical habit directly concerned in the liability to hæmoptysis. The proof of this proposition is more clinical than anatomical.
The attempt to prove that it is hæmophilic rests upon the application of a few histological examinations of hæmophilic vessels to the phenomena of phthisical hæmoptysis. The assumption of identity has only the doubtful force of analogy. Histological examinations of the vessels in the earliest stages of phthisis and hæmoptysis are too rare to afford sufficient data. In the latter stages the condition is too complex, because of positive inflammatory and ulcerative processes.
Although alterations in the vessels in the early stage of simple inflammation cannot be histologically demonstrated, yet they must exist in order to allow diapedesis. So with early phthisis: in the pre-hæmoptoic stage the alterations are not demonstrated, yet that such disorder of function must have accompanying structural change underlying the phenomena of the initial hæmoptysis is in accordance with physiological and pathological doctrines, and has much consistent clinical force. When we presuppose a delicacy of, or injury to, the blood-vessels of a part, there is the imminence of not only a rupture, and consequent hemorrhage, but of those changes which, leading through stasis and congestion, come to be inflammatory, and which affect still further the vascular structures and adjoining parenchyma.
Besides these changes initiated in the blood-vessels, there are others of close relation to the phthisical constitution, which begin in the vulnerable epithelial elements of the bronchial mucous membrane and of the air-cells. They are the evidences of the dispositio catarrhalis, which received its name from the old observers, and the validity of which has been confirmed by modern pathological and clinical researches.
It is responsible for the great susceptibility to catarrhal affections of the bronchi and air-cells which lays the foundation for chronic catarrhal pneumonia.
These two elements, of fragility of vessels and of the catarrhal tendency, are the tangible instruments of heredity. They are also the factors of the acquired predisposition.
The Vienna Hospital reports, running through more than fifteen years, and embracing more than 20,000 cases, give as the ages most liable to hæmoptysis those between eighteen and twenty-nine years. No statistics as to sex are given.