In the present stage of our knowledge, many of these post-influenzal lungs will not be diagnosed properly until sufficient time is given for either the lung to clear up or the tubercle bacillus to appear in the sputum. We would emphasize the importance at the present time of finding the tubercle bacillus in all suspicious lung lesions before giving a positive opinion as to the tuberculous nature, even though the physical signs are very definite.
Another group of sequelæ is that due to thyroid disturbance, or disturbance of the endocrin system in general. Since the epidemic a number of patients have been seen who noticed an enlargement of a previously normal thyroid gland or greater enlargement of a previously hypertrophied gland. In the same way the symptoms of hyperthyroidism appeared, new in some or a recrudescence in others.
In some of these there was a disturbance of carbohydrate metabolism, as shown by an occasional glycosuria and an increase in the blood sugar, or by a possible disturbance of the suprarenals, as brought out by the administration of adrenalin hypodermatically (Goetsch test). In the application of this test in post-influenzal patients it appeared that the whole endocrin system was in a state of imbalance.
It appears to us not at all improbable that the so-called psychoneuroses of which fatigue, nervousness, irritability and tachycardia play such an important part might also be explained in the same way. These constitute a group of sequelæ which were frequently recognized after previous epidemics, and which are again coming to the foreground.
We are of the opinion, on account of the apparent absence of any specific pathology of the gastro-intestinal tract and its appendages during the attack of influenza, that the sequelæ referred to the digestive system are largely due to exacerbations of previous physiological disturbances or pathological processes. The patient with a previous peptic ulcer has a recurrence of his ulcer. The patient with an infection of the biliary tract has an acute exacerbation, or may have an attack of biliary colic. In fact, there seem to have been many more cases of this kind since the epidemic than before, and most of the patients date the time of the onset from a period soon after recovering from influenza.