On account of the apparent analogy between pneumonia and the acute specific diseases, pathologists have searched carefully amongst the morbid products in the lung for signs of microscopic organisms, such as have been shown to exist in cases of erysipelas. Friedlander, of Berlin, in searching amongst the fibrinous effusions in the bronchial tubes, and in examining sections of the lung-tissue and inflamed pleura, found in each of eight cases submitted to investigation ellipsoidal micrococci which were coloured deeply by the aniline dyes. The organisms were found, as a rule, arranged in pairs or chains ; hut in some parts they swarmed in enormous numbers," especially in the interior of the alveoli and the lymphatic vessels. Koch, lilebs, and other observers have also described similar organisms.
Symptoms.—The onset of croupous pneumonia is sudden, and is usually marked by signs of great perturbation of the nervous system. The child is often convulsed, and the eclamptic seizures may succeed one another, with only short intervals of quiet, for hours together. In other cases the patient complains of severe headache and pains about the chest. He vomits repeatedly ; shivers or cowers over the fire ; and towards the evening may become delirious. From the first is high, the thermometer _ marking 103°-105°, or a still greater elevation. From the first, too, cough is noticed, and is a source of much distress from the pain it excites in the chest. The cough is characteristic. It assumes the form of a short, sharp hack, and in older children may be accompanied by the expectoration of a rusty sputum. The cheeks are brightly flushed ; the eyes look heavy, and the face is distressed ; the nares act ; the tongue is thickly furred ; epis taxis is a common symptom ; and the weakness is often from the first a notable feature in the case. This weakness often amounts to marked mus cular prostration. An infant lies quietly and takes no notice of what goes on around him. An older child seems stupid, and often makes no reply to questions addressed to him, as to do so requires an amount of exertion to which he feels himself unequal.
As the disease goes on there is little alteration in the symptoms. The child lies on his back in his bed. He is very thirsty, but has no inclina tion for food. His face continues flushed, and often a patch of herpes is seen on the upper lip. His breathing is hurried and short ; and its rhythm is altered, the pause taking place at the end instead of at the of inspiration. This is probably clue to an effort to suppress the cough. The peculiar character of the cough has been already referred to. It occurs in short single hacks, one to each short inspiration ; and these often continue until the child seems quite exhausted.
After three or four days the flush disappears from the cheeks, and the face is left pale, with a little lividity 'about the eyelids and mouth. The nervous symptoms also subside, and the nocturnal delirium rarely lasts longer than three or four nights. Usually the period of completion of the exudation is marked by a subsidence of the more severe features of the case. The temperature remains elevated, but the child looks less dull and self-absorbed ; his expression of distress passes away, and he takes some interest in what is going on around him. The period of resolution is marked by a sudden fall of the temperature, which sinks below the level of health, and the child passes rapidly into a state of convalescence.
The more special symptoms will now be considered in detaiL Nervous symptoms are, as a rule, more violent at the beginning of the disease. Convulsions cease after a few hours, and although delirium may persist for several nights, it rarely continues after consolidation has been completed. Severe cerebral symptoms are said to be more common in cases where the apex of the lung is the part to be attacked, but they are not limited to such cases ; indeed, in children they are often quite as marked when any other part of the lung is involved. It is very common to find a pneumonia of the apex unaccompanied by any sign of nervous irritation ; and according to my experience inflammation of this part of the lung, in the large majority of cases, runs in the child an especially short and favour able course.
When nervous symptoms occur the form they take is subject to con siderable variety. In infants there is usually great drowsiness, preceded, perhaps, by convulsions, and often accompanied by twitchings of the facial muscles and of the muscles of the limbs. Sometimes the child clutches at his mother's dress as if in fear of falling ; and when the drowsiness passes off he cries fretfully as if in pain. In an older child severe headache and delirium are usually the most prominent of the nervous symptoms. Thu's, a little girl, aged nine years, came back from school complaining of head ache and pains in the chest and back. For the next two days she vomited repeatedly, groaned with the pain in her head, and was delirious at night, lying with her head back and her arm's up to her forehead. There was no squint; nose bled once, and she coughed and expectorated phlegm streaked with blood. The child was seen at the hospital three days afterwards. Her temperature was then (6 P. m. ) 103°, and there was con solidation of the lower two-thirds of the left lung on the posterior as pect.