Delirium may pass into coma. When delirium and headache are marked symptoms, muscular tremors (subsultus tendinum) are very apt to occur, with insomnia and frightful hallucinations. Indeed, these cerebral symptoms are often so prominent in alcoholic pneumonia, and occur so early, that the pneumonia may be wholly masked, and will only be discovered by the temperature-range and by a careful physical exploration of the chest.
When delirium is present in feeble patients, it assumes a low muttering typhoid type, and a state of stupor is soon reached.
Among the rare nervous symptoms met with in pneumonia may be mentioned photophobia, disturbances of vision, and deafness.
In children the cerebral symptoms are more prominent than in adults, and they do not seem to be influenced by the extent of lung involved. Stupor and restlessness on the one hand, or headache, delirium, and convulsions on the other, may usher in pneumonia in children without any prodromata.
Sometimes children pass rapidly into a semi-comatose condition which has not been preceded by delirium or convulsions. Convulsions are as common in children as they are rare in adults, and occur with greatest frequency and severity during dentition. The convulsions may be general and resemble those of epilepsy (pneumonie éclamptique of Barthez and Rilliet), or they may attack single muscles or groups of muscles, the child occasionally passing into a tetanic or opisthotonic condition.
If convulsions do not occur until late they are quickly followed by a deep and fatal coma. A very rare occurrence is partial paralysis of the muscles which were involved during the convulsive period. Such paralysis is often permanent. Again, the cerebral symptoms may closely resemble those which attend cerebro-spinal meningitis—viz. headache, constipation, great prostration, delirium, convulsions, opisthotonos, and strabismus. As in meningitis, there is a peculiar cry, and all the symptoms may point directly to the brain. These symptoms are most likely to be present in the pneumonia of the apex in children from five to seven years of age.36
36 This form is the pneumonie méninges of Barthez and Rilliet.
In senile pneumonia headache may persist throughout the entire attack; it is usually accompanied by delirium of a mild type, especially when the apex of the lung is involved. These patients are very loquacious and have a constant desire to get out of bed.
Alimentary Tract.—The symptoms referable to the digestive apparatus are neither diagnostic nor important. Nausea and vomiting are not infrequent, and in about 15 per cent. of all cases are among the initial symptoms. Gastric symptoms, when severe and persistent, greatly endanger life. There is no characteristic appearance of the tongue: it may be normal throughout, or covered with a creamy-white fur, which becomes dry and brown as the disease advances. In severe cases and toward the end of the disease the lips and tongue become brown, dry, and cracked, and sordes collect on the teeth. Anorexia is marked at the onset, and the thirst is intense. When convalescence commences the tongue becomes clean and the appetite returns. Occasionally there is a catarrh of the oral mucous membrane. Diarrhoea may occur as one of the initial symptoms. It is most apt to be present when there are nausea and vomiting. As a rule, the bowels are constipated and the stools dry. In young children nausea and vomiting are more common, and in 50 per cent. of the cases usher in the disease. They usually cease on the second day, although they may persist until the crisis occurs. Excessive and violent diarrhoea may precede a fatal termination.
In senile croupous pneumonia the tongue early becomes dry, shrivelled, and covered with a thick brown coating, and is protruded with difficulty. Although these patients do not complain of thirst, they take with avidity fluids that are placed to their lips. As the period of crisis is reached critical diarrhoea is of frequent occurrence.