Pertussis.

Synonyms.—Whooping-cough; Tussis Convulsiva.

Definition.—A specific infectious disease occurring epidemically, and characterized by a peculiar, spasmodic, paroxysmal cough, ending in a whoop. The whoop is caused by the air rushing through the contracted larynx during a prolonged inspiration which follows a paroxysm of coughing, the air in the lung being completely exhausted by the effort. The disease usually attacks children under ten years of age, though no age is exempt. It is also characterized by catarrh of the respiratory tract.

Etiology.—The cause of whooping-cough has always been a matter of conjecture, and various theories have been assigned to account for the lesion. Some have regarded it as a laryngitis, others as a bronchitis.

Friedleben believed that the pressure of the swollen tracheal and bronchial glands upon the filaments of the pneumogastric nerve gave rise to the disease. Baginsky showed by experiment that the superior laryngeal nerve is the nerve that excites cough, and as the posterior laryngeal wall, just below the vocal cords, was supplied by this nerve, an inflammation of the larynx would give rise to a spasmodic cough. Many others contend that the disease is purely a neurosis, and that the toxin, whatever it may be, spends its force upon the medulla, pneumogastric, phrenic, recurrent laryngeal, or sympathetic nerves.

The general belief at present is, that, like other contagious diseases, it is caused by a specific germ, and many observers have been diligently working to isolate it. Afanassieff and Koplic have found what they believe to be the specific germ. Afanassieff termed it the bacillus tussis convulsivae. Koplic has more recently isolated a bacillus which very much resembles the one found by Afanassieff, yet differing in some respects, and this he claims to be the genuine article; nevertheless all have failed when brought to the crucial test, and we are still in the dark as to the exact germ.

All we know is, that it is a specific contagion, and that the unprotected, coming in contact with a person suffering with the disease or entering a room where a patient has been staying, will contract the disease.

It occurs as an epidemic, though it is more likely to be endemic in all large cities. Spring and fall are the most favorable seasons for the disease. One attack secures an immunity from the disease. While it prevails largely in children under ten years of age, I have seen it with all its severity in an old man past seventy.

Pathology.—There is no lesion which can be said to be characteristic of whooping-cough in an uncomplicated form. In the early stage there is slight catarrh of the nose and pharynx, which may extend to the larynx, trachea, bronchi, and lungs. In the advanced stage, especially in delicate children, we may find more decided pulmonary changes, such as emphysema, broncho-pneumonia, pulmonary collapse, and great congestion of the lungs; but these anatomic changes are the results of complications, and not characteristic of the disease.

Symptoms.—Authors have divided the disease into three stages following the period of incubation, though they are not always well defined. They are,—(1) The catarrhal stage; (2) The spasmodic stage; (3) The stage of decline.

The period of incubation varies from a few days to two weeks, depending largely upon the susceptibility of the patient, the virulence of the epidemic, and the resisting power of the child, or upon his vitality. This period comes on so insidiously that the prodromal symptoms are ill defined, and the first evidence of the disease is the catarrhal stage.

The child appears to have taken cold. There is some irritation of the Schneiderian membrane, with increased secretion from the same, and also increased secretion of tears, with more or less hoarseness. The cough, even in the early stage, is suggestive, coming on in paroxysms, though at this time the characteristic whoop is absent. The patient at this period is considered by the mother to have taken cold, and the favorite cough mixture is prescribed; this facing, the physician is consulted, who many times makes the same mistake, only to be discovered when the whoop develops.

The patient now begins the cough with a full inspiration, and continues it till the air is entirely expelled from the lung and the child is completely exhausted. The paroxysm is made up of a series of sharp, hard, exasperating, and explosive coughs, and during its continuance the patient presents to the anxious mother an alarming and frightful appearance.

As the cough progresses, the child becomes red in the face, the color soon changing to a livid or purplish hue; as the violence increases, the eves seem as though bursting from their position, the lips become swollen, the veins of the neck become distended, and sometimes blood bursts from the nose, mouth, and even the eyes or ears. A glairy, tenacious mucus is expelled as the result of the severe coughing, and frequently vomiting ensues, especially if a paroxysm of coughing comes on soon after taking nourishment.

During this time there is a spasmodic closure of the glottis, and when the paroxysm is over, the child gasps for breath, and the air, rushing through the contracted larynx, gives rise to the whoop. If the paroxysm has been very severe, the child is limp and exhausted for some moments; at other times he resumes the play, interrupted by the fit of coughing, as though the attack was of no importance.

There may be only three or four attacks in twenty-four hours, or they may occur as often as every thirty or sixty minutes.

If the chest be examined during an attack, we will find dullness during expiration, and resonance full and clear during inspiration. The respiratory murmur is, however, indistinct or absent, owing to the small amount of air passing through the contracted glottis. During the intervals of the paroxysms, various sounds are heard, depending upon the complication. This stage continues from two to four weeks, when the stage of decline follows. There is nothing peculiar to this stage, simply a gradual subsidence of the preceding symptoms.

The paroxysms are increased by exciting the emotions, fits of crying almost invariably bringing on an attack. The inhalation of any irritant will also prove an excitant.

Complications.—The complications are numerous, and give, to an otherwise harmless disease, a degree of danger. A common, though not dangerous, complication is hemorrhage, which may be from the nose or the lung.

Vomiting may be frequent, and at times so severe as to give rise to gastric derangement, resulting in anemia or general marasmus. Ulceration of the frenum linguae is quite common.

The more serious complications, however, are those of the respiratory and circulatory apparatus. As a result of a severe paroxysm of coughing, there may be a rupture of the pulmonary alveoli, giving rise to interstitial emphysema. Broncho-pneumonia, so often attended by collapse, is one of the most serious and fatal results. Enlargement of the bronchial glands often occurs, and, when the patient is delicate or bottle-fed, may lead to tuberculosis. As a result of the great strain upon the heart, valvular troubles are not uncommon. Convulsions are not frequent, though occasionally seen.

Diagnosis.—The diagnosis is readily made after the characteristic whoop develops; before this we may not be positive, although the catarrhal symptoms, hoarseness and spasmodic cough, are suggestive of the trouble.

Prognosis.—Although this affection has been regarded as one of the fatal diseases, Dolan ranking it third in fatality in children's diseases in England, I have never been able to understand the large mortality attributed to it, and an experience of nearly twenty-five years bears me out in saying that the prognosis should nearly always be favorable.

In very young, bottle-fed, delicate babies, with pulmonary complications, the prognosis should be guarded, otherwise it is favorable.

Treatment.—While I do not claim that we have a specific treatment for this troublesome affection, I do claim that the cough can be so modified and the disease so controlled that the mortality will be very small. Belladonna, given in small doses, is one of our best remedies; add five to ten drops of the specific tincture to half a glass of water, and give a teaspoonful every one, two, or three hours. Our "regular" brother is beginning to recognize its value, for Jacobi regards it as the most satisfactory remedy for this disease. The indications are the same as in other troubles,—dullness, with capillary congestion.

Drosera is called for when the child is hoarse and the cough croupal in character. Bromide of ammonium, where the most marked symptom is the convulsion or spasmodic character of the cough. Dr. Webster speaks very highly of magnesium phosphate 3x. An infusion of red clover blossoms, recently cured, to which may be added simple syrup, is an old domestic remedy of much virtue. Burning a little sulphur in the sleeping-room before putting the child to bed will often insure a good night's rest.

Dr. W. P. Best, of Indianapolis, presented a paper on "Solanum in Whooping-cough" at our National Medical Association, giving his experience with this drug. So favorably was he impressed with the drug, that he sent me a trial bottle. After using it in a number of cases, I am convinced that in solanum we have almost a specific for this troublesome disease.

Bromoform, in from one to five minims suspended in syrup, has recently been highly recommended, though in my hands it has not been as successful as the above described remedies. Inhalations sometimes afford relief.

During convalescence the child should be carefully watched, as it is at this time pulmonary complications are so liable to occur. If the child be delicate and the parents be able to profit by the prescription, a change of climate affords great benefit during the stage of convalescence.

The Eclectic Practice of Medicine, 1907, was written by Rolla L. Thomas, M. S., M. D.