Tetany.

What is the etiology of tetany?

Tetany is most common in infancy and early adult life, when males are more prone to the disease than females. Occurring later in life, females are affected in larger proportion. In some cases, an hereditary influence can be made out. In many, diarrhea is an exciting cause. In others, the disease has been preceded by one of the acute infectious diseases. Pregnant or nursing women seem especially predisposed. The disease has been observed to develop in a considerable number of cases following removal of the thyroid gland. It has also been seen in association with dilatation of the stomach. In children it is often associated with rachitis, laryngismus stridulus, carpo-pedal spasm and convulsions. Other possible causes are exposure to cold and blows and injuries. Epidemics of the disease have been observed.

What are the symptoms of tetany?

Tetany is an affection characterized by muscular spasm, of symmetrical distribution, which usually begins and is most marked in the extremities.

The spasm may be continuous, remittent or intermittent.

A paroxysm may be induced by compression of the vessels and nerves of a part.

At the onset of the attack, there may be headache, vomiting, spinal pain, numbness and tingling. There may be moderate elevation of temperature.

In the intervals between paroxysms, the mechanical excitability and electric irritability of nerve and muscle are heightened. The disease may continue for a period ranging from a few days to several months.

Cases in which the spasm is intermittent are longer in duration than those in which the spasm is continuous.

How are tetany and tetanus to be distinguished?

The spasm of tetany is more likely than that of tetanus to be intermittent. Trismus is an early symptom of tetanus; if

it occurs at all in tetany, it appears late. The participation of the extremities in the spasm is a feature of tetany.

Hydrophobia.

What are the clinical features of hydrophobia?

Hydrophobia results from the inoculation of man with rabies of animals. The infection is usually transmitted by the saliva of a rabid beast, as a dog, a cat, a fox, or a wolf, through a bite or a preexisting wound. The period of incubation of hydrophobia is extremely variable, but is on an average from six to ten weeks. During this time, the primary wound may have healed, and no symptom have been present. Local pain may be perceived preceding the development of the disease proper, with the onset of which there are a sense of malaise, mental depression and slight difficulty in swallowing. Sleep is impaired and there may be respiratory spasm. The stomach now becomes intolerant, rejecting everything introduced. The muscular spasm extends and cutaneous hyperesthesia becomes manifest. External stimuli readily induce convulsions. The mental distress becomes intense. The temperature is elevated. Priapism may occur. Albumin and sugar are sometimes found in the urine. Ultimately, paralytic phenomena may supervene. Death may result from exhaustion, by reason of the inability to retain food, and the violence of the convulsions; from suffocation, as a result of respiratory spasm; or from heart-failure.

How are lyssophobia or pseudo-hydrophobia and true hydrophobia to be differentiated?

Persons who have been bitten by animals, rabid or not, develop a state of fear and dread, sometimes difficult to distinguish from true hydrophobia. Usually, however, the laryngeal and pharyngeal spasm characteristic of hydrophobia is wanting, while judicious moral assurance may cause a dissipation of the symptoms.

How are hydrophobia and tetanus to be differentiated?

In hydrophobia there is the history of a bite, with a long period of incubation; in tetanus of wound-infection with earth, and a short period of incubation. In hydrophobia, respiratory and pharyngeal spasm is an early manifestation; in tetanus, trismus is among the first symptoms. In the former all food is rejected; in the latter, if food can be introduced into the mouth, there is no difficulty of retention. Tetanus does not present the intensity of mental distress and disturbance encountered in hydrophobia.

Aural Vertigo-Labyrinthine Vertigo.

What is aural vertigo?

Meniere's disease, aural or labyrinthine vertigo, is an affection dependent upon a pathologic condition of the terminal fibers of the auditory nerve in the labyrinth. The disease of the labyrinth may be inflammatory, gouty, syphilitic or degenerative. The symptoms occasioned are impairment of hearing, tinnitus aurium and vertigo. The last is aggravated in paroxysms, in which in addition there are nausea and vomiting, with pallor of the face and cold sweats. The patient may fall to the ground and the vertigo be so intense that he is temporarily unable to arise.

How are epilepsy and aural vertigo to be differentiated?

Epilepsy is, and aural vertigo is not, attended with muscular spasms and loss of consciousness. In the intervals between the paroxysms of aural vertigo some degree of dizziness persists and there are also impairment of hearing and tinnitus aurium, which are not accompaniments of epilepsy.

Exophthalmic Goiter.

What are the symptoms of exophthalmic goiter? Exophthalmic goiter, also called Graves's disease and Basedow's disease, is an affection characterized by increased frequency of action and palpitation of the heart, protrusion of the eyeballs

and enlargement of the thyroid gland. Its pathology is not yet established. It is clinically a vaso-motor ataxia, and has long been considered a disease of the sympathetic nervous system, especially of the cervical ganglia. There is growing evidence, however, that the disease is dependent upon a lesion of the floor of the fourth ventricle, with which many of the symptoms would harmonize.

The disease is more common in females than in males, and in adult life than at any other period. In some cases a neuropathic heredity can be traced. The exciting cause is usually mental emotion, shock, grief, anxiety.

(After Wilks.)

Palpitation of the heart, associated with or independent of an organic lesion, is one of the earliest symptoms. The action

and

of the heart is increased both in frequency and in energy, is often extremely irregular. The tachycardia and the palpitation may reach a high degree of intensity, the pulse sometimes exceeding 140 in the minute. There may also be evident pulsation in the arteries and a bruit in the vessels of the neck.

Anemia is often an early symptom. In the progress of the case, the eyes protrude and the thyroid gland becomes enlarged. The exophthalmos and the goiter may each be symmetrical or unilateral; the protrusion and the enlargement, respectively, are not uncommonly greater upon the right side. In some cases, the upper lids are retracted, displaying the sclerotic, and do not follow the eyes when the glance is depressed. This lagging of the lids is called "Von Graefe's sign.”

Over the enlarged thyroid gland a blowing systolic bruit is usually to be heard. The goiter frequently pulsates; it is at first usually elastic; ultimately it may become firm. The appearance of the goiter may be intermittent; when permanent, the enlargement may undergo spontaneous variation.

Among other symptoms are nystagmus, tremor of the extremities, an abnormal sense of heat, flushing and perspiration. It has been stated that the bodily electric resistance is diminished. Various cutaneous affections have been noted. In women, menstruation is commonly deranged.

In some cases, albuminuria, in others, diabetes has been observed. Hemoptysis, hematuria, hematemesis and other hemorrhages, and sometimes purpura, occur. Mental changes are not uncommon. Mania is an occasional complication.

Exophthalmic goiter is not directly fatal. Spontaneous recovery is possible. Temporary exacerbations take place. What are the features distinguishing exophthalmic goiter from simple goiter?

Occasionally, the enlargement of the thyroid gland may be the first symptom of exophthalmic goiter observed. The bruit heard over the gland in exophthalmic goiter is wanting in the simple enlargement. Then, investigation will disclose the existence of palpitation and examination will reveal increased rapidity of the action of the heart, with the development, in the progress