Part 25

The nasal mucosa may show only petechiæ and circumscribed blood staining, but in fatal cases it is more likely to present extensive blood extravasations involving it may be the whole mucosa, and narrowing the lumen almost to complete occlusion. Sloughing is not rare, and the resulting ulcers may extend into the subjacent tissues, so as to penetrate the septum nasi or the thin plate of the turbinated bone.

The buccal mucosa and submucosa are often involved in common with the skin of the lips, cheeks, and intermaxillary space, the tissues being involved in one common infiltration of blood and serum. In some cases circumscribed necrosis and ulcerations are formed.

In the pharynx and larynx infiltration of the mucosa and adjacent parts of a deep blood red, with or without ulceration, causes serious narrowing of the passage, that on the vocal cords threatening suffocation. Suppuration of the pharyngeal glands and guttural pouches is not uncommon. Alimentary matters are frequently found in the larynx, and bronchia.

Beside the petechiæ and hæmorrhages in the lungs, œdematous infiltration in dependent parts, hepatization, abscess, and limited areas of necrosis are met with. The pleural sacs often contain a sanguineous effusion.

The stomach and intestines are usually more or less mottled with petechiæ involving mucosa, serosa or muscular coat; they are raised in rounded or irregular elevations by œdemas; or they are the seats of more or less extensive and even perforating ulcers. The contents of the bowels may be deeply discolored by the escaping blood.

The kidneys may be pale except where blood stained and œdematous infiltration of the surrounding tissue may be marked. Serous effusion into the peritoneum is not rare.

The eyelids are often implicated, infiltrated thickened, and rigid, and the conjunctiva, bulbar and palpebral, the seat of extensive petechiæ.

Barreau mentions extravasations on the divisions of the lumbosacral plexus causing sudden paraplegia.

Petechiæ and hæmorrhages mark endocardium, pericardium and cardiac muscle, otherwise the muscle is pale. The blood is sometimes in firm clot, at others diffluent or nearly incoagulable.

Symptoms. If hyperthermia is not already present as a feature of the pre-existing malady it usually shows itself early, at first slight, it may be (101° F.), and afterward rising in some cases to 104° to 106° F., or even higher. The general symptoms are usually those of the pre-existing disease (strangles, contagious pneumonia, influenza, nasal catarrh, pharyngitis, bronchitis, etc.), pursuing, it may be, a persistent course, or attended by special toxæmic symptoms of prostration and other signs of depression of vital functions. In some cases the hyperthermia is either absent at this stage or overlooked. On the prostration supervene the petechiæ on the visible mucosæ, and often also the swellings of the skin and subcutis. One of these may be seen before the other and it is difficult to decide whether the petechiæ always appear first as has been claimed. Cadeac claims that when œdema is first seen it has been preceded by petechiæ in that tissue (skin).

The petechiæ are usually first noticed on the nasal mucosa as fine red points, pin’s heads, or up to half an inch in diameter, or a number of these have coalesced to form extensive patches, and by and by to cover the entire wall. At first the mucosa is spotted with purple, without any marked elevation of the surface, but as the lesions extend it becomes swollen and raised at the points of extravasation and immediately around them and oozes a serous, sometimes a pinkish or yellow fluid. Even in the smallest petechiæ the color is persistent and does not disappear on pressure like the blush of the adjacent mucosa.

Usually cutaneous swellings coincide with the petechiæ, or appear within two days thereafter. The first manifestation is in the form of rounded abruptly elevated nodules, about 1½ inch to 3 inches in diameter, strongly resembling the eruption of urticaria. These show a certain predilection for the more dependent parts of the body,—limbs, abdomen, sheath, mammæ, sternal or pectoral region, nose, lips, face, etc.,—but they may develop on any part or on the whole surface. Neither tenderness nor heat is usually excessive. The swellings tend to run together so as to form extended elevations enveloping the entire limb up to a given point, forming a great pad under the chest and abdomen, or distending the whole face or head so that it seems more like that of a hippopotamus than of a horse. In such cases the lips and nostrils become so thick and rigid that prehension is impossible, and breathing if it can be accomplished at all is accompanied with a marked snuffling. The swollen eyelids are closed, and the general turgid surface of the face is hard and resistant and no longer pits on pressure.

Under the chest and abdomen the swellings show as a continuous pad or cushion, on one side mainly or extending across continuously on both sides, and from the breast to between the thighs. It usually pits on pressure, and may shed the hair and become rough and scabby or ooze a serous fluid from the surface.

On the limbs the swelling usually shows first on the fetlock or pastern and gradually extends upward until it reaches the body.

As the disease advances chaps, cracks and fissures tend to form on the swellings, showing about the head, on the lips or on the nose and maxilla where the noseband of the halter crosses; on the lower part of the body where the circingle crosses, or where the part is pressed upon in lying down, and in the limbs in the flexure of the joints—behind the pastern, or knee or in front of the hock. In many cases the skin and connective tissue sloughs, and drops off exposing the muscles, the tendons or the ligaments of the joints. In other cases the tendons are involved in the degenerative process or necrosis and become detached from their lower insertions so that the toe may be turned up or the fetlock pad may come to the ground. The matrix of the hoof wall (coronary band) may separate from the horn, leaving a gaping opening which exudes liquid freely, and if the animal survives, the entire hoof may be shed.

In other cases, and often quite early in the disease, the swellings may suddenly subside and disappear, with it may be, a recovery, or, in other cases, with an exudation into the lungs or chest, the digestive organs or abdomen. In case the lungs are attacked, there is hurried oppressed breathing merging into dyspnœa or asphyxia. In case the bowels suffer there are colicy pains more or less acute, with much constitutional disturbance, marked prostration and serous or bloody diarrhœa. These mostly prove speedily fatal. Less redoubtable are those cases in which the swellings alternately subside or moderate, and reappear or increase, without implication of the internal organs. The absence of internal lesions and the moderation and intermissions, of the external ones, give good hope of the preservation of the vitality of the tissues and of recovery.

Course and Duration. These vary much with the severity of the case. In subacute and tardy cases with few petechiæ and restricted swelling in the limbs, the symptoms become remittent and recovery finally takes place after one or two months. In other cases the morbid phenomena which developed rapidly may subside as quickly and recovery occurs in a few days. In the more typical case the visible lesions may encrease or remain stationary for one, two or three weeks and then terminate in death or recovery. In the most violent types death may occur within forty-eight hours. The average duration of the affection is found to be about 16 days.

Differential Diagnosis. In typical cases of petechial fever, diagnosis is easy. The supervention on a protracted or debilitating disease of the respiratory passages of an access of hyperthermia, and marked prostration, with the appearance on the nasal or other mucosa of petechiæ and swellings of a dark red color throughout, and of cutaneous swellings in the form of nodular elevations and more extended salient patches, having a tendency to ooze blood or serum, to crack and fissure is virtually pathognomonic.

Acute glanders may resemble it but lacks the extended sloughs of petechial fever, and the nasal ulcers that form in glanders are on a yellowish base and periphery, whereas the purpura ulcer is on an uniformly dark red base, and without the elevated margin seen in glanders. In cases of doubt the mallein test is not available as the purpuric patient is already fevered, or liable to be so at any moment, and any wound in such a subject will give rise to extensive swelling.

In glanders the nodular submaxillary enlargement is almost pathognomonic and still more so if the facial lymphatic vessels are thickened (corded) and both symptoms fail in purpura. In cutaneous glanders with swollen joints or limbs the attendant pain is much more severe, and the farcy buds, forming on the thickened and indurated lymph vessels, bursting and discharging an albuminoid fluid like oil have no counterpart in petechial fever. In cases of doubt the search for the glander bacillus, and above all the inoculation of a male Guinea pig in the flank and the discovery of the bacillus mallei in the resulting exudate and diseased testicle will decide.

From anthrax and emphysematous anthrax petechial fever is distinguished by the absence of the large bacilli of these respective diseases from the exudate. It is not communicable, like anthrax, to the sheep, Guinea pig and rabbit, and does not crackle on manipulation, like emphysematous anthrax. The swellings are much more generally diffused than in anthrax and the hyperthermia much less.

Urticaria furnishes a skin eruption which may be indistinguishable from the earlier skin lesions of petechial fever, but these lesions are not associated with the petechiæ in the nasal and other mucosæ, and the swellings do not advance to great sanguineous engorgements, cracks, fissures, necrosis, and deep and extensive sores as in purpura. Urticaria is, moreover, usually traceable to some digestive disturbance and fault in feeding.

Malignant œdema is usually confined to the seat of the inoculation wound and an extension around that, the exudate is very watery and may be mixed with fetid gas bubbles, so as to crepitate slightly, and it contains an abundance of its specific, round ended bacillus, often in chain form. The carcass putrefies with great rapidity.

Horse pox affecting the pastern and limb with attendant swelling is distinguished by the absence of petechiæ on the mucosæ, and by the formation on the affected part of little pea-like papules, which early exude an abundant liquid, the concretion of which on the hairs forms a remarkable yellowish encrustation, embedded in the angry red sores beneath.

Mortality. Prognosis. The mortality has generally averaged about 50 per cent. Much, however, depends on the violence of the attack, and the reduced and worn out condition of the patient. The most hopeful cases are those in which the temperature remains near the normal, the strength and appetite are well sustained, the swellings are comparatively slight, and there is no indication of any internal complication. The unpromising symptoms are: persistent high temperature; complete anorexia; great dulness and prostration; excessive swellings not only cutaneous but in the nose and throat as well; a marked oozing from the swellings with a tendency to form cracks, fissures and sloughs; the serious obstruction of breathing and prevention of hæmatosis by blocking of the nose, pharynx or larynx by sanguineous and serous exudate; the appearance of oppressed breathing and other indications of exudate with the lungs and chest, or of colics, diarrhœa, and other suggestions of effusion on the bowels or in the abdomen. Extreme fetor of the expired air and of the fæces is a bad symptom, though not always a fatal one. Sudden retrocession of the cutaneous swellings, may be the precursor of internal exudations and death, yet in the absence of marked acceleration of the pulse, and of the objective symptoms of disease of the chest or abdomen, it is rather to be taken as a herald of recovery.

Treatment. Whatever may be the precise cause of petechial fever it is largely connected with and maintained by an unhealthy condition of the blood, and especially with the presence of toxins and waste products in that liquid. The first consideration is to secure for the patient the best possible sanitary conditions. A roomy loose box, dry, clean, well lighted and well aired, nourishing, easily digested food—green food, carrots, turnips, or mashes—and pure water are desiderata. A sunny exposure is desirable especially in winter, and everything like chill should be guarded against. Blanketing may be called for in cold weather, but the circingle like the halter should be avoided as being calculated to cause indentation, cracking or sloughing of the swellings.

A moderate action of the bowels should be secured by the nature of the food (linseed meal or tea), or by small doses of saline laxatives (sodium sulphate) or calomel. Suppression of the urine too, must be counteracted by diuretics (saltpeter, oil of turpentine) when necessary.

Further internal medication has been aimed to correct the dilatation of the capillaries, and to prove antidotal to or to eliminate the poisons present in the blood.