Cases of pharnygitis with false membranes have been seen in horses by
Delafond, Targue, Rey, Bouley, Riss, Sonin, Robertson, Dieckerhoff and
Schneidemühl.
They have been attributed to various causes, as caustic alkalies and
acids, the smoke of a burning building (Bouley, Rey, Riss), to an
infection which operated on dogs and horses (Robertson), to bacteria and
other irritants.
_Lesions._ The mucous membrane of the mouth, pharynx and even the nares
presents active inflammation with branching redness, petechiæ,
circumscribed foci of necroses, and false membranes of a grayish,
yellowish, reddish, greenish or blackish color. These are formed of a
pellicle consisting mainly of fibrine and epithelium, pus globules and
numerous cocci, and ovoid bacteria. The false membranes have been found
on other parts of the intestinal canal (colon, cæcum); and
broncho-pneumonia and pulmonary dropsy have been concomitants. The
effect of the toxic products is seen in hæmorrhagic inflammation and
infarctions of the kidneys, and in a black color of the somewhat
diffluent blood.
_Symptoms._ Besides the usual phenomena of pharyngitis, there is intense
hyperthermia (105°–106°), hurried breathing threatening suffocation,
painful cough roused by the slightest pressure on the swollen throat and
often causing the discharge from the nose of shreds of false membrane.
Auscultation of the pharynx gives a loud gurgling sound. Deglutition is
very difficult and painful, liquids and even solids being rejected
through the nose. The face is pinched and anxious and the mouth is often
held open and the tongue pendant. Weakness and prostration are marked
symptoms from the first, and the walk may be unsteady and swaying. The
visible mucous membranes are congested and usually have a more or less
deep tinge of yellow. The disease makes rapid progress and may prove
fatal under six days. When it takes a favorable turn, recovery and
convalescence may be equally prompt.
Unless the expectoration of false membrane is detected, such cases are
difficult of diagnosis, though a fair inference may be deduced from the
extreme severity of the symptoms, and the unusual degree of prostration
which is present. When a pharyngeal speculum, passing through the nose,
can be availed of, it may become possible to reach a more definite
conclusion.
_Treatment._ Beside the measures advised for catarrhal pharyngitis
(poultice, counter-irritants, laxatives, antithermics, alkalies, etc.),
the main reliance must be placed on antiseptics. Persistent inhalations
of warm water vapor with carbolic acid, creolin, tar, lysol, camphor or
sulphurous acid are in order: also a mixture of one or other of these
agents or of boric acid, bisulphite of soda, or salicylic acid in honey
or molasses to be frequently smeared on the teeth. One of the best
agents is the saturated solution of chlorate of potash in tincture of
muriate of iron, of which a drachm may be added to three ounces of water
and given every hour or two. Calomel may be injected through the nose
during inspiration, by means of an insufflator, care being taken not to
exceed the physiological dose.