(Zoster; Zona; Ignis sacer; Shingles)
Definition. An acute inflammatory eruption, consisting of grouped vesicles situated on a red base, and distributed along the course of one or more cutaneous nerves.
Symptoms. Neuralgic pains usually precede the eruption for a few hours or days, but they may be coincident with the eruption or rarely may follow or continue after its decline. These pains may be limited to definite points or diffused about the region to be invaded and often sensitive points may be found along the course of the involved nerves. The eruption begins with some redness of the skin, followed in a short time by crops of irregularly grouped papules which are rapidly changed into pin-head to pea-sized vesicles, which follow in an interrupted manner the cutaneous course of the nerve or nerves involved. These vesicles may remain distinct and clearly outlined by the erythematous skin about them, or they may coalesce, forming bullae. Prickling, tingling or smarting sensations generally attend the development into vesicles. After remaining clear two to four days without tendency to rupture, the vesicles become opaque, dry into yellowish brown tendency to rupture, the vesicles become opaque, dry into yellowish brown crusts, and finally fall off, leaving a slight redness, or occasionally more or less persistent pigmentation at the seat of the lesions. such is the course of one group of the eruption, with an average duration of ten days. The eruption appears in successive crops, a few hours or days apart, and all the patches pass through the same course, so the duration of an attack may be prolonged to six weeks or even longer. Though the grouping is irregular and may vary from a half to six inches in diameter, the patches tend to form a semi- band-like distribution on one side of the trunk or on one extremity. The initial lesions may appear in the center or near the extremes of the area affected and tend to spread out and fill up the intervening space. Rarely they overstep the median line, and extend slightly beyond.
In all regions the distribution is almost invariably unilateral, although a few cases of bilateral zoster have been reported. I have seen one case of this rare type, giving a history of five previous bilateral attacks all in the cervical region. Although most cases of zoster follow a typical course, some lesions may become pustular, hemorrhagic (zoster hemorrhagicus), ruptured, ulcerated and exceptionally gangrenous (zoster gangremosus). These variations in the diseases result in consequent scarring and rarely kelodial growths. Occasionally in old people, zoster may assume a chronic tendency. On the other hand, the eruption of zoster may be arrested in the papular stage and a resolution occur without vesiculation (abortive zoster). Although the usual location of zoster is along the distribution of any cutaneous nerve of the trunk, commonly on the right side, many other cutaneous nerves may be affected, notably on the face, arms, legs or neck. In herpes zoster ophthalmicus, a severe destructive inflammation may occur in the cornea, iris, and occasionally in the entire eye. It is well to recollect that branches of several nerves connect with the same ganglion. Hence, if the latter is affected, the lesion may appear on any of the distal portions of the several nerve fibers. Single or combined names of anatomical regions have been employed to differentiate the localization of zoster, such as zoster frontalis, brachialis, pectoralis or intercostalis, curalis, genitalis, etc. Pain is usually a constant symptom, although it may be of any degree and any character, but usually disappears or is less noticeable after the onset of the eruption. Zoster, as a rule, occurs but once in a lifetime, though there have been a few notable exceptions. In one of my cases, there was a clear history of at least six recurrences; the first attack being observed by Hebra.
Ordinarily, zoster is a benign disease, ending in complete restoration of the structure and functions of the skin, except occasional scarring or abnormal sequelae in the form of sensory, trophic or motor disturbances, one alone or combined. The region affected may show diminished sensibility or complete anesthesia, hyperesthesia or paresthesia, Neuralgia is not infrequent, especially after facial zoster, but neuritis, fortunately, does not often occur. From a record of about 150 cases, I have noted only three in which neuritis followed zoster, one of these persisting for fifteen years. The function of the motor nerves in or near the region of zoster may be disturbed and very rarely present a temporary paralysis or muscular atrophy. Trophic effects that might be mentioned include the loss of teeth, hair and nails, and in two cases unilateral hyperhidrosis.
Etiology and Pathology. The disease is rare in infants, although I have recently seen a case in a child thirteen months of age. More than half of all the cases occur before the twentieth year of life, although it is not uncommon among adults in their prime. There has been some dispute as to the seasonal preference of this disease, although most statisticians claim that it occurs more frequently in the spring and autumn than at other times. This may be due, however, to the frequent variations of temperature at these periods since atmospheric changes have been noted as causal. Among other direct causes may be mentioned all varieties of traumatism, neoplasms, abscesses, pleurisy, inhalation of coal gas, administration of arsenic, tuberculosis, influenza, and in fact almost any local or internal condition that would cause an irritation of some nerve. Owing to clear evidence of direct contagion in a few cases, and the immunity from a second attack enjoyed by most patients, the belief is growing that zoster may, at least in some cases, be an infectious disease. Due to the action of toxins developed from numerous sources, its epidemicity is apparently well established in some instances.
Zoster is an irritation or inflammatory affection of some sensory nerve structure in any portion of its course from the periphery to the spinal center. There may be simple inflammation of the peripheral nerve, or there may be a distinct interstitial neuritis developed from an acute posterior poliomyelitis. When we remember that all spinal nerves are complex, and contain sensory, motor, vasomotor, and possibly independent trophic elements, it is remarkable that zoster pursues such a typical course, but this fact, not doubt, accounts for the differences of opinion as to whether it is a sensory, vasomotor, or trophic neurosis. The cutaneous changes are essentially the same as occur in other vesicular lesions. The one peculiarity of the zoster vesicle is found in its walls which contain epithelial cells transformed into round or ovoid bodies, which has been described by Unna as “ballooning” ad ‘reticulating colliquation.”
Diagnosis. The symptoms are so characteristic that it would seem hard to make a mistake in diagnosis. The vesicles of eczema are smaller, soon rupture, tend to produce a continuous discharge, and are attended with greater itching. The comparative difference from herpes simplex have been stated in the discussion of that disease.
Prognosis and Treatment. The former is most favorable, although successive croups may prolong the attack beyond the average duration of one to three weeks. In ophthalmic zoster, the possibility of resulting damage to the eye, in the hemorrhagic form, of scarring, or in the case of aged or debilitated people, a persistent neuritis, should be borne in mind.
The local treatment is purely protective, such as may be accomplished by applying any ordinary powder such as starch, talcum or zinc oxid on a layer or cotton or gauze held in place by a bandage. If there is much heat, stinging or burning, equal parts of alcohol and water may be laid over the lesions, on four or five thicknesses of gauze. If itching should ensue with the formation of crusts, 1 to 2 per cent. of carbolic acid may be added to the before mentioned prescription. When cellulitis or marked swelling is present, a 2 to 5 per cent. solution of creolin in glycerin may be used. For severe pain anodynes are occasionally necessary, but usually a solution consisting of one part of the tincture of hypericum to two parts each of alcohol and water will suffice. the high-frequency currents applied by means of the vacuum electrodes will relieve itching, promote absorption and often lessen the pain, and they are the most efficient means of combating a possibly resulting and continuing neuritis. Ordinarily, the treatment may be summed up in the terms of protection of the affected surface and the use of the indicated internal remedy. For the latter, see indications for Aconite, Arsenicum, Aster. rub., Belladonna, Cantharis, Cistus cir., Colchicum, Croton tig., Dulcamara, Graphites, Hypericum, Iris ver., Kali brom., Kalmia, Lachesis, Mez., Paris quad., Ranun. bulb., Rhus tox., Silicea, Spigelia.