Treatment of recurrent disease

In treating recurrences of HSV infection, acyclovir and valacyclovir have all been found to be effective. Regardless of which one is used, these medications are more effective the earlier they are started. We recommend having patients get the prescription filled for the medication and keep it at home. They are instructed to begin taking the medication at the first tingling or other prodromal symptom they notice. Treatment regimens for recurrent HSV episodes for the various antiviral agents include the following:

Acyclovir 200 mg five times a day for 5 days

Acyclovir 400 mg three times a day for 5 days

Valacyclovir 500 mg twice daily for 5 days

In certain situations, one may wish to treat the patient prophylactically with antiviral therapy to prevent recurrences. Patients who are scheduled to undergo major cosmetic surgery on the face or extensive dental work should receive antiviral therapy in the doses used for recurrent HSV infections. Treatment should begin 2 days before the surgical procedure and continue for 5 days afterward.

Suppressive therapy should be considered in patients who develop frequent recurrences and patients who develop erythema multiforme after HSV recurrences. Patients may be started on chronic therapy with either acyclovir 400 mg twice daily or valacyclovir 1 g once daily. Once adequate suppression has been established, patients should be tapered to the minimal effective dose.

Topical Therapy

Topical antiviral agents such as Zovirax have been found to decrease the duration of outbreaks slightly. In patients who refuse more effective systemic therapy and patients who believe that topical therapy is effective, these agents may be prescribed safely. Zovirax is a cream that should be applied every six waking hours for 4 days.

Drying and disinfectant agents are used externally: 1-4 per cent silver nitrate solution, application of 1-2 per cent pyoktanin (gentian violet) solution, 30-50 per cent interferon ointment, Bonaphton, gossypol, tebrophenum, 1-3 per cent Florenal ointment.

Mouth gargle with astringent disinfectant solutions containing calendula, potassium permanganate, ethoxydiaminoacridine lactate or hydrogen peroxide is prescribed in herpes simplex of the mouth. A disseminated and frequently recurring process is treated by intramuscular injections of 2-3 ml of interferonogen given every six hours for three days. Favourable results are produced by intradermal injections of polyvalent antiherpes vaccine (0.1-0.2 ml is injected at intervals of two or three days; treatment consists of two courses of five injections made with an interval of 10 days). Gamma globulin injections, autohemotherapy, and pyrogenal are prescribed to prevent recurrences. Broad spectrum antibiotics are given when concomitant pyococcal infection develops.

Herpes zoster

Herpes zoster (HZ), also called shingles or zona, is caused by a neurotropic filterable varicella zoster virus (VZV). which resembles or is identical with the chickenpox virus in antigenic structure and the ability to grow in human embryonal tissues. The development of chickenpox in children who had been in contact with a patient suffering from herpes zoster confirms that these strains are related. Cases are known of adults who develop herpes zoster after contact with a child suffering from chickenpox. Lastly, there are cases in which the disease begins as typical herpes zoster and then transforms into chickenpox with the eruption spreading to the trunk and limbs.

Latent infection in nerve root ganglions follows an attack of chicken pox; reactivation of latent VZV infection leads to a blistering disease limited to a single or adjacent dermatomes. This self-limited disease often leads to severe pain in the affected region long after the lesions are healed. During an attack of chicken pox, the varicella-zoster virus travels along the sensory nerve fiber centripetally to the spinal and cranial sensory ganglia where the virus establishes a life-long latent infection.

On a later date, reactivation of the virus occurs in the ganglia where the virus is most numerous and is triggered by diminished immunity associated with advancing age, immunosuppression due to drugs or diseases like HIV infection or lymphoma, radiation or trauma.

Clinical picture. Herpes zoster affects both sexes equally. Occurrence is sporadic, without any seasonal variation. About 10-20% of people are expected to develop HZ in their lifetime. People of all ages may be affected. Frequency increases with advancing age. Two-thirds of patients are over forty years of age. Prodromal phase: is dominated by constitutional symptoms like headache, photophobia, fever, and pain. The pre-eruptive pain may be of varying severity and may be deep aching, sharp neuralgic or there may be allodynia (pain produced by minor stimuli like touching). The pain may mimic acute abdomen, migraine, or myocardial ischemia. The pain is soon followed by a rash limited to one side of the body in the distribution of a single or 2-3 adjacent dermatomes. Redness, papules and plaques appear, may be associated with itching or burning sensation.

After an incubation period (seven or eight days), the dermatosis is manifested by eruption of grouped vesicles on a hyperemic skin area corresponding to the segmental distribution of one or more nerves. The eruption is preceded by a prodromal period of attacks of pain along the distribution of the nerves, burning, hyperemia of the involved areas, general weakness, chill, and headache.

The erupted vesicles are tense, the size of a pea, and are filled with a clear serous content. They coalesce and form foci of affection with finely scalloped edges. The eruptions are characteristically asymmetric and unilateral. The following clinical varieties are distinguished: (1) generalized herpes zoster (herpes zoster generalisatus, disseminatus) marked by bilateral and disseminated lesions; (2) herpes zoster haemorrhagicus, in which the clear contents of the vesicles turn purulent and then, when the process penetrates deeper into the dermis, becomes hemorrhagic; (3) herpes zoster gangraenosus, a severe form, in which the floor of the vesicles undergoes necrosis and scars form in their place; (4) mild (abortive) form; (5) bullous form characterized by the appearance of both vesicles and bullae.

The lesions gets crusted and gradually heal over 2-4 weeks.

Thoracic segments are most commonly involved (>50%) followed by cervical, trigeminal, lumbosacral dermatomes. Mucosa in the affected dermatome are also involved. Viraemia occur during the course of the illness and a few outlying vesicles may be found elsewhere on the body away from the involved dermatome.

Tender, regional lymph node enlargement is common.

Stable neuralgia and muscular pareses may remain at the site of the affection after the acute skin manifestations disappear.

Localization of the process in the eyes (herpes zoster ophthalmicus) is a very dangerous condition, which sometimes terminates in ulceration of the cornea and panophthalmia. A severe form with involvement of the eyes is usually not encountered in children. Paresis of the trigeminal or facial nerve and loss of hearing are other grave complications. The disease may also be complicated by meningitis (herpes zoster meningitidem) and encephalitis. Infectious diseases, toxicosis, metabolic disorders, diseases of the blood, neuro-psychic overstress, cooling, and physical trauma promote the manifestation of the virus infection. The process usually occurs and exacerbates in the cold season (spring and autumn). Herpes zoster is encountered at any age, with the exception of very young children, among whom it is rare occurrence.

Elderly and old patients with herpes zoster following an atypical recurrent course must be examined so as to rule out a malignant new growth and a disease of the blood. Herpes zoster may sometimes precede some forms of hemoderma.

Complications: Post-herpetic neuralgia (PHN) is the dominant cause of morbidity in HZ. This is defined as pain persisting after 30 days of onset of rash. The incidence of PHN increases with advancing age. About 75% of patients above 70 years of age may develop this. PHN is limited to the site of the rash and can be extremely disabling, persisting for months to years. The degree of pain is not related to the extent or severity of vesicles or inflammation.

Histopathology. Ballooning and reticular degeneration of the epidermal cells, intranuclear viral inclusions, and degenerative changes in the nerve fibres are demonstrated. Acute inflammatory polymorphonuclear infiltration predominantly of a lymphocyto-histiocytic character, oedema, and dilated blood and lymph vessels are found.

Diagnosis. Prodromal pain. The irradiating pain preceding and often accompanying the eruption and the linear arrangement of grouped vesicles over the segmental distribution of the involved nerves distinguish herpes zoster from herpes simplex and erysipelas.

Typical clinical features of grouped vesicles on an erythematous base in a dermatomal distribution is highly diagnostic.

Tzank smear (smear from base of ruptured vesicle stained with Giemsa) reveals multinucleated giant cells. Direct immunofluorescence of cellular material to detect viral antigen. Culture or PCR for viral DNA

Herpes zoster is a self-limiting disease. Complete, spontaneous recovery within 2 to 4 weeks is the rule. Some residual sensory change and post-inflammatory dyspigmentation, however, may remain in some.