Ramsey Hunt syndrome is a herpetic lesion of the facial cranial node with the development of ganglionitis. Clinical manifestations include general infectious symptoms, unilateral vesicular rash and pain in the auricle, paresis of the facial nerve. Hearing disorders, vestibular disorders are possible. The diagnosis is made on the basis of clinical data, the herpetic etiology is confirmed by ELISA, PCR, and an additional study of the immune status is carried out. The treatment is complex, consists of antiviral therapy, antiepileptic, sedative, vitamin, vascular pharmaceuticals.
General information
Isolated inflammation of the peripheral nerve ganglion in neurology is referred to by the term “ganglionitis”. Ganglionitis of the cranial node of herpetic etiology was named Ramsey Hunt syndrome in honor of the North American neurologist who first described it in 1907. Along with herpetic trigeminal neuralgia, Hunt’s syndrome refers to postherpetic prosopalgia (facial pain), which develops in 10-20% of cases of acute herpes zoster infection. The disease occurs at any age in people who have previously had chickenpox. The premorbid background is the state of immunodeficiency. Elderly people are more susceptible to the development of chronic pain syndrome after the acute manifestations subside.
Causes
The main etiofactor of the disease is herpesvirus infection. The causative agent is the herpes virus type 3 — varicella-zoster. The main ways of infection penetration into the body are contact and airborne. Polymorphism and antigenic variability of virions within a single clone cause various clinical forms of primary lesion: chickenpox, shingles. Another specific feature of herpesviruses is the ability to go into a latent state, which allows them to persist for a long time in the nerve ganglia in the form of latent-associated transcripts.
The activation of viruses occurs when the immunological defense mechanisms of the macroorganism are insufficient. Immunosuppressive therapy of oncopathology and autoimmune processes, long-term treatment with corticosteroids, chronic somatic diseases (chronic pyelonephritis, bronchitis, heart failure), endocrine disorders (diabetes mellitus, hypothyroidism), severe injuries become factors provoking immunodeficiency.
Pathogenesis
During primary infection, part of the varicella-zoster herpesviruses is not destroyed by the immune system, but penetrates through the perineural spaces into the cranial node of the facial nerve, where it remains latent for a long time. Against the background of immunosuppression, virus reactivation occurs, which is accompanied by the development of an inflammatory reaction. Ganglionitis causes dysfunction of the neurons of the cranial node responsible for taste sensitivity, sensory perception of the skin of the outer ear, the auditory canal, and the post-auricular region. The spread of inflammation to the motor fibers of the facial nerve trunk passing by the ganglion causes loss of motor function — paresis of facial muscles on the side of the lesion.
In the acute phase of the disease, mainly thick fibers of type A are affected, normally activating cells of the gelatin substance of the posterior horns of the spinal cord. The neurons of the substance have an inhibitory effect on the modulation of pain impulses. Thus, the lesion of A fibers entails a violation of the mechanism of pain formation at the spinal level, which underlies the preservation of persistent prosopalgia after acute zoster ganglionitis. Sustained pain syndrome is observed mainly in older patients, which is associated with a decrease in the thickness of nerve fibers due to natural aging.
Classification
Ramsey Hunt syndrome occurs in various clinical variants, including also a combined lesion of the facial and vestibular-cochlear nerves. Understanding the form of the disease, the stage of its clinical course is necessary when choosing therapeutic tactics. According to the clinical classification , there are four main forms of the syndrome:
- Hunt I — rashes in the area innervated by the cranial ganglion are not accompanied by neurological symptoms.
- Hunt II — herpetic rashes occur with paresis of the facial nerve.
- Hunt III — facial paresis and bubble rash are combined with hearing impairment.
- Hunt IV — vestibular disorders join the manifestations characteristic of Hunt III syndrome.
There are three clinical periods during the course of the disease:
- General infectious — characterized by general symptoms: weakness, lethargy, fever.
- Cutaneous — the period of the appearance of a typical herpetic rash.
- Neuropathic — characterized by the predominance of neuralgic pain syndrome.
Symptoms
A typical beginning is like a classic viral infection. The syndrome manifests itself as a general malaise, an increase in body temperature to subfebrile and febrile numbers, cephalgia, a feeling of weakness, general weakness. After 1-2 days, herpetic rashes appear on the skin of the auricle, the anterior 2/3 of the tongue, and the soft palate on the affected side. The elements of the rash are bubbles filled with transparent or hemorrhagic contents. There is muscle weakness in the affected half of the face, leading to its asymmetry. There is a distortion of the face to the healthy side, the nasolabial fold is smoothed on the side of ganglionitis, the corner of the mouth is lowered. Paresis rarely reaches great severity.
Prosopalgia occurs from the first days of the disease or a few days after the appearance of rashes. The pains are localized in the ear area, radiate to the back of the head, neck, periorbital zone. Hyperesthesia of the auditory canal and parotid region is revealed, which is replaced by hypesthesia. In some cases, sensory disturbances cover the entire half of the face. Involvement in the pathological process of the auditory part of the vestibular cochlear nerve leads to the development of hearing loss, the appearance of ringing in the ears. When the herpetic lesion spreads to the vestibular nerve, manifestations of vestibular ataxia are added to the clinical symptoms: dizziness, instability, horizontal nystagmus.
Over time, bubble rashes dry out, exfoliating crusts form. Prosopalgia becomes the main clinical symptom. Pain sensations are of a deep bursting, burning nature, accompanied by local autonomic dysfunction: swelling, lacrimation, injection of sclera vessels. Permanent moderate pain syndrome with periodic fluctuation of pain is possible. A typical feature of postherpetic neuropathy is the dependence of the severity of pain on the psychoemotional state of the patient, climatic conditions.
Complications
Ramsey Hunt syndrome is characterized by a predominantly favorable course. Complications occur during the chronization of prosopalgia. Chronic pain causes sleep disorders, emotional and psychological disorders. Patients become irritable, emotionally labile, the general mood background decreases. In the absence of proper treatment of prosopalgia and psychological support, neurotic manifestations may develop: depression, hypochondria, neurasthenia. Therapy-resistant pain syndrome leads to a persistent decrease in working capacity.
Diagnostics
The typical clinical picture of vesicular eruptions in combination with neuritis of the facial nerve allows a neurologist to easily establish a clinical diagnosis. Since the background of the development of Hunt syndrome is an immunosuppressive state, an immunologist’s consultation is necessary to diagnose and identify the causes of immunodeficiency. If neurotic disorders are detected, a consultation with a psychologist, a psychiatrist is indicated. The basis of the diagnostic search is:
- Neurological examination. It reveals a decrease in the muscular strength of the facial muscles of half of the face, elements of hyperpathy, depending on the duration of the disease — hyper / hypesthesia of the parotid region, the auditory canal. Vestibular ataxia is characterized by instability in the Romberg pose, which increases when turning the head, closing the eyes.
- Hearing research. It is indicated if the syndrome proceeds with hearing loss. Consultation of an otolaryngologist with audiometry makes it possible to determine the degree of hearing loss, to exclude other causes of its occurrence.
- Laboratory tests. In the first days of the disease, moderate leukocytosis and a slight acceleration of ESR are noted in the blood test. ELISA and PCR diagnostics of herpes zoster are performed, confirming the herpetic etiology of cranial ganglionitis.
- Immunological examination. Allows you to assess the state of the immune system. It includes a study of cellular immunity, the level of immunoglobulins. Often diagnoses secondary immunodeficiency.
Ramsey Hunt syndrome must be differentiated from trigeminal neuropathy, neuralgia of the lingopharyngeal nerve. Unlike Hunt’s syndrome, in these cases, otoalgic pains are provoked by a contraction of the masticatory muscles during conversation, eating. Trigeminal neuralgia is characterized by the presence of trigger points corresponding to the exit points of the branches of the trigeminal nerve on the face. It should be borne in mind that in some cases Hunt’s neuralgia may be accompanied by moderate soreness of these points.
Treatment
In the acute period, etiotropic antiviral therapy is mandatory. Valacyclovir hydrochloride, acyclovir is used, in severe cases, drugs are administered intravenously by drip. Immunotherapy with human immunoglobulin and thymus pharmaceuticals is indicated for immunodeficiency. In the neuropathic period, complex treatment of prosopalgia is carried out, including:
- Anticonvulsants: carbamazepine, gabapentin. The effect of anticonvulsants is based on reducing the excitability of nerve fibers, inhibiting the spread of pain impulse through them
- Sedatives. Antidepressants (amitriptyline) are the most effective, neuroleptics (thioridazine, chlorprotixen), tranquilizers (diazepam) may be prescribed.
- B vitamins: thiamine, pyridoxine. They favorably affect the trophism of nervous tissue, contribute to the normalization of the conductive function of nerve fibers.
- Drugs to improve microcirculation (pentoxifylline, nicotinic acid). Stimulate the blood supply to the nerve trunk, which improves its nutrition, promotes the restoration of normal functioning.
- Anticholinesterase agents (neostigmine). They are necessary in the presence of prosoparesis. Potentiate the restoration of the strength of facial muscles by improving neuromuscular transmission.
- Physical therapy. Laser and magnetotherapy reduce the severity of inflammatory changes. Reflexotherapy is performed to eliminate pain and restore the motor function of facial muscles.
Prognosis and prevention
In most cases, with timely therapy, Ramsey Hunt syndrome has a favorable prognosis for recovery. Incomplete elimination of the virus during antiviral treatment causes individual relapses of the disease. Persistent course of prosopalgia is observed mainly in the elderly. Specific prevention consists in vaccinating children against chickenpox. An additional measure that can prevent Hunt’s syndrome is active antiviral treatment of patients with chickenpox. An important preventive value is a healthy lifestyle that allows you to maintain a high level of immunity.