Varicella-zoster uveitis
Introduction
Introduction to chickenpox-zoster uveitis Varicella-zoster uveitis can be congenital or acquired, and its acute retinal necrosis syndrome has become an important blinding eye disease. Isolation and culture of varicella-zoster virus from infected tissues can confirm the diagnosis. Slit lamp examination can detect anterior uveal lesions, and fundus fluorescein angiography can detect retinal vasculitis and corresponding characteristic changes in retinal neovascularization. basic knowledge The proportion of illness: 0.2% of the probability of being over 40 years old Susceptible people: no special people Mode of infection: non-infectious Complications: narcolepsy
Cause
Varicella-zoster uveitis etiology
(1) Causes of the disease
Because the pathogen of herpes zoster is the same as the varicella virus, it is called varicella/herpes zoster virus (VZV), which are different manifestations of the same virus infection, one is chickenpox that occurs in children. This is a primary infection; the other occurs mostly in adults with herpes zoster. After the primary infection, the virus can lurk in the body's nerve cells, mainly in the sensory ganglia, because it is a neurotropic single. The spore virus is also a DNA virus. The latent virus can cause disease under the stimulation of certain incentives. Common causes are low systemic resistance, such as trauma, various infectious diseases, AIDS, application of immunosuppressive drugs, radiation therapy, fever. And the elderly and the weak.
(two) pathogenesis
In children, when varicella-zoster virus infects the upper respiratory mucosa and oropharynx mucosa, it causes asymptomatic primary viremia. After the virus spreads to the reticuloendothelial cells, it propagates in these cells, after which the virus Released to the blood, a second viremia occurs. At this time, the virus replicates in monocytes. Secondary viremia is often accompanied by prodromal symptoms such as fever, chills, headache, weakness, and later focal skin and mucous membranes. Damage, with the formation of specific cellular and humoral immunity, the virus is cleared from the blood, in which cellular immune responses, especially alpha-interferon, play an important role in limiting viral infection, in primary varicella-zoster virus infection When the virus reaches the corresponding ganglion through the sensory nerve from the lesion of the skin mucosa, the virus can also reach the ganglion through the blood, mainly in the ganglion, and in the ganglion, when the body's resistance is reduced, the varicella-zoster virus When activated, the virus can travel backwards along the sensory nerve to the corresponding skin, causing skin herpes in the sensory nerve fiber distribution area, although any skin area is Involved, but the trigeminal nerve distribution area (especially the first branch) and the thoracic ganglion distribution area (thorax 3 ~ waist 2) are the most frequently involved sites, and the reduction of specific immune response is an important factor in the activation of the virus. Hormones or other immunosuppressive drugs are a common cause of the reduction of immune response. Because human immunodeficiency virus infection can cause the immune function of the body to decrease, it is also one of the causes of viral activation.
Prevention
Varicella-zoster uvitis prevention
Active antiviral therapy plays an important role in preventing the progression of inflammation and reducing tissue damage. In patients with retinitis at one time, it is of special significance to prevent retinitis in the other eye, especially to prevent retinal necrosis.
Complication
Varicella-zoster hericitis complications Complications, narcolepsy
The main complications are acute neuritis and neuralgia after herpes. Acute optic neuritis is called typhoon in traditional Chinese medicine. Blindness refers to the appearance of the eye, the sharpness of the eye or the sharp decline of vision in both eyes, and even the blindness of severe cataract. Cytomegalovirus retinitis is a slowly progressive disease that occurs almost exclusively in patients with suppressed immune function. The patient's vitreous inflammatory response is mild, retinal arteritis is also very mild, and lesions can occur anywhere in the retina.
Symptom
Varicella-zoster herpes zoster symptoms Common symptoms Red hail retinal edema, herpes, herpes, neuropathic optic atrophy, scarring, neuralgia, pigmented lymphadenopathy, herpes
Congenital infection
(1) systemic manifestations: congenital varicella virus infection is rare, the mother has a high mortality rate of 5 days before delivery or 48 hours after birth, low birth weight, manifested as atrophic limb, scar skin disease, brain atrophy , lethargy, stunting, etc.
(2) Ocular manifestations: A small number of congenital VZV-infected patients can find small or large scattered choroidal retinitis, which can also be expressed as the center of white ridged gelatin, surrounded by black scars, optic atrophy, retinal vascular tortuosity Small eyeballs, cataracts and Horner syndrome can also occur.
2. Acquired infections occur mostly in the elderly and young people.
(1) systemic manifestations: before the onset, there is often local lymph node swelling and skin tingling or burning sensation, and may have mild general malaise, often with neuralgia, sometimes quite serious, skin damage first clustered small Rice granules to mung bean big pimples herpes quickly develop into blister, surrounded by red blush, these blister arranged along the peripheral nerves into a band, this disease is more common intercostal herpes zoster, along the side of the intercostal nerve from the back up and down Stretching; secondly occurs in the first branch of the trigeminal nerve in the head and face, often causing eye damage; waist and abdomen, limbs can also occur, the course of disease is generally 2 to 3 weeks, blister can gradually eliminate scarring, such as no secondary infection No trace left.
(2) External eye performance: Eye herpes zoster is acute, pain is obvious, herpes often on the forehead and face of the half, not over the midline of the nose, along the trigeminal eye branch including acne-like herpetic lesions of the eyelid and the gingival margin, All cases were unilateral and accompanied by enlarged ear or submandibular lymph nodes, often with non-specific mild conjunctivitis and keratitis, indicating that this is a nasal ciliary nerve involvement, corneal dysfunction, keratitis as a point-like small round Epithelial turbidity, even the herpes of the corneal epithelium can quickly become a shallow ulcer; can also be dendritic, but the shape is smaller than the herpes simplex and can be multiple, severe cases can occur substantial discoid keratitis, also Scleritis can occur.
(3) uveitis: severe keratitis often accompanied by transient iritis, in addition to vZV caused by uveitis have the following:
1 exudative iridocyclitis: more than 2 weeks after the appearance of rash, generally appear small KP; also often appear sheep fat KP, began to be grayish white, after 2 to 3 weeks, turned into a large brown, KP subsided Slower, even 2 to 3 years later can still exist, the characteristics of this disease, the anterior chamber flashes light, moderate amount of floating cells, occasionally anterior chamber empyema or hemorrhage, inflammation oozing extensively, can occur after the iris adhesion and Adhesion in the periphery, and intractable glaucoma, may be caused by trabecular mesh inflammation; also due to atrophy of the ciliary body caused by low intraocular pressure, and even eyeball atrophy.
2 localized inflammation: a herpes on the iris similar to that seen in the cornea or skin, called herpes iridis, which is a manifestation of limited vasodilation of the iris. This disease has three typical symptoms, namely acute Trigeminal neuralgia, limited iris damage and anterior chamber hemorrhage, bleeding often repeated and severe pain, inflammation began after several months, and finally the iris became thin and atrophy, leaving depigmentation spots of varying sizes.
3 Chorioretinitis: In the past, it was thought that inflammation in the posterior segment was rare. Now, it is suggested that VZV can occur in healthy people except for acute retinal necrosis (ARN). Other systemic diseases such as leukemia, lymphoma chemotherapy patients and AIDS have more The risk of posterior infection, this disease type is one of the main manifestations of posterior ocular lesions of AIDS opportunistic infection, may also be associated with anterior uveitis, fundus retinal edema, multiple or limited chorioretinitis, Yellow-white exudation, may be associated with retinal vasculitis and optic neuritis, vitreous opacity, late formation of round choroidal atrophy and optic atrophy.
4 total uveitis: severe cases can cause inflammation in the anterior and posterior segments.
Examine
Varicella-zoster herpitis check
Isolation and culture of varicella-zoster virus from infected tissues can confirm the diagnosis; smear cytology of herpes base specimens, found that multinucleated giant cells have important value for diagnosis; acute varicella-zoster virus antibody titer More than 3 times or more than the recovery period titer is helpful for diagnosis; polymerase chain reaction (PCR) detection of aqueous humor or vitreous specimens helps determine the type of virus.
Scrotal examination can detect anterior uveal lesions; fundus fluorescein angiography can detect retinal vasculitis, retinal neovascularization, and corresponding characteristic changes in optic discitis.
Diagnosis
Diagnosis and diagnosis of varicella-zoster herpesitis
Congenital varicella-zoster virus infection often has a history of maternal infection during pregnancy. When patients have typical nervous system and ocular manifestations, it is generally not difficult to make a diagnosis.
The anterior uveitis caused by varicella-zoster virus often occurs in the regression phase of herpes zoster, so the diagnosis is generally not difficult. Retinitis caused by varicella-zoster virus should be able to cause large and flat white retinal damage. Identification of diseases including herpes simplex retinitis, cytomegalovirus retinitis, toxoplasmosis retinal choroiditis, syphilitic retinitis, camouflage syndrome caused by intraocular lymphoma, and Behcet's disease Retinitis and retinal vasculitis.
Both herpes simplex virus and varicella-zoster virus can cause iridocyclitis, retinitis and acute retinal necrosis syndrome, which are difficult to distinguish according to the clinical manifestations of uveitis, especially Acute retinal necrosis syndrome has a great similarity in clinical manifestations, which brings certain difficulties to the diagnosis, but according to the medical history, the accompanying skin manifestations and laboratory tests can distinguish the two.
