ocular pseudohistoplasmosis syndrome
Introduction
Introduction to ocular cytoplasmic syndrome At present, the clinically known cytoplasmic cytoplasmic disease refers to a clear boundary lesion in the fundus without vitreous inflammation. The chorioretinal scar around the optic disc and the choroidal neovascularization (CNV) membrane in the macular area are accompanied by tissue cells. The bacteriocin skin test showed a series of clinical manifestations such as positive. basic knowledge The proportion of sickness: 0.0023% Susceptible people: no special people Mode of infection: non-infectious Complications: retinal detachment
Cause
Cause of ocular cytoplasmic syndrome
Bacterial infection (35%):
POHS is presumed to be associated with histiocytic infections, which are based on patients who have lived or have lived in the Ohio and Mississippi River basins and have positive cytoplasmic skin tests, but have not been able to separate them in typical lesions of POHS patients to date. The pathogens were also unable to culture the cytoplasmic bacteria. The histopathological examination was mainly the subretinal fibrosis and vascular proliferation. The pathogenesis was that the cytoplasmic bacteria in the systemic infection were accompanied by local infection of the choroid, and the local inflammation subsided. After the formation of atrophy, allergic reaction or other factors can promote the production of CNV at the atrophic plaque, destroy the Bruch membrane into the subretinal, and finally form a discoid fibrous vascular scar, in addition, infection can also affect the pigment epithelium and choroidal capillaries, resulting in serum Sexual or hemorrhagic retinal detachment can eventually form fibrous scars.
Environmental factors (35%):
The disease can be transmitted through the respiratory tract, skin, mucous membrane and gastrointestinal endoscopy. The excretions of the patients in the epidemic area and the feces of infected animals can be carried. When the pathogen invades the human body, the patient's resistance can be expressed as primary or disseminated. Sexual infection, the patient is more male, the child patient is easy to develop progressive, the laboratory staff can also be infected, the tissue cytoplasm enters the choroid, first enters the choroid, and then invades the outer layer of the retina, vitreous Generally no inflammatory reaction, the main feature of pathology is nodular granulomatous choroiditis, which may be a local tissue allergic reaction caused by pathogenic bacteria. The macular lesions are characterized by Bruch membrane rupture and neovascularization, so that blood components can be infiltrated. Leakage under the RPE or under the retina, or induce subretinal vascular membrane formation, this hemorrhagic macular degeneration is prone to fibrosis, the formation of discoid scars, advanced lesions, granulomatous inflammation can also invade the iris ciliary body.
Prevention
Prevention of ocular cytoplasmic syndrome
The hyphae type of this strain is highly infective, and laboratory workers should pay attention to prevention. In the bird cages, chicken nests, etc., there is often contamination of the bacteria. Prevention should be taken. People who are in the first epidemic area have poor immunity due to the body. Special attention should be paid.
Complication
Ocular plexus cytoplasmosis syndrome complications Complications
Endophthalmitis, adhesive corneal leukoplakia or corneal staphyloma, the lesion surface and conjunctival sac have yellow-green purulent secretions, and have a special odor. The anterior chamber may have yellowish white empyema, sometimes filled with the anterior chamber. Because the annular abscess area isolates the cornea from the corneal surrounding blood vessels, blocks the nutrient supply, and the Pseudomonas aeruginosa and inflammatory reaction cause the epithelial cells to release collagenase, the ulcer rapidly expands and deepens, and the whole cornea can be affected in about 1 day. The formation of a full corneal abscess, even affecting the sclera can lead to blindness.
Symptom
Symptoms of ocular tissue cytoplasmosis syndrome Common symptoms Eye redness Retinal hemorrhage Retinal detachment
POHS does not show inflammatory manifestations of the anterior chamber and vitreous, and it is difficult to see early disseminated choroiditis in the clinic because these yellow-gray small spotted lesions are usually scattered in the fundus, and the inflammation is mild and self-limiting. Does not cause symptoms, clinically common is the scar left after the inflammatory lesions, called histoplasma spots, typical tissue cytoplasmic plaque appears as a clear, slightly concave circular or oval The depigmented choroidal retinal atrophy is like a punched out of a loose-leaf paper. Due to the degree and depth of the lesion, some of the atrophic plaques also have pigmentation or pigmentation. It can also be expressed as a black dot with a depigmented halo outside. The size of the tissue cytoplasm is more than 1/4 to 3/4 disc diameter.
The number varies from several to several tens of, mostly 4-8, and the eyes are often randomly distributed in the fundus of the posterior pole to the equator. A few patients may have depigmentation streaks parallel to the serrated edge near the equator. In the streaks, the number of pigmented cytoplasmic plaques can be arranged in a single line, and there can be atrophy and pigment changes around the optic disc. 70% of patients can be affected by both eyes. CNV in the macular area can cause subretinal hemorrhage, exudation and lipid deposition. It is often the main cause of vision loss. CNV is mostly gray-green under the retina, with a frosted glass appearance. Some patients with CNV or hemorrhagic retinal detachment can form a fibrous vascular discoid scar in the later stage.
Examine
Examination of ocular cytoplasmic syndrome
1. Serological examination The latex agglutination test can be positive in the early stage of the disease. The immunodiffusion test can distinguish the activity and inactivity of the disease. The screening test can be used for suspicious patients to detect patients early, and the latex agglutination test is used. Or immunodiffusion test, fluorescein-labeled antibody staining (FA) and complement-binding assay can also be used for the same purpose. Confirmation test can be used for the diagnosis and prognosis of the disease. The complement-binding assay is used, and the complement-binding assay appears. The positive time is later than other tests. Generally, after 6 weeks or 6 weeks of onset, the titer is 1:32, but the titer of a few active patients can be only 1:8 or 1:6, so dynamic observation is required. If the patient's titer continues to rise during the examination, it shows that the disease develops. The complement binding test and the tissue cytoplasmin skin test can hardly miss the patient. The fluorescein-labeled antibody stain can also identify the pathogens in the culture specimen and histopathology. Very clinically valuable.
2. Directly check the blood, pus, sputum, skin mucosal damage scraping and lymph nodes, liver, spleen, bone marrow and other aspirate to make a smear, stained with GMS or PAS, oil Mirror can be seen 2 ~ 4mm size Oval round spores are mostly found in large mononuclear cells.
3. Fungal culture The capsular tissue cytoplasmic fungus is a biphasic fungus. The specimen is inoculated into the fungal phase at room temperature. The colony grows slowly and is white cotton-like. The microscopic examination has hyphae and special-shaped gear-like spores. Infectious, brain heart extract blood agar cultured at 37 ° C in yeast phase, yeast-like colony growth, microscopic examination of spores about 1 ~ 5m in diameter, oval, can sprout, after dyeing is very similar to the onion slice.
4. Histopathological examination of acute disseminated patients with lung, liver, spleen, bone marrow and lymph nodes, a large number of tissue cell infiltration, a large number of spores inside and outside the cell, non-acute cases with epithelioid cell granuloma formation, neutrophils , lymphocytes, plasma cells, macrophages and Langerhans giant cells can also contain spores, but the number is small, the size is not the same, most of the old lesions have tissue brain tumors, there are a small number of pathogenic bacteria, surrounded by fibrosis, HE staining showed that the intracellular spores were spherical and slightly basophilic. The peripheral halo was caused by retraction during staining and was not a true capsule. PSA and GMS stained clearly, showing round or oval yeast-like spores, 2~ 5m in diameter, there may be a single bud, the bud neck is thin, and there is no halo around.
Fundus fluorescein angiography: Only for the CNV causing visual symptoms, the morphology of neovascularization can be seen early in the angiography. The cytoplasmic plaque of the tissue appears as a sharply shaped wheel-like strong fluorescent spot or obscuring fluorescence according to the change of pigment. Indocyanine green angiography can produce multiple strong fluorescent spots in the posterior pole.
Diagnosis
Diagnosis and differentiation of ocular cytoplasmic syndrome
Clinically, it can be diagnosed according to the characteristics of the fundus of POHS and the positive cytoplasmin skin test, but it should be differentiated from other diseases with white spots on the fundus.
The fundus manifestations of multifocal choroiditis with total uveitis are very similar to those of POHS, but there are obvious anterior and vitreous inflammatory manifestations, often with physiological blind spots, and multifocal ERG examination shows persistent diffuse damage, shotgun Retinal choroiditis is more common in the elderly. It is a creamy lesion in the fundus. The lesion is non-pigmented but often accompanied by vitreous inflammatory cell infiltration. The acute posterior multifocal squamous pigment epithelial lesion is also common in young patients. The fundus atrophy can be formed, but the lesion is large and irregular in shape, and mainly located in the posterior pole. In the acute phase, the fluorescein angiography in the early stage is to mask fluorescence and the latter is strong fluorescence.
