Fungal Histopathology

Fungal histopathology is an important diagnostic method for deep fungal infections, and the identification of fungi in tissues marks the level of pathogenic diagnosis. Immunohistochemistry classifies fungi according to the antigenicity of the fungus. Corneal biopsy can be performed in patients with suspected fungal keratitis and negative corneal scraping. Cut corneal lesion tissue with a sharp blade, or drill the diseased tissue during penetrating keratoplasty, fix with 10% formaldehyde or 95% alcohol, embed wax, slice, stain (HE stain, PAS stain or sputum) Orange staining, etc.). Or fixed with 2.5% glutaraldehyde, and sliced ​​by electron microscopy to observe the ultrastructure of the fungus. Basic Information Specialist classification: growth and development check classification: biochemical examination Applicable gender: whether men and women apply fasting: not fasting Tips: Pay attention to personal hygiene and avoid eating foods that are very irritating to the skin. Normal value The tissue suspected of having a fungal infection is cultured, and the examination method by microscopy or the like is performed, and the fungus is not detected as a normal condition. Clinical significance Abnormal results: Common actinomycetes causing eye infections are mainly Streptomyces, Nocardia, etc., causing keratitis, lacrimal ductitis, dacryocystitis, conjunctivitis, etc. Cryptococcus neoformans can be found in subacute or chronic meningitis or pulmonary infections, and can also invade the skin, subcutaneous tissue, muscles, lymph nodes and intestines. It can invade all organs and tissues when the lungs are disseminated by blood. Regardless of the type of cryptococcal infection that occurs, the central nervous system will eventually be infected. People who need to be examined: patients who have symptoms of fungal infections such as keratitis and lacrimal ductitis. Precautions Contraindications before inspection: Pay attention to personal hygiene and avoid eating foods that are very irritating to the skin. Requirements for inspection: 1. Inquire about the history of trauma and surgery, the time of injury, the location, the treatment after injury, the onset time, the development of the disease, and the history of vaccination against tetanus; for female patients, the history of childbirth or abortion should be consulted; For newborns, the history of childbirth and umbilical cord management should be asked. There were a few cases with no history of injury and no obvious wounds. 2, check the injured part, the wound situation, the muscles around the wound are sputum and twitching, paying special attention to whether the rectus abdominis is strong. If there is exudate or exfoliated tissue block in the wound, bacteriological examination (including smear and anaerobic culture) and pathological examination should be performed. 3, to observe whether the patient has closed teeth, paroxysmal convulsions, sneer, angulation, generalized tonic and paroxysmal spasm, pay special attention to whether the airway is smooth, with or without throat. After the patient is quiet, check for pulmonary complications and necessary auxiliary examinations. Inspection process Corneal biopsy can be performed in patients with suspected fungal keratitis and negative corneal scraping. Cut corneal lesion tissue with a sharp blade, or drill the diseased tissue during penetrating keratoplasty, fix with 10% formaldehyde or 95% alcohol, embed wax, slice, stain (HE stain, PAS stain or sputum) Orange staining, etc.). Or fixed with 2.5% glutaraldehyde, and sliced ​​by electron microscopy to observe the ultrastructure of the fungus. (1) Streptomyces (streptothrix) are slender and unbranched long hyphae, often broken into bacilli and sclerotium, gram-stained, bacilli-negative, cocci-positive. Giemsa staining can more clearly identify its morphology. The secretion of the lacrimal canal was white, gray-yellow clot, and the microscopic examination showed the bacteria and bacteria. Culture grows slowly. Often caused by lacrimal tubulitis, complicated by chronic conjunctivitis, dacryocystitis. (2) Nocardia is a group of aerobic actinomycetes widely distributed in the soil. Most are saprophytic non-pathogenic bacteria, of which the pathogenic effects of humans are N. novae and C. brasiliensis. The genus is filamentous and easily broken into bacilli and bacterium. The acid-fast staining showed a weak positive reaction, and the colonies were of different sizes on the common medium, and the surface was wrinkled or granular. Different species can produce different pigments such as yellow, orange red, red, and other colors. The eye often causes keratitis, dacryocystitis, lacrimal ductitis, conjunctivitis, endophthalmitis, and the like. Not suitable for the crowd Inappropriate crowd: not found yet. Adverse reactions and risks No related complications and hazards have been found.