Trichosporidiosis
Introduction
Introduction to trichosporosis Trichosporonsis is a superficial and systemic infection caused by Trichosporon, which is more common in the tropics. Some temperate regions, especially in the southeastern United States, also have a high incidence, and white hair nodules are more common in young men, especially around the genitals. However, it does not seem to be contagious. Poor personal hygiene and low socioeconomic status are not risk factors for this disease. Systemic occurrence is similar to Cryptococcus. In fact, including a heterogeneous group, most of the trichomes can assimilate most carbon and nitrogen sources, making traditional nutrition experiments difficult to identify. Superficial infections, also known as white hair nodules, are white, brownish black or The green granular spindle-shaped nodules surround the hair shaft and are distributed irregularly. Sometimes nodules can be fused into clumps. Some patients with genetic traits can react with the antigens of Trichosporon to cause pneumonia. The clinical manifestations are superficial infection, allergic pneumonia, and invasive trichosporosis. Tissue culture, blood culture, and skin tissue pathology are very useful for diagnosis. basic knowledge The proportion of illness: 0.0003% Susceptible people: no special people Mode of infection: contact infection Complications: pneumonia
Cause
Cause of trichosporosis
(1) Causes of the disease
Trichosporon is classified as Mycoplasma, belonging to Basidiomycetes, and is phylogenetically similar to Cryptococcus. In fact, it includes a heterogeneous group. Most Trichospores can assimilate most carbon and nitrogen sources. To make traditional nutrition experiments difficult to identify, the ecological characteristics of Trichosporon can be found in the environment where parasites are parasitic in water and plants, and can also be separated from specific parts of the human body (digestive tract, respiratory tract, urinary tract and skin). Recently, through the morphology, xylose, ultrastructure, immunological characteristics, physiological and biochemical, coenzyme Q system, DNA-DNA hybridization and partial 26SrRNA sequence analysis were present in the cell wall, and the genus was reclassified into 17 strains and 5 Variants, of which there are 6 pathogenic bacteria:
1. Trichosporon ovoides, which can cause superficial fungal diseases, namely white hair nodules and skin lesions.
2. T. inkin, mainly isolated from the human groin area and anus, can cause white hair nodules of pubic hair, and two cases of systemic fungal diseases, endocarditis and peritonitis.
3. T.asahii (including three variants, namely var.asahii, var.coremiformis and var.faecalis), mostly isolated from patients with endogenous immunodeficiency, may also be isolated from the blood of hepatitis patients, or cause skin damage, There have also been reports of white hair nodules in mammals.
4. T. Asteroides can cause skin damage.
5. T. cutaneum causes skin damage and sarcoidosis and allergic response.
6. T. mucoides, mostly isolated from patients with endogenous immunodeficiency, can also be seen in pubic hairy white knot disease, and recently reported from the fungal disease, but there are still people still in Baijili Trichosporium represents all pathogens of this genus.
(two) pathogenesis
Superficial infection, also known as white hair nodules, is white, brownish black or green granular spindle-shaped nodules, surrounded by hair shafts and distributed irregularly, sometimes nodules can be fused into clumps, some have inheritance Patients with quality can react with the antigen of Trichosporon to cause pneumonia. Invasive trichosporosis is mainly seen in immunodeficiency patients. About 90% of patients see neutropenia, usually malignant hematological tumors, and skin damage is The third common lesion, which can reflect the spread of infection, is characterized by erythematous papules on the back and extremities, sometimes accompanied by blisters, and the papules gradually develop into central necrosis.
Prevention
Trichosporosis prevention
1. Develop good personal hygiene habits, do a bathing, and change underwear.
2. Reasonable nutrition, the disease can be induced by malnutrition, and patients who are treated with corticosteroids should pay attention to observe and prevent the disease.
Complication
Trichosporosis complications Complications pneumonia
Some patients with genetic qualities can react with the antigen of Trichosporon to cause pneumonia.
Symptom
Symptomosis symptoms common symptoms dyspnea meningitis nausea nodules peritonitis immunodeficiency papule hematuria
1. Superficial infection, also known as white hair nodules, is white, brownish black or green granular spindle-shaped nodules, surrounded by hair shafts and distributed irregularly, sometimes nodules can be fused into clumps, in fungal growth The hair shaft is brittle and easy to break. The knot on the hair shaft is soft and easy to wipe off the nodules from the hair shaft by hand.
2. Allergic pneumonia has been reported to be one of the causes of allergic pneumonia. Some patients with genetic quality can react with the antigen of Trichosporon to cause pneumonia, which can be reduced by removing the bacteria from the environment in which the patient lives. The incidence of this disease is currently not reported outside of Japan.
3. Invasive trichosporonosis is mainly seen in immunodeficiency patients, about 90% of patients see neutropenia, usually malignant hematological tumors, other risk factors include AIDS, severe burns, venous intubation, corticosteroid therapy And heart valve surgery, etc., mainly caused by Trichosporonus and Mucor.
Invasive infections can be divided into disseminated and limited, disseminated most common, manifested as acute fever, commonly used antibiotic treatment is not effective, infection often occurs quickly, leading to multiple organ failure and sepsis, lung and kidney are most often involved, Pulmonary involvement can cause dyspnea, cough, sputum, chest X-ray shows diffuse infiltration of alveolar, kidney involvement more than autopsy found, clinical manifestations of renal failure with microscopic hematuria and proteinuria, skin damage is the third Common lesions can reflect the spread of infection, manifested as erythematous papules on the back and extremities, sometimes accompanied by blisters, and the papules gradually develop into central necrosis. Some patients, such as improved cytopenia and effective antifungal therapy, can be converted into chronic The disseminated type is like chronic disseminated candidiasis, rare liver, spleen damage, manifested as fever and elevated serum alkaline phosphatase.
Infection can be limited to a single organ, including heart valves, central nervous system, peritoneal and surgical wounds. Most endocarditis is caused by prosthetic valves, but also by injecting drugs, usually as large and thick valvular sputum. Prone to embolism, especially in the lower limbs, the main symptoms of central nervous system infections include headache, nausea, vomiting and fever, more common in acute lymphoblastic leukemia, a case of meningitis caused by spinal radiography, chronic peritoneal dialysis caused by peritonitis Report.
Examine
Examination of trichosporosis
Blood, urine, sputum, cerebrospinal fluid and skin lesion tissue culture, blood culture is very useful for the diagnosis of disseminated infection, skin tissue pathology culture also has a suggestive effect, skin biopsy shows dermal invasion of mycelium and joint spores, some visible thrombotic veins Tube inflammation, should pay attention to the cultivation of Trichosporon from sputum and urine, may be colonization bacteria rather than infection, but for patients with neutropenia, the bacteria should be taken seriously from any specimen and further evaluated .
Serological examination: Serological methods can be used to evaluate the cross-antigen of Trichosporon and Cryptococcus neoformans polysaccharides before the culture results are obtained.
Diagnosis
Diagnosis and identification of trichosporonosis
Serological examination: Before the culture results are obtained, serological methods can be used to evaluate that there is a cross-antigen between Trichosporon and Cryptococcus neoformans polysaccharides. When the central nervous system infection of Trichosporon is reported, the Cryptococcus neoformans antigen is positive, therefore, Suspected cases, cryptococcal antigen testing is beneficial.
Identification with cryptococcal infection. Cryptococcosis is a fungal infectious disease caused by Cryptococcus neoformans that can be affected by the meninges, brain, lungs, skin, central nervous system or other internal organs.
