As the most common pathogenic bacteria of trichosporidium asashii, trichosporidium asashii is the main pathogen of disseminated trichosporidiosis [6-7]. It is an opportunistic pathogenic fungus, accounting for 74% of the species of trichosporium .Currently, it is been considered that ascaris is a opportunistic pathogen that can affect the skin, lymph nodes, blood flow, craniocerebral, respiratory, liver and other systems[9-10].May have lung, skin, haematogenous and disseminated infections, such as pneumonia and endocarditis;In general, pathogenesis often occurs in patients with low immune function, tumors, combined with blood or organ transplantation, through hematogenous infection or systemic invasion, such as human immunodeficiency virus infection, duct-related infection, burns, artificial heart valve disease and peritoneal dialysis . Thus, current studies indicate that risk factors for infection include neutropenia, organ transplantation, diabetes, end-stage kidney disease, HIV infection, immunosuppressive agents, and the use of invasive medical devices.Catheter infection is a major source [12-13].In this group, 10 patients were cultured from the urine culture and underwent invasive surgery to preserve the catheter. The presence of catheter-related infection was the main source of trichoderma asahi. In particular, immunocompromised patients, such as cancer, blood diseases and AIDS, have a mortality rate of up to 80%.In this group, there were 1 patients with lung cancer, with a mortality rate of 30%.The major risk factors for the pathogenesis of trichosporium asahi include malignant tumors, cirrhosis, chronic renal insufficiency, granulocytosis, long-term use of ultra-broad-spectrum antibiotics and immunosuppressants, and damage to the skin and mucosal barrier . However, we found that there were 10 patients with old cerebral infarction in this group. Albumin was decreased in 9 cases, among which 4 cases were diagnosed with hypoproteinemia. So advanced age, cerebral infarction, hypoproteinemia may also be one of the risk factors.
Patients with neutropenia are more likely to cause infection, which is often fatal, with a fatality rate of 42% to 80%. Higher mortality may be associated with prolonged neutropenia, a high disease burden, delayed diagnosis, and inappropriate antifungal therapy [14-15]. However, in this group, the percentage of neutrophils increased in 7 cases, which was inconsistent with the report. It may be due to the high inflammatory index caused by acute infection and pneumonia. However, the percentage of eosinophil decreased in 7 patients in this group, possibly because eosinophil is closely related to the immune system by affecting the maturation of T cells and B cells and secreting a variety of cytokines to regulate the secondary immune reaction. Therefore, whether the decrease in the percentage of eosinophil can be used as an independent risk factor for the discovery of mucosporium asahi infection is open to question.
The determination of T cell subsets is an accurate method to determine cellular immune function . CD3+ cells reflect the maturation level of T cells in peripheral blood . CD4 + helper T cells, is a kind of has a proinflammatory role of cells, the main function is to produce antibodies and promote B cells differentiation, prompt T cells and other immune cells proliferation and differentiation, the coordination of the interaction between the immune cells, can also produce interleukin - 2, and so on the immune response to start the final expression form and play a key role on the strength, is a T cell subgroup with auxiliary and induced, it said the proliferation of B cells to produce the immune globulin increased and cell immune enhancement. CD8+ molecule is the early anti-infection cells, the main function is to kill the target antigen, can eliminate the pathogen, but the excessive number of cells can cause the body damage, it is one of the important causes of various immune dysfunction. CD8+ cells undergo apoptosis soon after killing target cells, showing unstable levels in peripheral blood . CD4+ and CD8+ subsets maintain a certain proportion when normal, interact with and antagonize each other functionally, and jointly maintain the functional balance of the body's immune system . The CD4+/CD8+ cell ratio is one of the important indicators to reflect the stability of immune system function, and its decline indicates the decline of human immune function . This indicates that the immune function of the patients is decreased in different degrees, which is also one of the causes of the infection of trichosporium asahi, consistent with the report.
Studies showed that voriconazole was the first choice for drug treatment of a. asasicum, followed by itraconazole and fluconazole [21-24], and drug resistance to carpofennet and amphotericin B [25-27]. Some reports suggest that there are regional differences in sensitivity to amphotericin B, with most drug resistance in foreign countries, but still sensitivity in mainland China [25,27]. Published in 2014, the European society of clinical microbiology and infectious diseases of medical mycology & Europe union (ESCMID&ECMM) launched the guidelines also recommend three azole antifungal drug therapy for invasive piedra, recommends voriconazole can be used as the preferred treatment , studies have shown that voriconazole can significantly inhibit the sassy MAO spore fungus infection . Liao yong et al. found that triazole antifungal drugs, especially voriconazole, can significantly improve the prognosis of patients, and it can be used as the first choice for the treatment of invasive trichosporidiosis, but its response to amphotericin B treatment is not good. In addition, studies have found that amphotericin B combined with fluconazole can also achieve a good therapeutic effect [5, 28]. Falk et al.  reported the multi-drug resistance of antifungal drugs such as fluconazole and itraconazole, which is sensitive to voriconazole. And after culture, the drug sensitive break point, found that the asashii trichosporium is highly sensitive to voriconazole, itraconazole sensitivity is the lowest. In addition, in this case, 1 patient had lung cancer complicated with the infection of trichosporidium asashii, which worsened with the progression of the disease and sustained fever. The application of a variety of antibiotics had no significant effect, but the antifungal treatment of voriconazole was effectively relieved, which was considered to be related to the infection of trichosporidium asashii.
The literature support
Based on the statistical analysis of data from PubMed, CnKI and Wanfang, the infection of Trichoderma asahi is more and more serious, and the mortality rate is also increasing gradually. Through analysis, lots of cases occur in Africa, Europe, North and South America, but the most in Asia. Also, male patients are more than female. Among the cases, the top three are hematopathy, diabetes, and lung infection. There are also patients with other diseases, such as cancer, organ transplants, AIDS. Blood infection is the most common, followed by urinary system, respiratory system and skin system. It’s found that neutropenia is the main feature of the disease. It is suggested that voriconazole, fluconazole and itraconazole are effective in treatment. Voriconazole was preferred, followed by fluconazole, amphotericin B and itraconazole.
Trichoderma asahi infection between China and other countries, it is found that among fungal infections, lung infection in Chinese patients is higher than that in other countries, while the number of patients with urinary tract infection in other countries is higher than that in China. For the mortality rate, China is lower than other countries.
Therefore, review of the literature found, although the number of cases in this paper is small, the analyzed clinical characteristics are roughly the same as those in domestic and foreign . The male patients were more than female patients.Among the cases of Trichoderma asahi infection,lung infection was the most common.In this case,It was also found that diseases such as advanced age, old cerebral infarction and hypoproteinemia were the main disease types of infection with Hirsutia asahi, and were mainly characterized by decreased percentage of eosinophils, low albumin and decreased CD4. The treatment was consistent with the literature review, which showed the highest sensitivity to Voriconazole in The treatment of Trichoderma asaxidium with good efficacy.