Trichosporon beigelii: a life-threatening pathogen in immunocompromised hosts

Abstract

Summary:Patients undergoing bone marrow transplantation are profoundly immunosuppressed as a result of their intensive myeloablative chemotherapy and are at high risk for opportunistic fungal infections mainly caused by Candida spp and Aspergillus spp. Trichosporon beigelii (T beigelii) has emerged as a life-threatening opportunistic pathogen in granulocytopenic and immunocompromised hosts and there is a marked increase in cases reported in the literature. Response to antifungal agents is poor, mortality is high and immunological recovery is the most important factor for a favorable outcome in patients with trichosporonosis. We present three cases of T. beigelii infection in patients undergoing allogeneic bone marrow transplantation in our center and we review cases described in the literature. Bone Marrow Transplantation (2000) 25, 745-749. Keywords: tricosporon beigelii; bone marrow transplantation; immunosuppression Trichosporon beigelii (T. beigelii) is a ubiquitous yeast which inhabits the soil, but may also be present in the human skin and respiratory tract as normal flora. 1 It is known to cause white piedra, an innocuous, superficial hair infection commonly found in tropical and subtropical regions; 2 the yeast occasionally produces superficial dermatologic infections in an immunocompetent host, but can cause fatal systemic mycosis in immunocompromised patients. Populations at risk are people with HIV infection, bone marrow and organ transplant recipients, patients with profound neutropenia, low birth weight and premature infants 3 and patients with foreign bodies (ie prosthetic heart valves or indwelling catheters). 4,5 In the literature rare cases of cysto-peritoneal shunt infection, peritonitis, chronic meningitis, stenosing esophagitis, endophthalmitis, arthritis, cholangitis and hepatitis caused by T. beigelii have been reported. 6-13 Two antigenic types (T. ashaii, T. mucoides) have been demonstrated to be the causative agents of summer-type hypersensitivity pneumonitis first described in Japan. 14 antifungal agents is conflicting in various reports and its in vitro sensitivities may not correlate with in vivo antifungal efficacy. 15,16 The infection is usually insidious and the diagnosis is difficult to make because of its close resemblance to Candida species in both clinical features and histopathologic findings. 17 Little is known of host defence mechanisms against this yeast besides that the number of neurophils at the early stage of infection of other host defence mechanisms such as TNF-alfa overproduction in the lung have been demonstrated to be important in the prognosis of trichosporonosis in a murine model study. 18 The results reported in the literature with disseminated T. beigelii infection in immunocompromised hosts are disappointing; the majority of patients have died despite antifungal therapy and a successful outcome after infection appears to be related primarily to the patient's immunological recovery. Patients and methods Case 1A 17-year-old boy received an allogeneic BMT from h...

Current Knowledge of Trichosporon spp. and Trichosporonosis

“…This yeast-like pathogen may cause deepseated, mucosa-associated, or superficial infections. Invasive trichosporonosis is documented mostly in patients with hematological malignancies and other medical conditions associated with immunosuppression, whereas superficial infections and allergic pneumonia are found predominantly in immunocompetent hosts (24,46,98,184). Table 2 summarizes the sources of infection, main associated conditions, and etiological agents that are involved with the most clinically relevant Trichosporon infections.…”

Multidrug-Resistant Trichosporon asahii Infection of Nongranulocytopenic Patients in Three Intensive Care Units

“…Trichosporon asahii (Trichosporon beigelii) has increasingly been described as an opportunistic pathogen involved in disseminated infections in patients with profound granulocytopenia (9,11,26). Less commonly reported risk factors associated with infections caused by this agent include treatment with immunosuppressive drugs, transplantation, AIDS, extensive burns, and the presence of implanted prosthetic devices (9,11,14,20,24,27,29).Trichosporon species were the most common non-Candida cause of fungemia at a national cancer institute (23). Disseminated Trichosporon infections in immunocompromised patients are frequently fatal, despite therapy with amphotericin B (AMB) (9,44,46).…”

Extra-Bone Marrow Sites of Haemopoeisis: Dihydroartemisinin Effects in Wistar Albino Rats

“…Some drugs have been shown to be able to protect blood cells from damage while other drugs have effectively managed cancer of the blood (Erer et al, 2000;Tuan et al, 1992;Limoli et al, 2003;Reiter et al, 1997;Vijayalaxmi et al, 1996;1999;Easton, 1974;Chun et al, 1991;Lyytikainen et al, 1996). The multiplicity of substances which arrect the blood cells or the bone marrow show that a therapeutic agent like dihydroartemisinin that controls a disease of the blood [malaria can have profound effects on the haemopoeitic system.…”