Trichosporon Surgical Wound Infection in a Renal Allograft Recipient Successfully Treated With Voriconazole

A 39-year-old chronic kidney disease patient underwent a preemptive renal transplantation in November 2009. His native kidney disease was unknown (biopsy performed in 2006 showed diffuse global sclerosis). He reached end stage in 2009 and after that he was worked up for transplantation. He was not a diabetic and did not have any other comorbidity. He did not receive any immunosuppression before renal transplantation. His wife donated the kidney. His immunosuppression included Basiliximab (two doses) for induction along with prednisolone, tacrolimus, and mycophenolate sodium for maintenance. He had a prolonged warm ischemia time because of difficulty in donor nephrectomy. After surgery, he had a slow recovery in renal function for which a graft biopsy was performed on 4th postoperative day. It showed acute tubular necrosis. Tacrolimus levels were found to be high (13 ng/mL), and hence the dose was reduced. Because renal recovery continued to be slow, a second renal biopsy was performed after a week, which showed cortical necrosis at the upper pole. Without any specific intervention, renal function slowly improved to attain a nadir creatinine of 1.4 mg/dL. Dose titration of tacrolimus and mycophenolate sodium was performed in this period with therapeutic drug monitoring. In the postoperative period, he had received ciprofloxacin as treatment for lower respiratory infection and there were no other infective episodes. After suture removal, he was found to have pus discharge from the surgical wound site. A pus swab for culture grew Trichosporon species. It was confirmed by a second culture. An ultrasonogram revealed a small subcutaneous collection. Surgeons considered exploration to be unnecessary and wanted daily dressings only. A small noncompressing lymphocele was also noted near the lower pole of the graft kidney. Imaging studies excluded involvement of other organs. He did not have neutropenia. Antifungal therapy in voriconazole was begun at standard doses (400 mg twice daily on day 1 followed by 200 mg twice daily). Tacrolimus dose was decreased based on new trough levels. Mycophenolate area under the curve was found to be high, and the dose was dropped. He showed response to the treatment with clearing of the discharge. The wound healed within 2 weeks and the subcutaneous collection resolved. Voriconazole was continued for 4 weeks and stopped. His renal function remains stable and the wound is healthy. DISCUSSION Trichosporon species infection is an extremely uncommon opportunistic fungal infection (1). Several species have been identified. Trichosporon cutaneum (also called Trichosporon beigelli), Trichosporon asteroides, Trichosporon ovoides, Trichosporon inkin, Trichosporon asahii, and Trichosporon mucoides are the usual pathogenic species. They are segregated into serotypes I, II, III, and I–III; serotypes I (T. cutaneum, T. mucoides) and II (Trichosporon asahii, T. asteroides, T. inkin, T. ovoides) include pathogenic species, whereas serotypes III and I–III are nonpathogenic (2–4). T. cutaneum and T. asteroides cause superficial cutaneous lesions. T. ovoides and T. inikin produce piedra (scalp and pubic, respectively). T. asahii and T. mucoides produce systemic trichosporonosis (4). Clinical manifestations in systemic disease include pulmonary disease, fungemia and sepsis, cutaneous lesions, renal and hepatosplenic dysfunction, endocarditis, and chorioretinitis (5). It tends to be disseminated in immunocompromised individuals (6). Asymptomatic Trichosporon funguria has been reported in renal transplant recipients (7). Sternal wound infection after cardiac surgery has been reported (8). Other infections because of Trichosporon that have been reported include peritonitis in a chronic ambulatory peritoneal dialysis patient, endocarditis, catheter infection, and lung abscess (9–12). Antifungals are useful in clearing Trichosporon. Amphotericin B and the various azoles have been found to be useful in eradicating Trichosporon. However, minimal inhibitory concentration of Amphotericin B is high and in vitro resistance has been shown (13). Fluconazole has similar problems (14). Fluconazole 800 mg+amphotericin B deoxycholate 0.8 to 1.0 mg/kg per day is a recommended regimen (5). Voriconazole has the best in vitro activity among the azole agents (15, 16). Itraconazole and posoconazole are other useful agents (17). Newer drugs such as echinocandins, caspofungin, anidulafungin, and FK463 are considered ineffective and their use in combination therapy is being studied (18–20). Colony stimulation factor can be used in those with disseminated disease and neutropenia (5). Surgical debridement may be carried out as well. Summary Our patient represents a rare case of surgical wound infection because of Trichosporon species in a renal allograft recipient, which has not been reported so far. No other specific risk factor was present other than immunosuppressive agents. Standard dose of voriconazole for 4 weeks was found to be effective in curing the condition and was well tolerated. The dose of tacrolimus has to be decreased while using voriconazole because the latter increases the level of the former. Madhivanan Sundaram1 Komapala Anandbabu1 Gopal Basu1 Antony Devasia2 Veerasamy Tamilarasi1 1Department of Nephrology Christian Medical College Vellore, India 2Department of Urology Christian Medical College Vellore, India