Objective  To analyze the clinical characteristics of the recipients infected with cryptococcus neoformans after renal transplantation.

  Methods  Clinical data of 9 patients infected with cryptococcus neoformans after renal transplantation were retrospectively analyzed, including the infection site, clinical manifestations, mycological, histopathological, imaging examination results, treatment process and clinical prognosis.

  Results  Nine recipients were treated with routine triple immunosuppressive therapy of tacrolimus (FK506) + mycophenolate mofetil (MMF)+prednisone. The median time of onset was 6 years (1-13 years) after operation. Among them, 1 case was diagnosed with cryptococcal meningitis, 5 cases of cryptococcal meningitis complicated with cryptococcal pneumonia, 2 cases of cryptococcal pneumonia and 1 case of cutaneous cryptococcal infection. Cryptococcal pneumonia was clinically manifested as fever, cough, expectoration, shortness of breath and chest pain, etc. Chest CT demonstrated the signs of nodules and pleural effusion, etc. The diagnosis was mainly confirmed by lung biopsy and negative ink staining of the alveolar lavage fluid. Clinical manifestations of cryptococcal meningitis primarily included fever and paroxysmal headache accompanied by vomiting, which was mainly confirmed by blood culture and negative ink staining of the cerebrospinal fluid. Cutaneous cryptococcal infection was characterized by a mass in the right shoulder, which was confirmed by skin biopsy. All patients were given with standard antifungal therapy including amphotericin B and fluconazole, and immunosuppressive therapy at a reduced dosage. Among 9 recipients, 1 recipient died, and the other recipients obtained excellent clinical prognosis.

  Conclusions  Cryptococcus neoformans infection dominantly occurs in the middle and late stage after renal transplantation presenting with non-specific clinical symptoms. Blood culture, lung biopsy and cerebrospinal fluid examination should be timely performed to validate the diagnosis of this disease. Standard anti-fungal therapy can reduce the mortality rate.