Fatal Primary Cutaneous Cryptococcosis

Abstract

Introduction Cryptococcus is a type of opportunistic encapsulated yeast with a worldwide distribution [1]. Cryptococcosis continues to cause significant morbidity and mortality, especially in immunocompromised patients such as those with AIDS, organ transplants, haematological malignancies, and corticosteroid treatment [2]. Primary cutaneous cryptococcosis (PCC), lesions associated with a skin portal of entry without systemic infection, is rare but life threatening [3]. Here, we report one case of rare fatal PCC in an immunosuppressed patient. The clinical diagnosis corroborated histological findings and causative agent was confirmed as Cryptococcus neoformans in culture isolate. Case Blog A 23-year-old man was admitted to our hospital with fever and swelling, painful lesions in both the anterior and the posterior of his trunk, with no history of cough, headache or vomiting. He received a massage half a month prior to admission. In his 20-month history of nephrotic syndrome, the patient was diagnosed with IgA nephropathy by renal biopsy and treated with prednisone (30-60 mg/d) for more than 1 year. Leflunomide and cyclophosphamide were each added once for a brief period. He had no known history of human immunodeficiency virus (HIV) infection and reported no contact with doves, poultry or other types of animals. On physical examinations, the patient had erythema, tenderness, edema and soft swelling skin lesions around the trunk. Cutaneous ulcers developed with time, with necrotic subcutaneous soft tissue and perilesional edema. The laboratory examination showed that peripheral white blood cell, CD4+ T cell count, CD8+ T cell count, CD20+ B cell count and the CD4+/CD8+ T cell ratio were 23.9(3.5-9.5) × 109/L, 143(651.3 ± 273.6)/μl, 236(452.62 ± 210.83)/μl, 159(125.22 ± 51.55)/ ul and 0.6, respectively, and that total blood immunoglobulin and immunoglobulin G were 17.9 (20-30) g/l and 4.8(7-16) g/l, respectively. The serum creatinine level was elevated at 1.86 mg/dl, and the cystatin C level increased to 2.50 mg/dl. Antibodies to HIV and to hepatitis B and C were all negative, and blood cultures were negative. The serum cryptococcal antigen latex agglutination test (Immuno-Mycologics, Inc., Norman, OK, USA) was positive at a titer of 1: 32. Chest computed tomography (CT) scan on Hospital Day 1 revealed signs of mild pulmonary infection without nodules. A cultural examination of necrotizing tissue on Sabourad glucose agar at 37°C for 3 days yielded cream-like colonies. The isolate was identified as C. neoformans by API 20C AUX (Biomerieux, Marcy, France). The antifungal susceptibility test showed that the fungus was sensitive to itraconazole but resistent to fluconazole. Skin biopsy revealed chronic inflammation with necrosis and numerous variably sized, round-to-oval budding organisms. Periodic acid-Schiff (PAS) staining of the dermis and soft tissue revealed blue, positive capsulated organisms (Figure 1) that were consistent with Cryptococcus. Cerebrospinal fluid examination, brain magnetic resonance imaging and abdominal ultrasound examination did not show any abnormaity. Fungal culture of the soft tissue revealed the growth of Cryptococcus and confirmed our clinical diagnosis of PCC. The patient was started on fluconazole (600 mg/d for 4 days) intravenously and then changed to itraconazole (500 mg/d for 5 days) intravenously according to the result of antifungal sensitivity test. Surgical debridement was performed every day (Figure 2). There was no evidence of disseminated intravascular coagulation. However, on the twenty-second day since admission, the patient died following continuous capillary haemorrhage