Cryptococcus gattii Genotype VGIIa Infection in an Immunocompetent Japanese Patient: A Case Report and Mini-review

Autochthonous Cryptococcus gattii genotype VGIIb infection in a Japanese patient with anti-granulocyte-macrophage colony-stimulating factor antibodies

A 31-year-old Japanese man presented with cerebral and pulmonary cryptococcosis. Cryptococcus gattii (C. gattii) genotype VGIIb was detected in the patient's sputum and cerebrospinal fluid specimens. The serum levels of anti-granulocyte-macrophage colony-stimulating factor (GM-CSF) antibodies were elevated in this patient, which has been associated with pulmonary alveolar proteinosis and is considered a risk factor for C. gattii infection. After undergoing >12 months of antifungal treatments, the patient showed improvements in symptoms and findings on brain and lung imaging. Several Japanese patients who develop C. gattii infection have also been reported; however, most of these patients have been infected outside Japan, as C. gattii infection is rare in Japan. Only one patient with C. gattii genotype VGIIb infection has been reported in Japan, and it is believed that this patient contracted the infection in China. In the present case, our patient has never been outside Japan, indicating that the infection originated in Japan. Our findings suggest that C. gattii might be spreading in Japan. Therefore, patients with positive serum anti-GM-CSF antibodies should be thoroughly monitored for C. gattii infection, even those living in Japan.

Cryptococcus gattii: A Poseur to Behold!

Cryptococcosis is an invasive systemic mycosis caused by Cryptococcus, a genus of yeast. Causative organisms for human cryptococcosis include Cryptococcus neoformans and Cryptococcus gattii. Disease due to C.neoformans is conventionally seen in patients with underlying immunosuppression, whereas C.gattii-related infection is usually seen in immunocompetent people. The fact that the infection can occur among otherwise healthy individuals underscores the importance of having a necessary understanding of the pathophysiology and clinical and radiological presentations of the disease. We report a case of disseminated pulmonary and central nervous system (CNS) cryptococcosis in an apparently immunocompetent individual with unusual radiological findings necessitating probing for alternative diagnoses. We have attempted to supplement and revise the existing data on the radiological manifestations of C.gattii.

Treatment of Cryptococcus gattii Infection Using Voriconazole

We previously reported a 39-year-old man who presented with pulmonary and cerebral Cryptococcus gattii (genotype VGIIa) infection and was successfully treated with liposomal amphotericin B and flucytosine induction therapy. Following induction therapy, oral fluconazole treatment was initiated as consolidation therapy. However, the patient complained of progressively worsening headache, presenting an elevated cerebrospinal fluid (CSF) cell count. The minimum inhibitory concentrations of the CSF isolate were 8 and 0.12 μg/mL for fluconazole and voriconazole, respectively. The oral administration of voriconazole for more than 18 months alleviated his symptoms. Voriconazole might be useful for controlling refractory cases of C. gattii infection.

Cryptococcosis caused by cryptococcus gattii: 2 case reports and literature review

Cryptococcosis caused by Cryptococcus gattii, is a life threatening fungal infection with recently increasing prevalence. C. gattii is a species complex comprising multiple independent species. However, many biological characteristics and clinical features of cryptococcosis due to C. gattii are relatively less well defined. In this paper, we identify two cases of C. gattii infection, and laboratory findings of genotype VGI and VGII in two groups of apparently immunocompetent Chinese individuals respectively. Upon detailed review of all 35 cases of C. gattii infections, it was observed that C. gattii can cause debilitating illness in both immunocompetent and immunocompromised individuals. Cryptococcosis due to C. gattii is a serious systemic fungal infection, with pulmonary central nervous system tropism. Epidemiologically, C. gattii infection is not only restricted in tropical and subtropical regions, but also in other geographical settings.

Pulmonary cryptococcosis: A review of pathobiology and clinical aspects

Pulmonary cryptococcosis is an important opportunistic invasive mycosis in immunocompromised patients, but it is also increasingly seen in immunocompetent patients. The main human pathogens are Cryptococcus neoformans and C. gattii, which have a worldwide distribution. In contrast to cryptococcal meningitis, pulmonary cryptococcosis is still underdiagnosed because of limitations in diagnostic tools. It can mimic lung cancer, pulmonary tuberculosis, bacterial pneumonia, and other pulmonary mycoses both clinically and radiologically. Pulmonary nodules are the most common radiological feature, but these are not specific to pulmonary cryptococcosis. The sensitivity of culture of respiratory samples for Cryptococcus is poor and a positive result may also reflect colonisation. Cryptococcal antigen (CrAg) with lateral flow device is a fast and sensitive test and widely used on serum and cerebrospinal fluid, but sera from patients with pulmonary cryptococcosis are rarely positive in the absence of disseminated disease. Detection of CrAg from respiratory specimens might assist the diagnosis of pulmonary cryptococcosis but there are very few data. Molecular detection techniques such as multiplex reverse transcription polymerase chain reaction (RT-PCR) could also provide better sensitivity but these still require validation for respiratory specimens. The first line of treatment for pulmonary cryptococcosis is fluconazole, or amphotericin B and flucytosine for those with central nervous system involvement. Pulmonary cryptococcosis worsens the prognosis of cryptococcal meningitis. In this review, we summarize the biological aspects of Cryptococcus and provide an update on the diagnosis and management of pulmonary cryptococcosis.

Epidemiological, Clinical and Outcome Aspects of Patients with Cryptococcosis Caused by Cryptococcus gattii from a Non-endemic Area of Brazil

Cryptococcosis by Cryptococcus gattii occurs mainly in immunocompetent hosts, however, during the last decades, a growing number of cases in immunocompromised individuals have been noticed around the world. This report presents epidemiological, clinical and outcome aspects of patients with cryptococcosis caused by this species from a non-endemic area in Brazil. Of 278 Cryptococcus spp. clinical isolates recovered during the same period, 267 (96%) were molecularly identified as Cryptococcus neoformans VNI genotype and 11 (4%) as C. gattii VGII genotype by URA-5 RFLP. Of the 11 C. gattii patients, eight were male, mean age of 47.5 years. Of these, four were HIV-infected, one was kidney transplanted, one presented low CD4⁺ T cells values of unknown cause, another presented chronic liver disease meanwhile the remaining four were apparently immunocompetent. Disseminated disease and cryptococcal meningitis were present in four patients each. Most patients received amphotericin B plus fluconazole. Seven out of the 11 patients cured and four died before or during the therapy. The increased number of individuals with cryptococcosis by this species during the last decades needs to be carefully evaluated specially those who are HIV-infected. Nevertheless, Cryptococcus species differentiation is currently relevant in order to better know their relation with geographical, clinical host preference and outcome particularities.

Pulmonary cryptococcosis coexisting with adenocarcinoma: a case report and review of the literature

Background

Pulmonary cryptococcosis is a common fungal infection frequently seen in immunocompromised patients. Owing to its nonspecific clinical and radiographic features, the differential diagnosis with secondary tuberculosis, malignant tumor, and bacterial pneumonia is sometimes difficult. Many case reports have focused on misdiagnosis of pulmonary cryptococcosis as a malignant tumor. But to the best of our knowledge, the coexistence of pulmonary cryptococcosis and malignant tumor is rarely presented.

Case presentation

A 52-year-old immunocompetent Han Chinese woman was presented to our emergency department complaining of headache and vomiting accompanied by postural changes. She was diagnosed with pulmonary cryptococcosis according to results of laboratory tests, computed tomography, and percutaneous lung biopsy. Owing to the poor therapeutic effects of 6-month fluconazole treatment, she underwent a second percutaneous lung biopsy and was diagnosed with pulmonary cryptococcosis coexisting with adenocarcinoma. Delayed treatment of malignant tumor resulted in lymph node metastasis, higher pathologic stage, and probably poorer prognosis.

Conclusions

Our patient’s case serves as a reminder not to misdiagnose pulmonary cryptococcosis coexisting with adenocarcinoma.

Cryptococcus gattii genotype VGIIa infection imported from Vancouver Island to Japan

A 71-year-old Japanese man with travel history to the Vancouver Island, Canada was diagnosed the pulmonary and central nervous system infections caused by Cryptococcus gattii genotype VGIIa. This is the first imported case of Cryptococcus gattii genotype VGIIa infection from endemic area of North America to Japan. He was recovery with no residual neurological dysfunction by early resection of brain mass and antifungal therapy. Early surgical resection of cerebellar cryptococcoma may shorten the length of induction therapy with antifungal drugs.