Necrotizing fasciitis as the initial presentation of disseminated infection with fluconazole-resistant Cryptococcus neoformans

Cryptococcus neoformans, a global threat to human health

BACKGROUND

Emerging fungal pathogens pose important threats to global public health. The World Health Organization has responded to the rising threat of traditionally neglected fungal infections by developing a Fungal Priority Pathogens List (FPPL). Taking the highest-ranked fungal pathogen in the FPPL, Cryptococcus neoformans, as a paradigm, we review progress made over the past two decades on its global burden, its clinical manifestation and management of cryptococcal infection, and its antifungal resistance. The purpose of this review is to drive research efforts to improve future diagnoses, therapies, and interventions associated with fungal infections.

METHODS

We first reviewed trends in the global burden of HIV-associated cryptococcal infection, mainly based on a series of systematic studies. We next conducted scoping reviews in accordance with the guidelines described in the Preferred Reporting Items for Systematic Reviews and Meta-analyses extension for Scoping Reviews using PubMed and ScienceDirect with the keyword Cryptococcus neoformans to identify case reports of cryptococcal infections published since 2000. We then reviewed recent updates on the diagnosis and antifungal treatment of cryptococcal infections. Finally, we summarized knowledge regarding the resistance and tolerance of C. neoformans to approved antifungal drugs.

RESULTS

There has been a general reduction in the estimated global burden of HIV-associated cryptococcal meningitis since 2009, probably due to improvements in highly active antiretroviral therapies. However, cryptococcal meningitis still accounts for 19% of AIDS-related deaths annually. The incidences of CM in Europe and North America and the Latin America region have increased by approximately two-fold since 2009, while other regions showed either reduced or stable numbers of cases. Unfortunately, diagnostic and treatment options for cryptococcal infections are limited, and emerging antifungal resistance exacerbates the public health burden.

CONCLUSION

The rising threat of C. neoformans is compounded by accumulating evidence for its ability to infect immunocompetent individuals and the emergence of antifungal-resistant variants. Emphasis should be placed on further understanding the mechanisms of pathogenicity and of antifungal resistance and tolerance. The development of novel management strategies through the identification of new drug targets and the discovery and optimization of new and existing diagnostics and therapeutics are key to reducing the health burden.

Unilateral leg pain caused by cryptococcal myositis: An unusual presentation of disseminated cryptococcosis in a kidney transplant recipient

Cryptococcal disease is a rare but often serious infection in solid organ transplant recipients, commonly presenting as meningitis and pneumonia but can rarely cause myositis. We report the case of a 43-year-old female kidney transplant recipient with two previous graft failures requiring re-transplantations who presented with a 1-month duration of worsening unilateral leg pain, swelling, and shortness of breath. Blood cultures isolated Cryptococcus neoformans. A calf biopsy was performed and histopathology revealed myonecrosis with yeast forms consistent with Cryptococcus spp. Liposomal amphotericin B (LamB) was administered. Her course was complicated by hypoxemic respiratory failure with development of ground glass opacities on chest imaging. Work-up revealed bacterial and C neoformans pneumonia and probable Pneumocystis jirovecii pneumonia (PJP) She received trimethoprim-sulfamethoxazole and LamB and was discharged on fluconazole. Shortly thereafter she was re-admitted with confusion, septic shock, and multi-organ failure. Work-up revealed PJP with subsequent development of cryptococcal meningitis. Despite aggressive management, she expired. Disseminated cryptococcal infection may manifest as myositis. Presence of cryptococcal infection is a marker of severe net state of immunosuppression (IS), hence, presence of other opportunistic infections is likely. Early recognition of cryptococcal infection, institution of targeted therapy, and IS reduction are important to improve overall survival.