Cryptococcus gattiiInfections in Multiple States Outside the US Pacific Northwest

Abstract

Clonal VGII subtypes (outbreak strains) of Cryptococcus gattii have caused an outbreak in the US Pacific Northwest since 2004. Outbreak-associated infections occur equally in male and female patients (median age 56 years) and usually cause pulmonary disease in persons with underlying medical conditions. Since 2009, a total of 25 C. gattii infections, 23 (92%) caused by non–outbreak strain C. gattii, have been reported from 8 non–Pacific Northwest states. Sixteen (64%) patients were previously healthy, and 21 (84%) were male; median age was 43 years (range 15–83 years). Ten patients who provided information reported no past-year travel to areas where C. gattii is known to be endemic. Nineteen (76%) patients had central nervous system infections; 6 (24%) died. C. gattii infection in persons without exposure to known disease-endemic areas suggests possible endemicity in the United States outside the outbreak-affected region; these infections appear to differ in clinical and demographic characteristics from outbreak-associated C. gattii. Clinicians outside the outbreak-affected areas should be aware of locally acquired C. gattii infection and its varied signs and symptoms.

Cryptococcus gattii Infections

“…Single cases of infection have also been reported in the United States, including New England (85,243,247), New Mexico (272), and Florida (253); Europe (91,95,106,245); Asia, including Japan and Singapore (227,246,249); and South America (223,256). Most recently, Harris et al reported 25 cases, inclusive of previously described patients (247,253) diagnosed between 2009 and 2012, from Montana, Alabama, California, Hawaii, and Michigan; none of these patients had traveled to areas of C. gattii endemicity (251). In Australia, despite heightened awareness, no increase in the number cases has been observed (most large institutions care for 2 to 3 patients annually).…”

“…VGII infections also occur but are, to date, geographically restricted to the Arnhemland region of the Northern Territory and the southwest of Western Australia (113,117). In contrast, clonal VGII subtypes (referred to as outbreak strains) of C. gattii caused case clusters in British Columbia (subtypes VGIIa and VGIIb) and in the Pacific Northwest (subtypes VGIIa, VGIIb, and VGIIc) (38,132,198,251); subtype VGIIc is a novel subtype not found outside the United States (68). Theories on how these VGII subtypes may have arisen in North America are discussed above (see Epidemiology, Origin, and Evolution, above).…”

“…Theories on how these VGII subtypes may have arisen in North America are discussed above (see Epidemiology, Origin, and Evolution, above). Infection outside the Pacific Northwest has been caused by VGI and VGIII (242,243,251,272) as well as by subtype VGIIb and other, nonoutbreak subtypes of VGII (251).…”

“…On Vancouver Island, however, only 55% of the outbreak cases affected males, and in the Pacific Northwest, 54% affected males (132,198), suggesting that exposure is the predominant factor under these circumstances. Interestingly, 85% (21 of 25) of sporadic cases in the United States affected men (251). Population-based studies using uniform case definitions are needed to clarify whether there is a gender predisposition to C. gattii infection and, if so, whether there are additional genotype-dependent associations.…”

Cerebellar cryptococcoma due to Cryptococcus gattii VGI; a rare and first report from India

“…Posterior fossa mass lesions are rarely diagnosed as Cryptococcoma; hence reports on cerebellar cryptococcoma are limited. In the late stages, it may mimic brain abscess (Li et al, 2010;Harris et al, 2013).…”