Cases of Cryptococcus gattii outside the Pacific Northwest sparked a recent discussion among EIN members and a reminder that the Centers for Disease Control and Prevention (CDC) encourages the submission of isolates suspected to be C. gattii for identification.

A member in Florida described a patient who had never left Florida with disseminated C. gattii infection, confirmed by an outside reference lab by phenotypic methods. “He presented with pathologic fracture of the femur with soft tissue mass status post surgery with positive culture, and subsequent lumbar puncture demonstrated cerebrospinal fluid (CSF) loaded with Cryptococcus,” the member wrote. “The serum and CSF Cryptococcal Ag was 1:4096. Is this possibly the first case acquired outside of the northwest within the continental U.S.?”


Several respondents noted cases in other parts of the country, in patients with no contact with the Pacific Northwest, including in Los Angeles and Southern California, New York state, Florida, and Michigan. CDC subsequently confirmed the isolate and provided a genotype to the clinician.

A member in Maryland cited a Dec. 15, 2011, article and related editorial in Clinical Infectious Diseases. “There appear to be two things going on,” the member wrote: “1) True emergence of an outbreak in the Pacific Northwest caused by strains of the VGII type (a-c), and 2) Increased recognition of C. gattii disease in non-Pacific Northwest states, caused by multiple different molecular types (e.g., VGI in Hawaii, VGIII in S. California and other southwest states, and scattered cases of other VGI types in other states—Michigan, Rhode Island, and Georgia).”


The member added that there appear to be “‘hot spots’ of activity in specific regions,  especially in an area in Georgia, with multiple cases recently recognized, VGI types,” and recommended that an isolate from the original commenter’s patient be sent to CDC for typing—“my bet is that it’s going to be VGI. I actually think that these cases have been there for a while; we just haven’t been recognizing them to species level.”

Management of these cases “can be very different compared to neoformans, with some fluconazole resistance, especially in VGII isolates (with bad outcomes), and lots of inflammatory disease requiring shunting, steroids, etc.,” the member wrote.


A respondent from the CDC noted that although most C. gattii cases reported to CDC were initially from Pacific Northwest states, “and involved C. gattii strains specific to the outbreak (‘outbreak strains’ VGIIa, VGIIb, and VGIIc),” the interest generated from the outbreak led clinicians elsewhere to begin reporting cases, including many locally acquired C. gattii infections in other areas.

“To date, all except one of these infections have been caused by C. gattii strains different from the outbreak strains (mostly VGI and VGIII, or ‘non-outbreak strains’),” the CDC respondent continued, usually with quite different clinical presentation: “Namely, non-outbreak strain infections appear to more often cause severe meningitis in otherwise apparently healthy adults, whereas outbreak strain infections generally cause respiratory disease in persons with underlying diseases or conditions. The optimal clinical management may also differ.”



Some laboratories distinguish isolates of C. gattii from the related species C. neoformans, but many report all cryptococcal isolates as C. neoformans,” the CDC respondent wrote. “Additionally, antigen tests can’t distinguish C. gattii from C. neoformans,” suggesting  that “many C. gattii infections are likely misdiagnosed, with the treating clinician never realizing that their patient is infected with C. gattii.” (See related EIN Update from May 2012.)

 “CDC accepts isolates suspected to be C. gattii (Cryptococcus spp from HIV-uninfected persons) for molecular identification, and encourages their submission,” the respondent wrote. “We will provide timely feedback to the treating clinician.”


Isolates can be submitted to:


Shawn Lockhart, PhD, Team Lead
CDC

1600 Clifton Rd. NE

Attn: C. gattii surveillance

DASH Unit 40

Atlanta, GA 30333



Clinicians with questions can also contact Julie R. Harris, PhD, MPH, an epidemiologist in CDC’s Mycotic Diseases Branch, at ggt5@cdc.gov.

E-mail the Emerging Infections Network.

The Emerging Infections Network (EIN) is a provider-based sentinel network designed to help the public health community detect trends in emerging infectious diseases.

A joint project of IDSA and the Pediatric Infectious Diseases Society (PIDS) with funding from the Centers for Disease Control and Prevention (CDC), EIN tracks emerging infectious diseases and keeps the public health community up to date with new disease trends, difficult cases, and other issues affecting members’ clinical practices. The Network provides a great opportunity for members to share knowledge quickly across large geographical distances. Both IDSA and PIDS members are eligible to join. Click here for more information or to join EIN.

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