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Background: To better understand clinical and epidemiologic patterns of blastomycosis, we report on a large series of blastomycosis in Indiana., Methods: All microbiologically and histopathologically confirmed cases of blastomycosis from four hospitals serving Central Indiana from 1985 to 2014 were identified. Available data were collected. Data on population estimates, annual precipitation, and construction in Indiana were evaluated for correlations with incidence rates of blastomycosis., Results: A total of 114 patients were identified. The mean age was 44.4 years; 27% had diabetes mellitus, and 16% were immunosuppressed. Most presented with pneumonia (90%); 48% had extrapulmonary disease (CNS involvement in 9%), and 15% developed ARDS. Cultures, cytopathology, and histopathology were positive in 86%, 27%, and 85% of the sample, respectively, and fungal antigen was positive in 76%. Amphotericin B was administered in 49%, and 87% received an azole. Total mortality was 12%. Immunosuppression (OR = 3.0), diabetes mellitus (OR = 2.9), and multilobar pneumonia (OR = 2.9) were associated with increased likelihood of ICU admission. There was a significant increase in incidence over time in Marion County. There was no correlation with amount of precipitation, but the rise in incidence coincided with a 2005 state initiative to expand Indiana's highway infrastructure., Conclusions: The incidence of blastomycosis in Central Indiana may be on the rise. Physicians in endemic areas should be aware of the potentially fulminant consequences of the disease.

We present a case of a 35 year-old male with Blastomyces dermatitidis meningitis as the primary presentation of blastomycosis infection, without evidence of involvement outside the CNS at time of discharge. We focus on the magnetic resonance imaging findings, with histopathologic correlation., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Objective: To describe the clinical and histopathologic findings of a unique case of isolated optic nerve Blastomyces dermatitidis infection and to summarize the ophthalmic blastomycosis literature., Design: Case report and systematic literature review., Methods: A 70-year-old healthy man experienced impaired vision in his left eye. Magnetic resonance imaging (MRI) showed an enhancing process of the left optic nerve sheath. Although vision initially improved with oral dexamethasone, visual acuity subsequently decreased from 20/25 to no light perception over 8 weeks. An optic nerve biopsy revealed blastomycosis. Because ophthalmic blastomycosis infections are unusual, the Cochrane Library, PubMed, OVID, and UpToDate databases were searched using the term blastomycosis with the limits English and humans. Articles that predated the databases were gathered from current references., Main Outcome Measures: Visual acuity of the left eye and MRI of the orbits and brain., Results: Histopathologic examination of the nerve specimen showed B. dermatitidis infection. Needle biopsy and culture results of a suspicious lung scar were positive for Blastomyces. The patient was treated with intravenous amphotericin B followed by oral itraconazole for 6 months. The left eye remained blind 23 months after the biopsy. Approximately 40 articles describing ophthalmic infection were found in the literature search., Conclusions: Ophthalmic blastomycosis infections can cause rapid, complete vision loss. Prompt treatment is required, but infections are uncommon and usually are misdiagnosed, often because of lack of biopsy results. Tissue must be biopsied, cultured, or both for a definitive diagnosis. Because virtually all blastomycosis cases begin in the lungs, a chest radiograph or computed tomographic scan should be obtained. Any questionable lung lesion should be biopsied to corroborate possible ophthalmic disease.

Study Objectives: To study the epidemiologic and clinical features of blastomycosis in northeast Tennessee., Design: Retrospective review of blastomycosis cases in the region from 1980 through 1995., Setting: Hospitals located in the Tri-Cities region of northeast Tennessee., Patients: Seventy-two patients with confirmed blastomycosis infection., Interventions: None., Results: During the 1980 to 1995 study period, we documented 72 cases of blastomycosis. The mean age was 52 years (range, 13 to 86 years), most were male (69.4%), and nine were immunocompromised. A possible environmental exposure was noted for 28 patients. Pulmonary involvement represented the most common site of infection (61 cases), but multiorgan involvement was common (17 cases). Most patients with pulmonary blastomycosis (66%) presented with a chronic illness, and radiologic findings usually revealed local consolidation or a mass-like lesion. Nine patients developed ARDS with an associated mortality rate of 89%, compared with a 10% mortality for non-ARDS pulmonary cases. Antifungal treatment regimens varied widely, with amphotericin B often used for sicker patients. An epidemiologic evaluation revealed that the mean yearly incidence rate for blastomycosis quadrupled between 1980 and 1987 (0.31 cases/ 100,000 population) and 1988 to 1995 (1.23 cases/100,000 population) (p=0.00001). Most new blastomycosis cases in the 1988 to 1995 period occurred in three counties in the region where significant new construction projects have been underway., Conclusion: Blastomycosis is endemic in northeast Tennessee and the number of cases is increasing, coinciding with major new construction in the region. Clinicians in the area must be alert to this condition.

Animal models of fungal and other infectious diseases often require that the number of organisms in tissue be quantified, traditionally by grinding organs, plating them on agar and counting colony forming units (CFU). This method is labor intensive, slow as some fungi require two weeks of culture and limited in reliability by poor plating efficiency. To circumvent these problems, we developed a flow cytometric method to quantify yeast. In vitro cultured Blastomyces dermatitidis, Cryptococcus neoformans, Candida albicans and Histoplasma capsulatum yeast were labelled with specific monoclonal or polyclonal antibodies to stain surface determinants or with Calcofluor to stain cell-wall chitin. A defined number of fluorescently labelled beads were added prior to acquisition by flow cytometry as a reference standard for quantitation. Beads were readily distinguished from yeast by forward scatter, side scatter and intensity of fluorescence. Cultured yeast were enumerated by both standard CFU determination and flow cytometry in a range of 10(2) to 10(7) cells. Only flow cytometry enabled discrimination of live and dead yeast by using appropriate fluorescent dyes. The flow cytometric method was applied to murine models of histoplasmosis and blastomycosis to quantify the burden of fungi in the lungs of infected mice. Labelling yeast with Calcofluor alone resulted in unacceptably high levels of nonspecific binding to mouse cell debris. In contrast, labelling H. capsulatum with a rabbit polyclonal antiserum and B. dermatitidis with a monoclonal antibody to the surface protein WI-1 permitted accurate quantitation. We conclude that this flow cytometry technique is rapid, efficient and reliable for quantifying the burden of infection in animal models of fungal disease. The technique also should lend itself to performing cytotoxicity assays that require discrimination of live and dead fungi, or phagocytosis assays that require discrimination of intracellular and extracellular organisms.

The case of a solitary cerebellar abscess in a 36-year-old Rwandese male is described. First it was considered to be tuberculosis, but at microscopal examination of the lesion after neurosurgical excision the true germ was found: Blastomyces dermatitidis. This solitary intracerebellar blastomycosis abscess is only the fifth case reported worldwide and the first in African medical annals.

Four patients with pulmonary blastomycosis are reported. Their bronchial washings, submitted for cytologic evaluation and stained by the standard Papanicolau technique, yielded the diagnosis, subsequently confirmed by cultural identification of the fungus. In three additional cases, retrospective evaluation of cytologic material also revealed the organism, even though the diagnostic significance was not appreciated originally. Since cytologic techniques are simple, readily available, and rapid, they can be helpful in differentiating pulmonary neoplasms from pulmonary blastomycosis, thus reducing the need for diagnostic thoracotomies.

Ocular tissues from 13 dogs with naturally-occurring blastomycosis were examined histologically. Choroiditis and separation of the sensory retina from its epithelium were the most prominent lesions, although all three coats of the eye were always involved. Severe panophthalmitis was associated with a marked exudative reaction within the ocular tissues. Whereas inflammation of the anterior ocular tissues was often intense, it was rarely associated with the presence of B. dermatitidis. Sequelae to the ocular inflammation included cataract, synechiae, rubeosis iridis, and closure of the drainage angle. The last of these resulted in glaucoma and resulting degeneration of the optic nerve.