Lung weight parallels disease severity in experimental coccidioidomycosis. (1/380)

Evidence provided by histopathological study of lesions is a valuable adjunct for evaluating chemotherapeutic efficacy in experimental animal models, In addition, this should be correlated with a measure of disease severity in the same animal. The latter could be obtained by homogenization of infected organs and quantitative enumeration of viable cells of the etiological agent, but this would preclude histopathological studies in the same animal. Progression of disease in pulmonary infection is associated with replacement of air space by fluid, cells, and cellular debris. Therefore, an increase in lung weight should reflect severity of disease. Results with the murine model of coccidioidomycosis demonstrate that increasing lung weight parallels the increasing census of fungus cells in the lungs of both treated and nontreated infected mice. This was supported with evidence obtained from microscopic studies of lesions indicating that specific chemotherapy limited spread of the infection and inhibited multiplication of the fungus in the lung. Therefore, lung weight can be used as a measure of disease severity in the murine model of coccidioidomycosis.  (+info)

MR imaging of acute coccidioidal meningitis. (2/380)

BACKGROUND AND PURPOSE: Our purpose was to describe the MR imaging findings in patients with acute coccidioidal meningitis. METHODS: Fourteen patients (11 men, three women; 22-78 years old; mean age, 47 years) with coccidioidal meningitis underwent neuroimaging within 2 months of diagnosis. Thirteen patients had MR imaging and one had an initial CT study with a follow-up MR examination 5 months later. Initial and follow-up MR images were evaluated for the presence of ventricular dilatation, signal abnormalities, enhancement characteristics, sites of involvement, and evidence of white matter or cortical infarction. The patterns of enhancement were characterized as focal or diffuse. Pathologic specimens were reviewed in two patients. RESULTS: Ten of the 14 images obtained at the time of initial diagnosis showed evidence of meningitis. All of the initially abnormal studies showed enhancement in the basal cisterns, sylvian fissures, or pericallosal region. Subsequent studies, which were available for three of the four patients with normal findings initially, all eventually became abnormal, with focal enhancement seen on the initial abnormal examination. Other abnormalities seen at presentation included ventricular dilatation (six patients) and deep infarcts (four patients). Pathologic specimens in two patients showed focal collections of the organism corresponding to the areas of intense enhancement on MR images. CONCLUSION: Early in its disease course, coccidioidal meningitis may show areas of focal enhancement in the basal cisterns, which may progress to diffuse disease. Pathologically, the areas of enhancement represent focal collections of the organism. Deep infarcts and communicating hydrocephalus are associated findings.  (+info)

Endemic mycoses: a treatment update. (3/380)

Endemic mycoses remain a major public health problem in several countries and they are becoming increasingly frequent with the spread of HIV infection. Amphotericin B remains the drug of choice during the acute stage of life-threatening endemic mycoses occurring in both immunocompetent and immunocompromised hosts. Ketoconazole is effective in non-AIDS patients with non-life-threatening histoplasmosis, blastomycosis, or paracoccidioidomycosis. Itraconazole is the treatment of choice for non-life-threatening Histoplasma capsulatum or Blastomyces dermatitidis infections occurring in immunocompetent individuals and is the most efficient secondary prophylaxis of histoplasmosis in AIDS patients. Itraconazole is also effective in lymphocutaneous and visceral sporotrichosis, in paracoccidioidomycosis, for Penicillum marneffei infection, and is an alternative to amphotericin B for Histoplasma duboisii infection. Coccidioidomycosis may be effectively treated with prolonged and sometimes life-long itraconazole or fluconazole therapy. Fluconazole has relatively poor efficacy against histoplasmosis, blastomycosis and sporotrichosis. New antifungal agents have been tested in vitro or in animal models and may soon be evaluated in clinical trials.  (+info)

Reactivation of coccidioidomycosis in a fit American visitor. (4/380)

The case history is presented of an American visitor, known to have had primary coccidioidomycosis previously, who became very unwell during a visit to the UK. Despite consideration of reactivation of coccidioidomycosis from the outset, other pathogens were identified while Coccidioides immitis was not initially, leading to a delay in treatment.  (+info)

The first imported case of pulmonary coccidioidomycosis in Korea. (5/380)

Coccidioidomycosis is an endemic disease found in the southwestern part of North America. Travellers who visit the endemic area may carry the infection. We report a case of pulmonary coccidioidomycosis in a 74-year-old woman. She was healthy before visiting Arizona, U.S.A twice. After returning home, she began to complain of intermittent dry coughing. The symptom was mild, however, and she was treated symptomatically. Later a chest radiograph, which was taken 4 years after the onset of the symptom, showed a solitary pulmonary nodule in the right upper lobe. By percutaneous needle aspiration, a few clusters of atypical cells were noted in the necrotic background. A right upper and middle lobectomy was done. A 1.5 x 1.5 x 1.2 cm sized tan nodule was present in otherwise normal lung parenchyma. Microscopically, the nodule consisted of aggregates of multiple solid granulomas inside of which was mostly necrotic. Neutrophils and nuclear debris were scattered along the periphery of the necrotic foci. Numerous multinucleated giant cells were associated with the granulomas. In the necrotic area, mature spherules of Coccidioides immitis, which were 30-100 microm in diameter, were present. They contained numerous endospores which ranged from 5 to 15 microm and were also noted in multinucleated giant cells. The diagnosis of coccidioidomycosis was made. She is doing well after the resection.  (+info)

Genes influencing resistance to Coccidioides immitis and the interleukin-10 response map to chromosomes 4 and 6 in mice. (6/380)

Coccidioidomycosis is a fungal infection that is endemic in the southwestern United States. Infection is more severe in blacks and Filipinos, which suggests that there is a genetic basis for susceptibility to this infection in humans. We found that there is also a difference in resistance to Coccidioides immitis infection among inbred mouse strains: B6 mice are susceptible, while DBA/2 mice are resistant (T. N. Kirkland and J. Fierer, Infect. Immun. 40:912-916, 1983). In this paper we report the results of our efforts to map the genes responsible for resistance to this infection in mice. Mice were infected by intraperitoneal inoculation, and 15 days later the numbers of viable fungi in their lungs and spleens were enumerated. We also determined the amounts of interleukin-10 mRNA made in the infected lungs. These three phenotypes were mapped as quantitative traits by using the 26 available lines of recombinant inbred mice derived from a cross between B6 and DBA/2 mice. The best associations were those between the regions near the Lv locus on chromosome 4 and the Tnfr1 locus on chromosome 6. We then infected backcross mice [(B6 x DBA/2) x B6] and confirmed these associations; 14 of 16 (87%) mice that were heterozygous at both Lv and Tnfr1 were resistant to infection, whereas only 4 of 16 (25%) mice that were homozygous B6 at both loci were resistant. These are the first genetic loci to be associated with susceptibility to C. immitis, but there may be additional genes involved in murine resistance to this infection.  (+info)

Resistance to Coccidioides immitis in mice after immunization with recombinant protein or a DNA vaccine of a proline-rich antigen. (7/380)

Two inbred strains of mice (BALB/c and C57BL/6) were vaccinated with either recombinant expression protein of a Coccidioides immitis spherule-derived proline-rich antigen (rPRA) in monophosphoryl lipid A-oil emulsion adjuvant or a DNA vaccine based on the same antigen. Four weeks after vaccination, mice were infected intraperitoneally with arthroconidia. By 2 weeks, groups of mice receiving saline or plasmids with no PRA insert exhibited significant weight loss, and quantitative CFUs in the lungs ranged from 5.9 to 6.4 log10. In contrast, groups of mice immunized with either rPRA or DNA vaccine had significantly smaller pulmonary fungal burdens, ranging from 3.0 to 4.5 log10 fewer CFUs. In vitro immunologic markers of lymphocyte proliferation and gamma interferon (IFN-gamma) release after splenocytes were stimulated with rPRA correlated with protection. Also, plasma concentrations of rPRA-specific total immunoglobulin G (IgG), IgG1, and IgG2a showed increases in vaccinated mice. These studies expand earlier work by demonstrating protection in mice which differ in H-2 background, by using an adjuvant that is potentially applicable to human use, and by achieving comparable protections with a DNA-based vaccine. Our in vitro results substantiate a Th1 response as evidenced by IFN-gamma release and increased IgG2a. However, IgG1 was also stimulated, suggesting some Th2 response as well. PRA is a promising vaccine candidate for prevention of coccidioidomycosis and warrants further investigation.  (+info)

Construction of a single-chain interleukin-12-expressing retroviral vector and its application in cytokine gene therapy against experimental coccidioidomycosis. (8/380)

T-cell-mediated immunity is an important determinant in protection against primary infection with Coccidioides immitis, a dimorphic fungal pathogen that causes the disease coccidioidomycosis. To determine if interleukin-12 (IL-12) gene therapy could potentiate host response against C. immitis, we constructed a single-chain cDNA encoding the p40 and p35 subunits linked by a polylinker and, using a retroviral vector, transfected J774 macrophages with the construct. The transduced J774 cells expressed IL-12 in vitro, with a mean concentration of 28,440 pg from 10(6) cells in 48 h as measured by an IL-12 (p75)-specific enzyme-linked immunosorbent assay. The secreted IL-12 was biologically active, as judged by its ability to induce the production of gamma interferon (IFN-gamma) by spleen cells from BALB/c mice. Treatment of the highly susceptible BALB/c mouse strain with the IL-12-transduced J774 cells inhibited C. immitis growth in tissues from mice challenged by a pulmonary route, as evidenced by 1.37-, 2.59-, and 1.22-log reductions in the number of CFU in the lungs, spleens, and livers, respectively, compared to the fungal load in mice given vector-transduced J774 cells. The protective effect of IL-12 gene therapy was accompanied by increased levels of IFN-gamma in the lungs and sera of mice treated with IL-12-transduced J774 cells and the constitutive production of IFN-gamma by their spleen cells cultured in vitro. These results suggest that IL-12 gene therapy could be used as adjunct therapy for coccidioidomycosis.  (+info)