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J H Rex

Publications and source records attributed to J H Rex.

96 records · Page 6Linked to original sources

Normal and deficient neutrophils can cooperate to damage Aspergillus fumigatus hyphae.

Using a metabolic test of hyphal viability, the interaction between neutrophils and Aspergillus hyphae was investigated over a broad range of hyphae-to-neutrophil ratios. Normal neutrophils were found to damage hyphae whereas neutrophils from patients with both chronic granulomatous disease (CGD) and myeloperoxidase (MPO) deficiency did not. Further, both azide and catalase + superoxide dismutase inhibited the ability of normal neutrophils to damage hyphae, suggesting that this damage is mediated by products of the respiratory burst and by the MPO-halide system. Also, mixtures of small numbers of normal neutrophils with larger numbers of CGD neutrophils (range, 1:5 to 1:15) damaged hyphae more efficiently than either population of cells alone. Further, mixtures of CGD and MPO-deficient neutrophils, neither of which alone could efficiently damage hyphae, were able to damage the hyphae almost as well as a comparable number of normal neutrophils. These data demonstrate that intact neutrophils can cooperate to synergistically damage Aspergillus hyphae, possibly by extracellular mixing of hydrogen peroxide and MPO.

Aspergillus fumigatus↗

Successful management of Histoplasma capsulatum infection of an abdominal aortic aneurysm.

A 65-year-old woman with disseminated histoplasmosis underwent resection of an atherosclerotic abdominal aortic aneurysm. Yeast forms of Histoplasma capsulatum were present in the aneurysm. Surgical resection and revascularization with a Dacron graft followed by systemic amphotericin B therapy and chronic ketoconazole suppressive therapy have resulted in a patient without symptoms 15 months postoperatively. It is important to be aware of the potential for artherosclerotic aortic aneurysm involvement by H. capsulatum.

Aged↗

Voriconazole versus a regimen of amphotericin B followed by fluconazole for candidaemia in non-neutropenic patients: a randomised non-inferiority trial.

BACKGROUND: Voriconazole has proven efficacy against invasive aspergillosis and oesophageal candidiasis. This multicentre, randomised, non-inferiority study compared voriconazole with a regimen of amphotericin B followed by fluconazole for the treatment of candidaemia in non-neutropenic patients. METHODS: Non-neutropenic patients with a positive blood culture for a species of candida and clinical evidence of infection were enrolled. Patients were randomly assigned, in a 2:1 ratio, either voriconazole (n=283) or amphotericin B followed by fluconazole (n=139). The primary efficacy analysis was based on clinical and mycological response 12 weeks after the end of treatment, assessed by an independent data-review committee unaware of treatment assignment. FINDINGS: Of 422 patients randomised, 370 were included in the modified intention-to-treat population. Voriconazole was non-inferior to amphotericin B/fluconazole in the primary efficacy analysis, with successful outcomes in 41% of patients in both treatment groups (95% CI for difference -10.6% to 10.6%). At the last evaluable assessment, outcome was successful in 162 (65%) patients assigned voriconazole and 87 (71%) assigned amphotericin B/fluconazole (p=0.25). Voriconazole cleared blood cultures as quickly as amphotericin B/fluconazole (median time to negative blood culture, 2.0 days). Treatment discontinuations due to all-cause adverse events were more frequent in the voriconazole group, although most discontinuations were due to non-drug-related events and there were significantly fewer serious adverse events and cases of renal toxicity than in the amphotericin B/fluconazole group. INTERPRETATION: Voriconazole was as effective as the regimen of amphotericin B followed by fluconazole in the treatment of candidaemia in non-neutropenic patients, and with fewer toxic effects. RELEVANCE TO PRACTICE: There are several options for treatment of candidaemia in non-neutropenic patients, including amphotericin B, fluconazole, voriconazole, and echinocandins. Voriconazole can be given both as initial intravenous treatment and as an oral stepdown agent.

APACHE↗

Cunninghamella bertholletiae infection associated with deferoxamine therapy.

Cunninghamella bertholletiae, an uncommon cause of human infection, has been reported with increasing frequency in recent years. C. bertholletiae belongs to the order Mucorales and produces infections similar to those produced by the other agents of mucormycosis. Infections with this group of organisms have typically been seen either in patients with diabetes mellitus or in those receiving chemotherapy. Recent reports of mucormycosis in dialysis patients receiving deferoxamine for iron or aluminum overload have raised the possibility that deferoxamine therapy is a risk factor for mucormycosis. A case of C. bertholletiae infection in a patient receiving deferoxamine for iron overload unrelated to hemodialysis was investigated in detail, and possible explanations for this patient's infection were assessed.

Deferoxamine↗

In vitro growth-inhibitory activity of pneumocandins L-733,560 and L-743,872 against putatively amphotericin B- and fluconazole-resistant Candida isolates: influence of assay conditions.

L-733,560 and L-743,872 are water-soluble pneumocandins with potent antifungal activity. By beginning with the NCCLS M27-T method and varying test format (microdilution vs macrodilution), time of reading (24 h vs 48 h), and test medium (RPMI 1640 vs Antibiotic Medium 3), we have demonstrated that the MICs for these compounds can be altered significantly: the microdilution format, reading after 24 h and use of Antibiotic Medium 3 all reduced the measured MIC. No cross-resistance was demonstrated with either fluconazole or amphotericin B.

Amphotericin B↗