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Background: It is unclear whether procalcitonin is an accurate predictor of bacterial infections in patients with renal impairment, although it is used as a biomarker for early diagnosis of sepsis. We determined the sensitivity, specificity, positive and negative predictive values, accuracy and best predictive value of procalcitonin for predicting bacterial infection in adult patients with severe renal impairment., Methods: Retrospective study at a single-center community teaching hospital involving 473 patients, ages 18-65, with Modification of Diet in Renal Disease eGFR ≤30 ml/min per 1.73 m(2), admitted between January 2009 and June 2012, with 660 independent hospital visits. A positive or negative culture (blood or identifiable focus of infection) was paired to the highest procalcitonin result performed 48 hours before or after collecting the culture., Results: The sensitivity and specificity to predict bacterial infection, using a procalcitonin level threshold of 0.5 ng/mL, was 0.80 and 0.35 respectively. When isolating for presence of bacteremia, the sensitivity and specificity were 0.89 and 0.35 respectively. An equation adjusting for optimum thresholds of procalcitonin levels for predicting bacterial infection at different levels of eGFR had a sensitivity and specificity of 0.55 and 0.80 respectively., Conclusions: Procalcitonin is not a reliably sensitive or specific predictor of bacterial infection in patients with renal impairment when using a single threshold. Perhaps two thresholds should be employed, where below the lower threshold (i.e. 0.5 ng/mL) bacterial infection is unlikely with a sensitivity of 0.80, and above the higher threshold (i.e. 3.2 ng/mL) bacterial infection is very likely with a specificity of 0.75.

Schistosomiasis mansoni has been described as a predisposing factor for pyogenic liver abscess formation. Previous experimental studies have shown that acute schistosomiasis concurrent with Staphylococcus aureus bacteremia favors the colonization of the liver by the bacteria, and subsequent pyogenic liver abscess formation. In addition, clinical studies and case reports have demonstrated the association of schistosomiasis mansoni with pyogenic liver abscesses. We describe a Brazilian patient with chronic schistosomiasis mansoni who developed recurrent pyogenic liver abscesses due to Pseudomonas aeruginosa. The authors review the clinical, diagnostic and treatment aspects of patients with schistosomiasis and pyogenic liver abscess reported in the medical literature.

Zygomycosis, an uncommon but frequently fatal mycosis caused by fungi of the class Zygomycetes, develops most commonly as an opportunistic disease. Successful therapy involves a combined approach based on early diagnosis, prompt institution of medical therapy, and extensive surgical debridement of all devitalized tissue. Given the rarity of this condition, novel therapeutic strategies have been limited and only tested on an individual basis. The use of high-dose lipid formulations of amphotericin B, prompt reversal of the underlying predisposing condition, and hyperbaric oxygen are the most common strategies that have shown potential value in the treatment of zygomycosis.

We have yet to realize the clinical benefits of combination antifungal therapy, but the literature is beginning to show the potential positive and negative aspects of this approach. Detailed laboratory-based study of each new antifungal compound will be required in order to define the interactions between the different drugs. Most important in this discussion is that a determination of the most appropriate experimental design and parameters to reflect the outcomes in the treatment of human mycoses is required. That will be the challenge for the next several years. In the meantime, combination antifungal therapy should be approached carefully and be initiated on a case-by-case basis following consideration of all the options available for the patient.

We evaluated the efficacy of voriconazole, a new broad-spectrum triazole antifungal compound, in the treatment of murine pulmonary blastomycosis. Since mice metabolize voriconazole rapidly, we took advantage of our previous observation that administration of grapefruit juice to mice resulted in suitable serum voriconazole concentrations so that treatment studies with mice could be done (A. M. Sugar and X.-P. Liu, Med. Mycol. 38:209-121, 2000). Our results show that voriconazole prolonged survival in a dose-dependent fashion and that the fungal burden in the lungs was decreased by voriconazole administered at 40 mg/kg of body weight/day. Voriconazole should be studied in humans with blastomycosis.

Amphotericin B is the only recognized antifungal used in the treatment of mucormycosis. In this study, we evaluated various combinations of amphotericin B, fluconazole, and trovafloxacin or ciprofloxacin in the treatment of murine pulmonary mucormycosis. The combination of fluconazole and a quinolone has a marked effect on the outcome of murine pulmonary mucormycosis. Even though we did not optimize therapy with the drugs, these experiments suggest that azoles, especially fluconazole, in combination with either trovafloxacin or ciprofloxacin were effective in the treatment of this aggressive mycosis in the mouse model.

Fluconazole is currently a first-line agent used for therapy of non-critically ill patients with candidal infection. Its efficacy, the availability of an oral formula, and its relatively low toxicity make it a very attractive drug for use in many clinical situations. The advisability of prophylaxis and empirical treatment in transplant patients is a difficult issue for the following reasons: the potential emergence of resistance to the azoles, the lack of solid data establishing its advantage over placebo and/or oral nonabsorbable antifungal agents in some of the clinical conditions encountered, its ineffectiveness against molds, and its cost. Judicious use of fluconazole where its efficacy has been well established would provide the best therapy for patients and would limit the emergence of potential pathogens. As new antifungal agents are approved for clinical use, appropriate clinical trials will need to be designed and conducted in order for clinicians to make rational decisions in selecting the most appropriate drug for the specific indication. Prophylaxis and treatment with fluconazole in various transplant situations is reviewed.

Voriconazole is a broad spectrum, triazole antifungal drug now well into the final phases of clinical trials in humans. During preclinical phases of development, it was found that when administered to mice, one of the more important animals used in the in vivo evaluation of antifungal compounds, serum voriconazole concentrations were very low at best and often undetectable. This was due to a combination of high clearance and extensive metabolism by cytochrome P450 enzymes. As a result, mice were abandoned as being suitable for further study of voriconazole and most subsequent work with voriconazole has been performed in the guinea pig. In this study, we show that the administration of grapefruit juice, a known inhibitor of cytochrome P450 enzymes, is effective in producing measurable serum concentrations of voriconazole in mice when the drug is administered once daily. Serum voriconazole concentrations were < 3 microg ml(-1) at all time points in mice not receiving grapefruit juice. In contrast, grapefruit juice administered by once daily gavage or continuously in lieu of water in the water bottle resulted in serum voriconazole concentrations ranging 0.4-2.6 and 1.8-5.8 microg ml(-1), respectively, with increasing concentrations observed over the 10-day evaluation period. Further studies to elucidate the precise mechanism of action and optimal dosing schedule in mice can now be performed to improve our understanding of the pharmacokinetics of voriconazole in the mouse.

Although fungal urinary tract infections are an increasing nosocomial problem, the significance of funguria is still not clear. This multicenter prospective surveillance study of 861 patients was undertaken to define the epidemiology, management, and outcomes of funguria. Diabetes mellitus was present in 39% of patients, urinary tract abnormalities in 37.7%, and malignancy in 22.2%; only 10.9% had no underlying illnesses. Concomitant nonfungal infections were present in 85%, 90% had received antimicrobial agents, and 83.2% had urinary tract drainage devices. Candida albicans was found in 51.8% of patients and Candida glabrata in 15.6%. Microbiological and clinical outcomes were documented for 530 (61.6%) of the 861 patients. No specific therapy for funguria was given to 155 patients, and the yeast cleared from the urine of 117 (75.5%) of them. Of the 116 patients who had a catheter removed as the only treatment, the funguria cleared in 41 (35.3%). Antifungal therapy was given to 259 patients, eradicating funguria in 130 (50.2%). The rate of eradication with fluconazole was 45.5%, and with amphotericin B bladder irrigation it was 54.4%. Only 7 patients (1.3%) had documented candidemia. The mortality rate was 19.8%, reflecting the multiple serious underlying illnesses found in these patients with funguria.

To improve present results with antifungal drugs, modulation of the host immune response is being explored. Human phagocytes of various lineages work cooperatively in vitro with antifungal drugs to inhibit or kill fungal pathogens, and this activity is augmented by several recombinant cytokines. Monoclonal antibodies against the cryptococcal capsule have been shown to act as an adjunct in enhancing the outcome of cryptococcosis in animal models. This approach is now being pursued in systematic clinical trials. In experimental candidiasis, several manipulations of the immune system, via administration of cytokines, gene deletion or antibodies to cytokines, have been shown to significantly affect survival and fungal clearance in vivo. This approach has already been demonstrated to be of benefit with recombinant human granulocyte-colony stimulating factor adjunct therapy of human candidiasis. Combining antifungal drugs of different classes may enhance their therapeutic effect.

The antifungal activity of the nucleoside analog 3'-deoxyadenosine (cordycepin) was studied in a murine model of invasive candidiasis. When protected from deamination by either deoxycoformycin or coformycin, both of which are adenosine deaminase inhibitors, cordycepin exhibited potent antifungal efficacy, as demonstrated by prolongation of survival and a decrease in CFU in the kidneys of mice treated with cordycepin plus an adenosine deaminase inhibitor. The antifungal effect was seen with three different Candida isolates: Candida albicans 64, a relatively fluconazole-resistant clinical isolate of C. albicans (MIC, 16 micrograms/ml), and the fluconazole-resistant Candida krusei. Cordycepin and related compounds may provide another avenue for the discovery of clinically useful antifungal drugs.

The interactions of amphotericin B and itraconazole were studied in murine invasive candidiasis. Candida albicans-infected mice were treated for 10 consecutive days, 24 h after infection. Survival was monitored over 30 days and kidney cultures were done. Mice treated with amphotericin B (0.2 mg/kg/day intraperitoneally) or itraconazole (100 mg/kg/day by oral gavage in two divided doses/ day) had a 30-day survival of 20% or 40%. Concomitant administration of both drugs resulted in 100% mortality; 90% of mice treated with amphotericin B (1 mg/kg/day) survived. With the combination, 100% were dead by day 28 (P < or = .001 vs. amphotericin B). With sequential therapy (i.e., 5 days with one drug and then 5 days with the other), survival was inferior to that with amphotericin B alone but similar to that with itraconazole alone. Kidney culture results confirmed the antagonism of the combination compared with amphotericin B alone. In treatment of murine invasive candidiasis, the concomitant or sequential use of amphotericin B and itraconazole results in a negative interaction.

Catalase plays a key role as an antioxidant, protecting aerobic organisms from the toxic effects of hydrogen peroxide, and in some cases has been postulated to be a virulence factor. To help elucidate the function of catalase in Candida albicans, a single C. albicans-derived catalase gene, designated CAT1, was isolated and cloned. Degenerate PCR primers based on highly conserved areas of other fungal catalase genes were used to amplify a 411-bp product from genomic DNA of C. albicans ATCC 10261. By using this product as a probe, catalase clones were isolated from genomic libraries of C. albicans. Nucleotide sequence analysis revealed an open reading frame encoding a protein of 487 amino acid residues. Construction of a CAT1-deficient mutant was achieved by using the Ura-blaster technique for sequential disruption of multiple alleles by integrative transformation using URA3 as a selectable marker. Resulting mutants exhibited normal morphology and comparable growth rates of both yeast and mycelial forms. Enzymatic analysis revealed an abundance of catalase in the wild-type strain but decreasing catalase activity in heterozygous mutants and no detectable catalase in a homozygous null mutant. In vitro assays showed the mutant strains to be more sensitive to damage by both neutrophils and concentrations of exogenous peroxide that were sublethal for the parental strain. Compared to the parental strain, the homozygous null mutant strain was far less virulent for mice in an intravenous infection model of disseminated candidiasis. Definitive linkage of CAT1 with virulence would require restoration of activity by reintroduction of the gene into mutants. However, initial results in mice, taken together with the enhanced susceptibility of catalase-deficient hyphae to damage by human neutrophils, suggest that catalase may enhance the pathogenicity of C. albicans.

The polymerase chain reaction (PCR) was used to detect the presence of Paracoccidioides brasiliensis in a murine model of disseminated paracoccidioidomycosis. Using a previously identified P. brasiliensis-specific DNA sequence, P. brasiliensis DNA was detected in serum of five experimentally infected mice. The PCR method was able to detect as little as 10 pg of P. brasiliensis DNA in serum, and it was more sensitive than blood culture isolation (five of five were PCR positive versus two of five blood culture positive). There were no amplified fragments in serum from three noninfected control mice. Lung colony counts were similar in all infected mice and reflected a similar degree of P. brasiliensis infection at the time the samples were drawn. The relatively short processing time for the PCR, when compared with culture, its sensitivity, and the possibility of using serum samples for analysis, are important factors favoring this method for the diagnosis of paracoccidioidomycosis. Future studies should include the detection of P. brasiliensis in patients with different clinical forms of paracoccidioidomycosis.

Amphotericin B has been used in combination, simultaneously or sequentially, with fluconazole and itraconazole. However, there are no data from clinical trials to suggest the most appropriate use of these drug combinations. In vitro work has consistently described antagonism of polyenes and azoles, but new work suggests that hydrophilic azoles (e.g. fluconazole) with amphotericin B may not result in antagonistic effects, whereas lipophilic azoles (e.g. ketoconazole, itraconazole) antagonize the antifungal effects of amphotericin B. Experimental studies in animals with invasive candidiasis show that fluconazole and amphotericin B are not antagonistic and may be additive in their effects. In contrast, itraconazole and amphotericin B are antagonistic in this same murine candidiasis model. In animals infected with Aspergillus, itraconazole plus amphotericin B seem to be antagonistic when used simultaneously and possibly when used sequentially. Nevertheless, initial therapy with amphotericin B followed by itraconazole in patients with aspergillosis is a common clinical strategy. Recent data and concepts concerning the combined use of available antifungal drugs are discussed in this paper.

Quinolone antibacterial drugs inhibit DNA gyrase, a type 2 topoisomerase. Since topoisomerases are present in eukaryotic cells, it was of interest to evaluate the antifungal activities of two clinically available quinolones, ciprofloxacin and trovafloxacin, alone and in combination with amphotericin B or fluconazole, in vitro against Candida albicans and in a murine model of invasive candidiasis. The in vitro activity of trovafloxacin was also tested against other yeasts and molds. In vitro, trovafloxacin exhibited no antifungal activity against any of the fungi (MIC, >250 microg/ml). There was also no effect of the quinolone on the in vitro activity of either antifungal drug. Marked antifungal effects were seen, however, in the murine model of candidiasis. In all experiments, control mice infected intravenously with C. albicans were dead by day 24. While either quinolone had minimal effects on survival of mice when used alone in oral doses of up to 40 mg/kg twice daily, the combination of the quinolone with fluconazole (40 or 80 mg/kg given twice daily by oral gavage) was more effective in prolonging survival than was fluconazole alone. Colony counts of kidneys on days 12 and 30 showed similar reductions in C. albicans recovered from mice treated with fluconazole with or without trovafloxacin or amphotericin B with or without trovafloxacin. Survival of mice treated with a suboptimal dose of amphotericin B (0.2 mg/kg/day) was also improved when trovafloxacin (40 mg/kg) given twice daily was included (0 versus 27%, respectively; P < 0.05). While the mechanisms of action of the combination of trovafloxacin and amphotericin B or fluconazole are unclear, further work focused on fungal topoisomerase inhibition and the mechanism of the antifungal effect of quinolone antibacterial drugs is warranted.

The new triazole derivative SCH 56592 has been tested in a National Committee for Clinical Laboratory Standards-adapted in vitro susceptibility test, and its activity against 12 isolates of Blastomyces dermatitidis yeast-like forms has been compared with those of amphotericin B, itraconazole, and fluconazole. SCH 56592 was the most active of the four compounds, with an MIC at which 90% of the isolates are inhibited of 0.06 microgram/ml and a minimal fungicidal concentration at which 90% of the isolates are inhibited of 4 micrograms/ml. The results of the treatment of mice infected with B. dermatitidis with three different doses of SCH 56592 (25, 5, or 1 mg/kg of body weight), amphotericin B (1 mg/kg), or itraconazole (150 mg/kg) confirmed the potent activity of SCH 56592. Survival was prolonged at each dose of SCH 56592, and sterilization of the lungs occurred in the high-dose group but not in the groups treated with itraconazole or fluconazole. SCH 56592 is a promising new azole antifungal drug that should be studied in humans with blastomycosis.

The scarcity of reported cases of paracoccidioidomycosis and AIDS remains unexplained. We review the details of the 27 cases reported in the medical literature. Paracoccidioidomycosis occurs in patients with advanced AIDS who are not receiving prophylaxis for Pneumocystis carinii pneumonia with trimethoprim-sulfamethoxazole, which is also effective against Paracoccidioides brasiliensis. Clinical manifestations include prolonged fever, weight loss, generalized lymphadenopathy, splenomegaly, hepatomegaly, and skin rash. Diagnosis can often be made by direct microscopic examination and culture of the fungus from skin and lymph node specimens and occasionally from sputum, blood, spinal fluid, and bone marrow specimens. Since antibodies to P. brasiliensis are occasionally detected, the diagnosis should not be ruled out for patients whose serology is negative. Despite specific therapy with different regimens, the overall mortality of paracoccidioidomycosis among patients with AIDS is high (30%). The prognosis can be improved by earlier diagnosis and aggressive therapy with amphotericin B, followed by lifelong immunosuppressive therapy with trimethoprim-sulfamethoxazole. Health care providers caring for human immunodeficiency virus-infected patients who live or have resided in areas in which paracoccidioidomycosis is endemic must be aware of the possibility that this systemic mycosis may occur and have potentially severe consequences.

During a comparative trial of amphotericin B vs. fluconazole for treatment of candidemia in nonneutropenic patients, data on the management of intravascular catheters were collected. Complete records were available for 91% of the 206 study patients. For the subset of patients with a catheter in place at the time of their first positive blood culture, removal and replacement of all intravascular catheters without exchange over a guidewire from a preexisting line on or before the first day the study drug was administered were associated with a reduction in the subsequent mean duration (+/- SE) of candidemia, from 5.6 +/ -0.8 days to 2.6 +/- 0.5 days (P < .001).

A case of Rhodotorula minuta central venous catheter infection with fungaemia is described in a patient with advanced acquired immunodeficiency syndrome (AIDS), HIV nephropathy, end-stage renal disease requiring haemodialysis, and a permanent Quinton catheter in place for 6 months. At the time of fungaemia, the patient was taking 100 mg fluconazole per os daily for a previous episode of Candida oesophagitis. R. minuta central venous catheter infection with fungaemia was successfully treated with 455 mg total dose amphotericin B (0.6 mg kg-1 day-1) over 25 days without removal of the catheter. In vitro antifungal susceptibility testing for R. minuta revealed a minimum inhibitory concentration to fluconazole of > 100 micrograms ml-1 and to amphotericin B of 1.2 microgram ml-1. Clinically evident fungaemia, even with an unusual organism such as R. minuta, may occur in patients with intravenous catheters, and while the immunosuppressed patient is receiving azole therapy.

Identification of cryptococcal infection while it is still in its pulmonary phase might improve the prognosis for patients with AIDS who contract cryptococcosis. Since cryptococcal pneumonia is infrequently diagnosed in the AIDS patient, especially compared with the frequency of diagnosis of cryptococcal meningitis, this retrospective study was designed to investigate the frequency of pulmonary complaints in the months before diagnosis of cryptococcal meningitis. The medical records of 18 patients diagnosed with cryptococcal meningitis were analyzed. Of 18 patients, 14 (78%) had respiratory symptoms during the 4-month period before meningitis appeared, as compared with nine of 18 (50%) at the time of diagnosis and four of 16 (25%) in the 4 months following diagnosis. Seven of the 14 cases of pulmonary disease prediagnosis were of unknown etiology; three were eventually diagnosed as cryptococcal infections during evaluation of the meningitis. The remaining eight infections were attributed to bacteria, respiratory viruses, or Pneumocystis carinii, although three of these cultures also contained yeast, presumed to be Candida species, which were not further examined. Our data suggest the importance of singling out AIDS patients who may have pulmonary cryptococcosis. Cryptocococcsis should be included in the differential diagnosis of pulmonary infection in HIV-positive patients with CD4+ lymphocyte counts < 200/mm3, and full identification of yeasts recovered from sputum or bronchoalveolar lavage fluid cultures should be done. A larger study should be undertaken to better define the incidence of clinically recognizable pulmonary cryptococcosis in AIDS patients.

The effects of human bronchoalveolar macrophages (BAMs) on Blastomyces dermatitidis conidia were investigated. Macrophage monolayers were incubated for 5 days with or without interferon (IFN)-gamma or macrophage colony-stimulating factor (M-CSF) before challenge with conidia for 48 h at 37 degrees C. Hyphal growth (germination) was inhibited 12% by resident BAMs (P < .05). In contrast, resident BAMs blocked conidial phase transition by 88% (P < .05). Intermediate forms, aggregates of large cells in clums (not conidia or yeasts by morphologic criteria), appeared after incubation with BAMs and grew into typical yeasts once removed from the BAMs. IFN-gamma and M-CSF inhibited the ability of BAMs to block phase transition but not germination. Human BAMs demonstrated fungicidal and fungistatic activity against B. dermatitidis conidia independent of reactive oxygen intermediates and had greater effects on phase transition than on germination. The phase transition-associated fungicidal and fungistatic activities of BAMs were inhibited by IFN-gamma and M-CSF.

We cloned and sequenced a species-specific 110-bp DNA fragment from Paracoccidioides brasiliensis. The DNA fragment was generated by PCR with primers complementary to the rat beta-actin gene under a low annealing temperature. Comparison of the nucleotide sequence, after excluding the primers, with those in the GenBank database identified approximately 60% homology with an exon of a major surface glycoprotein gene from Pneumocystis carinii and a fragment of unknown function in Saccharomyces cerevisiae chromosome VIII. By Southern hybridization analysis, the 32P-labelled fragment detected 1.0- and 1.9-kb restriction fragments within whole-cell genomic DNA of P. brasiliensis digested with HindIII and PstI, respectively, but failed to hybridize to genomic DNAs from Candida albicans, Blastomyces dermatitidis, Cryptococcus neoformans, Aspergillus fumigatus, Saccharomyces cerevisiae, Pneumocystis carinii, rat tissue, or humans under low-stringency hybridization conditions. Additionally, the specific DNA fragment from three different P. brasiliensis isolates (Pb18, RP18, RP17) was amplified by PCR with primers mostly complementary to nonactin sequences of the 110-bp DNA fragment. In contrast, there were no amplified products from other fungus genomic DNAs previously tested, including Histoplasma capsulatum. To date, this is the first species-specific DNA fragment cloned from P. brasiliensis which might be useful as a diagnostic marker for the identification and classification of different P. brasiliensis isolates.

The in vitro and in vivo activities of a new broad-spectrum triazole derivative, SCH 51048, against Blastomyces dermatitidis were evaluated. As determined by using the new National Committee for Clinical Laboratory Standards proposed standard for susceptibility testing of yeasts, SCH 51048 was the most active of the four agents tested in vitro against 13 strains of B. dermatitidis. In a well-described murine model of acute pulmonary blastomycosis, SCH 51048 was comparable to amphotericin B and at least 30 times more active than itraconazole. On the basis of these experiments, clinical evaluation of SCH 51048 for the use in treatment of human blastomycosis should proceed.

A study was performed to assess the in vivo relevance of the in vitro antagonism between fluconazole and amphotericin B against Candida albicans. Combinations of fluconazole and amphotericin B were explored for their efficacies against acute (100% mortality in 2 to 5 days) or less acute (100% mortality in 30 days) invasive candidiasis infections in mice with healthy immune systems and immunocompromised mice. Treatment efficacy was assessed by protection from mortality and/or a reduction in the fungal burden in tissue. In models of acute infection in mice with healthy immune systems or less acute infection in immunocompromised mice, combinations of fluconazole and amphotericin B were superior to fluconazole alone, and the effects were at least additive. Combination therapy was at least as efficacious as amphotericin B alone. In a different model of less acute infection in mice with healthy immune systems, combinations of fluconazole and amphotericin B showed no interactions and were no better than either drug alone. We conclude that combination therapy with fluconazole and amphotericin B is not antagonistic in vivo, in contrast to published in vitro studies, and, consequently, suggest that combination therapy should be considered in the management of clinical candidiasis.

Three microtiter plate adaptations of the NCCLS proposed standard for antifungal susceptibility testing were evaluated and compared to the NCCLS broth macrodilution method. Thirteen different fungi, including yeasts and moulds were studied. The first microtiter based method was performed exactly as described for the tube dilution assay, with the exception of performance of the assay in 100 microliter in wells of the microtiter plate. The second assay was the same as the first, except for the deletion of phenol red from the RPMI 1640. The third microtiter assay was based on the reduction of the formazan dye, XTT, after only 24 hours of incubation. All three microtiter methods compared favorably with the macrodilution method, when visually read after either 24 or 48 hours of incubation. Minimum inhibitory concentrations obtained by the XTT assay were usually lower than those obtained by the methods requiring a visual end point determination. Results were reproducible and comparable to those obtained with the NCCLS method. We conclude that microtiter plate adaptation of the NCCLS proposed standard is feasible and the presence of phenol red does not alter the results with the drugs tested. A 24 hour assay using XTT may provide a quicker and more quantitative method of susceptibility testing of fungi. Further investigation of this approach is warranted.

Background: Amphotericin B has long been the standard treatment for candidemia, but its use is complicated by its toxicity. More recently, fluconazole, a water-soluble triazole with activity against candida species and little toxicity, has become available. We conducted a multicenter randomized trial that compared amphotericin B with fluconazole as treatment for candidemia., Methods: To be eligible, patients had to have a positive blood culture for candida species, a neutrophil count > or = 500 per cubic millimeter, and no major immunodeficiency. Patients were randomly assigned to receive either amphotericin B (0.5 to 0.6 mg per kilogram of body weight per day) or fluconazole (400 mg per day), each continued for at least 14 days after the last positive blood culture. Outcomes were assessed by a group of investigators blinded to treatment assignment., Results: Of the 237 patients enrolled, 206 met all entry criteria. The most common diagnoses were renal failure, nonhematologic cancer, and gastrointestinal disease. There was no statistically significant difference in outcome: of the 103 patients treated with amphotericin B, 81 (79 percent) were judged to have been treated successfully, as were 72 of the 103 patients treated with fluconazole (70 percent P = 0.22; 95 percent confidence interval for the difference, -5 to 23 percent). The bloodstream infection failed to clear in 12 patients in the amphotericin group and 15 in the fluconazole group; the species most commonly associated with failure was Candida albicans. There were 41 deaths in the amphotericin group and 34 deaths in the fluconazole group (P = 0.20). Intravascular catheters appeared to be the most frequent source of candidemia. There was less toxicity with fluconazole than with amphotericin B., Conclusions: In patients without neutropenia and without major immunodeficiency, fluconazole and amphotericin B are not significantly different in their effectiveness in treating candidemia.

Background: Invasive aspergillosis is the most common invasive mould infection and a major cause of mortality in immunocompromised patients. Response to amphotericin B, the only antifungal agent licensed in the United States for the treatment of aspergillosis, is suboptimal., Methods: A multicenter open study with strict entry criteria for invasive aspergillosis evaluated oral itraconazole (600 mg/d for 4 days followed by 400 mg/d) in patients with various underlying conditions. Response was based on clinical and radiologic criteria plus microbiology, histopathology, and autopsy data. Responses were categorized as complete, partial, or stable. Failure was categorized as an itraconazole failure or overall failure., Results: Our study population consisted of 76 evaluable patients. Therapy duration varied from 0.3 to 97 weeks (median 46). At the end of treatment, 30 (39%) patients had a complete or partial response, and 3 (4%) had a stable response, and in 20 patients (26%), the protocol therapy was discontinued early (at 0.6 to 54.3 weeks) because of a worsening clinical course or death due to aspergillosis (itraconazole failure). Twenty-three (30%) patients withdrew for other reasons including possible toxicity (7%) and death due to another cause but without resolution of aspergillosis (20%). Itraconazole failure rates varied widely according to site of disease and underlying disease group: 14% for pulmonary and tracheobronchial disease, 50% for sinus disease, 63% for central nervous system disease, and 44% for other sites; 7% in solid organ transplant, 29% in allogeneic bone marrow transplant patients, and 14% in those with prolonged granulocytopenia (median 19 days), 44% in AIDS patients, and 32% in other host groups. The relapse rates among those who completed therapy and those who discontinued early for possible toxicity were 12% and 40%, respectively; all were still immunosuppressed., Conclusion: Oral itraconazole is a useful alternative therapy for invasive aspergillosis with response rates apparently comparable to amphotericin B. Relapse in immunocompromised patients may be a problem. Controlled trials are necessary to fully assess the role of itraconazole in the treatment of invasive aspergillosis.

The induction of heat-shock proteins has been postulated to play a role not only in thermo-adaptation, but also in phase transition of the dimorphic fungi. In this study, we used yeast and mycelial forms of the thermally dimorphic fungus Paracoccidioides brasiliensis to evaluate the effect of temperature on the induction of the heat-shock response. We also evaluated protein synthesis by P. brasiliensis caused by exposure to low pH and H2O2. Analysis of protein synthesis by SDS-PAGE disclosed that P. brasiliensis mycelia increased synthesis of all major constitutive proteins when stressed at 37 degrees C and increased synthesis of three non-constitutive proteins of 134, 82 and 28 kDa at 40 degrees C. Yeasts incubated at 40 degrees C showed decreased synthesis of five constitutive proteins (136, 98, 62, 57 and 54 kDa) and the appearance of three new proteins (134, 82 and 28 kDa). There was a decrease in the synthesis of all major constitutive proteins except for three proteins of 141, 136 and 16 kDa when yeast cells were incubated at 25 degrees C. When stressed by low pH and H2O2, P. brasiliensis yeast increased synthesis of one (134 kDa) and five (134, 104, 82, 52 and 40 kDa) non-constitutive proteins, respectively. P. brasiliensis mycelia and yeast forms disclosed the same profile of protein synthesis when stressed at temperatures that trigger phase transition (37 degrees C for mycelia; 25 degrees C for yeast).(ABSTRACT TRUNCATED AT 250 WORDS)

The efficacy of a new triazole antifungal agent, saperconazole, in a murine model of disseminated candidiasis was studied. Mice were intravenously infected with Candida albicans blastoconidia and treated for 14 days with oral saperconazole, intraperitoneal amphotericin B, or a combination of these. Amphotericin B alone was the most efficacious in prolonging survival and in decreasing renal colony counts, usually with complete sterilization of the kidneys by the end of the treatment course. Saperconazole improved survival rates and effected a decrease in renal colony counts, but kidneys were not microbiologically sterilized. Combination therapy with saperconazole and amphotericin B did not result in a decrease in the efficacy of amphotericin B by either end point (survival or renal colony counts). High-pressure liquid chromatographic analysis of saperconazole concentrations in serum indicated low levels of absorption of the drug. We conclude that saperconazole is effective in the treatment of murine invasive candidiasis and that the theoretical concern about adverse interactions between the two drugs does not apply to the dosages studied in these experiments.

Background and Methods: We describe four patients without major risk factors for human immunodeficiency virus (HIV) infection, each of whom presented with severe opportunistic infections and was found to have idiopathic CD4+ T-lymphocytopenia. We performed assays to detect the presence of retroviruses and undertook immunophenotyping of subgroups of peripheral-blood lymphocytes., Results: The opportunistic infections at presentation included Pneumocystis carinii pneumonia, cryptococcal meningitis (two patients, one with concurrent pulmonary tuberculosis), and histoplasma-induced brain abscess. During 10 to 68 months of observation, none of the four patients had evidence of infection with HIV type 1 or 2 or human T-cell lymphotropic virus type I or II on the basis of epidemiologic, serologic, or polymerase-chain-reaction studies or culture, nor was there any detectable reverse transcriptase activity. Although all the patients had severe, persistent CD4+ T-lymphocytopenia (range, 12 to 293 cells per cubic millimeter), the CD4+ cell count progressively declined in only one and was accompanied by multiple opportunistic infections. All four patients had significantly reduced numbers of circulating CD8+ T cells, natural killer cells, or B cells (or all three)., Conclusions: These four patients had idiopathic CD4+ T-lymphocytopenia with opportunistic infections but no evidence of HIV infection. Instead of the progressive, selective depletion of CD4+ T cells characteristic of HIV infection, some patients with idiopathic immunodeficiency have stable CD4+ cell counts accompanied by reductions in the levels of several other lymphocyte subgroups.

The effects of fluconazole on the candidacidal activity of human neutrophils were investigated. Three clinical isolates of Candida albicans were studied in a colony count assay and the presence of fluconazole during incubation of yeasts with neutrophils had no effect on neutrophil candidacidal activity. These results, using a different assay and three additional isolates, confirm previous studies showing that fluconazole does not interfere with the ability of neutrophils to kill C. albicans.

Amphotericin B systemically infused into anesthetized rats at the rate of 0.4 mg/kg body weight over 20 min reproducibly induced renal vasoconstriction and renal cortical hypoxemia. By contrast, when infused with albumin (3 g/dl), amphotericin B did not reduce renal blood flow and did not affect renal cortical oxygenation. In vitro, hemolysis induced by amphotericin was also markedly reduced in the presence of albumin. Albumin did not appear to reduce the antibiotic effect of amphotericin in vitro. It was concluded that amphotericin B toxicity may be considerably reduced if administered in an albumin vehicle.

Background: After primary treatment for cryptococcal meningitis, patients with the acquired immunodeficiency syndrome (AIDS) require some form of continued suppressive therapy to prevent relapse., Methods: We conducted a multicenter, randomized trial that compared fluconazole (200 mg per day given orally) with amphotericin B (1 mg per kilogram of body weight per week given intravenously) in patients with AIDS who had completed primary therapy for cryptococcal meningitis with amphotericin B (greater than or equal to 15 mg per kilogram). To be eligible, patients had to have at least two negative cultures of cerebrospinal fluid immediately before randomization. The primary end point was relapse of cryptococcal disease as confirmed by biopsy or culture., Results: Of 218 patients initially enrolled, 119 were assigned to fluconazole and 99 to amphotericin B. Twenty-three patients were found not to have met the entry criteria; six other patients assigned to amphotericin B did not receive it and were lost to follow-up. Of the remaining 189 patients, after a median follow-up of 286 days 14 of 78 receiving amphotericin B (18 percent) and 2 of 111 assigned to fluconazole (2 percent) had relapses of symptomatic cryptococcal disease (P less than 0.001 by Fisher's exact test). There was a difference of 19 percent in the estimated probability of remaining relapse-free at one year between the fluconazole group (97 percent) and the amphotericin B group (78 percent) (95 percent confidence interval, 7 percent to 31 percent; P less than 0.001). Serious drug-related toxicity was more frequent in the amphotericin B group (P = 0.02), as were bacterial infections (P = 0.004) and bacteremia (P = 0.002)., Conclusions: Fluconazole taken by mouth is superior to weekly intravenous therapy with amphotericin B to prevent relapse in patients with AIDS-associated cryptococcal meningitis after primary treatment with amphotericin B.

Mucormycosis refers to the disease caused by a growing number of members of the Mucorales. Typically an airborne infection, primary disease is initiated in the upper or lower airways and is associated with the clinical development of sinusitis, rhinocerebral mucormycosis, or pulmonary infection. Dissemination of infection to skin, brain, and other sites is less common, but direct extension of the infection to contiguous sites is common if patients do not receive aggressive surgical and medical therapy. Risk factors for the development of mucormycosis include diabetic ketoacidosis; neutropenia; protein-calorie malnutrition; and iron overload, with or without the concomitant use of deferoxamine. This last association has only recently been recognized and has emerged as a major life-threatening complication for patients who are undergoing hemodialysis. Intravenous drug abusers may inject spores of Mucorales with their drugs and may present with space-occupying lesions of the CNS. The underlying immunologic defects that are responsible for predisposing different populations of patients to the development of mucormycosis are not well understood, and there is no unifying theory to explain why most individuals have innate immunity to this group of fungi. Patients with mucormycosis who are managed aggressively (i.e., those who undergo surgical debridement and who receive therapy with iv amphotericin B) may have increased rates of survival. The role of new azole derivatives in the treatment of mucormycosis is unknown.