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Background: Crohn's disease (CD) represents a significant public health challenge. We identified a combination of beneficial probiotic strains (Saccharomyces boulardii, Lactobacillus rhamnosus, Lactobacillus acidophilus, and Bifidobacterium breve) and amylase that may antagonize elevated bacterial pathogens in the inflamed gut. Our aim was to characterize the effect(s) of this novel probiotic supplement in SAMP1/YitFc (SAMP) mice with CD-like ileitis., Methods: Three groups of 7-week-old SAMP mice were used in this study. The first experimental group was administered 1 dose of the probiotic supplement (probiotic strains + amylase) diluted in sterile phosphate-buffered saline (PBS) (0.25 mg in 100 µL of PBS) every day for 56 days through the gavage technique, the second group had a probiotic supplement (probiotic strains without amylase), and the third group was a control group in which animals were administered sterile PBS. At the end of the treatment, mice were sacrificed and ilea were collected for histological scoring of ileitis and NanoString analysis. Stool samples were evaluated by 16S ribosomal RNA and gas chromatography-mass spectrometry analyses., Results: Histology scores showed that mice treated with probiotics + amylase had a significant decrease of ileitis severity compared with the other 2 groups. 16S ribosomal RNA and gas chromatography-mass spectrometry analysis showed that abundance of species belonging to genus Lachnoclostridium and Mucispirillum schaedleri were significantly increased compared with the other 2 groups, and this increase was associated with augmented production of short-chain fatty acids. NanoString data showed that 21 genes involved in B memory cell development and T cell infiltration were significantly upregulated in probiotic-treated mice and that 3 genes were significantly downregulated., Conclusions: Our data provide experimental proof for a beneficial effect of the designed probiotic formulation on the severity of CD-like ileitis in the SAMP mouse model, involving both alteration of intestinal genetic pathways and microbial rearrangements. Thus, we propose that this novel probiotic mixture should be further tested as an adjuvant therapy in the treatment of biofilm-associated disorders such as CD, in which it has been proven that polymicrobial imbalance plays a critical role in dysbiosis and gut inflammation., (© The Author(s) 2023. Published by Oxford University Press on behalf of Crohn’s & Colitis Foundation. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Inflammatory bowel disease (IBD), a disorder characterized by chronic inflammation of the gastrointestinal (GI) tract and a range of adverse health effects including diarrhea, abdominal pain, vomiting, and bloody stools, affects nearly 3.1 million genetically susceptible adults in the United States today. Although the etiology of IBD remains unclear, genetics, stress, diet, and gut microbiota dysbiosis- especially in immunocompromised individuals- have been identified as possible causes of disease. Although previous research has largely focused on the role of bacteria in IBD pathogenesis, recently observed alterations of fungal load and biodiversity in the GI tract of afflicted individuals suggest interkingdom interactions amongst different gut microbial communities, particularly between bacteria and fungi. These discoveries point to the potential utilization of treatment approaches such as antibiotics, antifungals, probiotics, and postbiotics that target both bacteria and fungi in managing IBD. In this review, we discuss the impact of specific fungi on disease pathogenesis, with a focus on the highly virulent genus Candida and how the presence of certain co-enzymes impacts its virulence. In addition, we evaluate current gut microbiome-based therapeutic approaches with the intention of better understanding the mechanisms behind novel therapies., (© The Author(s) 2022. Published by Oxford University Press on behalf of Crohn’s & Colitis Foundation. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: The rates of infection after inflatable penile prosthesis (IPP) range from 1% to 3%; however, with changes in antibiotic practice intraoperatively and the incorporation of local anesthetic dips, it is unclear whether this incidence of infection is affected., Aim: To evaluate whether the utilization of local anesthetic dips and antifungal solutions affect the efficacy of previously established dips across multiple species and strains., Methods: Strains of four different species of bacteria and one fungus were prepared in a standardized confluency. A standardized, and sterile protocol was used to punch out 6mm circular discs from the reservoir of a Coloplast Titan device. The discs were submerged in a standardized concentration of antimicrobials (combinations of Bactrim, Rifampin + Gentamicin, Vancomycin, Zosyn, and Amphotericin B) and plated. The zone of inhibition (ZOI) was measured at 24, 48, and 72 hours. Five repetitions of each organism was performed (>1700 discs), and the mean ZOI was calculated. Saline and DMSO were used as control on each plate., Outcomes: Main outcome was the ZOI identified with each antibiotic solution, and the secondary outcome was the efficacy of the antibiotic over the course of 72 hours., Results: Difference in antibiotic efficacy was seen when each bacterial species was evaluated separately, with rifampin and gentamicin having less efficacy towards all organisms other than S. epidermidis. When looking specifically at the Candida species, amphotericin B was significantly better than other antibiotic solutions. In regards to efficacy of antibiotics over 72 hours, all treatment groups showed a decrease in ZOI over time. However, treatment groups that included rifampin demonstrated the ability to inhibit S. aureus and S. epidermidis over the 72-hour period., Clinical Implications: To improve clinical practice and alleviate concerns that incorporation of local anesthetic and antifungals may decrease the efficacy of antibiotic solutions., Strengths and Limitations: A major strength of the study is that it is the most robust and scientifically sound study performed on this topic with approximately 1700 repetitions. It is also the first study of its kind to include a wide spectrum of bacterial and fungal strains and antibiotic solutions along with temporal data on drug elution over a 72-hour period. A limitation of the study is the in vitro model, and this needs to be validated in a clinical setting., Conclusions: Dipping prosthetics in antifungal and local anesthetic does not decrease the efficacy of the antimicrobials. The drug elution capabilities of the hydrophilic coating lasts primarily for 24-48hours. Mishra K, Bukavina L, Long L, et al. Do Antifungals and Local Anesthetic Affect the Efficacy of Antibiotic Dipping Solution?. J Sex Med 2021;18:966-973., (Copyright © 2021 International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.)

Background: Extracorporeal treatments (ECTRs) are used for different conditions, including replacement of organ function and poisoning. Current recommendations for ECTRs in various poisonings suggest that intermittent haemodialysis (IHD) is the most efficient technique. However, the practicality of these recommendations is poorly defined in view of limited information on availability and cost worldwide., Methods: A survey invitation to an Internet-based questionnaire was emailed between January 2014 and March 2015 to members of international societies to determine the availability, time to initiation and cost of ECTRs (including filters, dialysate, catheter, anticoagulant and nursing/physician salary). The median cost ratio of every ECTR compared with IHD performed in the same institution were presented., Results: The view rate was estimated at 28.1% (2532/9000), the participation rate was 40.1% (1015/2532) and the completion rate was 16.0% (162/1015). Respondents originated from 89 countries, and nearly three-fourths practiced in a tertiary care centre. A total of 162 respondents provided sufficient data for in-depth analysis. IHD was the most available acute ECTR (96.9%), followed by therapeutic plasma exchange (TPE; 68.3%), continuous renal replacement therapy (CRRT; 62.9%), peritoneal dialysis (PD; 44.8%), haemoperfusion (HP; 30.9%) and liver support devices (LSDs; 14.7%). IHD, CRRT and HP were the shortest to initiate (median = 60 min). The median cost ratios of each ECTR compared with IHD were 1.7 for CRRT and HP, 2.8 for TPE, 6.5 for LSDs and 1.4 for PD (P < 0.001 for all). The median cost ratio of a 4-h IHD treatment compared with 1 day in the intensive care unit was 0.6 (P =  0.2)., Conclusions: IHD appears to be the most widely available ECTR worldwide and is at least 30% less expensive than other ECTRs. The superior efficacy of IHD for enhanced elimination, added to its lower cost and wider availability, strengthens its preference as the ECTR of choice in most cases of acute poisoning., Keywords: costing, CRRT, EXTRIP, hemodialysis, hemoperfusion., (© The Author 2017. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.)

Candida biofilm-associated infections of central venous catheters are a challenging therapeutic problem. Recent in vitro and in vivo studies of the structure, formation, pathogenesis, and treatment establish a rationale for new approaches to management of these tenacious infections., (© The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)

Background: Approval of topical onychomycosis drugs by regulatory agencies may be negatively impacted by an overly stringent definition of complete cure, which includes nail clearing plus mycological cure., Objectives: In this position paper, we discuss interpretation of mycological outcome and clinical trial length., Methods: We reviewed data from seven international onychomycosis trials that enrolled subjects with positive KOH and dermatophyte-positive culture at screening followed by 48 weeks of treatment. Further, we examined 94 KOH-positive/culture-negative week 52 follow-up samples for morphological hyphal damage., Results: From 3054 samples collected at week 52 follow-up visits, 2360 were culture-negative. However, a significant percentage (78.7%) of these subungual samples (n = 1857) remained KOH-positive. From the subset of follow-up samples examined for morphological changes, we identified hyphal breakage or distortion in 56 direct smears (60%), which may indicate nonviability., Conclusions: Reassessment of the definition of onychomycosis cure is critical. For clinical trials of topical agents, length of treatment should be re-examined. Further, in our experience, a high rate of subungual debris samples remained direct smear-positive while converting to negative culture. Evidence of morphological hyphal damage suggests that late-visit microscopic results may be false-positives. Therefore, the absence of clinical signs following an adequate washout period, coupled with a negative culture, with or without negative microscopy, should be considered the definition of onychomycosis cure., (© 2013 British Association of Dermatologists.)

The in vivo efficacy of terbinafine was compared to lanoconazole and luliconazole in the topical treatment of dermatophytosis caused by Trichophyton mentagrophytes using a guinea pig model. Topical antifungal treatment commenced three days post-infection, and each agent was applied once daily for seven consecutive days. Upon completion of the treatment period, evaluations of clinical and mycological efficacies were performed, as was scanning electron microscopy (SEM) analyses. Data showed that while all tested antifungals demonstrated significant mycological efficacy in terms of eradicating the fungi over untreated control, terbinafine and luliconazole showed superior clinical efficacy compared to lanoconazole (P-values < 0.001 & 0.003, respectively). Terbinafine demonstrated the highest clinical percent efficacy. SEM analysis revealed hairs from terbinafine and lanoconazole-treated animals had near complete clearance of fungi, while samples from luliconazole-treated animals were covered with debris and few conidia. This study demonstrates that, in general, terbinafine possessed similar efficacy to lanoconazole and luliconazole in the treatment of dermatophytosis. Terbinafine tended to have superior clinical efficacy compared to the azoles tested, although this difference was not statistically significant against luliconazole. This apparent superiority may be due to the fungicidal activity of terbinafine compared to the fungistatic effect of the other two drugs.

Dermatomycoses are among the world's most common diseases and their incidence has increased over recent years, particularly in immunosuppressed patients. In previous studies, the saponin CAY-1 from cayenne pepper (Capsicum frutescens), has shown antifungal activities against Candida albicans and Aspergillus spp. We therefore studied the in vitro antifungal activity of CAY-1 against non-germinating conidia and hyphae of clinical isolates of the dermatophytes Trichophyton mentagrophytes, T. rubrum, T. tonsurans and Microsporum canis. We used a microdilution method to assess the growth inhibitory activities of CAY-1 against conidia (CLSI document M38-A) and a colorimetric procedure (XTT method) to investigate the metabolic inhibitory activity of CAY-1 against hyphae. The minimal inhibitory concentrations (complete visual growth inhibition) of CAY-1 against non-germinating conidia ranged from 10-20 microg/ml for all dermatophyte isolates included in this investigation. In addition, we found >90% inhibition of hyphal metabolic activity of these same isolates with 10-20 microg/ml of CAY-1. Results indicate that CAY-1 merits further investigation as a potential agent for the treatment of dermatomycoses.

Background. Controversy exists with volume resuscitation using crystalloids or colloids. Renal dysfunction has been reported with some colloids and osmotic agents, but remains poorly defined. Patient. We report the case of a 67-year-old male who had normal kidney function at baseline and who developed anuric ARF in relation to the administration of >10 litres of 10% pentastarch. A renal biopsy confirmed hydropic changes in tubular cells compatible with colloid-induced damage. Conclusion. This case demonstrates that hydroxyethyl starch preparations may be associated with acute kidney injury, and one should carefully consider their use, especially in patients with pre-existing renal dysfunction. Osmotic tubular cell lesions may be long lasting and irreversible.

Background: Our group, in collaboration with seven other laboratories, has recently developed a method to determine the susceptibility of dermatophytes., Objectives: The objective of this study was to determine the terbinafine susceptibility profile of dermatophyte isolates obtained from patients with tinea capitis enrolled in two large worldwide clinical trials and to investigate whether these susceptibilities differ by geographical location. Methods Susceptibilities were determined according to the Clinical and Laboratory Standards Institute M38-A2 standard., Results: From a total of 978 baseline dermatophyte isolates, we selected 301 isolates at random. These included: Trichophyton tonsurans (n = 125), Microsporum canis (n = 94), T. violaceum (n = 63) and M. audouinii (n = 19). The terbinafine minimum inhibitory concentration (MIC) range was 0.001-0.25 microg mL(-1), while MIC(50) and MIC(90) ranged between 0.002 and 0.125 microg mL(-1) and 0.03 and 0.25 microg mL(-1), respectively, for all species tested. MIC(50) and MIC(90) varied by individual species; however, there was no difference in terbinafine MIC among the different species isolated from U.S. and non-U.S. sites., Conclusion: Terbinafine demonstrates potent antifungal activity against dermatophyte isolates obtained from patients with tinea capitis worldwide.

Objectives: The objective of this study was to compare the activity of aminocandin, a new echinocandin with broad-spectrum activity against Candida spp., with that of amphotericin B, caspofungin and fluconazole, in an immunocompetent murine model of haematogenously disseminated candidiasis caused by a fluconazole-resistant Candida albicans., Methods: Mice were infected with a fluconazole-resistant strain of C. albicans and treated with aminocandin 5 and 10 mg/kg intravenously (iv) once and twice weekly, amphotericin B 0.5 mg/kg iv every other day for 5 days, fluconazole 20 mg/kg orally (po) once a day for 5 days and caspofungin 0.5 mg/kg intraperitoneally (ip) once daily for 5 days., Results: Treatment with aminocandin, given iv twice a week, resulted in 100% survival. Further, the tissue fungal burden of the aminocandin group was equivalent to that of amphotericin B (administered every other day) and caspofungin (administered daily)., Conclusions: Aminocandin may be an effective addition to the arsenal of antifungal compounds for the treatment of candidiasis caused by fluconazole-resistant C. albicans.

Aspergillus terreus is an uncommon but emerging fungal pathogen, which causes lethal infections that are often refractory to amphotericin B (AmB). In comparison to Aspergillus fumigatus, A. terreus was resistant to the in vitro fungicidal effects of safely achievable concentrations of AmB. These in vitro findings correlated directly with resistance of A. terreus to AmB in experimental invasive pulmonary aspergillosis. Residual fungal pulmonary burden and galactomannan antigenemia demonstrated persistent infection, despite therapy with deoxycholate AmB or liposomal AmB. By comparison, posaconazole and itraconazole resolved GM antigenemia, reduced residual fungal burden, and improved survival. There were no differences in phagocytic host response to A. terreus versus A. fumigatus; however, the rate of conidial germination of A. terreus was slower. The strain of A. terreus with the highest minimum inhibitory and minimum lethal concentration of AmB also had the lowest membrane ergosterol content. The hyphae of A. terreus in vivo displayed distinctive aleurioconidia, which may be a practical microscopic feature for rapid preliminary diagnosis.

Non-Hodgkin's lymphoma (NHL) remains the second most common malignant complication in patients with human immunodeficiency virus (HIV) infection. As we enter the third decade of the acquired immunodeficiency syndrome (AIDS) epidemic, it is apparent that the evolution of antiretroviral therapy and the emergence of combination antiviral strategies have greatly affected the natural history of HIV infection and its neoplastic complications. For example, there may be a trend for declining incidence of AIDS-related lymphoma in the United States for the first time. However, in regions of the world where the burden of HIV infection is greatest, such as in East Africa, AIDS-related lymphoma is an increasing cause of morbidity and mortality. Treatment of lymphoma has evolved coincident with improvements in antiretroviral therapy. Infusional chemotherapy regimens may offer advantages over other regimens and schedules, but comparative trials have not been done. Clinical trial data are available on which to develop therapeutic strategies to treat this disease in East Africa where pragmatic approaches are needed. Both the differences in manifestations of HIV infection and the inherent difficulties in administering cytotoxic chemotherapy in this part of the world must be taken into consideration in planning therapeutic strategies. Improved understanding of the pathogenesis of HIV infection and lymphoma will likely yield improved therapeutic interventions as well.

Terbinafine has previously been shown to be highly active against dermatophytes and many other filamentous fungi. However, its activity against yeasts is controversial, with earlier reports suggesting that it has low activity, while more recent studies demonstrated that terbinafine is effective against yeasts. In this study, the in vitro activity of terbinafine was evaluated against a broad range of fungal isolates. We examined the susceptibility of 100 yeast strains (10 species including Candida albicans, non-C. albicans, fluconazole-susceptible and -resistant candidal strains), and 184 strains of filamentous fungi and dermatophytes (29 species including Aspergillus, Fusarium, Sporothrix, Trichophyton rubrum, T. mentagrophytes, T. tonsurans, Microsporum canis and Epidermophyton floccosum), using the NCCLS M27-A microdilution methodology for yeasts and a modified M38-P methodology for moulds. The endpoint for terbinafine was defined as 80% inhibition compared with the growth control well. The mean yeast and filamentous fungi minimum inhibitory concentration values +/- SEM (in microg ml(-1)) for terbinafine were: 6.60 +/- 0.73 and 1.04 +/- 0.28, respectively. In conclusion, our data suggest that terbinafine, in addition to its potent activity against dermatophytes, is considerably effective against a broad range of yeasts and filamentous fungi in vitro. Therefore, investigations concerning its antifungal activity in vivo against such organisms should be pursued.

Development of new approaches for treatment of invasive fungal infections encompasses new delivery systems for approved and investigational compounds, as well as exploiting the cell membrane, cell wall and virulence factors as putative antifungal targets. Novel delivery systems consisting of cyclodextrins, cochleates, nanoparticles/nanospheres and long circulating ('stealth') liposomes, substantially modulate the pharmacokinetics of existing compounds, and may also be useful to enhance the delivery of antifungal agents to sites of infection. Further insights into the structure-activity relationship of the antifungal triazoles that target the biosynthesis of ergosterol in the fungal cell membrane have led to the development of highly potent broad spectrum agents, including posaconazole, ravuconazole and voriconazole. Similarly, a novel generation of cell-wall active semisynthetic echinocandin 1,3 beta-glucan inhibitors (caspofungin, FK463, and VER-002) has entered clinical development. These agents have potent and broad-spectrum activity against Candida spp, and potentially useful activity against Aspergillus spp. and Pneumocystis carinii. The ongoing convergence of the fields of molecular pathogenesis, antifungal pharmacology and vaccine development will afford the opportunity to develop novel targets to complement the existing antifungal armamentarium.

The effects of voriconazole on the growth, morphology and lipids of Candida glabrata were studied. MIC data showed that voriconazole was up to 32- to 64-fold more active than fluconazole in its ability to inhibit various C. glabrata strains. Voriconazole inhibited the growth of C. glabrata in a dose-dependent fashion. Electron microscope examination showed that voriconazole treatment affected the external and internal morphology of C. glabrata. Treatment of C. glabrata with voriconazole inhibited ergosterol synthesis and led to accumulation of methylated sterols. In contrast, no significant difference in phospholipid composition was observed between treated and untreated cells.

Accumulating evidence suggests that phospholipase B, secreted by pathogenic fungi such as Candida albicans, Cryptococcus neoformans and Aspergillus fumigatus, functions as one of the virulence factors. In the present study, we have attempted to clone phospholipase B gene from C. albicans. By RT-PCR analysis with degenerate primers based on conserved regions of phospholipase B from Saccharomyces cerevisiae, Penicillium notatum and Torulaspora delbrueckii two similar but different cDNA fragments were obtained. One corresponded to the partial sequence of caPLB1, recently cloned phospholipase B gene from C. albicans by a different approach (Leidich et al.: J Biol Chem 1998; 273: 26078-86). The other fragments contained sequences similar to the corresponding sequences of phospholipase B from other fungi. The presence of two related genes was confirmed by Southern and Northern blot analyses. The full length of the second C. albicans phospholipase B gene (caPLB2) encoded a putative protein with 608 amino acids and contained a potential signal peptide sequence and a putative catalytic region, which are found in phospholipase B from other fungi. Consistent with the findings of caPLB1, caPLB2 also lacks a cluster of hydrophobic amino acids at the COOH-terminal, which may function as a signal of glycosylphosphatidylinositol anchor.

Research on fungi that cause opportunistic infections has increased dramatically during the past few years, largely because these organisms cause significant morbidity and mortality. Most of this research has focused on defining the virulence factors produced by these pathogens, as well as developing methods for the diagnosis of fungal diseases. With regard to studies on the biology of Candida albicans, it is now possible to isolate genes, disrupt their expression, and observe the specific effects of gene disruption on virulence and growth of the organism. Moreover, growth and virulence of this pathogen is also being studied and the effect of environmental factors on gene expression investigated. This subject is especially important in view of the fact that C. albicans can colonize and invade a number of sites in the human body. Thus, its ability to grown in the oral and vaginal tracts, as well as in blood, requires the organism to adapt to a variety of environmental stresses. Here we present observations on the growth, morphogenesis and virulence of the opportunistic fungi C. albicans and Aspergillus fumigatus.

Because of the rapidly increasing incidence of serious candidal infections, a consensus conference of 22 investigators from the United States, Europe, and Japan was held to discuss strategies for the prevention and treatment of deep-organ infections caused by Candida species. Commonly asked questions concerning the management of candidal infections were selected for discussion by the participating investigators. Possible answers to the questions were developed by the investigators, who then voted anonymously for their preferences. In certain instances, unanimity or a strong consensus was the result. In all cases, the full spectrum of responses was recorded and is presented in this report. The forms of candidal infection addressed included candidemia, candiduria, hepatosplenic candidiasis (chronic systemic candidiasis), candidal endophthalmitis, and candidal peritonitis. Prevention and treatment strategies were considered for patients who have undergone surgery, for neutropenic and nonneutropenic patients, and for patients who have undergone bone marrow and solid organ transplantation. The therapeutic roles of amphotericin B (standard and lipid formulations) and the azoles were considered.

The availability of reproducible antifungal susceptibility testing methods now permits analysis of data correlating susceptibility in vitro with outcome in vivo in order to define interpretive breakpoints. In this paper, we have examined the conceptual framework underlying interpretation of antimicrobial susceptibility testing results and then used these ideas to drive analysis of data packages developed by the respective manufacturers that correlate fluconazole and itraconazole MICs with outcome of candidal infections. Tentative fluconazole interpretive breakpoints for MICs determined by the National Committee for Clinical Laboratory Standards' M27-T broth macrodilution methodology are proposed: isolates for which MICs are < or = 8 microg/mL are susceptible to fluconazole, whereas those for which MICs are > or = 64 microg/mL appear resistant. Isolates for which the MIC of fluconazole is 16-32 microg/mL are considered susceptible dependent upon dose (S-DD), on the basis of data indicating clinical response when > 100 mg of fluconazole per day is given. These breakpoints do not, however, apply to Candida krusei, as it is considered inherently resistant to fluconazole. Tentative interpretive MIC breakpoints for itraconazole apply only to mucosal candidal infections and are as follows: susceptible, < or = 0.125 microg/mL; S-DD, 0.25-0.5 microg/mL; and resistant, > or = 1.0 microg/mL. These tentative breakpoints are now open for public commentary.

Recently, the National Committee for Clinical Laboratory Standards (NCCLS) subcommittee on antifungal susceptibility testing published a proposed standard for a broth macrodilution method for in vitro susceptibility testing of yeasts. The major reason for developing such a method is to predict the likely clinical and microbiological outcome of treatment. A number of studies of fluconazole have attempted to correlate in vitro minimum inhibitory concentrations (MICs) with in vivo efficacy in humans by means of a variety of methods, including the NCCLS proposed standard. These studies have clearly demonstrated that the ability to predict clinical outcome with MICs is dependent on the patient population studies. Thus, fluconazole MICs were correlated with clinical outcomes for patients with AIDS-associated oropharyngeal candidiasis. In contrast, fluconazole MICs did not correlate with clinical outcomes for patients with candidemia who did not have AIDS; these patients have numerous factors that can independently influence the response to antifungal therapy aside from the MIC. Data on patients with AIDS-associated cryptococcal meningitis from my laboratory demonstrated that the use of fluconazole MICs in conjunction with clinical variables, such as blood culture results, enhances the ability to predict treatment outcome. More investigations addressing the role of host factors in the vitro-in vivo correlation are necessary before antifungal testing can be useful in guiding therapy.

No method currently exists to predict which patients with acute AIDS-associated cryptococcal meningitis can be effectively treated with fluconazole. The objective of this study was to determine the relationship of cryptococcal susceptibility to fluconazole, along with clinical variables, to the risk of treatment failure for patients with acute AIDS-associated cryptococcal meningitis. Results of in vitro fluconazole susceptibility testing of cryptococcal isolates and data from two clinical trials were analyzed. Susceptibility to fluconazole was determined by means of both microtiter and macrobroth (M27-P) dilution methods. Treatment was defined as successful if the patient was alive at 10 weeks and if a cerebrospinal fluid culture was sterile at that time. Seventy-six patients receiving fluconazole +/- flucytosine were included; therapy failed for 19. Patients whose therapy failed were more likely to have a positive blood and urine culture and a higher titer in serum and cerebrospinal fluid of cryptococcal antigen, and the MIC of fluconazole against their isolates (as determined by the microtiter method) was more likely to be higher; they were less likely to have received flucytosine. Logistic regression modeling revealed that a negative blood culture, a low MIC of fluconazole (per the microtiter method), and treatment with flucytosine were factors independently associated with successful treatment.

Endothelial cells activated with interferon-gamma (IFN-gamma) have been shown to inhibit the replication of Toxoplasma gondii. To determine if this cytokine protects endothelial cells from damage by Candida albicans, human umbilical vein endothelial cells were pretreated with IFN-gamma and infected with C. albicans; endothelial cell damage was measured by the release of 51Cr. Pretreatment with IFN-gamma decreased the extent of endothelial cell injury caused by C. albicans by up to 100% +/- 8.2%. This diminution of endothelial cell damage was confirmed by scanning electron microscopy. The degree of protection was dependent on the concentration of IFN-gamma, with maximum protection occurring at 13 units/mL. Higher concentrations of IFN-gamma were toxic to the endothelial cells. Pretreating the endothelial cells with this cytokine had no effect on candidal germination and growth, suggesting that IFN-gamma stimulates endothelial cells to become resistant to or inhibit the action of candidal virulence factors.

The effects of octenidine and pirtenidine on yeasts (in particular Candida albicans) have been studied. MIC and MCC values have been established as well as the inhibitory effects on growth, budding and germ tube formation. The drugs were shown to cause extensive leakage of cytoplasmic contents from the cells which was correlated with morphological and ultrastructural changes in the yeast.