John R. Perfect

Clinical Practice Guidelines for the Management of Cryptococcal Disease: 2010 Update by the Infectious Diseases Society of America

Cryptococcosis is a global invasive mycosis associated with significant morbidity and mortality. These guidelines for its management have been built on the previous Infectious Diseases Society of America guidelines from 2000 and include new sections. There is a discussion of the management of cryptococcal meningoencephalitis in 3 risk groups: (1) human immunodeficiency virus (HIV)-infected individuals, (2) organ transplant recipients, and (3) non-HIV-infected and nontransplant hosts. There are specific recommendations for other unique risk populations, such as children, pregnant women, persons in resource-limited environments, and those with Cryptococcus gattii infection. Recommendations for management also include other sites of infection, including strategies for pulmonary cryptococcosis. Emphasis has been placed on potential complications in management of cryptococcal infection, including increased intracranial pressure, immune reconstitution inflammatory syndrome (IRIS), drug resistance, and cryptococcomas. Three key management principles have been articulated: (1) induction therapy for meningoencephalitis using fungicidal regimens, such as a polyene and flucytosine, followed by suppressive regimens using fluconazole; (2) importance of early recognition and treatment of increased intracranial pressure and/or IRIS; and (3) the use of lipid formulations of amphotericin B regimens in patients with renal impairment. Cryptococcosis remains a challenging management issue, with little new drug development or recent definitive studies. However, if the diagnosis is made early, if clinicians adhere to the basic principles of these guidelines, and if the underlying disease is controlled, then cryptococcosis can be managed successfully in the vast majority of patients.

Voriconazole Compared with Liposomal Amphotericin B for Empirical Antifungal Therapy in Patients with Neutropenia and Persistent Fever

BACKGROUND Patients with neutropenia and persistent fever are often treated empirically with amphotericin B or liposomal amphotericin B to prevent invasive fungal infections. Antifungal triazoles offer a potentially safer and effective alternative. METHODS In a randomized, international, multicenter trial, we compared voriconazole, a new second-generation triazole, with liposomal amphotericin B for empirical antifungal therapy. RESULTS A total of 837 patients (415 assigned to voriconazole and 422 to liposomal amphotericin B) were evaluated for success of treatment. The overall success rates were 26.0 percent with voriconazole and 30.6 percent with liposomal amphotericin B (95 percent confidence interval for the difference, -10.6 to 1.6 percentage points); these rates were independent of the administration of antifungal prophylaxis or the use of colony-stimulating factors. There were fewer documented breakthrough fungal infections in patients treated with voriconazole than in those treated with liposomal amphotericin B (8 [1.9 percent] vs. 21 [5.0 percent], P=0.02). The voriconazole group had fewer cases of severe infusion-related reactions (P<0.01) and of nephrotoxicity (P<0.001). The incidence of hepatotoxicity was similar in the two groups. Patients receiving voriconazole had more episodes of transient visual changes than those receiving liposomal amphotericin B (22 percent vs. 1 percent, P<0.001) and more hallucinations (4.3 percent vs. 0.5 percent, P<0.001). Parenteral voriconazole was changed to the oral formulation in 22 percent of the voriconazole group, with a reduction in the mean duration of hospitalization by one day in all patients (P=0.17) but by two days in patients at high risk (P=0.03). CONCLUSIONS Voriconazole is a suitable alternative to amphotericin B preparations for empirical antifungal therapy in patients with neutropenia and persistent fever.

Treatment of Invasive Aspergillosis with Posaconazole in Patients Who Are Refractory to or Intolerant of Conventional Therapy: An Externally Controlled Trial

BACKGROUND Invasive aspergillosis is an important cause of morbidity and mortality in immunocompromised patients. Current treatments provide limited benefit. Posaconazole is an extended-spectrum triazole with in vitro and in vivo activity against Aspergillus species. METHODS We investigated the efficacy and safety of posaconazole oral suspension (800 mg/day in divided doses) as monotherapy in an open-label, multicenter study in patients with invasive aspergillosis and other mycoses who were refractory to or intolerant of conventional antifungal therapy. Data from external control cases were collected retrospectively to provide a comparative reference group. RESULTS Cases of aspergillosis deemed evaluable by a blinded data review committee included 107 posaconazole recipients and 86 control subjects (modified intent-to-treat population). The populations were similar and balanced with regard to prespecified demographic and disease variables. The overall success rate (i.e., the data review committee-assessed global response at the end of treatment) was 42% for posaconazole recipients and 26% for control subjects (odds ratio, 4.06; 95% confidence interval, 1.50-11.04; P=.006). The differences in response between the modified intent-to-treat treatment groups were preserved across additional, prespecified subsets, including infection site (pulmonary or disseminated), hematological malignancy, hematopoietic stem cell transplantation, baseline neutropenia, and reason for enrollment (patient was refractory to or intolerant of previous antifungal therapy). An exposure-response relationship was suggested by pharmacokinetic analyses. CONCLUSIONS Although the study predates extensive use of echinocandins and voriconazole, these findings demonstrate that posaconazole is an alternative to salvage therapy for patients with invasive aspergillosis who are refractory to or intolerant of previous antifungal therapy.

Voriconazole treatment for less-common, emerging, or refractory fungal infections

Treatments for invasive fungal infections remain unsatisfactory. We evaluated the efficacy, tolerability, and safety of voriconazole as salvage treatment for 273 patients with refractory and intolerant-to-treatment fungal infections and as primary treatment for 28 patients with infections for which there is no approved therapy. Voriconazole was associated with satisfactory global responses in 50% of the overall cohort; specifically, successful outcomes were observed in 47% of patients whose infections failed to respond to previous antifungal therapy and in 68% of patients whose infections have no approved antifungal therapy. In this population at high risk for treatment failure, the efficacy rates for voriconazole were 43.7% for aspergillosis, 57.5% for candidiasis, 38.9% for cryptococcosis, 45.5% for fusariosis, and 30% for scedosporiosis. Voriconazole was well tolerated, and treatment-related discontinuations of therapy or dose reductions occurred for <10% of patients. Voriconazole is an effective and well-tolerated treatment for refractory or less-common invasive fungal infections.

Amphotericin B Lipid Complex for Invasive Fungal Infections: Analysis of Safety and Efficacy in 556 Cases

The safety and antifungal efficacy of amphotericin B lipid complex (ABLC) were evaluated in 556 cases of invasive fungal infection treated through an open-label, single-patient, emergency-use study of patients who were refractory to or intolerant of conventional antifungal therapy. All 556 treatment episodes were evaluable for safety. During the course of ABLC therapy, serum creatinine levels significantly decreased from baseline (P < .02). Among 162 patients with serum creatinine values > or = 2.5 mg/dL at the start of ABLC therapy (baseline), the mean serum creatinine value decreased significantly from the first week through the sixth week (P < or = .0003). Among the 291 mycologically confirmed cases evaluable for therapeutic response, there was a complete or partial response to ABLC in 167 (57%), including 42% (55) of 130 cases of aspergillosis, 67% (28) of 42 cases of disseminated candidiasis, 71% (17) of 24 cases of zygomycosis, and 82% (9) of 11 cases of fusariosis. Response rates varied according to the pattern of invasive fungal infection, underlying condition, and reason for enrollment (intolerance versus progressive infection). These findings support the use of ABLC in the treatment of invasive fungal infections in patients who are intolerant of or refractory to conventional antifungal therapy.

Human Dectin-1 Deficiency and Mucocutaneous Fungal Infections

Mucocutaneous fungal infections are typically found in patients who have no known immune defects. We describe a family in which four women who were affected by either recurrent vulvovaginal candidiasis or onychomycosis had the early-stop-codon mutation Tyr238X in the beta-glucan receptor dectin-1. The mutated form of dectin-1 was poorly expressed, did not mediate beta-glucan binding, and led to defective production of cytokines (interleukin-17, tumor necrosis factor, and interleukin-6) after stimulation with beta-glucan or Candida albicans. In contrast, fungal phagocytosis and fungal killing were normal in the patients, explaining why dectin-1 deficiency was not associated with invasive fungal infections and highlighting the specific role of dectin-1 in human mucosal antifungal defense.

Same-sex mating and the origin of the Vancouver Island Cryptococcus gattii outbreak.

Genealogy can illuminate the evolutionary path of important human pathogens. In some microbes, strict clonal reproduction predominates, as with the worldwide dissemination of Mycobacterium leprae, the cause of leprosy. In other pathogens, sexual reproduction yields clones with novel attributes, for example, enabling the efficient, oral transmission of the parasite Toxoplasma gondii. However, the roles of clonal or sexual propagation in the origins of many other microbial pathogen outbreaks remain unknown, like the recent fungal meningoencephalitis outbreak on Vancouver Island, Canada, caused by Cryptococcus gattii. Here we show that the C. gattii outbreak isolates comprise two distinct genotypes. The majority of isolates are hypervirulent and have an identical genotype that is unique to the Pacific Northwest. A minority of the isolates are significantly less virulent and share an identical genotype with fertile isolates from an Australian recombining population. Genotypic analysis reveals evidence of sexual reproduction, in which the majority genotype is the predicted offspring. However, instead of the classic a–α sexual cycle, the majority outbreak clone appears to have descended from two α mating-type parents. Analysis of nuclear content revealed a diploid environmental isolate homozygous for the major genotype, an intermediate produced during same-sex mating. These studies demonstrate how cryptic same-sex reproduction can enable expansion of a human pathogen to a new geographical niche and contribute to the ongoing production of infectious spores. This has implications for the emergence of other microbial pathogens and inbreeding in host range expansion in the fungal and other kingdoms.

NIAID mycoses study group multicenter trial of oral itraconazole therapy for invasive aspergillosis

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.

Voriconazole in the treatment of aspergillosis, scedosporiosis and other invasive fungal infections in children

Objective. To describe the safety and efficacy of voriconazole in children treated within the compassionate release program. Methods. Children received voriconazole on a compassionate basis for treatment of an invasive fungal infection if they were refractory to or intolerant of conventional antifungal therapy. Voriconazole was administered as a loading dose of 6 mg/kg every 12 h iv on Day 1 followed by 4 mg/kg every 12 h iv thereafter. When feasible the route of administration of voriconazole was changed from iv to oral (100 or 200 mg twice a day for patients weighing <40 or ≥40 kg, respectively). Outcome was assessed by investigators at the end of therapy or at the last visit as success (complete or partial response), stable infection, or failure, based on protocol-defined criteria. Results. Sixty-nine children (ages 9 months to 15 years; median, 7 years) received voriconazole; 58 had a proven or probable fungal infection. Among these 58 patients 27 had hematologic malignancies and 13 had chronic granulomatous disease as the most frequent underlying conditions. Forty-two patients had aspergillosis, 8 had scedosporiosis, 4 had invasive candidiasis and 4 had other invasive fungal infections. The median duration of voriconazole therapy was 93 days. At the end of therapy 26 patients (45%) had a complete or partial response. Four patients (7%) had a stable response, 25 (43%) failed therapy and 4 (7%) were discontinued from voriconazole because of intolerance. Success rates were highest in patients with chronic granulomatous disease (62%) and lowest in patients with hematologic malignancies (33%). Two patients experienced treatment-related serious adverse events (ulcerated lips with rash, elevated hepatic transaminases or bilirubin). A total of 23 patients had voriconazole-related adverse events, 3 (13%) of which caused discontinuation of voriconazole therapy. The most commonly reported adverse events included elevation in hepatic transaminases or bilirubin (n = 8), skin rash (n = 8), abnormal vision (n = 3) and a photosensitivity reaction (n = 3). Conclusion. These data support the use of voriconazole for treatment of invasive fungal infections in pediatric patients who are intolerant of or refractory to conventional antifungal therapy.

Cryptococcosis in Human Immunodeficiency Virus-Negative Patients in the Era of Effective Azole Therapy

We conducted a case study of human immunodeficiency virus (HIV)-negative patients with cryptococcosis at 15 United States medical centers from 1990 through 1996 to understand the demographics, therapeutic approach, and factors associated with poor prognosis in this population. Of 306 patients with cryptococcosis, there were 109 with pulmonary involvement, 157 with central nervous system (CNS) involvement, and 40 with involvement at other sites. Seventy-nine percent had a significant underlying condition. Patients with pulmonary disease were usually treated initially with fluconazole (63%); patients with CNS disease generally received amphotericin B (92%). Fluconazole was administered to approximately two-thirds of patients with CNS disease for consolidation therapy. Therapy was successful for 74% of patients. Significant predictors of mortality in multivariate analysis included age > or =60 years, hematologic malignancy, and organ failure. Overall mortality was 30%, and mortality attributable to cryptococcosis was 12%. Cryptococcosis continues to be an important infection in HIV-negative patients and is associated with substantial overall and cause-specific mortality.