Françoise Dromer

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.

Incidence and risk factors of immune reconstitution inflammatory syndrome complicating HIV-associated cryptococcosis in France.

Background:Immune reconstitution inflammatory syndrome (IRIS) in association with cryptococcosis has been anecdotically reported following administration of highly active antiretroviral therapy (HAART). Objective:To analyse the incidence and risk factors for IRIS-associated cryptococcosis among HIV-infected patients. Design:Retrospective multicentre study between 1996 and 2000 through the French Cryptococcosis Database. Methods:Subsequent occurrence of IRIS examined in 120 HIV-infected adult patients treated with HAART and experiencing a first episode of culture-confirmed cryptococcosis. Results:Ten patients developed IRIS during the study period, giving an incidence of 10/239, or 4.2/100 person-years [95% confidence interval (CI), 2.2–7.8]. IRIS consisted of acute symptoms consistent with inflammation occurring within a median of 8 months (range, 2–37) after the diagnosis of cryptococcosis in the context of negative cultures and immunological and/or virological response to HAART. Radiology and histopathology detected features compatible with inflammation. Symptom severity required transfer into intensive care units for three patients and use of anti-inflammatory drugs for four. Three patients with evolutive IRIS died. Compared with patients without IRIS for whom complete clinical and microbiological information were available at baseline, previously unknown HIV infection [odds ratio (OR), 4.8; 95% CI, 1.0–21.7], CD4 cell count < 7 × 106 cells/l (OR, 4.0; 95% CI, 0.9–17.2), fungaemia (OR, 6.1; 95% CI, 1.1–35.2) and HAART initiation within 2 months of cryptococcosis diagnosis (OR, 5.50; 95% CI, 1.0–29.6) were independently associated with the risk of subsequent IRIS. Conclusions:IRIS-related cryptococcosis was observed more frequently in severely immunocompromised patients with disseminated infection and HAART initiation soon after the diagnosis.

Recent Exposure to Caspofungin or Fluconazole Influences the Epidemiology of Candidemia: a Prospective Multicenter Study Involving 2,441 Patients

ABSTRACT A prospective multicenter surveillance program on yeast bloodstream infections was implemented in the Paris, France, area without restrictions on ward of hospitalization (intensive care unit, hematology, and surgery) or age (adults and children). The present analysis concerns 2,618 isolates collected over 7 years from 2,441 patients. Centralized species identification and antifungal susceptibility testing using the EUCAST methodology were performed. Almost 10% (232/2,441) of the patients had recently (≤30 days) been treated with antifungal drugs. We analyzed the effect of recent exposure to fluconazole (n = 159) or caspofungin (n = 61) on the proportions of the five major Candida species. For both drugs, preexposure was associated with a decreased prevalence of Candida albicans in favor of less drug-susceptible species (C. glabrata and C. krusei for the former and C. parapsilosis and, to a lesser extent, C. glabrata and C. krusei for the latter; P = 0.001). In the multivariate analysis, the risk of being infected with an isolate with decreased susceptibility to fluconazole was independently associated with an age of ≥15 years (odds ratio [OR] = 2.45; 95% confidence interval [CI] = 1.39 to 4.31; P = 0.002) and with recent exposure to fluconazole (OR = 2.17; 95% CI = 1.51 to 3.13; P < 0.001), while the risk of being infected with an isolate with decreased susceptibility to caspofungin was independently associated with an age <15 years (OR = 2.53; 95% CI = 1.43 to 4.48; P = 0.001) and with recent exposure to caspofungin (OR = 4.79; 95% CI = 2.47 to 9.28; P < 0.001). These findings could influence future recommendations for the management of candidemia.

EUCAST Definitive Document EDef 7.1: method for the determination of broth dilution MICs of antifungal agents for fermentative yeasts: Subcommittee on Antifungal Susceptibility Testing (AFST) of the ESCMID European Committee for Antimicrobial Susceptibility Testing (EUCAST)∗

Antifungal susceptibility tests are performed on fungi that cause disease, especially if they belong to a species exhibiting resistance to commonly used antifungal agents. Antifungal susceptibility testing is also important for resistance surveillance, for epidemiological studies and for comparing the in-vitro activity of new and existing agents. Dilution methods are used to establish the MICs of antimicrobial agents. These are the reference methods for antimicrobial susceptibility testing, and are used mainly to establish the activity of a new antifungal agent, to confirm the susceptibility of organisms that give equivocal results in routine tests, and to determine the susceptibility of fungi where routine dilution tests may be unreliable. Fungi are tested for their ability to produce visible growth in microdilution plate wells containing broth culture media and serial dilutions of the antifungal agents (broth microdilution). The MIC is defined as the lowest concentration (in mg ⁄ L) of an antifungal agent that inhibits the growth of a fungus. The MIC provides information concerning the susceptibility or resistance of an organism to the antifungal agent and can help in making correct treatment decisions. The method described in this document is intended for testing the susceptibility of yeasts that cause clinically significant infections (primarily Candida spp.). The method encompasses only those yeasts that are able to ferment glucose. Thus, the susceptibility of non-fermentative yeasts, e.g., Cryptococcus neoformans, cannot be determined by the current procedure, and the method is not suitable for testing the yeast forms of dimorphic fungi.

Evidence of a Role for Monocytes in Dissemination and Brain Invasion by Cryptococcus neoformans

ABSTRACT The pathogenesis of cryptococcosis, including the events leading to the production of meningoencephalitis, is still largely unknown. Evidence of a transcellular passage of Cryptococcus neoformans across the blood-brain barrier (BBB) and subsequent BBB disruption exists, but the paracellular passage of free yeasts and the role of monocytes in yeast dissemination and brain invasion (Trojan horse method) remain uncertain. We used our model of disseminated cryptococcosis, in which crossing of the BBB starts 6 h after intravenous inoculation, to study paracellular passage of the BBB. We prepared bone marrow-derived monocytes (BMDM) infected in vitro with C. neoformans (BMDM yeasts) and free yeasts and measured fungal loads in tissues. (i) Spleen and lung CFU were >2-fold higher in mice treated with BMDM yeasts than in those treated with free yeasts for 1 and 24 h (P < 0.05), while brain CFU were increased (3.9 times) only at 24 h (P < 0.05). (ii) By comparing the kinetics of brain invasion in naïve mice and in mice with preestablished cryptococcosis, we found that CFU were lower in the latter case, except at 6 h, when CFU from mice inoculated with BMDM yeasts were comparable to those measured in naïve mice and 2.5-fold higher than those in mice with preestablished cryptococcosis who were inoculated with free yeasts. (iii) Late phagocyte depletion obtained by clodronate injection reduced disease severity and lowered the fungal burden by 40% in all organs studied. These results provide evidence for Trojan horse crossing of the BBB by C. neoformans, together with mechanisms involving free yeasts, and overall for a role of phagocytes in fungal dissemination.

Increasing Incidence of Zygomycosis (Mucormycosis), France, 1997–2006

Results were derived from a population-based study using hospital discharge data.

A Global Analysis of Mucormycosis in France: The RetroZygo Study (2005–2007)

BACKGROUND Mucormycosis is a deadly invasive fungal infection whose characteristics are only partially understood. METHODS Data on mucormycosis obtained in France between 2005 and 2007 from 2 notification systems were merged. The 2008 European Organisation for Research and Treatment of Cancer/Mycoses Study Group definition criteria were applied and risk factors for death were analyzed by hazard ratios (HRs) calculated from the Cox proportional hazards regression model. RESULTS A total of 101 cases (60 proven, 41 probable), mostly in men (58%) >50 years (mean age, 50.7 ± 19.9) were recorded. Hematological malignancies represented 50% (median time for occurrence, 8.8 months after disease onset), diabetes 23%, and trauma 18% of cases. Sites of infection were lungs (28%; 79% in hematology patients), rhinocerebral (25%; 64% in diabetic patients), skin (20%), and disseminated (18%). Median time between first symptoms and diagnosis was 2 weeks. The main fungal species were Rhizopus oryzae (32%) and Lichtheimia species (29%). In cases where the causative species was identified, R. oryzae was present in 85% of rhinocerebral forms compared with only 17% of nonrhinocerebral forms (P < .001). Treatment consisted of surgery in 59% and antifungals in 87% of cases (liposomal amphotericin B in 61%). Ninety-day survival was 56%; it was reduced in cases of dissemination compared with rhinocerebral (HR, 5.38 [2.0-14.1]; P < .001), pulmonary (HR, 2.2 [1.0-4.7]; P = .04), or skin localization (HR, 5.73 [1.9-17.5]; P = .002); survival was reduced in cases of hematological malignancies compared with diabetes mellitus (HR, 2.3 [1.0-5.2]; P < .05) or trauma (HR, 6.9 [1.6-28.6], P = .008) and if ≥2 underlying conditions (HR, 5.9 [1.8-19.0]; P = .004). Mucormycosis localization remained the only independent factor associated with survival. CONCLUSIONS This 3-year study performed in one country shows the diverse clinical presentation of mucormycosis with a high prevalence of primary skin infection following trauma and a prognosis significantly influenced by localization.

Cryptococcal cell morphology affects host cell interactions and pathogenicity.

Cryptococcus neoformans is a common life-threatening human fungal pathogen. The size of cryptococcal cells is typically 5 to 10 µm. Cell enlargement was observed in vivo, producing cells up to 100 µm. These morphological changes in cell size affected pathogenicity via reducing phagocytosis by host mononuclear cells, increasing resistance to oxidative and nitrosative stress, and correlated with reduced penetration of the central nervous system. Cell enlargement was stimulated by coinfection with strains of opposite mating type, and ste3 a Δ pheromone receptor mutant strains had reduced cell enlargement. Finally, analysis of DNA content in this novel cell type revealed that these enlarged cells were polyploid, uninucleate, and produced daughter cells in vivo. These results describe a novel mechanism by which C. neoformans evades host phagocytosis to allow survival of a subset of the population at early stages of infection. Thus, morphological changes play unique and specialized roles during infection.

Epidemiological trends in invasive aspergillosis in France: the SAIF network (2005–2007)

A prospective (2005-2007) hospital-based multicentre surveillance of EORTC/MSG-proven or probable invasive aspergillosis (IA) cases whatever the underlying diseases was implemented in 12 French academic hospitals. Admissions per hospital and transplantation procedures were obtained. Cox regression models were used to determine risk factors associated with the 12-week overall mortality. With 424 case-patients included, the median incidence/hospital was 0.271/10(3) admissions (range 0.072-0.910) without significant alteration of incidence and seasonality over time. Among the 393 adults (62% men, 56 years (16-84 years)), 15% had proven IA, 78% haematological conditions, and 92.9% had lung involvement. Acute leukaemia (34.6%) and allogeneic stem cell transplantation (21.4%) were major host factors, together with chronic lymphoproliferative disorders (21.6%), which emerged as a new high-risk group. The other risk host factors consisted of solid organ transplantation (8.7%), solid tumours (4.3%), systemic inflammatory diseases (4.6%) and chronic respiratory diseases (2.3%). Serum galactomannan tests were more often positive (≥69%) for acute leukaemia and allogeneic stem cell transplantation than for the others (<42%; p <10(-3)). When positive (n = 245), cultures mainly yielded Aspergillus fumigatus (79.7%). First-line antifungal therapy consisted of voriconazole, caspofungin, lipid formulations of amphotericin, or any combination therapy (52%, 14%, 8% and 19.9%, respectively). Twelve-week overall mortality was 44.8% (95% CI, 39.8-50.0); it was 41% when first-line therapy included voriconazole and 60% otherwise (p <0.001). Independent factors for 12-week mortality were older age, positivity for both culture and galactomannan and central nervous system or pleural involvement, while any strategy containing voriconazole was protective.

Epidemiology of HIV-associated cryptococcosis in France (1985-2001): comparison of the pre- and post-HAART eras.

Objective: To analyse the epidemiological evolution of cryptococcosis in France after the introduction of highly active antiretroviral therapy (HAART). Design: Retrospective study of cryptococcosis cases recorded at the National Reference Center for Mycoses in France since 1985. Methods: Using the national surveillance data, we reviewed 1644 cases of HIV-associated cryptococcosis diagnosed in France (population, 59 million) between 1985 and 2001 and compared them to 335 cases recorded in HIV-negative patients. Results: The total number of cryptococcosis cases evolved in parallel to that recorded for HIV-infected patients. Changes occurring after HAART introduction were analysed. A negative binomial regression model established a 46% decrease of the incidence of cryptococcosis during the post-HAART era (1997–2001, n = 292) compared to the pre-HAART era (1985–1996, n = 1352). According to multivariate analysis, African origin, older age, heterosexual HIV contamination, no previous AIDS-defining illness, and no previous HIV infection diagnosis were variables independently associated with an increased risk of cryptococcosis during the post-HAART era. During the same period, the characteristics of the HIV-negative population did not change. Conclusions: Our analysis of the national surveillance identified demographic factors associated with an increased risk of cryptococcosis in the post-HAART era suggesting that failure to consult and considering oneself not at risk were determinant in the current epidemiology of HIV-related cryptococcosis in France.