Clogmia albipunctata (Nematocera; Psychodidae) as the Etiologic Agent of Myiasis: True or False?

Clogmia albipunctata, known as drain fly, is a non-hematophagous insect of the Psychodidae family with worldwide distribution, particularly in tropical and temperate areas. It can be found near sewer drains, sewage treatment plants, plant pots, swamps, and any other place containing decaying or moist organic matter. It has been introduced in several publications as the causative agent of myiasis in humans. A case presentation, together with a compilation of findings from a database, including 51 scientific publications in the literature, allowed us to overview critically in detail the variable aspects of epidemiology, life cycle, biology, and medical importance of this insect and its probable role in human myiasis. The absence of a precise definition of myiasis and the lack of incontestable epidemiological, entomological, and clinical evidence in the articles introducing C. albipunctata as a causative agent led us to interrogate its role in human myiasis. It is necessary to take into account this misinterpretation and make an accurate diagnosis based on the isolation of insect larvae from the corresponding lesion.

Successful Treatment of Saksenaea sp. Osteomyelitis by Conservative Surgery and Intradiaphyseal Incorporation of Amphotericin B Cement Beads.

Osteoarticular mucormycosis cases are quite rare and challenging infections that are mostly due to direct inoculation during traumatic injury among immunocompetent patients. Classic management includes a combination of aggressive surgical debridement, which may lead to amputation, and long-term systemic liposomal amphotericin B therapy. This article describes the successful treatment of Saksenaea sp. osteomyelitis in a patient with diabetes mellitus, using a combination of systemic antifungal therapy and conservative surgery with insertion of amphotericin-impregnated cement beads.

Performance of Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry for Identifying Clinical Malassezia Isolates.

The genus Malassezia comprises commensal yeasts on human skin. These yeasts are involved in superficial infections but are also isolated in deeper infections, such as fungemia, particularly in certain at-risk patients, such as neonates or patients with parenteral nutrition catheters. Very little is known about Malassezia epidemiology and virulence. This is due mainly to the difficulty of distinguishing species. Currently, species identification is based on morphological and biochemical characteristics. Only molecular biology techniques identify species with certainty, but they are time-consuming and expensive. The aim of this study was to develop and evaluate a matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) database for identifying Malassezia species by mass spectrometry. Eighty-five Malassezia isolates from patients in three French university hospitals were investigated. Each strain was identified by internal transcribed spacer sequencing. Forty-five strains of the six species Malassezia furfur, M. sympodialis, M. slooffiae, M. globosa, M. restricta, and M. pachydermatis allowed the creation of a MALDI-TOF database. Forty other strains were used to test this database. All strains were identified by our Malassezia database with log scores of >2.0, according to the manufacturer's criteria. Repeatability and reproducibility tests showed a coefficient of variation of the log score values of <10%. In conclusion, our new Malassezia database allows easy, fast, and reliable identification of Malassezia species. Implementation of this database will contribute to a better, more rapid identification of Malassezia species and will be helpful in gaining a better understanding of their epidemiology.

Recurrent episodes of Candidemia due to Candida glabrata, Candida tropicalis and Candida albicans with acquired echinocandin resistance.

Mixed fungal infection and acquired echinocandin resistance of Candida spp. remain infrequent. In this study we have reported the case of a patient hospitalized for tuberculosis who experienced multiple infections due to three common Candida species (C. albicans, C. glabrata, C. tropicalis). Furthermore, consecutive isolates from blood cultures and heart valve were found resistant to azoles (C. tropicalis) and to echinocandin with either novel (C. tropicalis) or previously described (C. albicans) missense mutations in the Fks gene.

Fungi, Water Supply and Biofilms.

Even though it has been studied for many years, water-related infectious risk still exists in both care and community environments due to the possible presence of numerous microorganisms such as bacteria, fungi and protists. People can be exposed directly to these microorganisms either through aerosols and water, after ingestion, inhalation, skin contact and entry through mucosal membranes, or indirectly usually due to pre-treatment of some medical devices. Species belonging to genera such as Aspergillus, Penicillium, Pseudallesheria, Fusarium, Cuninghamella, Mucor and in some particular cases Candida have been isolated in water from health facilities and their presence is particularly related to the unavoidable formation of a polymicrobial biofilm in waterlines. Fungi isolation methods are based on water filtration combined with conventional microbiology cultures and/or molecular approaches; unfortunately, these are still poorly standardized. Moreover, due to inappropriate culture media and inadequate sampling volumes, the current standardized methods used for bacterial research are not suitable for fungal search. In order to prevent water-related fungal risk, health facilities have implemented measures such as ultraviolet radiation to treat the input network, continuous chemical treatment, chemical or thermal shock treatments, or microfiltration at points of use. This article aims to provide an overview of fungal colonization of water (especially in hospitals), involvement of biofilms that develop in waterlines and application of preventive strategies.

Diagnosis of dermatophytosis: an evaluation of direct examination using MycetColor® and MycetFluo®.

Dermatophytes are an important cause of superficial fungal infection. Direct examination of skin, nail, or hair samples remains essential in diagnosis, as it provides a quick response to the clinician. However, mycological analysis, including direct examination and culture, often lacks sensitivity. The use of stains or fluorochromes may enhance the performance of direct examination. We analyzed 102 samples from patients with suspected dermatophytosis in 4 different diagnostic mycology laboratories. Two reagents, MycetColor® and MycetFluo®, which use Congo red and calcofluor dye, respectively, were evaluated for the direct microscopic examination of skin, hair, and nail specimens. The results were compared to those of culture and conventional direct examination. Both reagents were able to clarify the specimens and also to specifically stain fungal elements. Microscopic examination of the specimens was greatly facilitated with MycetFluo®, which allowed a higher number of positive cases to be detected compared to the other methods.

Pneumocystis jirovecii pneumonia in HIV-negative patients: a prospective study with focus on immunosuppressive drugs and markers of immune impairment.

Pneumocystis jirovecii pneumonia (PCP) is emerging in HIV-negative patients, for whom the prognosis is significantly worse than in HIV-infected patients and risk factors are poorly characterized. We performed an observational, multi-centre, prospective study of 56 consecutive cases of documented PCP in HIV-negative patients, and found that: (1) the main underlying conditions were haematological malignancies (43%), solid tumours (25%), inflammatory diseases (20%), and solid organ transplantation (7%); (2) most patients (80%) had received prolonged corticosteroids, with a mean daily dose of 47.3 ± 32.8 mg equivalent prednisone when PCP was diagnosed, and a mean cumulative dose of 5807 ± 5048 mg over the last 12 months; and (3) the median CD4 cell count was 0.12 × 109/l (range 0.0-1.42), with a median CD4/CD8 ratio of 1.32 (0.0-6.4). These findings may be used to better target PCP prophylaxis according to the level of risk and contribute to decrease the burden of PCP in HIV-negative patients.

Impact of yeast-bacteria coinfection on the detection of Candida sp. in an automated blood culture system.

Invasive candidiasis remains a major cause of morbidity and mortality. It is now well known that an early diagnosis contributes to the patients' outcome. Blood cultures, which are the first-line test in case of bloodstream infection suspicion, can be carried out using fungus-selective medium (containing antibiotics) or standard microorganism medium allowing both bacterial and fungal growth. Some patients can suffer from polymicrobial sepsis involving bacteria and yeasts, so we decided to investigate in blood cultures the influence of the presence of bacteria on fungal development. Simulated blood cultures were performed using Candida albicans or C. glabrata coincubated with Escherichia coli or Staphylococcus aureus at different concentrations. The results showed that, in a standard microorganism medium, bacterial growth could hide the fungal development. Thus, in patients at risk of invasive candidiasis, the use of a specific fungal medium could improve the diagnosis and allow an earlier efficient antifungal treatment.

Breakthrough invasive mould infections in patients treated with caspofungin.

OBJECTIVES: To describe and estimate the rate of breakthrough invasive mould diseases (IMD) in patients receiving caspofungin. METHODS: Retrospective, non-interventional study conducted in three University Hospitals. RESULTS: Nineteen breakthrough infections have been identified including 13 aspergillosis, 2 mucormycosis, a fusariosis, a Hormographiella aspergillata infection and 2 possible IMD. Cases were equally distributed between the centres. Fourteen patients had a haematologic malignancy, four were transplant recipients (allogeneic haematopoietic stem cells in three, liver in one) and one had hepatic cirrhosis. Caspofungin has been prescribed as prophylaxis (n = 3), empirical therapy (n = 9) or directed therapy for candidemia (n = 5) or aspergillosis (n = 2). Aspergillus galactomannan was positive in serum or in bronchoalveolar lavage fluid in 10 of the 13 aspergillosis. Median duration of caspofungin treatment before breakthrough IMD was 15 days. Nine patients died within twelve weeks. Rate of breakthrough IMD in onco-haematology patients has been estimated to 7.3% for all mould infections and to 4.2% when restricted to documented aspergillosis. CONCLUSIONS: Our data call for Aspergillus galactomannan monitoring and close clinical and radiological examination in case of persistence or recurrence of infection signs in high-risk patients receiving caspofungin.

Breakthrough Hormographiella aspergillata infections arising in neutropenic patients treated empirically with caspofungin.

Hormographiella aspergillata, a filamentous basidiomycete, has rarely been involved in human infections. We describe 2 febrile neutropenic patients who developed a severe pulmonary infection due to H. aspergillata while receiving empirical caspofungin therapy for presumed fungal pneumonia. After introduction of liposomal amphotericin B, one patient, who had neutrophil recovery, presented a favorable outcome, while the other, who remained neutropenic throughout the course of infection, died. Resistant fungi, including basidiomycetes, may emerge during empirical treatment with caspofungin in febrile neutropenic patients. A rapid switch to any other potent antifungal should be rapidly considered in case of failure of caspofungin in this setting.

In vivo biofilm composition of Aspergillus fumigatus.

The in vivo composition of the mycelial extracellular matrix (ECM) of Aspergillus fumigatus during host invasion is reported here for the first time. A new galactosaminogalactan and the galactomannan were the major polysaccharides of the in vivo ECM. The composition of the ECM in vivo varied with the aspergillosis pathologies.

Fungal rhinosinusitis: a categorization and definitional schema addressing current controversies.

BACKGROUND: Fungal (rhino-) sinusitis encompasses a wide spectrum of immune and pathological responses, including invasive, chronic, granulomatous, and allergic disease. However, consensus on terminology, pathogenesis, and optimal management is lacking. The International Society for Human and Animal Mycology convened a working group to attempt consensus on terminology and disease classification. DISCUSSION: Key conclusions reached were: rhinosinusitis is preferred to sinusitis; acute invasive fungal rhinosinusitis is preferred to fulminant, or necrotizing and should refer to disease of <4 weeks duration in immunocompromised patients; both chronic invasive rhinosinusitis and granulomatous rhinosinusitis were useful terms encompassing locally invasive disease over at least 3 months duration, with differing pathology and clinical settings; fungal ball of the sinus is preferred to either mycetoma or aspergilloma of the sinuses; localized fungal colonization of nasal or paranasal mucosa should be introduced to refer to localized infection visualized endoscopically; eosinophilic mucin is preferred to allergic mucin; and allergic fungal rhinosinusitis (AFRS), eosinophilic fungal rhinosinusitis, and eosinophilic mucin rhinosinusitis (EMRS) are imprecise and require better definition. In particular, to implicate fungi (as in AFRS and EMRS), hyphae must be visualized in eosinophilic mucin, but this is often not processed or examined carefully enough by histologists, reducing the universality of the disease classification. A schema for subclassifying these entities, including aspirin-exacerbated rhinosinusitis, is proposed allowing an overlap in histopathological features, and with granulomatous, chronic invasive, and other forms of rhinosinusitis. Recommendations for future research avenues were also identified.

Genotype of 88 Toxoplasma gondii isolates associated with toxoplasmosis in immunocompromised patients and correlation with clinical findings.

We report the genotyping analysis of Toxoplasma gondii isolates in samples collected from 88 immunocompromised patients, along with clinical and epidemiological data. Most of these samples were collected in France during the current decade by the Toxoplasma Biological Resource Center. Lack of specific anti-Toxoplasma treatment, pulmonary toxoplasmosis, and involvement of multiple organs were the 3 main risk factors associated with death for this patient group. Genotyping results with 6 microsatellite markers showed that type II isolates were predominant among patients who acquired toxoplasmic infection in Europe. Non-type II isolates included 13 different genotypes and were mainly collected from patients who acquired toxoplasmosis outside Europe. Type III was the second most common genotype recovered from patients, whereas type I was rare in our population. Three nonarchetypal genotypes were repeatedly recovered from different patients who acquired the infection in sub-Saharan Africa (genotypes Africa 1 and Africa 2) and in the French West Indies (genotype Caribbean 1). The distribution of genotypes (type II vs. non-type II) was not significantly different when patients were stratified by underlying cause of immunosuppression, site of infection, or outcome. We conclude that in immunocompromised patients, host factors are much more involved than parasite factors in patients' resistance or susceptibility to toxoplasmosis.

Relationships between free living amoebae and Exophiala dermatitidis: a preliminary study.

Free living amoebae can play a role as reservoirs for pathogens isolated from hospital water. We have investigated the potential interactions between two protozoa (Acanthamoeba castellanii and Hartmanella vermiformis) that may be recovered from hospital water tips and Exophiala dermatitidis, a black yeast often recovered from water sources. We showed that the presence of trophozoites or supernatants of culture of H. vermiformis increased fungal growth, whereas the same phenomenon was observed only with the supernatant of A. castellanii cultures. These preliminary results highlight the fact that the recovering of free-living amoebae in hospital water taps could lead to the development of fungal nosocomial pathogens.

[Prevention of fungal infections related to the water supply in French hospitals: proposal for standardization of methods]. / Surveillance mycologique de l'eau pour la prévention des mycoses invasives dans les établissements de santé: propositions de standardisation des méthodologies.

OBJECTIVES: The aims of this study were to assess the risk of fungal infections related to the water supply in several hospitals and to clarify the appropriate methodology in order to standardize the technical conditions of the controls and develop guidelines. It was conducted in 10 university hospital centers across the country from February 2004 through March 2005. METHOD: A preliminary study allowed us to optimize the mycological analysis. The study was conducted under the same conditions as for bacteriological controls: water filtration through a cellulose acetate membrane cultured on agar. Departments with the highest patient risk were selected, including hematology, organ transplantation, and burn units. We selected 98 sites and sampled both water and water-related surfaces at each: three one-liter water samples (the first flow, cold and hot water) and two or three surface samples (inside the tap, pommel of the shower and siphon). At each site, a form was filled to specify its location in the unit, any water treatment (chlorine or other), filtering, and temperature. Water from taps equipped with sterilized filtration was sampled without the filter. RESULTS: There was a significant difference (p=0.039) in the number of positive cultures between the three types of water sampled: hot water (>50 degrees C) was colonized less often than first flow or cold water. Only 4% of the hot-water samples had positive cultures, compared to the 52% of the cold-water samples. Except in two hospitals with generalized contamination of the water pipes (one with Exophiala spp and the other with Fusarium spp), colonization was usually slight. Cold water was more colonized than hot water, but 79% of the samples yielded fewer than 5CFU/L. Dematiaceous hyphomycetes were isolated; Aspergillus spp were rare. The number of CFU in surface samples (that is, biofilms) was higher (mean=15 CFU per sample) but surfaces were positive less often than water (13% compared with 43% of all water samples). Sampling from siphons was productive more often than from taps (23%), but the molds isolated differed from those in the related water. Relations to bacterial flora and P. aeruginosa were also studied, together with the effects of chemical treatment. CONCLUSION: Current regulations require only bacteriological survey. The absence of knowledge about the threshold of contamination at which there is a risk of nosocomial invasive fungal infections makes it difficult to impose routine monitoring. Mycological surveys of water are required during hospital renovation, plumbing work, pipe maintenance and when air samples are negative during nosocomial infection investigations.

Phylogenetic analysis of Trichophyton mentagrophytes human and animal isolates based on MnSOD and ITS sequence comparison.

Dermatophytes are keratinophilic fungi able to infect keratinized tissues of human or animal origin. Among them, Trichophyton mentagrophytes is known to be a species complex composed of several species or variants, which occur in both human and animals. Since the T. mentagrophytes complex includes both anthropophilic and zoophilic pathogens, accurate molecular identification is a critical issue for comprehensive understanding of the clinical and epidemiological implications of the genetic heterogeneity of this complex. Here, 41 T. mentagrophytes isolates from either human patients (14 isolates) or animals (27 isolates) with dermatophytosis were prospectively isolated by culture and identified on morphological bases at the University Hospital Centres of Lille and Poitiers, and the Veterinary School of Alfort, respectively. The isolates were differentiated by DNA sequencing of the variable internal transcribed spacer (ITS) regions flanking the 5.8S rDNA, and of the housekeeping gene encoding the manganese-containing superoxide dismutase (MnSOD), an enzyme which is involved in defence against oxidative stress and has previously provided interesting insight into both fungal taxonomy and phylogeny. ITS1-ITS2 regions and MnSOD sequences successfully differentiate between members of the T. mentagrophytes complex and the related species Trichophyton rubrum. Whatever the phylogenetic marker used, members of this complex were classified into two major clades exhibiting a similar topology, with a higher variability when the ITS marker was used. Relationships between ITS/MnSOD sequences and host origin, clinical pattern and phenotypic characteristics (macroscopic and microscopic morphologies) were analysed.

Effect of azoles on the secretion of a Candida albicans metallopeptidase.

Azole antifungals act by inhibiting the activity of a lanosterol demethylase involved in the generation of the ergosterol of the cellular membrane of fungi. These drugs could also have action on other yeast components, like secreted aspartyl proteases. We demonstrate in this study that the in vitro secretion of a metallopeptidase could be modified during the growth of Candida albicans with subinhibitory concentrations of some azoles. Eight isolates of this yeast have been cultivated in presence of MIC, MIC/2 and MIC/4 of voriconazole, fluconazole and itraconazole. The presence of voriconazole and fluconazole decreased the secretion of the metallopeptidase in the culture medium, whereas itraconazole increased this secretion for three isolates. This study points to the fact that some antifungals, given in prophylaxis, could act in an unfavourable way on some potential factors of pathogenicity.

Paranasal sinus fungus ball and surgery: a review of 175 cases.

OBJECTIVE: To analyze the surgical results after Functional Endoscopic Sinus Surgery (FESS) in patients with paranasal sinus fungus ball. MATERIAL AND METHODS: Retrospective analysis of the results of FESS performed in 175 patients suffering from paranasal sinus fungus balls. RESULTS: All maxillary (n = 150), sphenoidal (n = 20), and ethmoidal (n = 4) locations have been treated exclusively by FESS to obtain a wide opening of the affected sinuses, allowing a careful extraction of all fungal material without removal of the inflamed mucous membrane. No major complication occurred. Postoperative care was reduced to nasal lavage with topical steroids for 3 to 6 weeks. Only 1 case of local failure have been observed (maxillary sinus, n = 1), and 6 cases of persisting of fungus ball (maxillary sinus, n = 4; frontal sinus, n = 2) with a mean follow-up of 5 years. No medical treatment (antibiotic, antifungal) was required. CONCLUSION: Surgical treatment of a fungus ball consists in opening the infected sinus cavity at the level of its ostium and removing fungal concretions while sparing the normal mucosa. No antifungal therapy is required. Finally, through this 175 patients study, FESS appears a reliable and safe surgical treatment with a low morbidity.