Unexpected mould diversity in clinical isolates from French Guiana and associated identification difficulties.

New mold species are increasingly reported in invasive fungal infections. However, these fungi are often misdiagnosed or undiagnosed due to the use of inappropriate laboratory diagnostic tools. Tropical countries, such as French Guiana, harbor a vast diversity of environmental fungi representing a potential source of emerging pathogens. To assess the impact of this diversity on the accuracy of mold-infection diagnoses, we identified mold clinical isolates in French Guiana during a five-month follow-up using both microscopy and matrix-assisted laser desorption ionization time-of-flight mass spectrometry. In total, 38.8% of the 98 obtained molds isolates could not be identified and required a DNA-based identification. Fungal diversity was high, including 46 species, 26 genera, and 13 orders. Fungal ecology was unusual, as Aspergillus species accounted for only 27% of all isolates, and the Nigri section was the most abundant out of the six detected Aspergillus sections. Macromycetes (orders Agaricales, Polyporales, and Russulales) and endophytic fungi accounted for respectively 11% and 14% of all isolates. Thus, in tropical areas with high fungal diversity, such as French Guiana, routine mold identification tools are inadequate. Molecular identifications, as well as morphological descriptions, are necessary for the construction of region-specific mass spectrum databases. These advances will improve the diagnosis and clinical management of new fungal infections. LAY SUMMARY: In French Guiana, environmental fungal diversity may be a source of emerging pathogens. We evaluated microscopy and mass spectrometry to identify mold clinical isolates. With 39% of unidentified isolates, a region-specific mass spectrum database would improve the diagnosis of new fungal infections.

Actinomycetoma caused by Gordonia westfalica: first reported case of human infection.

Bacteria of the genus Gordonia are rarely involved in human infections. We report here the case of a 30-year-old man from Guinea Buissau with mycetoma of the foot. 16S DNA sequencing after surgical biopsy identified Gordonia westfalica. To our knowledge, this is the first report of human infection caused by G. westfalica.

An atypical keloid in a Brazilian man.

Case report from French Guiana of an atypical keloid in a Brazilian man: Lobomycosis. Lobomycosis is a rare fungal skin infection, endemic to the Amazon basin. Its clinical manifestations are slow-growing keloid-like nodules, with a granulomatous reaction on histopathology. The etiological agent, Lacazia loboi, has never been isolated in the environment or cultured in a laboratory. Diagnosis is based on the typical appearance on microscopy. Treatment is disappointing, with a high recurrence rate. We report a new case in French Guiana and review the literature. Only 10 cases have been reported outside of the endemic area, 2 involving no travel; the mean time to diagnosis was 21 years. Phylogenetic analysis has recently proved that lobomycosis in dolphins is caused by a fungus more closely related to Paracoccidioides brasiliensis than to L. loboi (two very closely related species). Molecular diagnosis is possible in a few centers. Climate change may result in spreading lobomycosis to currently disease-free areas of the world.

Histoplasma capsulatum causing sinusitis: a case report in French Guiana and review of the literature.

BACKGROUND: American histoplasmosis is a mycosis caused by Histoplasma capsulatum. A variety of clinical features of histoplasmosis have been commonly described ranging from asymptomatic infections to severe pulmonary infections. In immunocompromised individuals, progressive disseminated forms are frequent, leading to fatal outcome if untreated. However, H. capsulatum sinusitis is unusual with a few cases documented over the last three decades and may be underdiagnosed or confused with other fungal aetiologies, especially outside endemic regions. CASE PRESENTATION: In this study, we report an atypical case of Histoplasma capsulatum sinus fungus ball-like in a patient with Acquired Immunodeficiency Syndrome due to Human Immunodeficiency Virus complicated by a disseminated histoplasmosis with a death ending. Diagnosis relied on CT-Scan imaging and on both direct examination of H. capsulatum yeast forms (Gomory methenamine Grocott) in the sinus specimen (aspirate, biopsy) and on positivity of the culture further confirmed by qPCR. CONCLUSIONS: Since last few decades, among the eight reviewed patients, H. capsulatum sinusitis occurred mostly in HIV-immunocompromised patients and for three cases as a sinusitis with disseminated histoplasmosis. Even if this is a rare clinical presentation, its diagnosis is crucial as it could represent an early expression of an Histoplasma capsulatum exposure that can evolve into a disseminated fatal infection when immunity decreases.

Predictors of antimalarial self-medication in illegal gold miners in French Guiana: a pathway towards artemisinin resistance.

BACKGROUND: Malaria is endemic in French Guiana (FG), South America. Despite the decrease in cases in the local population, illegal gold miners are very affected by malaria (22.3% of them carried Plasmodium spp.). Self-medication seems to be very common, but its modalities and associated factors have not been studied. The aim of this study was to evaluate parasite susceptibility to drugs and to document behaviours that could contribute to resistance selection in illegal gold miners. METHODS: This multicentric cross-sectional study was conducted in resting sites along the FG-Surinamese border. Participating gold miners working in FG completed a questionnaire and provided a blood sample. RESULTS: From January to June 2015, 421 illegal gold miners were included. Most were Brazilian (93.8%) and 70.5% were male. During the most recent malaria attack, 45.5% reported having been tested for malaria and 52.4% self-medicated, mainly with artemisinin derivatives (90%). Being in FG during the last malaria attack was the main factor associated with self-medication (adjusted OR = 22.1). This suggests that access to malaria diagnosis in FG is particularly difficult for Brazilian illegal gold miners. Treatment adherence was better for persons who reported being tested. None of the 32 samples with Plasmodium falciparum presented any mutation on the pfK13 gene, but one isolate showed a resistance profile to artemisinin derivatives in vitro. CONCLUSIONS: The risk factors for the selection of resistance are well known and this study showed that they are present in FG with persons who self-medicated with poor adherence. Interventions should be implemented among this specific population to avoid the emergence of artemisinin resistance.

[Paracoccidioidomycosis of the external ear]. / Paracoccidioïdomycose localisée au pavillon d'une oreille.

BACKGROUND: Paracoccidioidomycosis is a systemic fungal infection common in Latin America. Cutaneous involvement is frequent and usually affects multiple sites, being most frequently associated with lesions of the oropharyngeal mucosa. The cutaneous form on its own is rare. PATIENTS AND METHODS: We report a case of paracoccidioidomycosis isolated from the ear of a 43-year-old immunocompetent man. The lesion consisted of a partially ulcerated plaque on the auricle of the left ear. Direct examination, histopathological examination and PCR revealed the presence in the skin lesion of yeasts identified as Paracoccidioides brasiliensis. DISCUSSION: The sites of paracoccidioidomycosis on the ear can be confused with other tropical diseases frequently found in the Amazon region such as leishmaniasis, leprosy and lobomycosis. The absence of any other cutaneous sites in this case raised the question of whether the lesion was of primary or secondary origin.

[Chagas disease (American trypanosomiasis) in France]. / La maladie de Chagas (ou trypanosomose américaine) en France.

Chagas disease is an anthropozoonotic infection caused by Trypanosoma cruzi, transmitted by a hematophagous triatomine insect vector belonging to the Reduviidae family, while taking a blood meal. There is a large reservoir of wild and domestic mammals. Human contamination may come via vectorial, transplacental, and digestive routes, blood transfusion, organ or tissue transplantation, and by accident. The disease has two phases. The acute phase, oligosymptomatic, is frequently undiagnosed. It is followed by a chronic phase. Most of the infected patients remain asymptomatic all life-long. But 10 or 25 years later, one third of infected patients present with cardiac or digestive complications. Chagas disease is endemic in Latin America, from Mexico to Argentina. In French Guyana, the prevalence of the infection was estimated at 0.25% and 0.5% (from 500 to 1000 infected patients) on blood samples collected from 1992 to 1998. In 2000 and 2009, 192 cases were diagnosed. In this district, there is no established domestic vector and the transmission risk is low. The vector is very easily found in forest habitats and even in the peridomestic persistent forest, with an infection rate of 46 to 86%. Vectorial eradication is impossible. Fighting against Chagas disease in French Guyana relies more on individual protection, control of blood transfusion, prevention of mother-to-child transmission, diagnosis, and treatment of infected patients than on vectorial control.

Fatal histoplasmosis in a non-HIV patient in French Guiana.

Histoplasmosis is an endemic fungal infection that causes no symptoms or minor self-limited illnesses in most cases. Severe forms are commonly reported in patients with immunodeficiency disorders; histoplasmosis is considered to be an opportunistic infection in patients with AIDS. We report a case of disseminated histoplasmosis in a patient with no induced active suppression of the immune response. The infection was fulminant, and antifungal treatment was delayed because of a misdiagnosis of tuberculosis.

Eumycetoma caused by Diaporthe phaseolorum (Phomopsis phaseoli): a case report and a mini-review of Diaporthe/Phomopsis spp invasive infections in humans.

Diaporthe phaseolorum (syn. Phomopsis phaseoli) is a frequent fungal parasite of plants, present on all continents around the world. It has rarely been involved in human diseases. We report a case of eumycetoma with osteomyelitis of the forefoot caused by this fungus and diagnosed by molecular biology. The patient had positive HTLV-1 serology and was a farmer from French Guiana who walked barefoot. He was successfully treated with long-term oral itraconazole (400 mg/day). A review of the literature underlines the essential roles of plants and host immunosuppression in this infection and the favourable outcome with a triazole antifungal treatment.

Human impact on genetic diversity of Toxoplasma gondii: example of the anthropized environment from French Guiana.

In French Guiana, severe cases of toxoplasmosis in immunocompetent patients are associated with atypical strains of Toxoplasma gondii linked to a wild neotropical rainforest cycle and a higher genetic diversity than usually observed for T. gondii isolates from anthropized environment. This raises the question of the impact of anthropization of the natural environment, on genetic diversity and on the population structure of T. gondii. However, few data are available on strains circulating in the anthropized areas from French Guiana. Seropositive animals originating mainly from anthropized sub-urban areas and punctually from wild environment in French Guiana were analyzed for T. gondii isolation and genotyping. Thirty-three strains were obtained by bioassay in mice and compared with 18 previously reported isolates chiefly originating from the Amazon rainforest. The genotyping analysis performed with 15 microsatellite markers located on 12 different chromosomes revealed a lower genetic diversity in the anthropized environment. Results were analyzed in terms of population structure by clustering methods, Neighbor-joining trees reconstruction based on genetic distances, F(ST,) Mantel's tests and linkage disequilibrium. They clearly showed a genetic differentiation between strains associated to the anthropized environment and those associated to the wild, but with some inbreeding between them. The majority of strains from the anthropized environment were clustered into additional lineages of T. gondii that are common in the Caribbean. In conclusion the two environmental populations "wild" and "anthropized" were genetically well differentiated. The anthropization of the environment seems to be accompanied with a decreased diversity of T. gondii associated with a greater structure of the populations. We detected potential interpenetration and genetic exchanges between these two environmental populations. As a higher pathogenicity in human of "wild" genotypes has been described, the interpenetration of both environments leads to hybridization between strains that may be at risk for human health.

[Mucocutaneous leishmaniasis due to Leishmania guyanensis: a case report in an HIV-infected patient]. / Leishmaniose cutanéo-muqueuse à Leishmania guyanensis: une observation chez un patient infecté par le VIH.

In French Guiana cutaneous leishmaniasis occurs mainly in the localized form with L. guyanensis accounting for more than 90% of cases. Mucocutaneous leishmaniasis is uncommon (less than 2% of cases) with L. braziliensis accounting for all previously reported cases. The purpose of this report is to describe a case of mucocutaneous leishmaniasis due to L. guyanensis that led to diagnosis of HIV infection in a patient living in French Guiana.

[Cardiac troponin I and CK-MB mass after cardiac surgery with cardiopulmonary bypass]. / Troponine Ic et CK-MB masse en chirurgie cardiaque sous circulation extracorporelle.

Cardiac troponin I (cTnI) assay is used in the diagnosis of myocardial infarction after cardiac surgery. Variations in the cut-off value have been reported even with the same assay method. The aim of this work is to investigate the release profile of cTnI and CK-MB mass after cardiac surgery and to determine the cut-off value of cTnI and CK-MB mass allowing the diagnosis of perioperative myocardial infarction. In patients without postoperative cardiac complication, the cTnI peak was observed 24 hours after surgery both in coronary artery bypass grafting and in valve replacement. Moreover, the amount of cTnI released within the three hours after surgery is 2.5 fold higher in valve replacement than in coronary artery bypass grafting. The CK-MB peak was observed 3 hours after surgery in the two surgical procedures. In these patients, cTnI and CK-MB concentrations increased with the cross clamp time duration. In patients with postoperative myocardial infarction, the cTnI and CK-MB peaks were observed 24 hours after surgery. Diagnosis of perioperative myocardial infarction can be performed with a sensitivity of 100% at 24 hours with cut-off values of 32 and 7 microg/L for CK-MB and cTnI, respectively, both with Stratus (Dade Behring) and Immulite (DPC) analysers.

Efficiency of defined strains and of soil consortia in the biodegradation of polycyclic aromatic hydrocarbon (PAH) mixtures.

The microbiological characteristics of the bacterial degradation of mixtures of five polycyclic aromatic hydrocarbons (PAH), phenanthrene, fluorene, anthracene, fluoranthene and pyrene, were investigated. Three pure bacterial strains using one or several of these PAH as carbon sources were selected. The interactions between PAH during the degradation of PAH pairs by each of these strains were studied and their effects on the kinetics and the balance of degradation were characterised. Competition between PAH and degradation by cometabolism were frequently observed. Mixed cultures of two or three strains, although possessing the global capacity to mineralise the set of five PAH, achieved limited degradation of the mixture. In contrast, a consortium from a PAH-contaminated soil readily mineralised the five-PAH mixture. The results suggested that soil consortia possessed a wider variety of strains capable to compensate for the competitive inhibition between PAH as well as specialised strains that mineralised potentially inhibitory PAH metabolites produced by cometabolism.

Intrinsic capacities of soil microflorae for gasoline degradation.

A methodology to determine the intrinsic capacities of a microflora to degrade gasoline was developed, in particular for assessing the potential of autochtonous populations of polluted and non polluted soils for natural attenuation and engineered bioremediation. A model mixture (GM23) constituted of the 23 most representative hydrocarbons of a commercial gasoline was used. The capacities of the microflorae (kinetics and extent of biodegradation) were assessed by chromatographic analysis of hydrocarbon consumption and of CO2 production. The degradation of the components of GM23 was assayed in separate incubations of each component and in the complete mixture. For the microflora of an unpolluted spruce forest soil, all hydrocarbons of GM23 except cyclohexane, 2,2,4- and 2,3,4-trimethylpentane isomers were degraded to below detection limit in 28 days. This microflora was reinforced with two mixed microbial communities selected from gasoline-polluted sites and shown to degrade cyclohexane and 2,2,4-trimethylpentane. With the reinforced microflora, complete degradation of GM23 was observed. The degradation patterns of individual components of GM23 were similar when the compounds were present individually or in the GM23 mixture, as long as the concentrations of 2-ethyltoluene and trimethylbenzene isomers were kept sufficiently low (< or = 35 mg.l-1) to remain below their inhibitory level.

Nonlinear demographic models and chaotic demo-dynamics.

PIP: "Linear models derived from stable population theory still remain a basic reference, but it is clear that non linear models offer much more possibilities to account for actual demographic or demo-economic dynamics. On the other hand, there is one aspect of non linear models which has been probably overemphasized over the last [few] years, which is their ability to generate chaotic dynamics. Up to now, models which have been proposed have some difficulties in deriving such a behavior from plausible assumptions concerning demographic behavior or demo-economic relationships. We illustrate this point of view by discussing two examples, borrowed respectively from Day (1984) and Prskawetz/Feichtinger (1995)." (EXCERPT)^ieng

Kinetic studies of biodegradation of insoluble compounds by continuous determination of oxygen consumption.

Continuous determination of oxygen consumption by electrolytic respirometry has been experimented as a means to study the biodegradation kinetics of scarcely soluble environmental pollutants. The substrates used were the polycyclic aromatic hydrocarbons (PAH), naphthalene, phenanthrene, anthracene, fluoranthene and pyrene. The definition of an appropriate mode of PAH supply, either as crystals or more generally as a solution in a water non-miscible solvent, was found essential for yielding reproducible biodegradation kinetics. In these conditions, for all compounds tested, oxygen determination was found suitable for quantitative evaluation of PAH biodegradation and formation of biomass and soluble metabolites. The study of biodegradation kinetics with this methodology showed that a first phase of exponential growth could be characterized in most cases, followed by a phase of limited growth. Possible mechanisms involved in insoluble substrate uptake are discussed. During exponential growth, the bacteria utilized (although not necessarily exclusively) the PAH solubilized in the aqueous medium.

[Work after age 55: recent trends and forecast elements]. / L'activite apres 55 ans: evolutions recentes et elements de prospective.

Labor force participation in France of those aged over 55 years is analyzed in this article. "The drop in the participation rate in later years is a longterm trend found in most developed countries. It is a common method for reducing working hours over an entire life cycle and has been made possible by the growth in productivity and the development of pension schemes. However, the phenomenon grew in the mid-1970s, especially in France, due to the growth in early retirement and end-of-career unemployment and also the lowering of the legal retirement age. The participation rate in France is now very low after sixty and is one of the lowest in Europe for the 55-to-59-year-old age bracket." (SUMMARY IN ENG AND GER AND SPA)

[Is the rise in the female participation rate linked to fertility rate trends?]. / Hausse de l'activite feminine: quels liens avec l'evolution de la fecondite?

PIP: France's total fertility rate declined from 2.9 in 1964 to 1.8-1.9 in 1975 and to 1.65-1.7 currently, while the activity rate for women 25-49 years old increased from 42% to 80% in the same period. The decline of fertility at a time of increased female labor force participation has led to questions regarding causality. Whether the association is purely a result of coincidence or whether it reflects a causal relation in one direction or the other is not known. This work proposes a simple model to study interdependence that does not assume either that the decline of large families led to increased participation rates, or that the increasing desire of women to work led to smaller families. The log linear model utilized was applied to data from 5 censuses for the years 1962, 1968, 1975, 1982, and 1990. Women 35-39 years old were studied on the assumption that their activity rates would represent choices over the life cycle, and that their families would be nearly complete. The three model parameters can be interpreted as a preference for activity over inactivity (whether or not the need for a second paycheck was a factor in the decision to work), a preference for large families, and the degree of incompatibility between economic activity and motherhood. The results indicate that family sizes larger than two children were a minority preference in all periods studied, and that the intensity of incompatibility between work and having children has varied only slightly. The preference for work has on the other hand increased rapidly. This finding is consistent with the steep rise observed in female activity rates for all family sizes.^ieng

The microbiological fate of polycyclic aromatic hydrocarbons: carbon and oxygen balances for bacterial degradation of model compounds.

A series of pure bacterial strains belonging mainly to the Rhodococcus and Pseudomonas genera were grown on one of the following polycyclic aromatic hydrocarbons (PAH) supplied as sole carbon and energy source; naphthalene, fluorene, phenanthrene, anthracene, fluoranthene and pyrene. In each case, a quantitative evaluation of the carbon repartition of the PAH degraded into CO2, biomass and water-soluble metabolites was carried out. In addition, the kinetics of oxygen consumption and of water-soluble metabolite accumulation during PAH biodegradation was followed with respirometric equipment. Satisfactory carbon balances were obtained and the data correlated well with oxygen consumption values. The results show that growth on PAH presents high mineralization yields (from 56% to 77% of carbon) and sizeable production of biomass (from 16% to 35% of carbon) and limited but significant accumulation of metabolites (from 5% to 23% of carbon). The mineralization yields were higher and biomass yields lower in the case of higher PAH. Some differences between strains were also observed.