[Importance of a regional observatory of malarial chemoresistance, an emerging public health problem in the Guyanas region]. / Intérêt d'un observatoire régional de la chimiorésistance du paludisme, problème émergent de santé publique dans la région des Guyanes.

A regular implementation of prophylactic and therapeutic decision trees was organized on a consensus basis in Cayenne, French Guiana in 1990, 1995 and 2002. The updated recommendations were based on the knowledge of the in vitro chemosensitivity profiles of the local isolates, mainly coming from big rivers (Maroni and Oyapock, frontiers with Suriname and Brazil, respectively; and more recently Approuague). Most of the patients infected by Plasmodium falciparum were followed by the medical staff of the main hospitals (Cayenne and Saint-Laurent) and of the peripheral health centers in remote areas. Consequently the epidemiological situation and evolution of chemoresistance have been widely observed on a long-term (since 1994) basis in the Maroni region. Yet, we have only partial information coming from the Oyapock valley, even though an important (most of the time) illegal immigration has been developing since the 90s' leading to a notable modification of the epidemiological status of malaria in this eastern region, including a regular increase of P. vivax infections. Presently very little P. vivax chloroquine (and mefloquine) resistance has been identified but this result could lead to a real public health problem in a near future. As such, the National Reference Center on Plasmodium Chemoresistance in the French West Indies and Guiana (CNRCP-AG in French) is a unique observatory of malaria chemoresistance in the Guyanese shield which works with research laboratories of the Institut Pasteur, Paris. This network strategy offers a very attractive perspective for applications of modern tools, including the validation of chemoresistance molecular markers, for malaria control at both medical and public health levels. Some examples related to chloroquine and artemether resistance are given.

Circulating fibrosis markers, eosinophil cationic protein and eosinophil protein X in patients with Wuchereria bancrofti infection: association with clinical status.

We measured the concentrations of several circulating fibrosis markers (type I collagen I, type III procollagen, hyaluronan) and eosinophil granule proteins (ECP and EPX) in lymphatic filariosis patients to investigate their relationship with clinical, parasitological and immunological data. This study was conducted in Polynesian patients with various stages of the disease (acute lymphangitis, chyluria, hydrocoele, elephantiasis), a closely related microbial lymphangitis and endemic controls. We observed modifications of the different markers in this pathology. Serum type I collagen and PIIINP were decreased. Serum hyaluronan, linked to perilymphatic granulomatous inflammation, was significantly increased in acute lymphangitis and elephantiasis patients. Serum ECP was also increased, at the limit of significance in our sample, in elephantiasis patients. These two last markers, already validated in another helminth disease, schistosomiasis, have potential interest in terms of follow-up of morbidity in these parasitic diseases.

[The history of lymphatic filarlasis control programme in French Polynesia: lessons from a 50 years effort]. / Histoire de la lutte contre la filariose lymphatique en Polynésie française: leçons de 50 années d'efforts.

With a mean prevalence of microfilariaemia superior to 15% in the four archipelagos of the territory French Polynesia was confronted with a huge public health problem of Wuchereria bancrofti - associated filarias during the 50s. Supported by a strong US sponsoring, a large scale control campaign based on diethylcarbamazine (DEC) distribution was launched and led to the method of spaced doses (the most useful protocol being one annual DEC dose). Progressively applied to the whole Polynesian population since 1974, this very innovative programme had generated the idea of a possible eradication of the parasitosis. Meanwhile at laboratory level important progress in Immunology (mainly the validation of rapid diagnosis tests detecting a specific antigenemia) and later in Molecular Biology (with the main application being the follow-up of the infection status of the vector Aedes polynesiensis) questioned this optimistic concept (one lesson given by the study of Maupiti island, considered as a 0% reference island for a long time). More recently a regional WHO-sponsorized control programme, called PacELF, has for main objective the elimination of lymphatic filariasis as a public health problem in the South Pacific region near 2010. This objective argues for using a (DEC and albendazole) drug combination cumulating micro- and macro-filaricid activities. The dream of a lymphatic filariasis free Pacific is coming back again.

Forty years of chromoblastomycosis in Madagascar: a review.

Confirmed cases of chromoblastomycosis in Madagascar from 1955 through 1994 were studied retrospectively. The total number of cases reported was 1,343, of which 98.5% were confirmed by histopathology. Only 30.8% of the cases showed a positive cultivation on mycologic media, and Fonsecaea pedrosoi was identified from 61.8% of the fungal strains. Two distinct areas of endemic chromoblastomycosis, each with a characteristic ecosystem and a single species, are identified. Madagascar represents the most important focus of this fungal disease described to date in the world.

Relationships between several markers of extracellular matrix turn-over and ultrasonography in human Schistosomiasis mansoni.

We measured the concentrations of several serum and urinary fibrosis markers, which are metabolites of extracellular matrix, in schistosomiasis patients to investigate their relationship with the ultrasonographic scoring system and with parasitologic data. This study was conducted in patients with various stages of the disease evaluated by ultrasonography (intestinal disease with no organ involvement, with minor hepatosplenic involvement and with severe disease) and in endemic controls. The level of hyaluronan, which were increased in infected patients compared with controls (P < 0.01), was the only fibrosis marker that correlated with the ultrasonographic score (P = 0.003) and is thus a potential serum marker of schistosomiasis-associated morbidity. Urinary free pyridinoline levels were lower (P < 0.001) in infected patients with fibrosis (score > or = 1) than in nonfibrotic patients. A two-year follow-up of the patients treated with praziquantel showed that type I collagen and hyaluronan decreased during the first year post-treatment, whereas free pyridinolines peaked after 12 months and decreased thereafter.

Ultrasonographical assessment of morbidity in schistosomiasis mansoni in Madagascar: a community-based study in a rural population.

Between June and November 1993, a parasitological, clinical and ultrasonographical survey was carried out in the mid west of Madagascar, among the whole population of a village where Schistosoma mansoni was endemic. S. mansoni eggs were found in the stools of 61.8% of the 544 individuals examined; the highest prevalence of infection (85.7%) was observed in the 15-19 years old age group. The most intense infections were recorded in the 10-14 years age group, in which the geometric mean egg count was 265 eggs/g of faeces and 34.3% of the individuals excreted more than 400 eggs/g. The egg count decreased steadily from the age of 15 years. Ultrasonographical examination was performed in 482 inhabitants older than 2 years: 29% of them presented definite schistosome associated liver alterations according to the proposals for staging S. mansoni infection made by the World Health Organization Cairo working group. Stage 3 was never observed in subjects under 30 years old. This is consistent with the need for a long-standing infection before serious lesions occur. A significant relationship between egg count and degree of liver alterations was found only in the 20-29 years age group.

Killer cells in human cutaneous leishmaniasis.

In French Guiana, American cutaneous leishmaniasis is localized in the skin. The host response appears to be effective since few extra- or intracellular organisms can be found in tissue lesions, and we never observed any cutaneous dissemination or visceral involvement. However, this response is not fully effective since lesions may last for months. By using immunoperoxidase techniques and monoclonal antibodies directed against various cell populations, we examined the local immune response in skin biopsies. We found a high percentage of cells with the K/NK phenotype, a variable but usually high percentage of cells with the T cell phenotype bearing TAC receptors, and moderate numbers of monocytes and B cells. These results suggest that K/NK cells could play a role in the local control of parasite dissemination.

Morbidity of schistosomiasis mansoni in the highlands of Madagascar and comparison of current sonographical classification systems.

To study the morbidity of schistosomiasis mansoni in the highlands of Madagascar, a cross-sectional study examined the extent to which liver fibrosis occurred in a rural community. The Managil and the Cairo classification systems were used. A second purpose was to investigate the effect of the measurements of 2 different branches of the portal vein (either segmental or sub-segmental branches) on the resulting staging of morbidity using the Cairo classification system. In a rice farmer village, 656 inhabitants (95% of the total population) were parasitologically examined; 561 patients underwent sonographic work-up based on the Managil scoring system, and in 307 randomized patients the outer to outer diameters of both the segmental and the sub-segmental branches of the portal vein were measured and scored by the Cairo classification system. Overall prevalence of schistosomiasis mansoni in the study area in 1994 was 68.3%. Upon sonographic examination and scoring by the Managil system 23.4% of the population showed liver changes (Managil degree I/II/III, 20%/2.5%/0.9%). Measuring the sub-segmental branches only and scoring by the Cairo classification, 19% of the study population were found to have liver changes, none with severe fibrosis. By contrast, 82% were found to have liver changes (Cairo degree 1/2/3, 70%/11%/2%) when the segmental branches were measured. The diameters of the sub-segmental branches were about two-thirds of those of the segmental branches. Both the Cairo- and the Managil-examination protocols have pitfalls. Using the Cairo classification, a considerable systematic error in classifying morbidity is created by measuring different branches of the portal vein.

Schistosoma haematobium infection in western Madagascar: morbidity determined by ultrasonography.

To assess the morbidity related to Schistosoma haematobium infection in western Madagascar, an ultrasonographic examination was performed of 574 inhabitants > 5 years old in a village in an old-established endemic area where no prior systematic antischistosomal treatment had been given. The overall prevalence of infection was 75.9% and the geometric mean egg count of positive individuals was 36 eggs/10 mL of urine. Recent haematuria had been experienced by 31.8% of individuals. Echographic abnormalities of the urinary tract were present in 50.5% of individuals: they were more frequent in males. Bladder wall lesions were observed in 93.1% of individuals with ultrasonographic changes, irregularities of the inner surface being the most common finding. Congestive changes were noted in 8.4% of kidneys, but we observed only 4 severe congestions. Bladder lesions and congestive changes in kidneys predominated in youth; their presence and severity were significantly correlated with egg excretion. In 12 inhabitants, grade 1 periportal fibrosis was observed, but no significant association was found with S. haematobium infection. In a control village, where the prevalence of S. haematobium infection was 7%, moderate congestion of kidneys was observed in 2% of examined inhabitants, and bladder changes in 6%, with a significant relationship with S. haematobium infection.

Reversibility of Schistosoma mansoni-associated morbidity after yearly mass praziquantel therapy: ultrasonographic assessment.

A parasitological, clinical and ultrasonographic longitudinal study was undertaken in 1993 in a focus hyperendemic for Schistosoma mansoni infection in the central highlands of Madagascar. All the inhabitants were systematically treated with praziquantel. A complete examination and treatment were repeated each year. Among the 289 villagers who underwent the complete 3 years' follow up, 65.9% excreted eggs at the initial survey and the mean egg count of infected individuals was 202 eggs/g. In 1996, the prevalence of infection was 19.3% with a mean egg count of 27 eggs/g and, among inhabitants aged > 44 years, only one was found to be infected. The proportion of individuals complaining of bloody stool decreased from 24.9% in 1993 to 8.4% in 1996. Compared to the initial clinical examination, the age-adjusted prevalence of splenomegaly was significantly lower in 1996, but remained high: 62% in the 10-14 years age group and 59% in individuals aged > 24 years. Ultrasonographic examination after 3 years of praziquantel therapy showed a marked decrease of the overall prevalence of schistosomal hepatic fibrosis, from 28% in 1993 to 10.3% in 1996. This improvement had already been achieved during the second year of follow-up for most subjects. Usually, the reversal of morbidity affected individuals classified as stage 1 at the beginning of the study. Stage 3 was not observed in the last 2 surveys. One patient's ascites disappeared during the follow-up, associated with a significant reversal of periportal fibrosis. Our results indicate that repeated praziquantel therapy can lead to improvement of liver morbidity and the prevention of the development of schistosomal hepatic fibrosis, even in an old-established hyperendemic focus.

Schistosoma haematobium induced lesions in the female genital tract in a village in Madagascar.

Female genital schistosomiasis, FGS, was investigated in a gynaecological study as part of an overall community based morbidity survey, including parasitological and ultrasonographical examination, of a Schistosoma haematobium endemic area in Madagascar. Women (103), of childbearing age (15-49 years), were included for a gynaecological examination and visible lesions of vagina and cervix were biopsied in order to determine the origin of the lesion. Furthermore all women were screened for the presence of schistosome ova using PAP smears from the vagina and the endo/exo cervix. In total 15 women showed schistosome ova in the vagina and/or cervix (median age 24 years and range 15-36 years). Of 36 women with cervical abnormalities, 12 eggs were detected by cervical biopsy (33%). In addition, two of the 12 presented vaginal induration, which contained eggs. Six women had eggs in their PAP smears of which three were egg negative by cervical biopsy. The prevalence of positive S. haematobium egg excretion in the urine among the 103 women was 69% and the geometric mean egg count of positive individuals was 51 eggs/10 ml of urine. Five of the 15 women with confirmed FGS had < or = 1 egg/10 ml of urine. Bladder lesions and congestive changes in the kidneys were demonstrated by ultrasonographic examination in 33 and 9% of the 103 women, respectively. None of the 15 women with confirmed FGS had renal congestion. Our study demonstrates that FGS is a common manifestation of the infection with S. haematobium, even in lightly infected individuals.

Anti-neutrophil cytoplasmic antibodies in patients with chromomycosis.

OBJECTIVE: Antineutrophil cytoplasmic antibodies (ANCA) are a family of antibodies that react to proteins within neutrophil granules and monocyte lysosomes, and occur prominently in sera from patients with systemic necrotizing vasculitis. The cytoplasmic staining pattern (c-ANCA) is very sensitive and specific for Wegener's granulomatosis (WG), and most commonly results from reactivity with proteinase 3 (PR3). The features of tissue damage in the fungal infection chromomycosis, in particular polymorphonuclear neutrophil (PMN) infiltration and granuloma formation, bear a resemblance to that seen in WG. METHODS: We tested sera from 25 patients with clinical and histologic diagnosis of chromomycosis for the presence of ANCA by indirect immunofluorescence. These same sera were analyzed for reactivity to neutrophil primary granule extracts and PR3 by ELISA. RESULTS: Five of the 25 patients (20%) had detectable c-ANCA, without central accentuation, at serum dilutions of at least 1:40. Three of these 5 ANCA-positive patients reacted with neutrophil primary granule extracts by ELISA; however, none of them reacted with PR3. CONCLUSIONS: These results demonstrate that fungal infection should be included among the conditions, unrelated to necrotizing vasculitis, that can trigger autoreactivity against myeloid lysosomal antigens.

Interferon-gamma, an anti-fibrogenic cytokine which binds to heparan sulfate.

Interferon-gamma is a T cell secreted cytokine. It has a great number of biological activities, among which is the down regulation of collagen molecules. IFN-gamma acts through cell surface receptors, but also binds to heparan sulfate proteoglycans. In vivo, it is postulated that the heparan sulfate/IFN-gamma interaction can modulate the activity and availability of the cytokine.

Immunohistochemical study of type I collagen turn-over and of matrix metalloproteinases in chromoblastomycosis before and after treatment by terbinafine.

The distribution of type I collagen, the major component of human dermis, was characterized by immunohistochemistry in skin lesions of chromoblastomycosis, a chronic cutaneous mycosis, before and after a specific antifungal treatment with terbinafine to study the changes induced in the lesions by the treatment. Newly synthesized type I collagen was studied with an antibody directed against the aminoterminal propeptide of the molecule (PINP), whereas mature, cross-linked type I collagen was detected with an antibody against the carboxyterminal telopeptide of type I collagen (ICTP). The isopeptide N epsilon gamma-glutamyl lysine (N epsilon gamma GL), synthesized by transglutaminase and able to cross-link several components of the extracellular matrix, has also been investigated with two monoclonal antibodies to determine if it is involved in the stabilisation of the fibrotic cutaneous lesions. The degradative process involved in the remodelling has also been assessed by immunohistochemistry with anti-metalloproteinase (MMP-1 and MMP-9) and anti-tissue inhibitor (TIMP-1) antibodies. All tissue macrophages stained for CD68 and MMP-9, but not for MMP-1, while the polymorphonuclear neutrophils had an elastase and a weak MMP-9 phenotype. The fibroblasts of fibrotic areas stained constantly for N epsilon gamma GL and PINP. The immunostaining of extracellular matrix for ICTP and N epsilon gamma GL, and the number of PINP-positive fibroblasts, decreased significantly after one year of antifungal treatment. Terbinafine treatment decreases the synthesis of type I collagen and leads to a partial reversal of the cutaneous fibrotic lesions, independently of the cure of the fungal infection.

Cell-matrix patterns in the cutaneous lesion of chromomycosis.

Chromomycosis is a chronic fungal infection characterized by dermal fibrosis with persisting fungi in situ, generally leading to a verrucous skin lesion. The absence of good clinical results under specific treatment suggests irreversibility of the fibrotic lesion. Frozen and paraffin-embedded skin biopsies of eleven patients with chromomycosis due to Phialophora pedrosoi were studied by immunohistochemistry and electron microscopy. Distinct cell-matrix patterns were found in different tissue localizations: neutrophilic abscesses with oedema and necrotic keratinocytes in the epidermis; dense connective matrix around inflammatory infiltrates, mainly composed of macrophages and giant cells, and organized granuloma in the dermis. Active fibroblasts and mast cells were constantly observed. The inability of fibrotic tissue to be remodelled seems correlated to the nature and the organization of the matrix components but, the factors triggering the initial fibrogenic events remain to be characterized.

Matrix remodelling and fibroblast phenotype in early lesions of human cutaneous leishmaniasis.

The connective matrix participates directly in early pathological events observed in the cutaneous lesion of leishmaniasis, due to Leishmania braziliensis guyanensis. A sample of 19 skin biopsies was examined by light and electron microscopy, in order to identify the matrix components (collagen isotypes I to IV, elastin and membrane associated proteins) of the dermal infiltrate, and the pattern of organization of the reparative connective matrix. An extensive remodelling process of apparently parasite-independent nature involves different fibroblast sub-populations. The original organization of this immune-mediated lesion offers a rare opportunity to study in situ the local inflammatory mediators inducing the activation of fibroblasts and macrophages.

Macrophage function in patients with American cutaneous leishmaniasis: in vitro cytotoxicity and interleukin-1 production.

Monocyte-derived blood macrophages of untreated patients with Leishmania braziliensis or Leishmania mexicana amazonensis infections show anomalies in their nonspecific immune functions. Their ability to kill HeLa cells or to produce interleukin-1 in vitro in response to lipopolysaccharide plus Candida albicans is lower than controls indicating that acquired or innate macrophage deficiencies may be involved in the course of the disease.

Assessment of immunochromatographic test for rapid lymphatic filariasis diagnosis.

Two rapid immunodiagnostic tests (ICT Filariasis test), developed for the quick diagnosis of Wuchereria bancrofti infection, have been validated in laboratory and field situation. The aim of this study was to assess the performance and usefulness of this antigen capture assay as a diagnostic method in three foci of lymphatic filariasis, located in the South Pacific (Society archipelago, French Polynesia), with different levels of endemicity. A sample of 1,595 patients was tested with this assay in parallel with a reference Og4C3 antigen capture assay and microfilariae detection. A second-generation ICT test, available for whole blood analysis, was also tested in parallel with the first generation test, developed for serum analysis, on a sample of 50 reference cases. The correspondence between the results obtained with the two rapid tests was excellent, without any influence of rheumatoid factors, but the sensitivity was in both cases slightly inferior to the one obtained with the ELISA reference test. This seems particularly true in epidemiological situation where a high proportion of amicrofilaraemic, adult worm carriers are observed.

Role of streptococcal infection in the acute pathology of lymphatic filariasis.

Growing evidence suggest that secondary bacterial, mainly streptococcal, infections contribute significantly to recurrent episodes of acute adenolymphangitis (ADL) of filarial origin. We examined the role of group A streptococci in the progression of lymphedema in Polynesian patients with filariasis-related ADL (22 cases) or chronic pathology (10 cases), or with erysipela (10 patients) and, as controls, in 20 healthy adults. Antistreptolysin O (ASLO) and anti-streptodornase B (ASDB) titers were systematically determined in parallel to parasitological and biochemical tests. ASLO and ASDB assays were positive in 100% of erysipela, 75% of filarial ADL as compared to 50% of chronic pathology and 39% of healthy controls. Interestingly, by opposition to ASLO titers which were not significantly different between the four groups, ASDB titers were higher in ADL (p = 0.019) and erysipela (p = 0.002) than in controls. These results support the hypothesis that recurrent streptococcal infections may have an important role in the pathogenesis of ADL in lymphatic filariasis.

Immunohistochemical analysis of the mucosal lesion in mucocutaneous leishmaniasis.

Using antibodies against surface antigens of inflammatory cells and against extra-cellular matrix components, immunocytochemical studies permit the investigation of the in situ cellular immune response and the associated fibrosis, in mucosal lesions. 57 paraffin embedded skin biopsies of mucocutaneous leishmaniasis originating from Bolivia, and due to Leishmania (Viannia) braziliensis, were studied. Memory T cells predominate within a non-organized granulomatous reaction, in which were observed proliferating macrophages. At the top of the lesion, epithelial cells expressed HLA-DR. Some characteristics of this lesion, particularly its chronic destructive pattern, presently lack any clear explanation.