Fungal interdigital tinea pedis in Dakar (Senegal).

Fungal interdigital tinea pedis (FITP) is the most frequent dermatomycosis in industrial countries. In African tropics, it's a rare motive of consultation and is discovered while complicated. The aims of this article were: to determine the frequency of interdigital tinea pedis among overall mycological analysis in our laboratory; to study epidemiological, clinical and mycological aspects of FITP in outpatients attending the Le Dantec mycology laboratory in Dakar. A total of 62 males (60%) and 42 females (40%), mean age: 43.15 years (range: 11-81 years), were received from January 2011 to December 2015 for suspicion of FITP. Skin specimens were taken from all patients for microscopy and fungal culture. The frequency of ITP represents 5.6% (104/1851) among our overall mycological analysis. FITP was confirmed in 68 patients (SPI=65.38%), mainly located between the 4th and 5th toes and 71 fungal species were isolated (CPI=68.27%). Among patients with confirmed FITP, there were 38 males (56%) and 30 females (44%). The prevalence was highest in patients between 44 and 54 years (26%). Candida albicans, Fusarium solani and Trichophyton interdigitale were shown to be the most common pathogens respectively for yeasts (39%), non-dermatophytic filamentous fungi (NDFF; 21%) and dermatophytes (11%). So FITP isn't a common reason for consultation in Dakar but its simple parasitic index (SPI) is still very high and dermatophytes formerly the main causative agents are being relegated to third place behind yeasts and NDFF.

[Keratomycosis due to Fusarium oxysporum treated with the combination povidone iodine eye drops and oral fluconazole]. / Kératomycose à Fusarium oxysporum traitée par l'association de la povidone iodée en collyre et du fluconazole per os.

In developing countries where systemic antifungal are often unavailable, treatment of filamentous fungi infection as Fusarium is sometimes very difficult to treat. We report the case of a keratomycosis due to Fusarium oxysporum treated by povidone iodine eye drops and oral fluconazole. The diagnosis of abscess in the cornea was retained after ophthalmological examination for a 28-year-old man with no previous ophthalmological disease, addressed to the Ophthalmological clinic at the University Hospital Le Dantec in Dakar for a left painful red eye with decreased visual acuity lasting for 15 days. The patient did not receive any foreign body into the eye. Samples by corneal scraping were made for microbiological analysis and the patient was hospitalized and treated with a reinforced eye drops based treatment (ceftriaxone+gentamicin). The mycological diagnosis revealed the presence of a mold: F. oxysporum, which motivated the replacement of the initial treatment by eye drops containing iodized povidone solution at 1% because of the amphotericin B unavailability. Due to the threat of visual loss, oral fluconazole was added to the local treatment with eye drops povidone iodine. The outcome was favorable with a healing abscess and visual acuity amounted to 1/200th. Furthermore, we noted sequels such as pannus and pillowcase. The vulgarization of efficient topical antifungal in developing countries would be necessary to optimize fungal infection treatment.

[Nondermatophytic and noncandidal fungi isolated in Le Dantec University hospital of Dakar in 2014: Epidemiological, clinical and mycological study]. / Champignons non dermatophytiques et non candidosiques isolés au CHU Le Dantec de Dakar en 2014 : étude épidémiologique, clinique et mycologique.

In recent years, the incidence of superficial fungal infections involving nondermatophytic and noncandidal fungi increased considerably. The objective of this work was to analyze the epidemiological, clinical and mycological fungal infections due to nondermatophytic and noncandidal fungi diagnosed in the laboratory of parasitology-mycology of Le Dantec hospital in Dakar. With a retrospective study of the various cases of nondermatophytic and noncandidal fungi isolated in the laboratory of parasitology-mycology during the period of November 2013 to December 2014, we collected 22 cases of infections in 11 men and 11 women; age ranging from 17 to 75 years with a mean of 45.3 years (sex ratio=1): eight cases of intertrigo, seven cases of onychomycosis, four cases of palmoplantar keratoderma (KPP), a case of onychomycosis associated with interdigital intertrigo, a case of infectious myositis and one case of African histoplasmosis. We have isolated and identified a total of 22 nondermatophytic and noncandidal fungi: ten Fusarium, five Trichosporon, two Chrysosporium, two Geotrichum, one Rhodotorula, one Neoscytalidium dimidiatum and one Histoplasma capsulatum var. duboisii. So we are seeing the emergence of nondermatophytic and noncandidal increasingly isolated from superficial and local lesions. These fungi, generally contaminants or commensal, cause a problem regarding their direct involvement in pathological processes in which they are isolated. So we should respect the recommendations proposed for their involvement in pathological processes and, by a collaboration between clinician and biologist, demonstrate their real involvement through effective, targeted treatment.

[Epidemiological profile of Tinea capitis in Dakar (Senegal). A 6-year retrospective study (2008-2013)]. / Profil épidémiologique des teignes du cuir chevelu à Dakar (Sénégal). Bilan d'une étude rétrospective de six ans (2008-2013).

INTRODUCTION: Tinea capitis is considered as a public health problem in Senegal. The aim of this study was to investigate trends in the incidence, the mycological and epidemiological aspects of tinea capitis diagnosed at Le Dantec Hospital in Dakar. METHOD: Our work is a retrospective study concerning all scalp samples taken by the parasitology laboratory, over a 6-year period (2008-2013). RESULTS: A total of 1640 specimens were examined. Of these, 566 were positive with direct examination and after culture. We noted the reduction of patients and of the incidence of tineas during 6 years with variations of 147 (46.82%) to 37 (22.02%). The average incidence of the tineas during six years was 34.51%. Patients' age varied between 1 to 83 years with a mean of 27.33 years. Prevalence varied between age groups, with 10.61 % in adults between 20 to 29 years, 7.19% in children between 0 to 9 years, 6.04% between 10 to 19 years, and 5.91% in adults between 30 to 39 years. Women were more infected 469 (82.9%) than men 97 (17.1%). The main dermatophytes isolated were: T. soudanense in 318 cases (56.18%), T. rubrum in 104 cases (18.37%), M. langeronii in 72 cases (12.72%), M. canis in 36 cases (6.36%), and T. mentagrophytes in 26 cases (4.60%). CONCLUSION: Our study showed a decrease in the annual incidence of tinea capitis over the study period with an evident increase in trichophytic tinea. This study showed that tinea is endemic in Senegal mainly among women between 20 and 29 years.

[Tinea pedis due to Fusarium solani in Dakar]. / Intertrigo interorteils à Fusarium solani à Dakar.

A patient presented with intertrigo at the second, third and fourth interdigitals spaces lasting for four years in which Fusarium solani was highlighted. The search for contributing factors revealed a concept of foot washing with water at least five times a day for ablutions, associated with wearing closed shoes all day and the absence of immunosuppression and diabetes. The diagnosis of Fusarium was made on the basis of direct examination and culture. Combined treatment with griseofulvin oral and topical ciclopirox was introduced and allowed healing after 45 days at which an antifungal powder was prescribed for relay. This case adds to the rare cases of intertrigo Fusarium sp. and confirms the frequent practice of ablutions as favoring factor.

[Qualitative fungal composition of services at risk of nosocomial infections at Aristide Le Dantec Hospital (Dakar)]. / Composition qualitative de la flore fongique de l'environnement de 07 services à risque d'infections fongiques au CHU Aristide Le Dantec (Dakar).

INTRODUCTION: In hospitals, the quality control of the air is a key element. Indeed airborne fungi constitute a real danger for patients hospitalized in wards at risk of nosocomial infections especially when they are immunocompromised. OBJECTIVES: The objective was to determine the qualitative fungal flora composition of wards at risk of nosocomial infections at Le Dantec teaching hospital. MATERIALS AND METHODS: Between April and May 2013, 73 samples were collected from 45 compartments within seven services at risk of nosocomial infection at Aristide Le Dantec teaching Hospital (Dakar). Samples were made once by sedimentation method and the percentage of positive cultures was 100%. The most represented species were Cladosporium spp. (91.1%), Aspergillus spp. (86.6%), Penicillium spp. 71.1% and Candida spp. (57.7%). Candida albicans and Aspergillus fumigatus were isolated respectively at 15.5% and 11.1%. Wards have been classified according to the number of species isolated; 11 species in pediatric oncology, 10 species in pediatric surgery/neonatal and intensive care, nine species for oncology, eight species in general surgery and dermatology, and four species in internal medicine. CONCLUSION: This study shows that fungi causing nosocomial infections are present in hospital and their monitoring should be included in the program of Nosocomial Infections Prevention Committees (CLIN).

[Mycological profile of onychomycosis in Dakar (Senegal)]. / Profil mycologique des onychomycoses à Dakar (Sénégal).

OBJECTIVE: Onychomycosis are a mycose of nail due to fungi. According to published data, they stands for half of all nail abnormalities. This survey was carried out to determine the frequency and the fungi involved in onychomycosis in Dakar. MATERIAL AND METHODS: This study was carried out at the laboratory of parasitology and mycology at Le Dantec Hospital, in Senegal from January 2008 to December 2012 and includes 507 patients. RESULTS: Onychomycosis were mycologically proved in 58.78% (298/507) of patients. Patient's age varies between 02 years to 82 years with a mean of 34.24 years. Women were more infected than men (sex-ratio was 2.38). Onychomycosis due to dermatophyte represented 37.92% (113/298) of patients and were essentially located on toes (60.71%). Distal and lateral subungual onychomycosis was the most frequent clinical form. Trichophyton rubrum and Trichophyton interdigitale were isolated respectively in 53.6% and 26.1% on toes. Yeasts represented 59.06% (176/298) of onychomycosis and were essentially located on fingernails (80.11%). Candida albicans represented 90.86% of isolated yeasts. Molds were isolated in nine cases (3.02%) and predominated in toenails. CONCLUSION: Among 507 patients with onychopathy, this study identified 298 cases of onychomycosis. T. rubrum was the main dermatophytes and was isolated on toenails whereas on fingernails C. albicans was more often observed.

[Cryptosporidiosis in Senegalese children: prevalence study and use of ELISA serologic diagnosis]. / La cryptosporidiose de l'enfant au Sénégal : étude de la prévalence et apport du diagnostic sérologique par ELISA.

This is a prospective, descriptive and analytic study conducted from July 2011 to September 2011 at the Children National Hospital Albert Royer of Dakar and at the Vélingara Health District. It was focused on children under 15 without reference to HIV status. For each child, a sample of stool was examined by the Ziehl-Neelsen modified staining and by ELISA using the "Cryptosporidium Antigen Detection Microwell ELISA kit" designed to detect Cryptosporidium spp antigens. The aim of our study was to determine the prevalence of cryptosporidiosis in rural and hospital areas and to measure the performance of the ELISA kit that we used. Out of the 375 stool examinations performed with the Ziehl-Neelsen modified staining, 17 had revealed the presence of Cryptosporidium spp (4.53%). The prevalence in rural areas was 2% while the hospital prevalence was 7.4%, of which 1.8% (1/57) were from urban areas and 9.8% (12/122) from suburban areas. No positive case was observed in children over 10 years. By ELISA, 23 positives cases were reported corresponding to a prevalence of 6.13% (1.8% in children living in urban areas, 13.1% in children from suburban areas and 3%living in rural areas).The correlation of this assay with the Ziehl-Neelsen modified staining, considered as the reference method, found that this assay had a sensitivity of 58.82% and a high specificity reaching 96.37%. The positive predictive value (PPV) was 43.4% while the negative predictive value was 98%. Cryptosporidiosis is a significant cause of parasitic infection among children in Senegal. Antigen detection of Cryptosporidium spp by ELISA in stool can be a complementary tool in the diagnosis of cryptosporidiosis.

[Dermatophytosis diagnosed at the laboratory of parasitology and mycology of Le Dantec Hospital in Dakar between 2007 and 2011]. / Dermatophyties diagnostiquées au laboratoire de parasitologie et mycologie de l'hôpital Le Dantec de Dakar, entre 2007 et 2011.

INTRODUCTION: Dermatophytosis is a disease caused by dermatophytes, filamentous fungi adapted to human and animal keratin, colonizing and infecting human skin. The goal of this study was to identify dermatophytes responsible for dermatophytosis among patients, seeking for care in Dakar. Material and methods This study was carried out at the laboratory of parasitology and mycology at Le Dantec Hospital, in Senegal between June 2007 and December 2011, and included 2026 patients. RESULTS: Among these 2026 patients, 796 patients presented a dermatophytosis, confirmed after direct examination and/or culture in 1044 specimens. Patients' age varied between 3months to 89years with 25.5 years of age average; the infestation index was 39.3%. Patients between 20-29years were more infested with 15.3%, followed by 10-19years (9.1%), 0-9years (8.7%), 30-39years (2.7%), 40-49years (1.5%), 50-59years (1.3%), 60-69years (0.4%), 70-79years (0.2%), and 80-89years (0.1%). Women were more infected (77%) than men 23%. The main species isolated were Trichophyton soudanense (52.78%), Trichophyton rubrum (30.94%), Microsporum canis (4.89%), Trichophyton mentagrophytes var. interdigitale (4.50%), Microsporum langeronii (3.54%), Trichophyton mentagrophytes var. mentagrophytes (1.82%). CONCLUSION: This study shows that dermatophytes and dermatophytosis are endemic to Senegal.

[Intestinal helminthiasis diagnosed in Dakar, Senegal]. / Prévalence des helminthoses digestives diagnostiquées à l'hôpital Le Dantec de Dakar, Sénégal.

The goal of this study was to determine the prevalence of digestive helminthiasis among patients referred to the laboratory of Parasitology and mycology at Le Dantec Hospital in Dakar for examination of stool samples from 2004 to 2009. Of 1 526 direct stool examinations (Ritchie and Baerman techniques) analyzed at the laboratory of Parasitology and Mycology of Le Dantec Hospital from 2004 to 2009, 310 were positive for intestinal helminthiasis, for a prevalence of 20.3%. The main species found were: Ascaris lumbricoides, Trichuris trichiura, Strongyloides stercoralis, Tænia saginata and Tænia solium. Most patients had a single parasite (90.1%, versus 9% with two and 0.9% with three). Men are infected more often than women, accounting respectively for 58% and 42% of the infections, for a sex ratio of 1.38. Children aged 10 to 15 years had the highest prevalence of infection: 34.5%. The results show that digestive helminthiasis is endemic in Dakar, where it is necessary to implement campaigns of deworming, health education and environmental improvement.

[Update on toxoplasmosis prevalence based on serological tests in pregnant women in Dakar, Senegal from 2002 to 2006]. / Evolution de la séroprévalence de la toxoplasmose chez la femme enceinte a Dakar, Sènegal de 2002 a 2006.

The purpose of this study was to update data on toxoplasmosis antibody prevalence based on antenatal surveillance tests in pregnant women in Dakar, Senegal. The study population consisted of 941 pregnant women referred for diagnosis of toxoplasmosis in the Laboratory of Parasitology and Mycology at Le Dantec University Hospital Center from 2002 to 2006. Two tests using the solid-phase immunoenzymatic method were performed on venous blood samples collected at 3 weeks of interval (S1 and S2). This double testing technique was designed to detect increases in IgM and IgG antibody levels in order to confirm diagnosis of toxoplasmosis by ruling out immune response, acquired immunity or nonspecific antibody fixation. Comparison of S1 and S2 results in the 941 patients indicated a prevalence of 7.7% and 0% respectively for IgM+IgG- cases, 23.3% and 24.3% respectively for IgM+IgG-cases, and 11.3% and 10.2% respectively for IgM+IgG+ cases. The overall prevalence of toxoplasmosis antibodies was 34.5%. These data showing a high prevalence of toxoplasmosis among pregnant women in Dakar underscore the need to improve serological screening and follow up.

[Disseminated histoplasmosis due to Histoplasma capsulatum var. duboisii in Senegal. A case in HIV-infected patient]. / Histoplasmose disséminée àHistoplasma capsulatum var. duboisii au Sénégal. À propos d'un cas chez un patient VIH positif.

INTRODUCTION: Histoplasmosis, a disease due to Histoplasma capsulatum, is an invasive opportunistic fungal infection, endemic in Africa. So, the occurrence of african histoplasmosis associated with HIV infection has been rarely reported despite the high prevalence of both pathogens in this area. We report the first case of disseminated african histoplasmosis in an HIV-infected Senegalese patient. OBSERVATION: A patient, 50-year-old has been admitted for umbilicate, necrotic and disseminated papulonodular lesions with oral infection, fever and reduction of total body mass. HIV1 test was positive, and CD4 count was 4/mm(3). Direct examination of ulcerated lesions shown extracellular, large, doubly contoured yeasts. After culture, we obtain brownish colonies, septate hyphae, echinulated chlamydospores characteristic of Histoplasma. Cutaneous biopsy revealed polymorphous granulomatous infiltrate, giant cells containing numerous large, doubly contoured, thick-wall yeast-bodies characteristic of H. capsulatum var. duboisii. DISCUSSION: The association AIDS and histoplasmosis frequency is probably underestimated because the difficult diagnosis and the ignorance of the medical staff.

[Mycetomas diagnosed in Senegal from 2008 to 2010]. / Mycétomes diagnostiqués au Sénégal de 2008 à 2010.

INTRODUCTION: Mycetomas are inflammatory pseudotumours of subcutaneous and possibly osseous soft fabrics, generally polyfistulas with chronic mode of evolution. PATIENTS AND METHODS: This study was carried out at the laboratory of parasitology and mycology of Le Dantec hospital in Dakar, Senegal, including 113 patients, from june 2008 to july 2010. RESULTS: Patients were from different regions in Senegal and in neighborhood countries, referred to the laboratory for mycetoma diagnosis. Among the 250 patients referred, 113 were positives after direct observation and culture corresponding to 45.2% index of infestation. The age range varies between 13 to 73years with an average age of 33.9years. The age bracket ranging between 20-39years is more infected (27.34%), followed by 40-59years (25.2%), 60years and more (4.5%), 30-39years (16.64%), 13-19years (7.2%). The infection sex rate were, male: 79.6% and female: 20.4%. Infection prevalence profession dependant was found mainly in farmers and breeders with respectively: 48.7%, and 42.5%. The foot infestation is most represented with 72.5%, then leg (12.3%), knee (7.1%), scalp (2.7%), hand (1.8%). The other localizations are found with less than 1%: back, thigh, chest and ganglion inguinal. According to mycetoma agents, fungy are represented than mycetomas actinomycosic with respectively 70% and 30%. The species found were: Madurella mycetomatis (53.1%), Actinomadura pelletieri (23%), Leptosphaeria senegalensis (9.7%), Streptomyces somaliensis (2.6%), Actinomadura madurae (2,6%), Pseudallescheria boydii (1.8%), Nocardia spp. (1.8%), Scedosporium apiospermum (0.9%), Fusarium solani (0.9%). We found agents of dermatophytes: Microsporum langeronii (1.8%), and Trichophyton mentagrophytes (0.9%). CONCLUSION: This study confirms that mycetomas are endemic affections in Senegal, where it still remain a real cause of disability among population leaving in rural area.

Erythrocyte invasion profiles are associated with a common invasion ligand polymorphism in Senegalese isolates of Plasmodium falciparum.

Plasmodium falciparum parasites use multiple ligand-receptor interactions to invade human erythrocytes. Variant expression levels of members of the PfRh and PfEBA ligand families are associated with the use of different erythrocyte receptors, defining invasion pathways. Here we analyse a major polymorphism, a large sequence deletion in the PfRh2b ligand, and erythrocyte invasion profiles in uncultured Senegalese isolates. Parasites vary considerably in their use of sialic acid-containing and protease-sensitive erythrocyte receptors for invasion. The erythrocyte selectivity index was not related to invasion pathway usage, while parasite multiplication rate was associated with enhanced use of a trypsin-resistant invasion pathway. PfRh2b protein was expressed in all parasite isolates, although the PfRh2b deletion was present in a subset (approximately 68%). Parasites with the PfRh2b deletion were found to preferentially utilize protease-resistant pathways for erythrocyte invasion. Sialic acid-independent invasion is reduced in parasites with the PfRh2b deletion, but only in isolates derived from blood group O patients. Our results suggest a significant role for PfRh2b sequence polymorphism in discriminating between alternative erythrocyte receptors for invasion and as a possible determinant of virulence.

Etude de la prevalence de la bilharziose intestinale en milieu scolaire dans les regions de Saint Louis; Matam et Tambacounda au Senegal

Introduction : la bilharziose intestinale est une parasitose qui a toujours sevi dans la partir nord du Senegal; les enfants constituent le groupe d'age le plus expose a cette maladie. Le but de ce travail est de determiner la prevalence de cette pathologie avec comme cible les eleves de la vallee du fleuve Senegal. Materiels et methodes : cette etude s'est deroulee du 10 novembre 2002 au 1er janvier 2003 et a concerne 63 ecoles des regions de Tambacounda; Matam et Saint Louis. Resultats : l'etude n'a concerne que 2.245 eleves sur un effectif total de presque 30 000 eleves dans cette zone; soit un taux d'inclusion de pres de 7;5. Ces eleves ont eu a beneficier d'un examen parasitologique des selles par la technique de Kato/Katz. Parmi les differents departements examines; la bilharziose intestinale a Schistosoma mansoni a ete retrouvee dans seulement 2 departements le long de la vallee du fleuve; a savoir : Richard Toll avec 64 cas sur 318 examines; soit une prevalence de 20; et Kedougou avec 2 cas sur 220; soit 0;9de prevalence. Conclusion : Cette etude realisee le long de la vallee du fleuve; montre une presence de la bilharziose intestinale uniquement a Richard Toll avec une forte prevalence; mais egalement a Kedougou ou les premiers cas sont rapportes dans la partie orientale du Senegal a travers ce travail

Distinct physiological states of Plasmodium falciparum in malaria-infected patients.

Infection with the malaria parasite Plasmodium falciparum leads to widely different clinical conditions in children, ranging from mild flu-like symptoms to coma and death. Despite the immense medical implications, the genetic and molecular basis of this diversity remains largely unknown. Studies of in vitro gene expression have found few transcriptional differences between different parasite strains. Here we present a large study of in vivo expression profiles of parasites derived directly from blood samples from infected patients. The in vivo expression profiles define three distinct transcriptional states. The biological basis of these states can be interpreted by comparison with an extensive compendium of expression data in the yeast Saccharomyces cerevisiae. The three states in vivo closely resemble, first, active growth based on glycolytic metabolism, second, a starvation response accompanied by metabolism of alternative carbon sources, and third, an environmental stress response. The glycolytic state is highly similar to the known profile of the ring stage in vitro, but the other states have not been observed in vitro. The results reveal a previously unknown physiological diversity in the in vivo biology of the malaria parasite, in particular evidence for a functional mitochondrion in the asexual-stage parasite, and indicate in vivo and in vitro studies to determine how this variation may affect disease manifestations and treatment.

[Evaluation of serological tests of toxoplasmosis in pregnant women realized at the Laboratory of Parasitology and Mycology of Le Dantec Teaching Hospital in 2002]. / Bilan des examens sérologiques de la toxoplasmose chez la femme enceinte réalisés au Laboratoire de Parasitologie Mycologe du CHU Le Dantec en 2002.

INTRODUCTION: the toxoplasmosis can occur complications during pregnancy as serious repercussions on the foetus with the risks linked to this pathology such as abortion. However these complications can be avoided during the pregnancy by an early diagnosis. The objective of this study is to determine the prevalence of toxoplasmosis during pregnancy. MATERIALS AND METHODS: we undertook this study on 109 pregnant women addressed to the laboratory of parasitology and mycology of the CHU Dantec for toxoplasmosis serological test on 2002. We used a immunoenzymatic technical in solid phase whose principle rests on the change of coloration in the presence of antibody of IgM or IgG; coloration whose intensity is function of the title of antibody. For that, two serological tests (S1 and S2), starting from two venous blood at 3 weeks of interval, are carried out among these pregnant women. This second serology will make it possible to confirm or cancel an evolutionary toxoplasmosis based on the variation of the title in antibody between the first (S1) and the second serology (S2). A control is carried out among these women among whom the diagnosis of the evolutionary toxoplasmosis was established. RESULTS: they show that with the first (S1), from the 109 patients, 3% were positive with the antibodies IgM type, 22% positive with IgG, and 11% positive with IgG and IgM. 36% of the women present a positive diagnostic at the first serology (S1). The second serology (S2) shows that among the 36% of the women diagnosed positive with the first serology, 11% made an evolutionary toxoplasmosis. CONCLUSION: This study shows a rather significant of serological toxoplasmosis discovered fortuitously among pregnant women at the time of their assessment of pregnancy.

Bilan des examens serologiques de la toxoplasmose

Introduction : la toxoplasmose peut etre a l'origine de complications chez la femme enceinte a type de fotopathies graves; d'avortements. Cependant ces complications peuvent etre evitees pendant la grossesse par un diagnostic precoce. L'objectif de cette etude est de determiner la prevalence de la toxoplasmose chez la femme pendant la grossesse. Materiels et methodes : nous avons mene cette etude sur 109 femmes enceintes adressees au laboratoire de parasitologie et de mycologie du CHU Le Dantec pour un serodiagnostic de la toxoplasmose en 2002. Nous avons utilise une technique immunoenzymatique en phase solide dont le principe repose sur le changement de coloration en presence d'anticorps de type IgM ou IgG; coloration dont l'intensite est fonction du titre en anticorps. Pour cela deux tests serologiques (S1 et S2); a partir de deux prelevements de sang veineux a 3 semaines d'intervalle; sont realises chez ces femmes enceintes. Cette deuxieme serologie permettra de confirmer ou d'infirmer une toxoplasmose evolutive basee sur la variation du titre en anticorps entre la premiere (S1) et la deuxieme serologie (S2). Resultats : ils montrent qu'a la premiere serologie (S1); sur les 109 patientes; 3etaient positives aux anticorps de type IgM; 22positives a IgG; et 11positives a IgG et IgM. Au total 36des femmes presentent un sero- diagnostic positif a la premiere serologie (S1). La deuxieme serologie (S2) montre que parmi les 36des femmes diagnostiquees positives a la premiere serologie; 11faisaient une toxoplasmose evolutive. Conclusion : Cette etude montre une seroprevalence importante de la toxoplasmose decouverte fortuitement chez les femmes enceintes lors de leur bilan de grossesse

Defining the origin of Plasmodium falciparum resistant dhfr isolates in Senegal.

We previously reported a high baseline prevalence of mutations in the dhfr and dhps genes of Plasmodium falciparum throughout Senegal. The highest prevalence of the triple dhfr pyrimethamine associated mutations were found in isolates obtained in the western part of the country near the capital city of Dakar. In this study, we sought out to determine the relatedness of dhfr wild type and mutated strains by analyzing three microsatellite regions upstream of the dhfr locus. Twenty-six of the 31 wild type strains had a unique microsatellite pattern. In contrast, of the 17 isolates containing the triple mutation in dhfr, 11 had an identical microsatellite pattern. Diverse geographical isolates in Senegal containing the triple dhfr mutation have arisen from a limited number of ancestral strains. In addition, we demonstrate that these isolates have shared ancestry with the previously reported triple mutation haplotype found in Tanzania, South Africa, and southeast Asia. This common ancestry may have implications for the malaria control strategy for reducing the spread of sulfadoxine-pyrimethamine resistance in Senegal and elsewhere in Africa.

Mutations in Plasmodium falciparum dihydrofolate reductase and dihydropteroate synthase genes in Senegal.

Senegal recently (2004) switched to sulfadoxine-pyrimethamine (SP) with amodiaquine as first line therapy for malaria in response to increasing chloroquine resistance. In anticipation of emerging resistance to SP as a result of this change in drug pressure, we set out to define the baseline prevalence of SP-associated mutations in the dhfr and dhps genes in Plasmodium falciparum using geographically diverse and longitudinally collected samples. A total of 153 blood samples were analysed from patients (5 years or older) with mild malaria after informed consent was obtained. Longitudinal samples were collected between 2000 and 2003 in Pikine, a suburb of Dakar. Geographically diverse site sampling was carried out in 2003. The mutation prevalence in DHFR codons 51, 59 and 108 is 65%, 61% and 78% in Pikine, 2003. The overall prevalence of the triple mutation that is associated with high-level pyrimethamine resistance is 61%. The mutation prevalence rate in DHPS codons 436 and 437 is 21% and 40%, respectively. There is significant geographic variation in genotypic resistance, as samples from Pikine in 2003 had higher mutation prevalence in the pfdhfr and pfdhps genes compared to samples from Tambacounda (P < 0.015). In summary, this study demonstrates a high background prevalence of SP resistance mutations already present in P. falciparum in Senegal.