ABSTRACT
OBJECTIVE: To determine the epidemiological and etiological profile of tinea capitis in adults in Dakar (Senegal). PATIENTS AND METHODS: A 9-month prospective, multicenter, descriptive and analytic study. Patients included were aged over 18 years. Mycological tests were used to confirm the diagnosis. RESULTS: 121 patients were included with a mean age of 36.1 years and a hospitalisation frequency of 0.8%. The age range of 64.4% of patients was between19 and 38 years. 51% of patients were housewives. A low socioeconomic level was found in 72.8% of cases. In 3.3% of patients, the disease began in childhood. 31.4% of patients had already consulted a traditional healer. Similar familial cases were noted in 60.3% of patients. Contact with a sheep was noted in 32.2% of cases, deliberate skin lightening in 64% of women, hair salon attendance in 46.7% of women, and immunosuppression in 17.3% of patients, while itching was present in 95.5%. Dermatologic examination showed scaled plaques and a diffuse form, with 92.6% and 64% (n=75) respectively. Wood's light examination was positive in 40.2% of patients. A positive culture test was found in 71%. The most frequently encountered species were: T. soudanense (65%), M. audouinii (21%), T. rubrum (4.7%), M. gypseum (3.5%), T. violaceum (2.3%), T. verrucosum (2.3%) and M. canis (1 case). The clinical course was favorable under treatment with griseofulvin or terbinafine. CONCLUSION: Tinea capitis in adults mainly affects young women. The diffuse form is the most common. The most frequently encountered species was T. soudanense.
Subject(s)
Tinea Capitis/epidemiology , Tinea Capitis/microbiology , Adult , Aged , Antifungal Agents/therapeutic use , Cross-Sectional Studies , Delayed Diagnosis , Female , Griseofulvin/therapeutic use , Humans , Male , Middle Aged , Prospective Studies , Senegal/epidemiology , Socioeconomic Factors , Terbinafine/therapeutic use , Tinea Capitis/drug therapy , Young AdultABSTRACT
The authors report the case of a 22-year-old man referred seven months after the onset of papulo-nodular skin lesions, lymphadenopathy, splenomegaly and hepatomegaly. Mycologic and histologic examination of skin lesions enabled the diagnosis of African histoplasmosis, by Histoplasma capsulatum var duboisii. The lymph nodes were caseous. The culture in Lowenstein-Jensen medium was negative.
Subject(s)
Histoplasmosis/diagnosis , Lymphadenopathy/diagnosis , Lymphadenopathy/microbiology , Humans , Male , Senegal , Young AdultSubject(s)
Leishmaniasis, Cutaneous/pathology , Skin Ulcer/pathology , Skin Ulcer/parasitology , Adult , Humans , Immunocompetence , Male , Rare Diseases , Senegal , Sporotrichosis/diagnosisABSTRACT
Our aims were to study the epidemiological, clinical, and parasitological aspects of cutaneous leishmaniasis in the dermatology department of the Aristide Le Dantec hospital. This retrospective study reviewed records of cases treated over a 4-year period (from April 2010 through April 2014) at the HALD Dermatology department. The study included all patients with cutaneous leishmaniasis during the study period. The diagnostic criteria were clinical, parasitological, and histological. The study included 38 patients, corresponding to 9.5 cases per year. Patients' average age was 25 years (4-65 years) and the sex ratio was 1.6. The mean time from symptom outset to consultation was 3.2 months. The disease was located in limbs in 23 cases (63.8%), the face in 6 cases (16.6%), and disseminated in 9 (19.6%). The clinical presentation was ulcerated and crusted in 17 patients (44.7%), sporotrichoid in 13 (28.9%), pseudo-lepromatous in 4 (10.5%), and lupoid in 3 cases (7.9 %). It included warts, mucosa, and tropical sores (Aleppo boils) in all cases. We observed 3 cases associated with HIV; one had a pseudo-lepromatous presentation and resulted from immune restoration syndrome, while two patients had clinical forms of associations: ulcerative and crusted lesions associated with mucosal leishmaniasis in a 55-year-old patient, and cutaneous ulcerative, lupoid, and crusted multifocal (cutaneous, medullary, and lymph nodes) lesions in a 4-year-old infected with Leishmania infantum. Crusted ulcerative cutaneous leishmaniasis is the predominant form of cutaneous leishmaniasis. Infection with HIV can be an important factor in clinical and parasitological atypia.
Subject(s)
Leishmaniasis, Cutaneous , Adolescent , Adult , Aged , Child , Child, Preschool , Female , Hospitals, University , Humans , Leishmaniasis, Cutaneous/diagnosis , Leishmaniasis, Cutaneous/epidemiology , Leishmaniasis, Cutaneous/parasitology , Male , Middle Aged , Retrospective Studies , Senegal , Young AdultABSTRACT
Les manifestations cutanées au cours de l'infection à VIH étaient beaucoup rapportées, celles du cuir chevelu l'étaient moins. Notre objectif était de déterminer les types de dermatoses du cuir chevelu survenant au cours de l'infection à VIH. Une étude prospective était menée sur 10 mois (juillet 2008 - avril 2009) dans des structures de prise en charge de personnes vivant avec le VIH à Dakar. Était inclus, tout patient infecté par le VIH présentant une atteinte du cuir chevelu et suivi dans l'un des sites de l'étude durant la période de l'étude. Un total de 63 patients présentant 85 pathologies du cuir chevelu était colligé, dont 65 % de sexe féminin et 35 % de sexe masculin. L'âge moyen était de 38 ans. La prévalence des atteintes du cuir chevelu était de 5,7 % à la clinique dermatologique de l'hôpital Aristide Le Dantec et 22 % au Centre de Traitement ambulatoire (CTA) du CHU de Fann. La trichopathie soyeuse représentait 32 % des pathologies, la teigne 24 %, la dermite séborrhéique 15 %. La trichopathie soyeuse, était associée au stade C chez 19 patients et au stade B chez 8 patients. Parmi les 20 patients ayant la teigne, 8 patients avaient moins de 200 CD4/mm3. Le délai moyen avant le recours au soin était de 74 jours. L'atteinte du cuir chevelu entrainait un retentissement psychologique chez 63 % des patients. Le cuir chevelu était atteint en cas d'immunodépression sévère et de dénutrition importante
Subject(s)
Scalp , Scalp DermatosesABSTRACT
INTRODUCTION: The etiologies of intertrigo in adults are numerous and different. The objective of our work was to study the epidemiological, clinical and the risk factors of intertrigo in adults. METHODS: We conducted a prospective study for a period of seven months in two Dermatology Units in Dakar (Senegal). All adults patient with intertrigo seen during this period who gave consent were included. RESULTS: One hundred and three patients with intertrigo were diagnosed with a hospital prevalence of 2.54%. The sex -ratio was 0.63 and the average age was 41. The study of habits and lifestyles of the patients found a history of intensive skin lightening, sport, wearing synthetic clothes and smoking in 26, 22, 20 and 22 cases, respectively. Infectious complications mainly bacterial (3.88%) and viral (1.94%) were reported in nine cases (8.7%). A dry erythroderma was noted in 3 cases (2.9%). It was found that the intertigo was commonly caused by fungal infections with a prevalence of 48.5% followed by immuno-allergic reactions with a prevalence of 34.9%, suppurative hidradenitis and inverse psoriasis with the same prevalence of 2.9%. Fifty-eight percent of cases with tinea and 63% of cases with candidiasis were women. Thirty-five percent of tinea cases and 45% of candidiasis cases were found to have a history of intensive skin lightening. CONCLUSION: The cause of intertrigo in adults are mainly infectious, particularly fungi, infections and immuno-allergic diseases. There are predisposing factors and some professions are more at risk.
Subject(s)
Intertrigo/epidemiology , Intertrigo/etiology , Mycoses/epidemiology , Mycoses/etiology , Adolescent , Adult , Age Factors , Aged , Disease Progression , Female , Humans , Intertrigo/microbiology , Male , Middle Aged , Mycoses/microbiology , Prevalence , Psoriasis/epidemiology , Risk Factors , Senegal/epidemiology , Tinea/epidemiology , Young AdultABSTRACT
INTRODUCTION: Endodontic flora is dominated in the apical part of the channels by strict anaerobic and some facultative anaerobic bacteria but also by Candida yeasts, especially Candida albicans species that are involved in the maintenance and persistence of endodontic infections. Their elimination of the canal system in practice by chemo-mechanical methods of disinfection is not always guaranteed. Thus, this in vitro study was performed to determine the sensitivity of C. albicans with sodium hypochlorite (NaOCl) dosed at 2.5 %, the chlorhexidine digluconate 0.5 % and calcium hydroxide used in inter-session medication. METHODS: The diffusion method was used initially to test the sensitivity of C. albicans strains with the above products. Then a dilution technique has allowed us to determine the minimum inhibitory concentration of these active products on C. albicans. RESULTS: Strains from infected pulp teeth of patients showed a sensitivity of C. albicans to sodium hypochlorite to a minimum inhibitory concentration less than 70µg/mL and 30µg/mL for chlorhexidine. CONCLUSION: This study demonstrated a sensitivity of C. albicans to sodium hypochlorite and chlorhexidine.
Subject(s)
Calcium Hydroxide/pharmacology , Candida albicans/drug effects , Chlorhexidine/analogs & derivatives , Disinfectants/pharmacology , Sodium Hydroxide/pharmacology , Anti-Infective Agents, Local/pharmacology , Candida albicans/growth & development , Candida albicans/isolation & purification , Chlorhexidine/pharmacology , Drug Combinations , Humans , Microbial Sensitivity Tests , Mouth Mucosa/microbiologyABSTRACT
BACKGROUND: In Senegal, reported cases of cutaneous leishmaniasis are often due to Leishmania major. Immunosuppression related to HIV infection contributes to the emergence of leishmaniasis in humans and to cutaneous localization of viscerotropic species. We report the first observed case in Senegal of opportunistic cutaneous leishmaniasis due to Leishmania infantum associated with HIV. PATIENTS AND METHODS: A 5-year-old boy presented crusted ulcerative lesions of the scalp and left forearm, together with axillary and cervical lymphadenopathy present for two months. Direct parasitological examination of the scalp and arm lesions, coupled with liquid aspiration of lymph nodes and bone marrow, enabled identification of amastigote forms of Leishmania. Polymerase chain reaction performed on skin, lymph node and bone marrow biopsy samples allowed identification of L. infantum. The child was positive for HIV1. Treatment of HIV infection and leishmaniasis resulted in clinical improvement. DISCUSSION: Co-infection with cutaneous leishmaniasis due to L. infantum and HIV is a complex combination in terms of the related therapeutic issues. The clinical and laboratory outcomes depend on restoration of immunity and on the efficacy, safety and availability of anti-leishmaniasis drugs.
Subject(s)
AIDS-Related Opportunistic Infections/diagnosis , HIV Infections/complications , Leishmania infantum/isolation & purification , Leishmaniasis, Cutaneous/diagnosis , Child, Preschool , Humans , Leishmaniasis, Cutaneous/complications , Male , SenegalABSTRACT
The authors report a case of multifocal African histoplasmosis with polymorphic skin involvement occuring in a patient without proven immunosuppression. He was a young 22-year-old patient from eastern Senegal - but born in Ouganda - who presented with polymorphic skin lesions: ombilicated papulo-nodules, gums and ulcerative and budding lesions. He showed lymphadenopathies without clinical inflammation and with a cheesy appearance of the biopsy but without tuberculosis and also hepatosplenic and bone involvement. Mycological samples of the skin and lymph nodes biopsies revealed yeasts of Histoplasma capsulatum var. duboisii with a positive culture on Sabouraud medium. HIV serology, HTLV1et 2, the serum proteins electrophoresis were unremarkable. Treatment with amphotericin B was irregular because of its inaccessibility in the national territory and its cost. The patient died of sepsis together with the aggravation of his disease.
Subject(s)
Histoplasma/isolation & purification , Histoplasmosis/diagnosis , Histoplasmosis/microbiology , Immunocompetence , Fungemia/diagnosis , Fungemia/microbiology , Histoplasmosis/pathology , Humans , Male , Senegal , Young AdultABSTRACT
INTRODUCTION: Endodontic infections are characterized by their microbial polymorphism with the presence of pathogenic agents such as bacteria. The aim of this study was to investigate the presence of yeast in the root canals of teeth with pulp necrotic with or without apical periodontitis and to study the sensibility of these at disinfection at sodium hypochlorite to 2.5 %. METHODS: Root canal samples, taken with paper points before and after disinfection with sodium hypochlorite dosed at 2.5 % on 50 single rooted teeth in 38 patients, were seeded in petri dishes containing Sabouraud Chloramphenicol (SC) (Conda Laboratories, Madrid). These stains were incubated in an incubator at 37°C for 48hours. The presence of yeast was confirmed by white colonies on the entire circumference of the tip paper. The identification of species was done by macroscopic and microscopic examinations associated with Blastese test. RESULTS: The yeast colonies were isolated from 7 teeth (14 %) out of 50. All positive samples were from teeth with an open necrotic pulp (P<0.001). The only species found was Candida albicans. Immediate disinfection with sodium hypochlorite at 2.5 % did not show a complete elimination of yeasts. CONCLUSION: The results of this study show that the canal of necrotic teeth with or without apical periodontitis may shelter yeasts even after immediate disinfection with sodium hypochlorite 2.5 %.
Subject(s)
Dental Pulp Necrosis/microbiology , Periapical Periodontitis/microbiology , Sodium Hypochlorite/pharmacology , Yeasts/drug effects , Yeasts/isolation & purification , Adolescent , Adult , Aged , Candida albicans/drug effects , Candida albicans/isolation & purification , Child , Disinfection/methods , Female , Humans , Male , Microbial Sensitivity Tests , Middle Aged , Senegal , Therapeutic Irrigation , Young AdultABSTRACT
BACKGROUND: In Africa, studies primarily devoted to chronic leg ulcer due to sickle cell disease are rare. The objectives of the study were to determine the epidemiology, diagnosis and progression of chronic leg ulcers in sickle cell disease. PATIENTS AND METHODS: A 5-year multicentre, retrospective study was conducted in three university hospitals in Dakar. We included all patients with chronic leg ulcers occurring in a setting of sickle cell disease. RESULTS: We identified 40 cases of chronic leg ulcers associated with sickle cell disease, representing 3.4% of the current population of sickle cell patients in our institutions. The average patient age was 25.9 years and the sex ratio was 2.33. Chronic leg ulcer was the presenting feature enabling diagnosis of sickle cell disease in one third of the cases. The average time to consultation from onset was 5.4 years. Pain was reported in 22 cases (48%). Ulcers were isolated in 76% and multiple in 24% of cases. The most common site was the medial malleolus (39%). A CBC allowed identification of anaemia in 35 cases. Haemoglobin electrophoresis was performed and homozygous sickle cell SS disease was identified in 39 cases and heterozygous SC disease in 1 case. Local treatments included physiologic serum, topical antibiotics and skin grafting. Systemic treatment included supplementation with folic acid in all patients, blood transfusion in 16 cases, vasodilators in 11 cases and antibiotics in 25 cases. The outcome was favourable in 61.8% of cases. DISCUSSION: In Dakar, sickle cell disease is a common cause of chronic leg ulcer and is frequently revealed by chronic leg ulcer.
Subject(s)
Anemia, Sickle Cell/complications , Leg Ulcer/etiology , Adolescent , Adult , Anemia, Sickle Cell/diagnosis , Anemia, Sickle Cell/epidemiology , Child , Female , Humans , Leg Ulcer/epidemiology , Leg Ulcer/therapy , Male , Middle Aged , Retrospective Studies , Senegal/epidemiology , Young AdultABSTRACT
Use of medicinal plants is common and widespread throughout Africa, including in Senegal. Because efficacy has been demonstrated, public policies have been instituted that have allowed plant-based therapies to have an important role in general primary care. However, little is known about the cutaneous safety of many plant-based therapies. In this 6-month prospective study all cases of dermatitis induced or aggravated by exclusive use of medicinal plants were evaluated via skin allergy testing. The results were classified and compared with the available literature. Forty-three cases of plant-therapy-associated cutaneous reactions were identified, including worsening of existing conditions (56%), recurrence of a previously resolved condition (16%) and new dermatitis arising spontaneously (28%). In the cases where the condition was new, generalized exfoliative dermatitis occurred in 42% of cases with an average time of onset of 9 days. Specific plants were identified in 65% of cases and included 18 varieties. The frequency and severity of plant-induced cutaneous reactions should be the basis for the creation of a phytovigilance programme and re-evaluation of how traditional medicine is used in the general population. When irritation occurs, identification of the responsible plant and allergy testing should be the first steps towards relieving symptoms.
Subject(s)
Dermatitis, Atopic/chemically induced , Drug Eruptions/etiology , Plants, Medicinal/adverse effects , Dermatitis, Atopic/epidemiology , Drug Eruptions/epidemiology , Humans , Phytotherapy/adverse effects , Prospective Studies , Senegal/epidemiology , Skin TestsABSTRACT
Mycetomas are localized chronic inflammatory infectious diseases involving subcutaneous tissues, skin and bones. We report a case of mycetoma in a 40-year-old farmer from the north of Senegal. The clinical appearance of the lesions suggested primarily the diagnosis of a soft tissue malignant tumor. Mycetoma diagnosis was confirmed by histopathologic evidences and growth of Actinomadura pelletieri in cultured samples. The evolution was good under a triple antibiotic therapy combining cotrimoxazole, amoxicillin-clavulanic acid and streptomycin for 12 months.
Subject(s)
Actinomycosis/diagnosis , Mycetoma/diagnosis , Adult , Back , Diagnosis, Differential , Female , Humans , Lumbosacral Region , SenegalABSTRACT
The aim of our study was to determine the epidemiological and clinical aspects of vitiligo in the largest dermatology department of Senegal. A cross-sectional and descriptive study in a period of 5 months was performed covering all the vitiligo cases. Fifty patients were identified (26 women and 24 men). The mean age was 26.5 years. A family history of vitiligo was found in 11 cases and a psychoaffective disturbance in 6 cases. The clinical forms distinguished were generalized vitiligo (n = 33), localized vitiligo (n = 16), vitiligo universalis (n = 4), and segmental vitiligo (n = 1). The Koebner phenomenon was found in 7 cases. Associated diseases were atopic dermatitis (n = 2), contact dermatitis (n = 1), diabetes (n = 1), and Graves' disease (n = 1). The disgraceful character of Vitiligo was the predominance of generalized forms and the elective localization in sun-exposed areas. The family character, the psychoaffective disturbances, the Koebner phenomenon increased by the lifestyle and the itching dermatosis were the aggravating factors.
ABSTRACT
BACKGROUND: Cutaneous schistosomiasis is extremely rare, even in endemic regions. It usually leads to non-specific papulonodular lesions in the perigenital area. We report a case of cutaneous schistosomiasis presenting as panniculitis. CASE REPORT: An 8-year-old girl was admitted for a large multinodular, indurated plaque over the perineum that gradually spread over a year in a setting of hypereosinophilia. Ultrasonography showed thickening of the bladder and a significant bilateral ureteral hydronephrosis. Histological examination revealed numerous granulomas Schistosoma haematobium ova at their centre and within the hypodermis. Treatment with praziquantel 40 mg/kg resulted in regression of cutaneous lesions within 3 weeks. DISCUSSION: We report a case of Schistosoma-induced granulomatous panniculitis that is noteworthy in terms of its clinical appearance, perineal location, association with severe urinary involvement and rapid regression under treatment. The current extent of endemic schistosomiasis and its severity justify greater awareness of this unusual cutaneous presentation, which to our knowledge has never previously been reported.
Subject(s)
Granuloma/diagnosis , Granuloma/parasitology , Panniculitis/diagnosis , Panniculitis/parasitology , Schistosomiasis/diagnosis , Skin Diseases, Parasitic/diagnosis , Child , Female , Granuloma/complications , Humans , Panniculitis/complicationsABSTRACT
INTRODUCTION: Mycetoma is chronic inflammatory process characterized by areas of tumefaction with draining sinus tracts. It affects the foot in 80% of cases. The purpose of this report is to describe a case that posed a diagnostic challenge due to unusual scalp location and clinical presentation. OBSERVATION: A 23-year-old woman residing in a rural zone of Senegal consulted for indolent lesions ongoing on the scalp for 2 years. Physical examination showed two soft tumid lesions measuring about 3 cm in diameter on the vertex. The surface of the lesions was crusty but showed no sign of granules. Skull x-ray was normal. Skin biopsy demonstrated a polymorphous granulomatous infiltrate with foci of suppuration circumscribing small, irregular grains with radiating filaments. Mycological culture on Lowenstein medium demonstrated Actinomadurella pelletiere. Treatment with cotrimoxazole for 8 months led to significant regression of the lesions. DISCUSSION: The mycetoma described in this report posed a diagnostic challenge because of its unusual scalp location and especially its tumoral or pseudo-cystic presentation. This clinical form of mycetoma must be taken into account for diagnosis in any patient from endemic areas.
Subject(s)
Actinomycetales Infections/diagnosis , Actinomycetales/isolation & purification , Mycetoma/diagnosis , Scalp Dermatoses/diagnosis , Actinomycetales Infections/complications , Actinomycetales Infections/drug therapy , Adult , Anti-Infective Agents/therapeutic use , Female , Humans , Mycetoma/drug therapy , Mycetoma/microbiology , Scalp Dermatoses/drug therapy , Scalp Dermatoses/microbiology , Time Factors , Treatment Outcome , Trimethoprim, Sulfamethoxazole Drug Combination/therapeutic useABSTRACT
INTRODUCTION: We report two cases of squamous cell carcinoma (SCC) in two black women (phenotype VI) using bleaching compounds for cosmetic purposes over a period of 15 years. CASE REPORTS: Two women (aged 45 and 47 years) with a long history of cosmetic use of bleaching compounds consulted at a dermatology unit for skin tumours. A diagnosis of SCC was confirmed by histological examination of tumour biopsies. One patient was HIV-positive. Surgical treatment was performed in both cases: simple postoperative complications were seen in one patient but the other died at home following recurrence of carcinoma in the year following diagnosis. DISCUSSION: To our knowledge, theses two cases represent the first description of SCC occurring after prolonged cosmetic use of bleaching compounds. Carcinoma occurred in both cases in skin exposed to sun. In our patients, the mechanism of carcinogenesis may have involved melanin destruction, solar exposure and corticosteroid-induced immunosuppression. A direct carcinogenic effect of hydroquinone or other unidentified compounds is another possibility; the carcinogenicity of hydroquinone is well established in rodents. While these observations do not provide formal proof of any implication of depigmentation products in SCC, they emphasize the need for monitoring of dark-skinned women using skin lighteners.
Subject(s)
Carcinoma, Squamous Cell/chemically induced , Cosmetic Techniques/adverse effects , Skin Neoplasms/chemically induced , Sodium Hypochlorite/adverse effects , Administration, Topical , Black People , Carcinoma, Squamous Cell/pathology , Carcinoma, Squamous Cell/surgery , Female , Humans , Middle Aged , Senegal , Skin Neoplasms/pathology , Skin Neoplasms/surgery , Skin Pigmentation/drug effects , Sodium Hypochlorite/administration & dosageABSTRACT
Introduction. Le diagnostic de tuberculose cutanee est rendu difficile par son polymorphisme clinique. Notre objectif etait de preciser les donnees epidemiologiques; cliniques; paracliniques et evolutives de la tuberculose cutanee a Dakar. Materiel et methode :Une etude retrospective de Janvier 1972 a Octobre 2005 a ete effectuee au service de Dermatologie de l'Hopital Le Dantec de Dakar. Le diagnostic etait base sur des arguments epidemiologiques; cliniques; l'intradermo-reaction a la tuberculine; la bacteriologie et l'histologie. Resultats : Notre etude a recense 151 cas dont 78 hommes et 73 femmes. La tuberculose cutaneo-ganglionnaire etait majoritaire (84;76) suivie de la gomme (11;25). Le lupus tuberculeux (1;98); la tuberculose periorificielle (1;98); la tuberculose verruqueuse (2;64) et la BCGite (0;66) etaient plus rares. Les localisations viscerales (43) etaient pulmonaires (26;5); osteoarticulaires (8;6) neurologiques (0;66) et multiples (9;17). L'IDR etait fortement positive dans 65;15des cas; la bacilloscopie dans 12;5; l'histologie dans 66;22et la serologie VIH dans 14;28. La cicatrisation des lesions cutanees etait notee chez tous les patients apres 1 a 2 mois de traitement. Une recidive a ete notee dans 3 cas et un deces dans 3 cas chez des patients positifs au VIH. Une guerison a ete observee dans 23 cas apres 8 a 12 mois de traitement. Conclusion : La tuberculose cutanee demeure endemique au Senegal. Le scrofuloderme et la gomme sont les principales formes cliniques. L'IDR fortement positive et le granulome tuberculoide avec necrose caseeuse deviennent des arguments diagnostiques de grande valeur