F. Cheikhrouhou

Pathogenic free-living amoebae: Epidemiology and clinical review

Free-living amoebae are widely distributed in soil and water. Small number of them was implicated in human disease: Acanthamoeba spp., Naegleria fowleri, Balamuthia mandrillaris and Sappinia diploidea. Some of the infections were opportunistic, occurring mainly in immunocompromised hosts (Acanthamoeba and Balamuthia encephalitis) while others are non opportunistic (Acanthamoeba keratitis, Naegleria meningoencephalitis and some cases of Balamuthia encephalitis). Although, the number of infections caused by these amoebae is low, their diagnosis was still difficult to confirm and so there was a higher mortality, particularly, associated with encephalitis. In this review, we present some information about epidemiology, ecology and the types of diseases caused by these pathogens amoebae.

Epidemiology of dermatophytoses in Sfax, Tunisia.

The distribution of dermatophytes varies in different countries and geographical areas depending on several factors. To determine the frequency of aetiological agents and the clinical variants of dermatophytoses, we carried out a study between 1998 and 2007. Out of 25 432 subjects suspected to have superficial mycoses, 9960 (39.2%) were affected with dermatophytoses; 14957 positive samples were obtained. The mean age was 35.7 years (range: 21 days to 97 years). Sex ratio was 0.9. Our patients were from urban regions in 81.9% of cases. The most common type of infection was onychomycosis (30.3%), followed by tinea pedis (24.8%), intertrigo (21.7%), tinea corporis (11.4%) and tinea capitis (9.6%). Fifteen patients had generalised dermatophytosis. Hadida and Schousboe disease was diagnosed in one case with lethal evolution. The most isolated dermatophyte was Trichophyton rubrum (74.5%), followed by T. violaceum (7.9%), T. mentagrophytes (7.5%), Microsporum canis (3.8%), Epidermophyton floccosum (0.7%) and T. verrucosum (0.54%). Other species were occasionally isolated: T. schoenleinii, T. tonsurans, M. audouinii and M. ferrugineum. The prevalence of dermatophytoses remains high in our country (996 cases/year). Trichophyton rubrum is the predominant causal agent. However, zoophilic agents become more prevalent. Epidemiological surveys are an essential tool for developing strategies for infection control.

Invasive aspergillosis: epidemiology and environmental study in haematology patients (Sfax, Tunisia)

Invasive aspergillosis (IA) is a major opportunistic infection in haematology patients. Preventive measures are important to control IA because diagnosis is difficult and the outcome of treatment is poor. We prospectively examined the environmental contamination by Aspergillus and other fungal species and evaluated the prevalence of invasive aspergillosis in the protect unit of haematology. A three‐year prospective study (December 2004–September 2007) was carried out in the department of haematology of Hedi Chaker Hospital. Suspected invasive aspergillosis cases were reviewed and classified as proven, probable and possible invasive aspergillosis using the EORTC criteria. During the study period, we collected weekly environmental samples (patient’s rooms, tables and acclimatisers) and clinical samples from each patient (nasal, expectoration and auricular). Among 105 neutropenic patients, 16 had probable and 13 had possible IA. A total of 1680 clinical samples were collected and A. flavus was most frequently isolated (79.2%). Analysis of 690 environmental samples revealed that Penicillium (44%) was the most frequent followed by Cladosporium (20%), Aspergillus spp. (18%) and Alternaria (13%). The PCR‐sequencing of 30 A. flavus isolates detected from clinical and environmental samples confirmed the mycological identification. Our findings underline the importance of environmental surveillance and strict application of preventive measures.

Epidemiological survey of vulvovaginal candidosis in Sfax, Tunisia

Vulvovaginal candidosis (VVC) is a common infection of the female genital tract affecting 75% women at least once in their lifetime. The aim of this study was to determine the incidence and potential risk factors associated with VVC and recurrent vulvovaginal candidosis (RVVC). A prospective study of women with vaginitis symptoms was conducted over 2 years in the regional clinic of population and family education in Sfax. A discriminant analysis was used to evaluate the association between the incidence of Candida vaginitis and potential risk factors. Sporadic and recurrent VVC were documented respectively in 48% and 6.1%. The most frequent factors associated with positive Candida culture were employed women, uncontrolled diabetes, history of genital infection and intrauterine device contraception. Increased episode numbers of VVC and condom/spermicidal contraception were positively associated with recurrences. Candida albicans was the predominantly isolated species (76.3%) followed by Candida glabrata (19.3%). Infection with C. glabrata occurred in 34% and 17.5% of patients with RVVC and VVC respectively. The discriminant investigation had provided further insights into the basis for prevention and control of RVVC. Increased prevalence of C. glabrata in patients with RVVC and observed risk factors should be taken into consideration to achieve success in the management of this infection.

Clinical utility and prognostic value of galactomannan in neutropenic patients with invasive aspergillosis

UNLABELLED Invasive aspergillosis (IA) is a major cause of morbidity and mortality in profoundly neutropenic patients. Delayed diagnosis and therapy may lead to poor outcomes. AIMS The objective of this study was to assess the performance characteristics of the galactomannan (GM) assay in serum and bronchoalveolar lavage specimens for the diagnosis of IA in neutropenic patients with hematological malignancies. We also evaluated the prognostic outcome. PATIENTS AND METHODS A total of 1198 serum samples and 42 BAL from 235 neutropenic patients were tested with a GM elisa platelia test. We used Cox modeling of time to 6- and 12-week mortality for GM level at the time of diagnosis (GM0) and GM decay in the week following diagnosis in proven and probable IA patients with more than two GM values. RESULTS There were three proven, 55 probable, and four possible cases of IA. The sensitivity and specificity of the GM test were 96.8% and 82.4% respectively. In BAL samples, sensitivity was 86% and the specificity 93%. BAL GM was more sensitive than microscopy (22.2%) and BAL culture (38.9%). Among patients with proven/probable IA, serum and BAL GM were in agreement for 92.8% of paired samples. The hazard ratio (HR) of GM0 and 1-week GM decay per unit increase in Aspergillus enzyme immunoassay (EIA) was 1.044 (95% CI, 0.738 to 1.476) and 0.709 (95% CI, 0.236 to 2.130) respectively. CONCLUSION We found good correlation between the GM0 and GM decay combination and outcome of IA patients. The GM is a useful tool for diagnosis and monitoring of IA.

Invasive fungal infections in renal transplant recipients: About 11 cases

UNLABELLED Invasive fungal infections are a major complication and an important cause of morbidity and mortality among solid organ transplant recipients. Their diagnosis is difficult and their prognosis is often pejorative. OBJECTIVE The aim of this study was to report the cases of invasive fungal infections in renal transplant recipients in Habib Bourguiba Sfax university hospital and to identify the main fungal agents. MATERIALS AND METHODS It is a retrospective study of invasive fungal infections in renal transplant recipient reported in our hospital from January 1995 to February 2013. RESULTS Invasive fungal infections were diagnosed in 11 cases (3.4%) among 321 renal transplant recipients. These infections included four cases of pneumocystosis, two cases of candidiasis, two cases of aspergillosis, two cases of cryptococcosis and one case of mucormycosis. There were six men and five women. The mean age was 37 years. The infection was late in 63% of cases (>3 months after transplantation). The prolonged corticosteroid and immunosuppressive therapy were the main risk factors (100%) followed by renal failure (45%), graft rejection (45%), broad spectrum antibiotics (45%), CMV infection (36%), neutropenia (36%) and dialysis (18%). The evolution under treatment was favourable only in two cases (18%). CONCLUSION Invasive fungal infections are not common among kidney transplant recipients. However, they remain an important cause of morbidity and mortality in this group of patients. Prevention, early diagnosis and appropriate management are necessary to improve prognosis and reduce mortality rate.

Ethnic and socio-cultural specificities in Tunisia have no impact on the prevalence of anti-Saccharomyces cerevisiae antibodies in Crohn's disease patients, their relatives or associated clinical factors.

Background. In Western Europe and the USA, the presence of anti-Saccharomyces cerevisiae antibodies (ASCAs) in Crohns disease (CD) patients and their healthy relatives suggests that ASCAs may be influenced by genetic and/or environmental factors. Objectives. To assess the prevalence of ASCAs in Tunisian patients with CD or ulcerative colitis (UC), and unaffected family members, in relation to clinical phenotype. Patients and methods. Seventy-seven patients (39 CD, 38 UC), 66 healthy relatives of CD patients, 16 relatives of UC patients and 70 healthy controls were studied. ASCAs were quantified with a new isotype-specific ELISA test involving an antigenic extract from S. cerevisiae strain W303 and by the original test which detects total immunoglobulins against S. cerevisiae Su1 mannan. Results. The specificity of the two tests was identical (91%). The isotype-specific ASCA W303 test was more sensitive than the ASCA Su1 test for immunoglobulin detection, but some CD patients were positive only with this latter test. A high percentage of patients with CD (72%) and their unaffected family members (35%) were ASCA-positive in contrast to UC patients (16%) and their relatives (0%) and controls (8.6%). ASCAs were shown to be independent of rural or urban living, disease activity, but were associated with ileal location. The antigen of S. cerevisiae strain W303 discriminated patients depending on age at onset or location of the disease. Conclusion. This study confirms the antigenic heterogeneity of S. cerevisiae strains in their ability to detect ASCA. It suggests that ASCAs are markers of immunoregulatory disturbance in CD, independently of ethnic/cultural differences between Europe, the USA and North Africa.

Epidemiological profile of fungal keratitis in Sfax (Tunisia).

UNLABELLED Fungal keratitis is responsible for a significant burden of blinding disease in the developing world. OBJECTIVE The aim of this study was to determine the etiological agents, predisposing factors and therapy of keratomycosis in our region. METHODS Retrospective study of 60 patients with clinically and cultured confirmed fungi keratitis, who were attended at department of mycology in Sfax (1995 to 2012). RESULTS The mean age of patients was 47.2 years (sex ratio: 1.58). At least, one presumed predisposing factor was identified in 83.3% of cases. Corneal traumatism was established as the most common predisposing factor (61.6%) with vegetative matter (42.4%). Patients had corneal ulcer in 40% or abscess in 47.6%. All cases were positive on direct microscopy and 93% of cultures were positive. Filamentous fungi form the major etiologic agents (83%): Fusarium species (49% with F. solani [66%]), Aspergillus sp. (22%), Alternaria (5%), Scedosporium sp. (2%); and non-identified mold in (5%). Yeast were identified in 17% of cases. Topical agents were used in 97% of cases: ketoconazole 2%, amphotericin B (0.5%). Fluconazole per os was administrated for 11% of cases, itraconazole (2 cases) and voriconazole (one case). Keratoplasty was indicated for 27% of cases. The outcome was favorable in 16% of patients. Among the patients, 71% had persistent corneal deposit sequelae. Four patients lost the eyeball. CONCLUSION Corneal traumatism was the principal risk factor for fungal keratitis in young and middle-aged farmers. Fusarium solani is the predominant cause in Sfax. Early diagnosis, coupled with appropriate treatment, is crucial for increasing the chance of complete recovery.

Two new media Pinus halepensis seed agar and blackberry agar for rapid identification of Cryptococcus neoformans

Cryptococcus neoformans is an encapsulated yeast‐like fungus that causes life‐threatening infections, particularly in immunocompromised patients. The formation of brown pigment on many media described in the literature, such as that in Niger seed (Guizotia abyssinica) agar, has been used to identify C. neoformans. The present study compares melanin production by clinical and environmental isolates of C. neoformans and other medically important yeast on two new media, Pinus halepensis seed (PHS) agar and blackberry (BlaB) agar, and the classic medium Niger seed agar. Results obtained after the culture of 46 strains of C. neoformans, for 4, 24 and 48 h at 37 °C on these three media, showed that at 24 h, 100% of strains were pigmented on BlaB agar, 91.3% on PHS agar but only 34.8% on Niger seed agar. In conclusion, PHS and BlaB agar are two interesting new media for the rapid identification of C. neoformans isolates.

Childhood dermatomycoses study in Sfax hospital, Tunisia

Mycoses are frequent affections in childhood. Fungal type varies according to the age and the affected organ. The aim of this study was to determine the aetiological agents of childhood dermatomycoses and to draw attention to the diversity of their clinical manifestations. Retrospective study dealing with children’s cases with age <16‐year old and having dermatomycosis diagnosed between 1991 and 2005 at the Parasitology and Mycology Laboratory of Sfax University Hospital. A total of 4559 children suspected to have superficial mycoses were examined. Dermatomycosis diagnosis was confirmed in 49.3% of cases. Dermatophytes were the most prevalent fungal agents and accounted for 1865 cases (80.6%) dominated by Trichophyton violaceum (54.1%) and Microsporum canis (24.5%). Tinea capitis (69.4%) was the most common type of infection, followed by tinea corporis (20%). Superficial yeast infections (442 cases) were dominated by Malassezia infections (71%). Candida infections were mainly due to Candida albicans (58%). The clinical features of paediatric dermatomycoses vary with the age of the children: tinea capitis and tinea corporis were more frequent before 13 years of age. After this age, tinea versicolor and onychomycoses became more common.