The antifungal effect of Salvadora persica and Euclea natalensis on Candida isolates from Libyan patients with type 2 Diabetes mellitus.

Philosophiae Doctor - PhD (Medical BioScience)Improved oral hygiene plays a vital role on quality of health and well-being of diabetic patients. Poor oral health leads to an increased incidence of oral diseases, particularly oral candidiasis. The emergence and global spread of azole- resistant Candida species has necessitated the need for novel, cost effective antifungals to stop further spread of resistant Candida infections. This project is the first documented investigation of Candida species prevalence in Libyan type 2 diabetes mellitus (T2DM) patients and investigated the antifungal effect of Salvadora persica and Euclea natalensis on azole-resistant Candida isolates. In this study, 182 Candida isolates from the oral mucosa of T2DM patients were identified using presumptive species identification by chromogenic media followed by confirmation using API ID 32 C, YST Vitek 2 and phenotype microarrays. Their drug susceptibility profiles were tested using the disc diffusion and the AST Vitek 2 compact system. High-pressure liquid chromatography and nuclear magnetic resonance were employed to separate, isolate and purify the bioactive compounds and fractions of the plant extracts which were then tested for their antifungal activity. The results showed that both Salvadora persica and Euclea natalensis promise to provide beneficial alternatives to conventional drugs in treating oral candidiasis in diabetic patients

Vitek characterisation of type 2 diabetes-associated Candida species

Background: Type 2 diabetes mellitus (T2DM) predisposes patients to opportunistic infections, such as invasive candidiasis. Treatment of candidiasis is challenged by the emerging resistance of Candida species. In this study, the antifungal drug resistance patterns of Candida species present in the oral mucosa of T2DM Libyan patients was investigated. Methods: Seventy four (74) oral Candida isolates collected from T2DM patients in Misrata, Libya were characterised using the VITEK 2 Compact system. Results: Prevalent species included C. albicans, C. glabrata, C. dubliniensis, C. krusei, C. tropicalis, C. sake, C. kefyr, C. guilliermondii, C. parapsilopsis, C. membranifaciens and C. magnoliae. Drug susceptibility showed an emerging resistance across representatives of all species for which breakpoints were available, with the exception of C. parapsilopsis. Although there are no established interpretative breakpoints for these species, three C. sake isolates and the C. membranifaciens isolate also had high MIC values for fluconazole. The tested isolates were found to be largely susceptible to caspofungin and micafungin. All C. albicans isolates were susceptible to the echinocandins, amphotericin B and 5-flucytosine. Resistance to more than one drug class was seen in C. dubliniensis, C. glabrata and C. krusei isolates. Conclusion: Although the susceptibility results for the echinocandins were encouraging, resistance against the azoles was apparent and should not be ignored. This was especially so in the case of fluconazole, which is often the only locally available antifungal drug for the treatment of disseminated candidiasis.This study was supported financially by the Libyan Government

Candida species carriage in diabetic patients in Misrata, Libya

Background: There is a paucity of studies describing the prevalence and antimicrobial profiles of Candida in Libya. Limited treatment choices in the antifungal armamentarium in public healthcare settings in Africa require a study of the prevalence and susceptibility of Candida species in Libya, where antifungals are not routinely prescribed in public healthcare settings. Methods: In this study, 170 diabetes mellitus type 2 (T2DM) patients were examined for Candida carriage in the oral mucosa, using differential Fluka and Oxoid chromogenic media and API 32 ID C biochemical testing. Fluconazole susceptibility was investigated by disk diffusion on YNBG agar. Isolates were graded as susceptible, intermediate or resistant according to their inhibition zone measurements and microcolony scores. Results: Thirteen species were identified from 182 isolates with a frequency of 68 C. albicans, 42 C. dubliniensis, 26 C. humicola, 20 C. glabrata , 5 isolates of each C. krusei, C. tropicalis and C. kefyr, 4 C. sake, 2 C. parapsilopsis, 2 C. magnoliae and 1 isolate each of C. guilliermondii, C. globosa and C. membranifaciens. Although largely susceptible to fluconazole, C. albicans, C. dubliniensis, C. humicola and C. sake demonstrated an emerging resistance with intermediate to total resistance observed in all the other species except for C. magnolia and C. globosa which were both susceptible to fluconazole. Conclusion: Early recognition and treatment of rare or resistant Candida species which may be contributing to patient morbidity and mortality in Libya is imperative

Carbapenem resistance expressed by Gram-negative bacilli isolated from a cohort of Libyan patients

Background and objectives: Carbapenem-resistant Enterobacteriaceae (CRE) and other Gram-negative bacteria are among the most common pathogens responsible for both community and hospital acquired infection. The global spread of cephalosporinases in Enterobacteriaceae has led to the increased use of carbapenems resulting in the emergence and rapid spread of CRE. This has become an alarming public health concern, yet the condition in Libya remains unclear. The aim of this study was to obtain a better understanding of CRE strains prevalent in Libyan patients by investigating their phenotypic characteristics and antibiograms. Methods: Gram-negative bacterial species were collected from Misrata Central Hospital, Misrata Cancer Centre and Privet Pathology Laboratories. Clinical samples and swabs were obtained from hospitalised and non-hospitalised patients and from mechanical ventilation and suction machines. Patients who had received antibiotic therapy for at least three days prior to the study were excluded. The identification and characterization of the isolated species were achieved using the growth characteristics on MacConkey and blood agar, spot tests and API 20E or API 20NE biochemical testing systems. Screening for carbapenem resistance was performed using the disk diffusion method with carbapenem 10 μg and cephalosporin 30 μg disks and minimum inhibitory concentrations (MIC) determined using the Sensititre Gram-negative Xtra plate format (GNX2F). All strains demonstrating resistance or reduced susceptibility to one of the four carbapenems were subjected to carbapenememase activity detection using the RAPIDEC CARBA NP test, Modified Hodge test and carbapenem inactivation methods. Results: A total of one hundred and forty isolates representing fourteen bacterial species were isolated from 140 non-duplicated specimens. Clinical specimens included urine samples (96/140, 68.57%), sputum (15/140, 10.71%), surgical wound swabs (18/140, 12.85%), foot swabs from diabetes mellitus (DM) patients (6/140, 4.29%), ear swabs (3/140, 2.14%) and wound swabs (2/140, 1.43%). Thirty-four (24.29%) isolates demonstrated resistance to at least one of the four carbapenems with Klebsiella pneumoniae representing 73.53% (25 isolates) of all carbapenem resistant species, followed by 8.82% for Pseudomonas aeruginosa (3 isolates), 5.88% for both Proteus mirabilis (2 isolates) and Escherichia coli (2 isolates) and 2.94% for both Citrobacter koseri (1 isolate) and Rahnella aquatilis (1 isolate). The other isolates were either susceptible or cephalosporinase producers. Conclusion: This study has revealed the high rate of carbapenem resistance amongst Libyan patients and emphasizes the crucial need for accurate screening, identification and susceptibility testing to prevent further spread of nosocomial and community acquired resistance. This may be achieved through the establishment of antibiotic stewardship programmes along with firm infection control practices.National Research Foundation of South Africa; Libyan GovernmentWeb of Scienc

Rare fungal species isolated from Libyan diabetic patients

BACKGROUND AND OBJECTIVES: The emerging resistance of Candida species to antifungals routinely used to treat candidiasis in HIV patients and in patients with diabetes mellitus (DM) has resulted in the frequent isolation of non-albicans Candida species. This study aimed to establish the prevalence and fluconazole resistance profiles of yeasts other than commonly identified Candida species which may be found colonizing the oral mucosa of Libyan patients with DM. METHODS: Fungal species were isolated from the oral cavity of DM-positive patients attending a diabetes clinic in Misrata Diabetes Centre in Libya. This study included patients aged between 35 and 95 years and excluded subjects who had been on antifungal therapy within two weeks prior to sample collection. The identification of the isolated species was done by growing the isolates on selective and chromogenic media and by API ID 32C biochemical testing. Antimicrobial susceptibility testing of the isolates to the antifungal fluconazole was performed using disk diffusion. The study complied with the Declaration of Helsinki (2013). RESULTS: Forty-four rare fungal isolates representing ten fungal species were identified from the oral mucosa of 194 patients, with 28.6% of rare Candida species demonstrating resistance to fluconazole. Saprochaete capitata and Cryptococcus humicola isolates demonstrated high levels of resistance to fluconazole, with other yeast species showing lower resistance levels. CONCLUSION: The methodologies used in this study allowed for the accurate identification of rare fungal species. The API 32 ID system was found to be a better identification method when compared to chromogenic media, as some species could not be identified with the latter. This study emphasizes the importance of accurate species identification and antifungal surveillance in patients with underlying chronic diseases such as DM who have higher morbidity and mortality rates due to less known and resistant fungal infections.Libyan Governmen