Evaluation of Usefulness of Polymerase Chain Reaction in the Diagnosis of Malaria in Nigeria

Microscopy has been the most common technique for the diagnosis of malaria in south western Nigeria. This study was undertaken to determine the efficiency of PCR for malaria diagnosis in south western Nigeria. A total of 450 samples submitted for malaria diagnosis at Obafemi Awolowo University Teaching Hospital Complex (OAUTHC), Ile-Ife between the months of January and December, 2009 were used. Methods used included Giemsa staining procedure for estimation of parasite densities and polymerase chain reaction (PCR) to detect the presence of malaria parasite in the whole blood. Using microscopy as reference gold standard, patients comprising 120 males and 330 females with age ranging between less than 1 and 60 samples were used. In all, about 255 (56.7 %) of the samples were positive for microscopy, while 75 (16.7 %) with high parasitaemia on microscopy were positive for PCR analysis. The study concluded that PCR for diagnosis of malaria has sensitivity of 29.4% and specificity of 100% using crude method of DNA extraction while the use of DNA extraction kit has sensitivity of 90.2% and specificity of 100%, hence effort should be geared towards increasing the sensitivity and reduce the cost of doing the test in low resource country like Nigeria

In-Vitro efficacy of antimicrobial agents used in the treatment of bacterial eye infections in Ibadan, Nigeria

Failure to cure eye infections, and reduced potency in topical antimicrobials had been observed in South Western Nigeria, this study sought to evaluate in vitro, the efficacy of antimicrobial agents in the treatment of ocular infections. A total of 46 ocular bacterial isolates were recovered from the diagnostic laboratory of the University College Hospital, Ibadan, from conjunctival swabs of patients having underlying eye diseases (Cataracts, glaucoma and esotrapia), and from patients presenting with other symptoms of eye infections. The pathogens incriminated were Staphylococcus aureus (73.5%), Coagulase negative Staphylococci (13.3%), Klebsiella species (10.3%), and Pseudomonas aeruginosa (2.0%). Disc diffusion tests (Bauer-Kirby method) were carried out using ciprofloxacin, gentamicin, chloramphenicol, erythromycin, augmentin, cefuroxime and levofloxacin. Broth dilution techniques were thereafter performed using gentamicin, chloramphenicol and ciprofloxacin. The microlide- erythromycin was 63.0% efficacious, augmentin and cefuroxime showed 71.1% and 76% efficacy. Minimum inhibitory concentrations (MIC) of commonly used topical antibiotics however showed different levels of resistance. Resistance to the aminoglycosides was marked, yielding 53.4% with MIC50= 8, MIC90 > 256, Resistance to chloramphenicol was even more marked 69.6% with MIC50= 16, MIC90= 64, the fluoroquinolones showed high efficacy- levofloxacin and ciprofloxacin showed 93.4% and 82.6% susceptibility respectively with MIC50 < 0.5, though slightly demonstrable resistance was observed (MIC90= 8). The study thus recommends the discontinuation of empirical therapy by physicians in order to stem the tide of resistance; it justifies the inclusion of the fluoroquinolones in susceptibility testing of ocular bacterial isolates, and its first line of choice if cure is warranted.doi: 10.4314/ajcem.v12i3.

In vitro resistance of gram-negative enteric bacilli from wound infections to honey

Letter to the Edito

Proteomic Analysis of Growth Phase-Dependent Expression of Legionella pneumophila Proteins Which Involves Regulation of Bacterial Virulence Traits

Legionella pneumophila, which is a causative pathogen of Legionnaires' disease, expresses its virulent traits in response to growth conditions. In particular, it is known to become virulent at a post-exponential phase in vitro culture. In this study, we performed a proteomic analysis of differences in expression between the exponential phase and post-exponential phase to identify candidates associated with L. pneumophila virulence using 2-Dimentional Fluorescence Difference Gel Electrophoresis (2D-DIGE) combined with Matrix-Assisted Laser Desorption/Ionization–Mass Spectrometry (MALDI-TOF-MS). Of 68 identified proteins that significantly differed in expression between the two growth phases, 64 were up-regulated at a post-exponential phase. The up-regulated proteins included enzymes related to glycolysis, ketone body biogenesis and poly-3-hydroxybutyrate (PHB) biogenesis, suggesting that L. pneumophila may utilize sugars and lipids as energy sources, when amino acids become scarce. Proteins related to motility (flagella components and twitching motility-associated proteins) were also up-regulated, predicting that they enhance infectivity of the bacteria in host cells under certain conditions. Furthermore, 9 up-regulated proteins of unknown function were found. Two of them were identified as novel bacterial factors associated with hemolysis of sheep red blood cells (SRBCs). Another 2 were found to be translocated into macrophages via the Icm/Dot type IV secretion apparatus as effector candidates in a reporter assay with Bordetella pertussis adenylate cyclase. The study will be helpful for virulent analysis of L. pneumophila from the viewpoint of physiological or metabolic modulation dependent on growth phase

The Mycobacterium tuberculosis homologue of the Mycobacterium avium mig gene is not specifically expressed in the macrophage

With the completion of genome sequencing of Mycobacterium tuberculosis and upsurge in the incidence of M. tuberculosis infection worldwide partly as a result of HIV pandemic, there is need for rationale approach to vaccine and chemotherapy discoveries for M. tuberculosis. The homologue of mig gene of Mycobacterium avium was searched for in the M. tuberculosis database at The Institute of Genomic Research (TIGR), USA and The Sanger Institute, UK. Homologue of the gene was found and comprehensively analysed. Reverse transcription PCR (RT-PCR) was carried out on the mig (fadD19) gene homologue and echA19 gene. The result of the RT-PCR showed that the mig gene was at least 2-fold upregulated during intracellular infection of macrophage compared to the broth grown bacilli as opposed to the demonstrated specific expression of mig gene in M. avium infected macrophage. The echA19 gene was also found to be upregulated. . © Ibadan Biomedical Communications Group

High levels of multidrug resistance in clinical isolates of Gram-negative pathogens from Nigeria.

International audienceIn Nigeria, quinolones and β-lactam antibiotics are widely used to treat bacterial infections. This study aimed to identify the prevalence of resistance to these drugs and to determine the mechanisms of resistance to these agents. In total, 134 non-duplicate, Gram-negative enteric isolates of 13 species from different hospitals were investigated for susceptibility to a panel of antibiotics, carriage of plasmid-mediated quinolone and β-lactam resistance genes, production of extended-spectrum β-lactamases (ESBLs), and mutations within topoisomerase genes. The level of resistance to all antibiotics tested was extremely high, with minimum inhibitory concentrations for 90% of the organisms (MIC values) of ≥256μg/mL for all drugs. Of the 134 isolates, 92 had mutations within the quinolone resistance-determining region (QRDR) of or within and . In addition, the plasmid-mediated quinolone resistance genes , , and were identified. The allele, which has previously only been found in isolates from China, was identified in two isolates and one isolate. Of the 134 isolates, 23 (17.2%) carried , 11 (8.2%) carried a variant and 5 (3.7%) were positive for . Twenty-eight isolates (20.9%) produced ESBL variants, with a CTX-M variant being carried by 25 isolates (18.7%). In addition, six isolates (4.5%) carried variants [ACT-1 (1 isolate), DHA-1 (4 isolates) and CMY-2 (1 isolate)]. This study demonstrates a very high level of multidrug resistance amongst Gram-negative enteric bacilli isolated from different sites from patients in Nigerian hospitals as well as the presence of a variety of plasmid-associated resistance genes, including some identified from Africa for the first time

Co-agulase Negative Staphylococcus Distribution in Clinical Sample in a Tertiary Hospital in Ibadan, Nigeria

Numerous researchers have described the isolation of coagulase-negative staphylococci especially S. epidermidis, and the association of the bacteria with clinical disease. In this study we determined the distribution of coagulase-negative staphylococci isolated from clinical samples in tertiary hospital. One hundred and fifteen repeat CoNS isolates were obtained from 607 various clinical specimens using standard precedures; 97 (84.3%) were strains of S. epidermidis while 18 (15.7%) were S. Saprophyticus. The highest number of isolates of CoNS were from Blood culture, 75 out of 115 strains (65.2%) and 68.0% were strains of S. epidermidis. Septicaemia had the highest prevalence of CoNS, 31.4%; followed by endocraditis, 25.0%. The least was found in otits and pyrexia of unkonwn origin, 7.4% and 8.3% respectively. All the CoNS strains were resistant to one or more of the eleven antimicrobial agents used. The frequancy of susceptibility to fluoroquinolones was the highest; ofloxacin(81.7%), ciprofloxacin (77.4%). The least susceptibility was found in tetracycline; 20.0%. No isolate was sensitive to cotrimoxazole. However, S. epidermidis had a greater percentage of strains susceptibleto the quinolones; ofloxacin; 84.0% and ciprofloxacin; 80.0% than the S. saprohyticus, ofloxacin; 67.0% and ciprofloxacin; 44.0%. The distribution of CoNS in clinical specimens obtained from hospital enivronment in this study has shown that CoNS have become an important pathogen, therefore antimicrobial susceptibility tests should be carried out as a guide for therapy and to control development of resistant strains

From curiosity to commodity: a review of the evolution of sachet drinking water in West Africa

The private sector continues to play an important role in filling local drinking water supply gaps across the Global South. In West Africa, a perfect storm of rapid population growth, infrastructure mismanagement, and globalization of consumer markets has resulted in the advent of an entire new industry around packaged water, primarily ‘sachet water’ sold in mechanically sealed plastic sleeves. Most local governments and international development agencies have historically perceived sachet water as a passing trend, but it has quickly become a primary drinking water source for the majority of households in many urban areas and continues to spread throughout the region and world. Sachet water is now an important component of regional water security, although with attendant issues related to governance, quality control, environmental pollution, and social justice. This paper reviews the seminal literature on sachet water in West Africa, with particular emphasis on Ghana and Nigeria, where most studies have focused. This review synthesizes governance issues, consumer and industry trends, and the latest on product quality in the literature from 2011 to 2016, with 2010 approximating an inflection point for the modernization of the industry. The ability of many West African nations to achieve universal access to safe drinking water may depend on their willingness to understand and incorporate the sachet water industry into an integrated drinking water platform. WIREs Water 2017, 4:e1206. doi: 10.1002/wat2.1206 This article is categorized under: Engineering Water > Planning Water Engineering Water > Sustainable Engineering of Water Human Water > Water Governance A typical 500‐mL sachet of drinking water sold in Accra, Ghana