Cryptococcosis in Africa: What the data tell us.

Cryptococcosis is a neglected tropical disease and the main cause of fungal-related deaths in HIV-positive persons in Africa. It is an AIDS-defining illness that has almost surpassed tuberculosis (TB) in mortality despite wide coverage with antiretroviral therapy. What is known about the cryptococcosis burden in Africa is from estimations based on data from a few studies on the infection burden and associated complications. Consequently, the projected implications of cryptococcosis in Africa have been based on these estimations. This systematic review is aimed at providing unique and up-to-date data on the burden of cryptococcosis in Africa using published hospital-based research data on cryptococcosis in HIV infected and uninfected persons. The review also focused on providing temporal data on the availability of diagnostic and therapeutic options for cryptococcosis in Africa. From our results, about 40 948 cases of cryptococcosis were reported in Africa from 1969 to 2021, and the highest prevalence of cryptococcosis was from southern Africa. The most isolated species was Cryptococcus neoformans 42.4% (17 710/41 801) and only 1.3% (549/41 801) isolates were C. gattii. C. neoformans (serotype A) VN I 64.5% (918/1522) was the most prevalent serotype in Africa, while C. gattii (serotype C) VG IV was thought to pose a huge danger. However, C. neoformans (serotype A) VN I continued to be the major threat in Africa. Due to the limited availability of molecular typing methods and the widespread use of culture, direct microscopy, and serological techniques for diagnosis, 23 542 isolates were uncharacterised. Amphotericin B and flucytosine combination therapy is highly recommended for treatment of cryptococcal meningitis. However, these drugs are expensive and remain largely unavailable in most African countries. Amphotericin B requires laboratory facilities to monitor for toxicity. Although fluconazole monotherapy is the readily available treatment option for cryptococcosis, drug resistance, and high mortality have been recorded in majority of cases in Africa. The lack of awareness and paucity of published data on cryptococcosis are likely to have contributed to the underestimation of cases in Africa and led to underprioritisation of this important disease.

Cryptococcosis is a neglected tropical disease that manifests greatly in immunocompromised persons especially those with HIV infection. Our data show that managing cryptococcosis will require an integrated multidisciplinary approach that should include the utilisation of cryptococcal antigen (CrAg) testing, which is highly sensitive and cost-effective for diagnosing this disease.

Antimicrobial Peptides Therapy: An Emerging Alternative for Treating Drug-Resistant Bacteria.

Microbial resistance to antibiotics is an ancient and dynamic issue that has brought a situation reminiscent of the pre-antibiotic era to the limelight. Currently, antibiotic resistance and the associated infections are widespread and pose significant global health and economic burden. Thus, the misuse of antibiotics, which has increased resistance, has necessitated the search for alternative therapeutic agents for combating resistant pathogens. Antimicrobial peptides (AMPs) hold promise as a viable therapeutic approach against drug-resistant pathogens. AMPs are oligopeptides with low molecular weight. They have broad-spectrum antimicrobial activities against pathogenic microorganisms. AMPs are nonspecific and target components of microbes that facilitate immune response by acting as the first-line defense mechanisms against invading pathogenic microbes. The diversity and potency of AMPs make them good candidates for alternative use. They could be used alone or in combination with several other biomaterials for improved therapeutic activity. They can also be employed in vaccine production targeting drug-resistant pathogens. This review covers the opportunities and advances in AMP discovery and development targeting antimicrobial resistance (AMR) bacteria. Briefly, it presents an overview of the global burden of the antimicrobial resistance crisis, portraying the global magnitude, challenges, and consequences. After that, it critically and comprehensively evaluates the potential roles of AMPs in addressing the AMR crisis, highlighting the major potentials and prospects.

Invasive candidiasis in Africa, what is the current picture?

Invasive candidiasis is a serious, progressive, and potentially deadly infection that can affect the brain, heart, bones, eyes, and other parts of the body. It is associated with risk factors such as the use of indwelling medical devices, prolonged hospital stay, and broad-spectrum antibiotics use. It is especially seen in immunocompromised individuals such as patients with prolonged hospital stay, gastrointestinal surgery, haematological malignancies, and respiratory diseases. We have conducted a systematic search of literature using a select group of databases and appropriate search words and found that in Africa, there are 18 293 documented/reported cases of invasive candidiasis in the last few decades (1976-2021) and 16 636(91%) were cases of candidaemia. South Africa had the highest number of reported cases-15 002(82%), which may be due to underreporting of cases in other countries. HIV positive persons with invasive candidiasis in Africa accounted for 1 052(5.8%). Candida albicans was the most frequently isolated species 6 328(32.6%), followed by Candida parapsilosis 5 910(30.4%), and Candida auris 1 505(7.8%). Due to the affordability and availability of blood culture, it was used for diagnosis in most of the studies examined, while a few studies combined other techniques and just three studies from two countries used serological tests. Echinocandins are recommended as first-line therapy but are only available in 12 countries and are highly priced. The use of fluconazole, because of its availability and relatively inexpensive nature, has led to increased resistance of Candida species to the drug.

Genome plasticity in Candida albicans: A cutting-edge strategy for evolution, adaptation, and survival.

Candida albicans is the most implicated fungal species that grows as a commensal or opportunistic pathogen in the human host. It is associated with many life-threatening infections, especially in immunocompromised persons. The genome of Candida albicans is very flexible and can withstand a wide assortment of variations in a continuously changing environment. Thus, genome plasticity is central to its adaptation and has long been of considerable interest. C. albicans has a diploid heterozygous genome that is highly dynamic and can display variation from small to large scale chromosomal rearrangement and aneuploidy, which have implications in drug resistance, virulence, and pathogenicity. This review presents an up-to-date overview of recent genomic studies involving C. albicans. It discusses the accumulating evidence that shows how mitotic recombination events, ploidy dynamics, aneuploidy, and loss of heterozygosity (LOH) influence evolution, adaptation, and survival in C. albicans. Understanding the factors that affect the genome is crucial for a proper understanding of species and rapid development and adjustment of therapeutic strategies to mitigate their spread.

Multi-locus sequence typing reveals genotypic similarity in Nigerian Cryptococcus neoformans AFLP1/VNI of environmental and clinical origin.

IntroductionPigeon droppings are among the major environmental sources of Cryptococcus neoformans AFLP1/VNI, from where the organism infects susceptible humans and animals resulting in cryptococcosis. Until now, C. neoformans AFLP1B/VNII was the only molecular type reported in Nigeria. Effective clinical treatment of this infection has occasionally been stymied by the emergence of antifungal non-susceptible, and resistant strains of C. neoformans AFLP1/VNI.Hypothesis/Gap StatementPigeon droppings harbour C. neoformans and HIV/AIDS patients are among the susceptible population to develop cryptococcal infection. Epidemiological data on cryptococcal prevalence is limited in Nigeria.AimTo investigate the environmental prevalence of C. neoformans in South-eastern Nigeria and compare the isolates with other lineages by using molecular and microbiological tools.MethodologyA total of 500 pigeon droppings and 300 blood samples of HIV/AIDS patients were collected, respectively, from five market squares and three tertiary healthcare centres within the Nsukka area of South-eastern Nigeria. The antifungal susceptibility of the C. neoformans isolates to amphotericin B, fluconazole, 5-fluorocytosine, itraconazole, voriconazole, posaconazole, and isavuconazole was investigated based on the CLSI M27-A3 protocol. Yeasts were identified by MALDI-TOF MS, thereafter Cryptococcus MLST was performed according to the International Society for Human and Animal Mycology (ISHAM) consensus scheme.Results C. neoformans was recovered from 6 (1.2 %) pigeon droppings and 6 (2 %) blood cultures of HIV/AIDS patients. Molecular analyses indicated that all cryptococcal isolates belong to serotype A and the AFLP1/VNI molecular type with sequence type (ST)32. Infection with C. neoformans was independent of sex and age of the patients investigated. All C. neoformans isolates were susceptible to the seven antifungal agents.ConclusionThis is the first report on the prevalence of C. neoformans AFLP1/VNI (ST32) in environmental and clinical samples from Nigeria. The antifungal susceptibility indicates that antifungal resistance by C. neoformans is yet a rare occurrence in Nigeria.

Nanoparticles as therapeutic options for treating multidrug-resistant bacteria: research progress, challenges, and prospects.

Resistance to antimicrobial agents has been alarming in recent years and poses a huge public health threat globally according to the WHO. The increase in morbidity and mortality resulting from microbial infections has been attributed to the emergence of multidrug-resistant microbes. Associated with the increase in multidrug resistance is the lack of new and effective antimicrobials. This has led to global initiatives to identify novel and more effective antimicrobial agents in addition to discovering novel and effective drug delivery and targeting methods. The use of nanoparticles as novel biomaterials to fully achieve this feat is currently gaining global attention. Nanoparticles could become an indispensable viable therapeutic option for treating drug-resistant infections. Of all the nanoparticles, the metals and metal oxide nanoparticles appear to offer the most promise and have attracted tremendous interest from many researchers. Moreover, the use of nanomaterials in photothermal therapy has received considerable attention over the years. This review provides current insight on antimicrobial resistance as well as the mechanisms of nanoparticle antibacterial activity. It offers an in-depth review of all the recent findings in the use of nanomaterials as agents against multi-resistant pathogenic bacteria. Also, nanomaterials that can respond to light stimuli (photothermal therapy) to kill microbes and facilitate enhanced drug delivery and release are discussed. Moreover, the synergistic interactions of nanoparticles with antibiotics and other nanomaterials, microbial adaptation strategies to nanoparticles, current challenges, and future prospects were extensively discussed.

Epidemiology of Cryptococcus and cryptococcosis in Western Africa.

Cryptococcosis is a serious and sometimes fatal fungal disease caused by Cryptococcus species. Worldwide, it is estimated to kill over 180 000 annually, with 75% of deaths occurring in sub-Saharan Africa. Though cryptococcal infections are rare in otherwise healthy individuals, there have been reported cases in immunocompetent persons. Most cases occur in individuals who have weakened immune systems, particularly those with advanced HIV/AIDS, thus making West Africa a potential hotspot of the disease. Despite this, there is no recent review article with a focus on published findings on cryptococcosis in Western Africa. Common clinical symptoms include chest pain, dry cough, headache, nausea, confusion, fever, fatigue and stiffness of the neck/neurological impairment. The CNS and the lung remain its preferred target even though rare cases of attack on other parts of the body were reported in this review. Cryptococcal antigen screening and India ink preparation were the most commonly used diagnostic methods. Repeated isolation from environmental samples was observed. Overall, data on the clinical prevalence of Cryptococcus are scarce and variable in the region. The environmental prevalence ranges from 2.3% to 22%. This review covers all published research findings on cryptococcosis in West Africa till date. The epidemiological data will likely be of interest to clinicians within and outside the continent. The nations covered in this review include the following: Benin Republic, Burkina Faso, Cote d'ivoire, Ghana, Guinea, Guinea- Bissau, Mali, Nigeria, Senegal and Sierra Leone. More studies are warranted to fill the observed gaps on the epidemiology of Cryptococcus in the region.

The persistence of amoebosis caused by Entamoeba histolytica in Nigeria and the role of malnutrition.

Amoebosis, caused by the protozoan parasite Entamoeba histolytica is a gastrointestinal infection and the second leading cause of death from parasitic disease worldwide. The disease is endemic in many developing countries and kills over one hundred thousand persons annually. Adequate nutrition composed of macro- and micronutrients in their balanced proportions is central to effective gut immune response and the homeostasis of commensal organisms in the gastrointestinal tract. Entamoeba histolytica is a gut pathobiont that can exploit a shift in nutritional status to cause amoebosis, with extra-intestinal complications. Although undernutrition is rarely a public health concern in high income settings, bioavailability of functional nutrients remains suboptimal. On the other hand, nutrient deficiencies constitute a chronic challenge in very low-income regions. This study sought to review the pivotal influence of malnutrition on intact microbiota and functional immunity, as determinants of susceptibility to amoebosis in the Nigerian example of tropical regions. The dynamics of the infection such as possible coinfection with opportunistic pathogens were also, evaluated. Based on the available reports, we posit that amoebosis is a common tropical infection perpetuated by malnutrition following poor living standard including unhygienic environmental exposure.

The use of nanoparticles as alternative therapeutic agents against Candida infections: an up-to-date overview and future perspectives.

Candida spp. are opportunistic fungi that can cause severe infections especially in immunocompromised patients. Candidiasis is currently the most frequent fungal disease affecting humans globally. This rise is attributed to the vast increase in resistance to antifungal agents. In recent years, the epidemiological and clinical relevance of fungal infections caused by Candida species have attracted a lot of interest with increasing reports of intrinsic and acquired resistance among Candida species. Thus, the formulation of novel, and efficient therapy for Candida infection persists as a critical challenge in modern medicine. The use of nanoparticle as a potential biomaterial to achieve this feat has gained global attention. Nanoparticles have shown promising antifungal activity, and thus, could be seen as the next generation antifungal agents. This review concisely discussed Candida infection with emphasis on anti-candida resistance mechanisms and the use of nanoparticles as potential therapeutic agents against Candida species. Moreover, the mechanisms of activity of nanoparticles against Candida species, recent findings on the anti-candida potentials of nanoparticles and future perspectives are also presented.

Mechanism of Candida pathogenesis: revisiting the vital drivers.

Candida is the most implicated fungal pathogen in the clinical setting. Several factors play important roles in the pathogenesis of Candida spp. Multiple transcriptional circuits, morphological and phenotypic switching, biofilm formation, tissue damaging extracellular hydrolytic enzymes, metabolic flexibility, genome plasticity, adaptation to environmental pH fluctuation, robust nutrient acquisition system, adherence and invasions (mediated by adhesins and invasins), heat shock proteins (HSPs), cytolytic proteins, escape from phagocytosis, evasion from host immune system, synergistic coaggregation with resident microbiota, resistance to antifungal agents, and the ability to efficiently respond to multiple stresses are some of the major pathogenic determinants of Candida species. The existence of multiple connections, in addition to the interactions and associations among all of these factors, are distinctive features that play important roles in the establishment of Candida infections. This review describes all the underlying factors and mechanisms involved in Candida pathogenesis by evaluating pathogenic determinants of Candida species. It reinforces the already available pool of data on the pathogenesis of Candida species by providing a clear and simplified understanding of the most important factors implicated in the pathogenesis of Candida species. The Candida pathogenesis network, an illustration linking all the major determinants of Candida pathogenesis, is also presented. Taken together, they will further improve our current understanding of how these factors modulate virulence and consequent infection(s). Development of new antifungal drugs and better therapeutic approaches to candidiasis can be achieved in the near future with continuing progress in the understanding of the mechanisms of Candida pathogenesis.

Nutrition, malnutrition, and leishmaniasis.

Leishmaniasis is a vector-borne infectious disease with a long history of infecting humans and other animals. It is a known emerging or resurging disease. The host nutritional state has an indispensable role in defense against pathogens. The host defense system disorganization as a result of undernutrition is responsible for asymptomatic infections and even severe diseases. Host susceptibility and pathophysiologic severity to infection can be aggravated owing to undernourishment in a number of pathways, and infection also may aggravate preexisting poor nutrition or further increase host susceptibility. This study suggests that there may be some relationship between malnutrition and the endemicity of the parasite. The susceptibility to and severity of leishmanial infection can be altered by the body weight and serum levels of micronutrients. Nutrition not only affects the vulnerability of the host but also may affect the desire of sandfly to bite a specific host. Apart from host defense mechanism, nutritional stress also greatly influences vector competence and host-seeking behavior, especially during larvae development. The host and sandfly vector nutritional states could also influence the evolution of the parasite. It is essential to elucidate the roles that diets and nutrition play in the leishmanial life cycle. The aim of this article is to review the influences of nutrition and diets on the host susceptibility and severity of infection, preemptive and therapeutic strategy feedback, parasite evolution, and vector competence.

Evaluation of physicochemical and antioxidant properties of two stingless bee honeys: a comparison with Apis mellifera honey from Nsukka, Nigeria.

OBJECTIVE: Several physical, biochemical and antioxidant properties of two Nigerian stingless bee honey varieties (Melipona sp. and Hypotrigona sp.) were compared with Apis mellifera honey using standard analytical procedures. RESULTS: The mean pH of Apis mellifera, Hypotrigona sp. and Melipona sp. honeys were 4.24 ± 0.28, 3.75 ± 0.11 and 4.21 ± 0.37 respectively. The mean moisture contents of the honeys were 11.74 ± 0.47, 17.50 ± 0.80, and 13.86 ± 1.06%. Honey samples from Hypotrigona sp. when compared with other honey samples had the highest mean total dissolved solids (370.01 ± 22.51 ppm), hydroxymethylfurfural (16.58 ± 0.37 mg/kg), total acidity (35.57 ± 0.42 meq/kg), protein content (16.58 ± 0.37 g/kg), phenol content (527.41 ± 3.60 mg/kg), and ascorbic acid (161.69 ± 6.70 mg/kg), antioxidant equivalent-ascorbic acid assay value (342.33 ± 0.78 mg/kg) as well as ferric reducing power (666.88 ± 1.73 µM Fe(II)/100 g) (p < 0.05). Several strong correlations were observed among some of the parameters of the honeys. This is the first study to compare the properties of Nigerian honey bees. Our results suggested that these honeys (specifically Hypotrigona sp. honey) is a good source of antioxidants comparable to A. mellifera honey.

Human papillomavirus oncogenic E6 protein regulates human ß-defensin 3 (hBD3) expression via the tumor suppressor protein p53.

Human ß-defensin-3 (hBD3) is an epithelial cell-derived innate immune regulatory molecule overexpressed in oral dysplastic lesions and fosters a tumor-promoting microenvironment. Expression of hBD3 is induced by the epidermal growth factor receptor signaling pathway. Here we describe a novel pathway through which the high-risk human papillomavirus type-16 (HPV-16) oncoprotein E6 induces hBD3 expression in mucosal keratinocytes. Ablation of E6 by siRNA induces the tumor suppressor p53 and diminishes hBD3 in HPV-16 positive CaSki cervical cancer cells and UM-SCC-104 head and neck cancer cells. Malignant cells in HPV-16-associated oropharyngeal cancer overexpress hBD3. HPV-16 E6 induces hBD3 mRNA expression, peptide production and gene promoter activity in mucosal keratinocytes. Reduction of cellular levels of p53 stimulates hBD3 expression, while activation of p53 by doxorubicin inhibits its expression in primary oral keratinocytes and CaSki cells, suggesting that p53 represses hBD3 expression. A p53 binding site in the hBD3 gene promoter has been identified by using electrophoretic mobility shift assays and chromatin immunoprecipitation (ChIP). In addition, the p63 protein isoform ΔNp63α, but not TAp63, stimulated transactivation of the hBD3 gene and was co-expressed with hBD3 in head and neck cancer specimens. Therefore, high-risk HPV E6 oncoproteins may stimulate hBD3 expression in tumor cells to facilitate tumorigenesis of HPV-associated head and neck cancer.

ISOLATION OF Cryptococcus neoformans FROM ENVIRONMENTAL SAMPLES COLLECTED IN SOUTHEASTERN NIGERIA.

Cryptococcosis caused by Cryptococcus neoformans is the second most common fungal opportunistic pathogen and a life-threatening infection with serious clinical manifestations especially in HIV/AIDS and other immunocompromised patients. In Nigeria, HIV/AIDS infection has reached an alarming level. Despite this, information on the presence of this fungus in clinical and environmental samples is very scanty in Nigeria and many other parts of Africa. We set out to evaluate the presence of Cryptococcus neoformans or C. gattiiin pigeon droppings obtained from Southeastern Nigeria. One hundred and seventy-seven samples of pigeon droppings from six sample types were collected. The area covered comprised of ten cities and other locations spanning across five States in Nigeria. Using established techniques, Cryptococcus neoformans was isolated from 39 of the 177 (22.0%) samples overall. No C. gattiiwas isolated. Most of the isolates (32.4%) were recovered from dovecotes (11 of 34) followed closely by samples taken from markets (31.8%; seven of 22) and least from the church (4.0%; one of 25). The highest isolation rate (38.9%) was found in samples from Enugu-Ezike(seven of 23) while the least came from Afikpo and the other locations each with 9.1% isolation rate. This is the first large-scale screening of Cryptococcus neoformans from pigeon droppings in Nigeria. The ecological and epidemiological significance of these findings are discussed.

Isolation of cryptococcus neoformans from environmental samples collected in Southeastern Nigeria / Isolamento de Cryptococcus neoformans de amostras ambientais coletadas no sudeste da Nigéria

SUMMARYCryptococcosis caused by Cryptococcus neoformansis the second most common fungal opportunistic pathogen and a lifethreatening infection with serious clinical manifestations especially in HIV/AIDS and other immunocompromised patients. In Nigeria, HIV/AIDS infection has reached an alarming level. Despite this, information on the presence of this fungus in clinical and environmental samples is very scanty in Nigeria and many other parts of Africa. We set out to evaluate the presence of Cryptococcus neoformansor C. gattiiin pigeon droppings obtained from Southeastern Nigeria. One hundred and seventy-seven samples of pigeon droppings from six sample types were collected. The area covered comprised of ten cities and other locations spanning across five States in Nigeria. Using established techniques, Cryptococcus neoformanswas isolated from 39 of the 177 (22.0%) samples overall. No C. gattiiwas isolated. Most of the isolates (32.4%) were recovered from dovecotes (11 of 34) followed closely by samples taken from markets (31.8%; seven of 22) and least from the church (4.0%; one of 25). The highest isolation rate (38.9%) was found in samples from Enugu-Ezike(seven of 23) while the least came from Afikpoand the other locations each with 9.1% isolation rate. This is the first large-scale screening of Cryptococcus neoformansfrom pigeon droppings in Nigeria. The ecological and epidemiological significance of these findings are discussed.

RESUMOA criptococose, causada por Cryptococcus neoformans, é o segundo patógeno fúngico oportunista mais comum em infecções com risco de vida e manifestações clínicas graves, especialmente em HIV/AIDS e outros pacientes imunocomprometidos. Na Nigéria, a infecção pelo HIV/AIDS atingiu um nível alarmante. Apesar disso, informações sobre a presença desses fungos em amostras clínicas e ambientais é muito escassa na Nigéria e em muitas outras partes da África. Propusemo-nos a avaliar a presença de Cryptococcus neoformansou C. gattiiem fezes de pombos obtidos do sudeste da Nigéria. Foram coletadas 177 amostras de fezes de pombos de seis localidades. A área coberta foi composta por dez cidades e outras localidades abrangendo cinco Estados na Nigéria. Usando técnicas estabelecidas, Cryptococcus neoformansfoi isolado de 39 do total de 177 (22,0%) amostras. Nenhuma amostra de C. gattiifoi isolada. A maioria dos isolados (32,4%) foi recuperada de pombais (11 de 34), seguido de perto por amostras colhidas em mercados (31,8%; 7 de 22) e por último na igreja (4,0%; 1 de 25). A maior taxa de isolamento (38,9%) foi encontrada em amostras de Enugu-Ezike (7 de 23), enquanto a menor taxa foi de Afikpo e os outros locais, cada um deles com taxa de isolamento de 9,1%. Esta é a primeira triagem em larga escala de Cryptococcus neoformansem fezes de pombos na Nigéria. A importância ecológica e epidemiológica destes achados é discutida.

Frequency, urinalysis and susceptibility profile of pathogens causing urinary tract infections in Enugu State, southeast Nigeria.

OBJECTIVE: This study was designed to determine the frequency and causative agent(s) of urinary tract infections (UTIs) in individuals with symptoms of urinary tract infections in Enugu State of Southeast Nigeria, and to determine the antibiotic susceptibility pattern of microbial agents isolated from urine culture. METHODS: The study involved 211 individuals (149 females and 62 males) clinically suspected for UTI. Urine samples were collected by the mid-stream 'clean catch' method and tested using standard procedures. Antibiotic susceptibility of the isolated pathogens was tested using the Kirby-Bauer technique according to the Clinical and Laboratory Standards Institute (CLSI) guidelines. RESULTS: Microscopy of centrifuged urine samples showed 16 patients had pyuria while 54 had pus cells. Calcium oxalate crystals were found in 14 samples. Urinalysis performed with urine samples showed 17 had protein; seven were nitrite positive and three had moderate to high glucose concentration. Fifty-four urine samples (36.2%) from females and 12 (19.4%) from males showed significant growth upon culture. Gram stain and biochemical tests identified nine different organisms with Escherichia coli as the most common isolated species. Forty three randomly selected strains were further tested for their susceptibility against a panel of antibiotics. Thirty isolates (81.08%) were resistant to four or more antibiotics with the highest resistance shown by E. coli (76.67%). All the Gram- negative isolates were resistant to Ampicilox, Cefuroxime and Amoxicillin. CONCLUSION: Urinary tract infections were found more in females in the area under study. As found in other studies, E. coli was the most predominant isolate, although other organisms seem to be on the increase.

Frequency, urinllysis and susceptibility profil of pathogens causing urinary ttract infections in enugu state, southeast Nigeria / Perfil da frequencia, analise urinaria e suscetibilidade de patogenos causando infeccoes do trato urinario no estado de Enugu, Sudeste da Nigeria

Objective: This study was designed to determine the frequency and causative agent(s) of urinary tract infections (UTIs) in individuals with symptoms of urinary tract infections in Enugu State of Southeast Nigeria, and to determine the antibiotic susceptibility pattern of microbial agents isolated from urine culture. Methods: The study involved 211 individuals (149 females and 62 males) clinically suspected for UTI. Urine samples were collected by the mid-stream ‘clean catch' method and tested using standard procedures. Antibiotic susceptibility of the isolated pathogens was tested using the Kirby-Bauer technique according to the Clinical and Laboratory Standards Institute (CLSI) guidelines. Results: Microscopy of centrifuged urine samples showed 16 patients had pyuria while 54 had pus cells. Calcium oxalate crystals were found in 14 samples. Urinalysis performed with urine samples showed 17 had protein; seven were nitrite positive and three had moderate to high glucose concentration. Fifty-four urine samples (36.2%) from females and 12 (19.4%) from males showed significant growth upon culture. Gram stain and biochemical tests identified nine different organisms with Escherichia coli as the most common isolated species. Forty three randomly selected strains were further tested for their susceptibility against a panel of antibiotics. Thirty isolates (81.08%) were resistant to four or more antibiotics with the highest resistance shown by E. coli (76.67%). All the Gram- negative isolates were resistant to Ampicilox, Cefuroxime and Amoxicillin. Conclusion: Urinary tract infections were found more in females in the area under study. As found in other studies, E. coli was the most predominant isolate, although other organisms seem to be on the increase.

Objetivo: O estudo teve como objetivo determinar a frequência e agentes causadores das infecções do trato urinário (UTIs) em indivíduos com sintomas desta infecção no estado de Enugu, Sudeste da Nigéria e determinar a suscetibilidade antibiótica dos agentes microbianos isolados de cultura da urina. Métodos: O estudo envolveu 211 indivíduos (149 mulheres e 62 homens) clinicamente suspeitos para UTI. Amostras urinárias foram coletadas pelo método de meia corrente “clean catch” e testados por procedimentos standards. Suscetibilidade aos antibióticos dos patógenos isolados foi testada usando a técnica de Kirby-Bauer e de acordo com as diretrizes do “Clinical and Laboratory Standards Institute” (CLSI). Resultados: Microscopia das amostras de urina centrifugadas mostraram que 16 pacientes tinham piúria enquanto que 54 tinham células do pus. Cristais de oxalato de cálcio foram encontrados em 14 amostras. Análise de amostras da urina mostraram que 17 tinham proteína; sete eram positivas para nitrito e três tinham concentração de glicose de moderada para alta. Cinquenta e quatro amostras de urina (36.2% de mulheres) e 12 (19.45% de homens) mostraram crescimento significante após cultura. Coloração pelo Gram e testes bioquímicos identificaram nove organismos diferentes com a Escherichia coli sendo a mais comum das espécies isoladas. Quarenta e três espécies selecionadas ao acaso foram testadas posteriormente para sua suscetibilidade contra um painel de antibióticos. Trinta amostras isoladas (81.08%) foram resistentes a quatro ou mais antibióticos sendo que a maior resistência foi da E. coli (76.67%). Todas as amostras Gram negativas isoladas foram resistentes a Ampicilox, Cefuroxime e Amoxicilina.

Comparative analysis of urinary schistosomiasis among primary school children and rural farmers in Obollo-Eke, Enugu State, Nigeria: implications for control.

OBJECTIVE: To determine the prevalence, sex-age related intensity of urinary schistosomiasis and to compare such parameters among rural school children and rural farmers in selected communities in Obollo-Eke located in Southeast, Nigeria. METHODS: A cross-sectional survey involving 1 337 school children and farmers was conducted in Obollo-Eke community between September 2006 and July 2007. Demographic data of subjects was collected using a questionnaire prepared for this purpose. Urine samples were collected and examined for haematuria and ova of Schistosoma haematobium (S. haematobium) using Medi-test Combi 9 and sedimentation technique respectively. RESULTS: The prevalence of urinary schistosomiasis based on microscopic examination of the urine sediment for the ova of S. haematobium was 17.5% while the prevalence of haematuria was 15.6%. Infection intensity varied from light to heavy. In general, the prevalence was higher among males (20.8%) than females (14.6%; P>0.05) and was slightly higher among primary school children (18.0%; n=762) than farmers (16.9%; n=575; P>0.05). The age-specific prevalence of schistosomiasis among the study subjects ranged from 8.3% to 21.2% in 0-5 years and 11-15 years age groups respectively. CONCLUSIONS: Haematuria and mean egg/10 mL urine (r = 0.95; P<0.01) showed that both procedures are reliable for the diagnosis of the disease and can be used to ascertain the prevalence of the disease in any community. The comparative analysis of urinary bilharziasis among primary school children and rural farmers demonstrated that the infection is moderately high in these two risk population groups at Obollo-Eke. A robust intervention strategy is clearly needed.

Development of a 96-well catheter-based microdilution method to test antifungal susceptibility of Candida biofilms.

BACKGROUND: Candida biofilms, which are often associated with device-related infections, including catheter-related bloodstream infections, are resistant to commonly used antifungal agents. Current microtitre (96-well) plate-based methods to determine the antifungal susceptibility of these biofilms do not involve clinically relevant substrates (e.g. catheters), and are not well suited for evaluating the surface topography and three-dimensional architecture of biofilms. We describe a simple, reproducible catheter-based microtitre plate method to form biofilms and evaluate their antifungal susceptibility. METHODS: Biofilms were formed by Candida species on 5 mm catheter discs placed in microtitre plates and quantified using metabolic conversion of a formazan dye (XTT). The morphology, surface topography and three-dimensional architecture of these biofilms were evaluated by fluorescence, confocal scanning laser and scanning electron microscopy, respectively. The optimized XTT method was used to evaluate the antifungal susceptibility of formed Candida biofilms to fluconazole, voriconazole, itraconazole and anidulafungin. RESULTS: Maximum XTT activity was achieved within 90 min. All tested Candida strains formed robust biofilms on catheter discs at both 24 and 48 h (P = 0.66). Biofilms exhibited typical gross morphology, surface topography and architecture, and no difference in biofilm thickness (P = 0.37). The three tested azoles were not active against the biofilms (MIC ≥ 64 mg/L), but anidulafungin possessed potent activity against them (MIC = 0.063-0.125 mg/L). CONCLUSIONS: The developed method is simple, rapid and reproducible, and requires relatively small amounts of drug. It can be used to perform both high-resolution microscopic analysis of the topography and architecture of biofilms, and evaluation of their antifungal susceptibility.

Dermatophytoses in domesticated animals.

Dermatophytes are among the most frequent causes of ringworm infections in domesticated animals. They are known to serve as reservoirs of the zoophilic dermatophytes and these infections have important zoonotic implication. In Nigeria and probably West Africa, there are not many studies on the incidence of dermatophytosis in domesticated animals. In the current study, 538 domesticated animals with clinically suggestive lesions were investigated for dermatophytes. Identification of dermatophyte species was performed by macro- and micro morphological examination of colonies and by biochemical methods. In the cases of isolates that had atypical morphology and/or biochemical test results, the rDNA internal transcribed spacer region 2 (ITS 2) sequencing was performed. Out of this number, 214 (39.8%) were found to be colonized by a variety of ten species of dermatophytes. M. canis was the most frequently isolated species (37.4%), followed by T. mentagrophytes (22.9%) and T. verrucosum (15.9%). M. persicolor and T. gallinae were jointly the least species isolated with a frequency of 0.55% respectively. The recovery of dermatophyte isolates previously shown to be common etiological agents of dermatophytosis especially from children in the same region suggests that animal to human transmission may be common. Possible implications and recommendations are discussed.