DSpace Angular :: Browsing by Author "Phillips, Richard Odame"

Browsing by Author "Phillips, Richard Odame"

Now showing 1 - 20 of 71

Antibody screening tests variably overestimate the prevalence of hepatitis C virus infection among HIV-infected adults in Ghana
(John Wiley & Sons Ltd, 2014) King, S.; Adjei-Asante, K.; Appiah, L.; Adinku, D.; Phillips, Richard Odame; et. al
HIV coinfection with HCV has been poorly studied in sub-Saharan Africa, and the reliability of available seroprevalence estimates remains uncertain. The study aim was to determine HCV RNA prevalence in HIV-infected subjects receiving care in Kumasi, Ghana, and relate the findings to HCV antibody detection. From a population of 1520 HIV-infected adults, all HBsAg-positive subjects (n = 236) and a random subset of HBsAg-negative subject (n = 172) were screened for HCV RNA using pooled plasma; positive samples were genotyped by core and NS5B sequencing. HCV antibodies were detected by three commercial screening assays and confirmed by the line immunoassay. HCV RNA was detected in 4/408 subjects (1.0%, 95% confidence interval 0.0–1.9%), comprising 3/ 236 (1.3%; 0.0–2.8%) HBsAg-positive and 1/172 (0.6%; 0.0–1.8%) HBsAg-negative subjects. HCV RNA-positive subjects showed reactivity in all three antibody screening assays. Among HCV RNA-negative subjects, 5/67 (7.5%), 5/67 (7.5%) and 19/67 (28.4%) showed antibody reactivity by each screening assay, respectively, including two (3.0%) with reactivity by all three assays. Only one sample (1.5%) had confirmed antibody reactivity by line immunoassay indicating past HCV infection. HCV-positive subjects (three males, two females) were aged 30–46 years, by questionnaire-based interview reported surgical procedures and blood transfusion as risk factors for infection. HCV genotypes were 2 (subtypes 2j, 2l, 2k/unassigned) and 1 (subtype unassigned). Without further testing, HCV antibody screening assays variably overestimated HCV prevalence among HIV-infected subjects in Ghana. These findings inform the interpretation of previous seroprevalence estimates based upon screening assays alone.
Assessing and Strengthening African Universities’ Capacity for Doctoral Programmes
(PLoS Medicine, 2011-09) Bates, Imelda; Phillips, Richard Odame; Martin-Peprah, Ruby; Kibiki, Gibson; Gaye, Oumar; et.al
Universities can make a major contribution to good policy-making by generating nationally relevant evidence, but little is known about how to strategically support universities in poorer countries to train and nurture sufficient internationally competitive researchers. N It is difficult for universities to develop a coherent strategy to identify and remedy deficiencies in their doctoral training programmes because there is currently no single process that can be used to evaluate all the components needed to make these programmes successful. N We have developed an evidence-based process for evaluating doctoral programmes from multiple perspectives that comprises an interview guide and a list of corroborating documents and facilities; we refined and validated this process by testing it in five diverse African universities. N The strategy and priority list that emerged from the evaluation process facilitated ‘‘buy-in’’ from internal and external agencies and enabled each university to lead the development, implementation, and monitoring of their own strategy for remedying doctoral programme deficiencies.
Buruli ulcer disease: prospects for a vaccine
(Med Microbiol Immunol, 2009-02-07) Huygen, Kris; Phillips, Richard Odame; Adjei, Ohene Adjei; Affolabi, Dissou; Bretzel, Gisela; et.al
Buruli ulcer disease (BUD), caused by Mycobacterium ulcerans, is a neglected bacterial infection of the poor in remote rural areas, mostly affecting children. BUD is a mutilating disease leading to severe disability; it is the third most common mycobacterial infection in immunocompetent people after tuberculosis and leprosy. It is most endemic in West Africa, but cases have been reported from more than 30 countries. Treatment with antibiotics is possible, long-lasting and requires injections; there are cases of treatment failures, and the disease is prone to resistance. A vaccine against M. ulcerans would protect persons at risk in highly endemic areas, and could be used as a therapeutic vaccine to shorten the duration of treatment and prevent relapses. There is considerable evidence supporting the
Buruli ulcer treatment: Rate of surgical intervention differs highly between treatment centers in West Africa
(PLOS Neglected Tropical Diseases, 2019-10-28) Phillips, Richard Odame; Wadagni, Anita C.; Steinhorst, Jonathan; Barogui, Yves T.; Catraye, P. M.; et. al
Background Antibiotic treatment proved itself as the mainstay of treatment for Buruli ulcer disease. This neglected tropical disease is caused by Mycobacterium ulcerans. Surgery persists as an adjunct therapy intended to reduce the mycobacterial load. In an earlier clinical trial, patients benefited from delaying the decision to operate. Nevertheless, the rate of surgical interventions differs highly per clinic. Methods A retrospective study was conducted in six different Buruli ulcer (BU) treatment centers in Benin and Ghana. BU patients clinically diagnosed between January 2012 and December 2016 were included and surgical interventions during the follow-up period, at least one year after diagnosis, were recorded. Logistic regression analysis was carried out to estimate the effect of the treatment center on the decision to perform surgery, while controlling for interaction and confounders. Results A total of 1193 patients, 612 from Benin and 581 from Ghana, were included. In Benin, lesions were most frequently (42%) categorized as the most severe lesions (WHO criteria, category III), whereas in Ghana lesions were most frequently (44%) categorized as small lesions (WHO criteria, category I). In total 344 (29%) patients received surgical intervention. The percentage of patients receiving surgical intervention varied between hospitals from 1.5% to 72%. Patients treated in one of the centers in Benin were much more likely to have surgery compared to the clinic in Ghana with the lowest rate of surgical intervention (RR =46.7 CI 95% [17.5–124.8]). Even after adjusting for confounders (severity of disease, age, sex, limitation of movement at joint at time of diagnosis, ulcer and critical sites), rates of surgical interventions varied highly. Conclusion The decision to perform surgery to reduce the mycobacterial load in BU varies highly per clinic. Evidence based guidelines are needed to guide the role of surgery in the treatment of BU
Candidatus Neoehrlichia mikurensis and Anaplasma phagocytophilum in Urban Hedgehogs
(Emerging Infectious Diseases, 2014-03) Kollie, Karsor; Amoako, Yaw Ampem; Ake, Julien; Mulbah, Tarnue; Phillips, Richard Odame; et.al
Candidatus Neoehrlichia mikurensis is a member of the order Rickettsiales, family Anaplasmataceae (1). Manifestations of infection with these bacteria are atypical and severe and include cough, nausea, vomiting, anemia, headache, pulmonary infiltration, malaise, myalgia, arthralgia, fatigue, recurrent fever for ≤8 months, and/or death (2–5). Candidatus N. mikurensis has been detected in Ixodes ovatus, I. persulcatus, and Haemaphysalis concinna ticks in Asia (1,5). Candidatus N. mikurensis has been identified as one of the most prevalent pathogenic agents in I. ricinus ticks throughout Europe (2,3,6). Rodents of diverse species and geographic origins have been shown to carry these bacteria, but transmission experiments have not been conducted to unambiguously identify natural vertebrate reservoirs (1–3,5–7). This emerging tickborne pathogen has been detected mainly in immunocompromised patients in Sweden (n = 1), Switzerland (n = 3), Germany (n = 2), and the Czech Republic (n = 2) and in immunocompetent patients in China (n = 7) (2–5). Anaplasma phagocytophilum is an obligate, intracellular, tickborne bacterium of the family Anaplasmataceae and causes granulocytic anaplasmosis in humans and domestic animals. In Europe, I. ricinus ticks are its major vector, and red deer, roe deer, rodents, and European hedgehogs (Erinaceus europaeus) are suspected reservoir hosts (8).
CD27 expression of T-cells discriminates IGRA-negative TB patients from healthy contacts in Ghana
(Elsevier Masson SAS, 2019) Phillips, Richard Odame; Adankwah, Ernest; Güler, Alptekin; Mayatepek, Ertan; Nausch, Norman; et. al
IFN-g release assays (IGRAs) have suboptimal sensitivity for detection of Mycobacterium tuberculosis (Mtb) infection and cannot discriminate between tuberculosis (TB) patients and healthy -potentially Mtb infected- contacts (HCs). In a case-control study, we determined T-cell phenotypes of IGRAs in TB patients (n ¼ 20) and HCs (n ¼ 20) from Ghana. CD27 expression of T-cells was significantly lower in TB patients as compared to HCs independent from Mtb-specificity. CD27 expression discriminated both study groups - including TB patients with low or indeterminate IGRA results - effectively. We conclude that CD27 is a promising biomarker for diagnosis of TB patients with inconclusive IGRA results.
Clinical and Bacteriological Efficacy of Rifampin-Streptomycin Combination for Two Weeks followed by Rifampin and Clarithromycin for Six Weeks for Treatment of Mycobacterium ulcerans Disease
(Antimicrobial Agents and Chemotherapy, 2014-02) Phillips, Richard Odame; Sarfo, Fred Stephen; Abass, Mohammed K.; Abotsi, Justice; Wilson, Tuah; Forson, Mark; Amoako, Yaw A.; Thompson, William; Asiedu, Kingsley; Wansbrough-Jonesc, Mark Wansbrough-Jonesc
Buruli ulcer, an ulcerating skin disease caused by Mycobacterium ulcerans infection, is common in tropical areas of western Africa. We determined the clinical and microbiological responses to administration of rifampin and streptomycin for 2 weeks followed by administration of rifampin and clarithromycin for 6 weeks in 43 patients with small laboratory-confirmed Buruli lesions and monitored for recurrence-free healing. Bacterial load in tissue samples before and after treatment for 6 and 12 weeks was monitored by semiquantitative culture. The success rate was 93%, and there was no recurrence after a 12-month follow-up. Eight percent had a positive culture 4 weeks after antibiotic treatment, but their lesions went on to heal. The findings indicate that rifampin and clarithromycin can replace rifampin and streptomycin for the continuation phase after rifampin and streptomycin administration for 2 weeks without any apparent loss of efficacy.
Clinical and Bacteriological Efficacy of Rifampin-Streptomycin Combination for Two Weeks followed by Rifampin and Clarithromycin for Six Weeks for Treatment of Mycobacterium ulcerans Disease
(Antimicrobial Agents and Chemotherapy, 2014-02) Phillips, Richard Odame; Sarfo, Fred S.; Abass, Mohammed K.; Abotsi, Justice; Wilson, Tuah; et.al
Buruli ulcer, an ulcerating skin disease caused by Mycobacterium ulcerans infection, is common in tropical areas of western Africa. We determined the clinical and microbiological responses to administration of rifampin and streptomycin for 2 weeks followed by administration of rifampin and clarithromycin for 6 weeks in 43 patients with small laboratory-confirmed Buruli lesions and monitored for recurrence-free healing. Bacterial load in tissue samples before and after treatment for 6 and 12 weeks was monitored by semiquantitative culture. The success rate was 93%, and there was no recurrence after a 12-month follow-up. Eight percent had a positive culture 4 weeks after antibiotic treatment, but their lesions went on to heal. The findings indicate that rifampin and clarithromycin can replace rifampin and streptomycin for the continuation phase after rifampin and streptomycin administration for 2 weeks without any apparent loss of efficacy.
Clinical and microbiological predictors of healing in Buruli ulcer disease
(Journal of Clinical Tuberculosis and Other Mycobacterial Diseases, 2024-02) Agbavor, Bernadette; Agbanyo, Abigail; Laglo, Aloysius Dzigbordi; Antwi, Philemon Bosiako; Ackam, Nancy; Adjei, Jonathan; Frimpong, Venus; Boampong, Kwadwo; Frimpong, Michael; Addo, Matthew Glover; Wansbrough-Jones, Mark; Amoako, Yaw Ampem; Phillips, Richard Odame; 0000-0001-5014-6153
Introduction: Wound measurements are relevant in monitoring the rate of healing (RoH) and may predict time to healing. Predicting the time to healing can help improve the management of Buruli ulcer. We examine three methods for the determination of RoH and their use as predictors of time to healing. Methods: Lesion measurements of Buruli ulcer patients treated from 2007 to 2022 were obtained with acetate sheet tracings (2D) or Aranz software (3D) fortnightly. RoH was determined using the absolute area, percentage area reduction and linear methods at 4 weeks post onset of antibiotic treatment. Predicted time to healing was compared to the actual healing time. Baseline characteristics were assessed for associations with healing. Results: All three methods for calculating the RoH significantly distinguished between fast and slow healers (p <0.0001). The predicted healing time using the linear method was comparable to the actual healing time for fast healers (p = 0.34). The RoH was influenced by the form of lesion, with plaques [OR 2.19 5 %CI (1.2–3.6), p =0.009], and oedemas [OR 8.5; 95 %CI (1.9––36.9), p = 0.004] being associated with delayed healing. The proportion of patients with paradoxical reactions 16 % vs 3 %, p < 0.0001), higher baseline bacterial load (75/104;72 % vs 21/47;45 %, p = 0.001) and delayed clearance of viable organisms (71/104;68 % vs 9/47;19 %, p <0.0001) was higher in the slow healers than the fast healers. Conclusion: Predicted healing rates were comparatively lower for slow healers than fast healers. Baseline characteristics associated with healing can be explored for an improved disease management plan to reduce patient and caregiver anxiety.
Clinical Efficacy of Combination of Rifampin and Streptomycin for Treatment of Mycobacterium ulcerans Disease
(Antimicrobial Agents and Chemotherapy, 2010-09) Sarfo, Fred Stephen; Phillips, Richard Odame; Asiedu, Kingsley; Ampadu, Edwin; Bobi, Nana; et.al
We have evaluated the clinical efficacy of the combination of oral rifampin at 10 mg/kg of body weight and intramuscular streptomycin at 15 mg/kg for 8 weeks (RS8), as recommended by the WHO, in 160 PCRconfirmed cases of Mycobacterium ulcerans disease. In 152 patients (95%) with all forms of disease from early nodules to large ulcers, with or without edema, the lesions healed without recourse to surgery. Eight patients whose ulcers were healing poorly had skin grafting after completion of antibiotics. There were no recurrences among 158 patients reviewed at the 1-year follow-up. The times to complete healing ranged from 2 to 48 weeks, according to the type and size of the lesion, but the average rate of healing (rate of reduction in ulcer diameter) varied widely. Thirteen subjects had positive cultures for M. ulcerans during or after treatment, but all the lesions healed without further antibiotic treatment. Adverse events were rare. These results confirm the efficacy of RS8 delivered in a community setting.
Combined Inflammatory and Metabolic Defects Reflected by Reduced Serum Protein Levels in Patients with Buruli Ulcer Disease
(PLOS Neglected Tropical Diseases, 2014-04-10) Phillips, Richard Odame; Sarfo, Fred Stephen; Landier, Jordi; Oldenburg, Reid; Frimpong, Michael; et. al
Buruli ulcer is a skin disease caused by Mycobacterium ulcerans that is spreading in tropical countries, with major public health and economic implications in West Africa. Multi-analyte profiling of serum proteins in patients and endemic controls revealed that Buruli ulcer disease down-regulates the circulating levels of a large array of inflammatory mediators, without impacting on the leukocyte composition of peripheral blood. Notably, several proteins contributing to acute phase reaction, lipid metabolism, coagulation and tissue remodelling were also impacted. Their down-regulation was selective and persisted after the elimination of bacteria with antibiotic therapy. It involved proteins with various functions and origins, suggesting that M. ulcerans infection causes global and chronic defects in the host’s protein metabolism. Accordingly, patients had reduced levels of total serum proteins and blood urea, in the absence of signs of malnutrition, or functional failure of liver or kidney. Interestingly, slow healers had deeper metabolic and coagulation defects at the start of antibiotic therapy. In addition to providing novel insight into Buruli ulcer pathogenesis, our study therefore identifies a unique proteomic signature for this disease.
Comparison of Two Assays for Molecular Determination of Rifampin Resistance in Clinical Samples from Patients with Buruli Ulcer Disease
(Journal of Clinical Microbiology, 2014-01-29) Phillips, Richard Odame; Jansson, Moritz; Beissner, Marcus; Badziklou, Kossi; Piten, Ebekalisai; et. al
Buruli ulcer disease (BUD), caused by Mycobacterium ulcerans, involves the skin, subcutaneous fatty tissue, and bones and predominantly affects children 15 years of age. If left untreated, contractures may cause severe functional limitation. Standardized antimycobacterial treatment consists of rifampin (RMP) and streptomycin administered for 8 weeks. An oral regimen combiningRMPand clarithromycin is currently under clinical evaluation (1–3). Notwithstanding the efficiency of chemotherapy, treatment failures and various types of secondary lesions have been reported, suggesting the need for customized clinical management strategies (4–6).
Cytokine mRNA Expression in Mycobacteriam ulcerans-Infected Human Skin and Correlation with Local Inflammatory Response
(American Society for Microbiology, 2006-05) Phillips, Richard Odame; Horsfield, C.; Mangan, J.; Laing, K.; Etuaful, S.; et.al
Cytokine mRNA expression in biopsies of Mycobacterium ulcerans-infected human tissue was investigated using real-time PCR, and the findings were correlated with the clinical stages of disease and histopathologies. A broad range of cytokine mRNAs were detected in 16 early nodules and 28 late-stage ulcers, including those for the Th1 cytokines tumor necrosis factor alpha (TNF- ) and gamma interferon (IFN- ) and the Th2 cytokine interleukin 10 (IL-10). IFN- was strongly expressed in both nodules and ulcers, suggesting that a Th1 response begins early in the disease. There was a significantly higher expression of IL-8 and other proinflammatory cytokines in results from 32 biopsies with neutrophilia than in those from 12 biopsies without acute inflammation. Ten tissue samples containing granulomas showed high mRNA expression for IFN- , IL-1 , IL-12p35, IL-12p40, IL-15, and TNF- relative to 34 tissue samples without granulomas. These results suggest that the human immune response to M. ulcerans is similar to that seen with some other mycobacteria despite the presence of the toxin mycolactone in the tissues.
Cytokine Response to Antigen Stimulation of Whole Blood from Patients with Mycobacterium ulcerans Disease Compared to That from Patients with Tuberculosis
(American Society for Microbiology, 2006-02) Phillips, Richard Odame; Horsfield, C.; Kuijper, S.; Sarfo, Fred Stephen; Obeng-Baah, J.; et.al
Mycobacterium ulcerans disease (Buruli ulcer) is a skin-ulcerating infection common in some parts of the tropics. We have investigated cytokine secretion after stimulation of whole blood from Buruli ulcer (BU) patients in a region of endemicity in Ghana with M. ulcerans sonicate or culture filtrate antigens to investigate the development of the response over time and its specificity by comparison with the response to Mycobacterium tuberculosis sonicate in human immunodeficiency virus-negative tuberculosis patients. Significant gamma interferon (IFN- ) production in response to whole-blood stimulation with M. ulcerans sonicate was detected in patients with ulcers, which was higher than that in patients with nodules but similar to subjects with healed BU. The mean IFN- response in household contacts of BU patients was not significantly different from that in healthy control subjects from an area of nonendemicity. Results in patients with untreated, smear-positive pulmonary tuberculosis and tuberculosis patients on treatment for more than 2 weeks showed that BU patients responded better to M. ulcerans antigens than tuberculosis patients. In contrast, interleukin-10 results were higher in patients with active M. ulcerans disease than in those with healed lesions, but the pattern of response was similar to that seen in tuberculosis. A similar pattern of cytokine secretion was found using M. tuberculosis sonicate as an antigen. Neither of the two culture filtrate antigens of M. ulcerans appeared to be more specific than M. ulcerans sonicate. In the early stages of M. ulcerans disease there was a mixed Th1 and Th2 cytokine response, but the Th1 response emerged as the dominant type.
Detection of Highly Prevalent Hepatitis B Virus Coinfection among HIV-Seropositive Persons in Ghana
(American Society for Microbiology, 2010-09) Geretti, Anna Maria; Patel, Mauli; Sarfo, Fred Stephen; Phillips, Richard Odame; Chadwick, David; et.al
Simple hepatitis B surface antigen (HBsAg) tests may facilitate ascertainment of hepatitis B virus (HBV) infection in settings with high endemicity but limited infrastructure. We evaluated two rapid HBsAg tests and characterized HBV coinfection in a Ghanaian HIV-positive cohort. Samples from 838 patients were tested by the rapid assays Determine and Vikia and the reference assays Architect, Murex version 3, and Liaison Ultra. The assays were also evaluated using the 2nd International Standard, a seroconversion panel, and two mutant panels. HBsAg-positive samples underwent HBV DNA quantification by real-time PCR and surface and polymerase gene population sequencing. Overall, 140/838 patients (16.7%; 95% confidence interval, 14.2 to 19.2%) were HBsAg positive, and of these, 103/140 (73.6%) were e-antigen negative and 118/140 (84.3%) showed an HBV DNA level of >14 IU/ml (median, 8,279 IU/ml). Assay sensitivities and specificities were as follows: Architect, 97.9 and 99.6%; Liaison, 97.1 and 99.4%; Murex, 98.6 and 99.3%; Determine, 69.3 and 100%; and Vikia, 70.7 and 100%. With Determine, the limit of detection was >1.5 to 3.4 HBsAg IU/ml, and the median HBV DNA loads were 598 and 10,905 IU/ml in Determine-negative and -positive samples, respectively (P 0.0005). Results were similar with the Vikia assay. HBV DNA sequencing indicated infection with genotype E in 82/86 (95.3%) patients. HBsAg mutations affected assay performance, including a T123A mutant that escaped detection by Architect. Major drug resistance mutations were observed in 4/86 patients (4.6%). The prevalence of HBV coinfection was high in this HIV-positive Ghanaian cohort. The two rapid assays identified HBsAg-positive patients at risk for liver disease with high specificity, albeit with only moderate sensitivity.
Detection of Mycolactone A/B in Mycobacterium ulcerans–Infected Human Tissue
(PLoS Neglected Tropical Diseases, 2010-01-05) Sarfo, Fred Stephen; Phillips, Richard Odame; Rangers, Brian; Mahrous, Engy A.; Lee, Richard E.; et. al
Background: Mycobacterium ulcerans disease (Buruli ulcer) is a neglected tropical disease common amongst children in rural West Africa. Animal experiments have shown that tissue destruction is caused by a toxin called mycolactone. Methodology/Principal Findings: A molecule was identified among acetone-soluble lipid extracts from M. ulcerans (Mu)- infected human lesions with chemical and biological properties of mycolactone A/B. On thin layer chromatography this molecule had a retention factor value of 0.23, MS analyses showed it had an m/z of 765.6 [M+Na+] and on MS:MS fragmented to produce the core lactone ring with m/z of 429.4 and the polyketide side chain of mycolactone A/B with m/z of 359.2. Acetone-soluble lipids from lesions demonstrated significant cytotoxic, pro-apoptotic and anti-inflammatory activities on cultured fibroblast and macrophage cell lines. Mycolactone A/B was detected in all of 10 tissue samples from patients with ulcerative and pre-ulcerative Mu disease. Conclusions/Significance: Mycolactone can be detected in human tissue infected with Mu. This could have important implications for successful management of Mu infection by antibiotic treatment but further studies are needed to measure its concentration.
Detection of Viable Mycobacterium ulcerans in Clinical Samples by a Novel Combined 16S rRNA Reverse Transcriptase/IS2404 Real-Time qPCR Assay
(PLOS Neglected Tropical Diseases, 2012-08-28) Phillips, Richard Odame; Beissner, Marcus; Symank, Dominik; Amoako, Yaw Ampem; Awua-Boateng, Nana- Yaa; et. al
Buruli ulcer disease (BUD) caused by Mycobacterium ulcerans involves the skin and soft tissue. If left untreated, extensive destruction of tissue followed by scarring and contractures may lead to severe functional limitations. Following the introduction of standardized antimycobacterial chemotherapy with rifampicin and streptomycin, recurrence rates of less than 2% were reported. However, treatment failures occur and a variety of secondary lesions necessitating customized clinical management strategies have been reported. True recurrences by definition occur more than three months after completion of antibiotic treatment, are characterised by the presence of viable bacilli, and require a second course of antibiotics. ‘‘Non-healers’’ may harbour viable, possibly drug-resistant M. ulcerans strains and may benefit from surgical intervention. Early-onset immune-mediated paradoxical reactions emerging during or shortly after treatment do not contain viable bacilli and may heal under conventional wound care and/or minor surgery; lateonset secondary lesions presumably attributable to secondary infection foci may clear spontaneously through enhanced immune responses primed by initial treatment. None of the current diagnostic techniques is applicable to rapidly address the pivotal question of the presence of viable bacilli in non-healers and patients with secondary BUD lesions, and optimal time points for collection of follow-up samples have not yet been investigated. Therefore, to date treatment monitoring is mainly based on clinical observation [1– 5]. Reverse transcriptase assays targeting 16S rRNA and mRNA were successfully applied for the rapid detection of viable mycobacteria in clinical samples from patients with tuberculosis and leprosy [6,7]. To employ this technique for classification of BUD lesions and monitoring of treatment success we developed a M. ulcerans–specific RNA-based viability assay combining a 16S rRNA reverse transcriptase real-time PCR (RT-qPCR) to determine bacterial viability with an IS2404 quantitative real-time PCR (qPCR) for increased specificity and simultaneous quantification of bacilli.
Diagnostics for COVID-19: A case for field-deployable, rapid molecular tests for community surveillance
(Ghana Med J., 2020) Frimpong, Michael; Amoako, Yaw A.; Anim, Kwadwo B.; Ahor, Hubert S.; Yeboah Richmond; Arthur, Joshua; Dakorah, Justin S.; Gborgblovor, Delphine; Akrofi, Samuel; Owusu, Michael; Sylverken, Augustina Angelina; Binger, Tabea; Phillips, Richard Odame; Djan, Phyllis Sekyi; 0000-0003-1901-6793; 0000-0002-4642-789X; 0000-0001-5066-150X
Across the globe, the outbreak of the COVID-19 pandemic is causing distress with governments doing everything in their power to contain the spread of the novel coronavirus (SARS-CoV-2) to prevent morbidity and mortality. Actions are being implemented to keep health care systems from being overstretched and to curb the outbreak. Any policy responses aimed at slowing down the spread of the virus and mitigating its immediate effects on health care systems require a firm basis of information about the absolute number of currently infected people, growth rates, and locations/hotspots of infections. The only way to obtain this base of information is by conducting numerous tests in a targeted way. Currently, in Ghana, there is a centralized testing approach, that takes 4-5 days for samples to be shipped and tested at central reference laboratories with results communicated to the district, regional and national stakeholders. This delay in diagnosis increases the risk of ongoing transmission in communities and vulnerable institutions. We have validated, evaluated and deployed an innovative diagnostic tool on a mobile laboratory platform to accelerate the COVID-19 testing. A preliminary result of 74 samples from COVID-19 suspected cases has a positivity rate of 12% with a turn-around time of fewer than 3 hours from sample taking to reporting of results, significantly reducing the waiting time from days to hours, enabling expedient response by the health system for contact tracing to reduce transmission and additionally improving case management.
Dynamics of the Cytokine Response to Mycobacterium ulcerans during Antibiotic Treatment for M. ulcerans Disease (Buruli Ulcer) in Humans
(American Society for Microbiology, 2009-01) Sarfo, Fred Stephen; Phillips, Richard Odame; Ampadu, E.; Sarpong, F.; Adentwe, E.; et.al
We have studied the evolution of the gamma interferon (IFN- ) and interleukin 10 (IL-10) responses after Mycobacterium ulcerans sonicate stimulation of whole blood from patients with early M. ulcerans lesions during treatment with rifampin and streptomycin for 8 weeks. Among the 26 patients, secretion of IFN- increased during treatment, with a significant increase at 4 weeks and a further increase after 8 weeks overall. The increase was more rapid in patients with large or ulcerative lesions, becoming significant by 4 weeks. For small lesions, there was only a minor increase, which did not reach significance. There was no significant change in the median IL-10 response during antibiotic therapy, and there was no inverse correlation between IFN- and IL-10 responses. These results demonstrate that an IFN- secretory response to M. ulcerans developed, independently of IL-10 secretion, in patients whose M. ulcerans disease healed during antibiotic therapy.
Efficacy of the Combination Rifampin-Streptomycin in Preventing Growth of Mycobacterium ulcerans in Early Lesions of Buruli Ulcer in Humans
(American Society for Microbiology, 2005-04-29) Etuaful, S.; Carbonnelle, B.; Phillips, Richard Odame; Evans, M.; Ofori-Adjei, D.; et.al
Mycobacterium ulcerans disease is common in some humid tropical areas, particularly in parts of West Africa, and current management is by surgical excision of skin lesions ranging from early nodules to extensive ulcers (Buruli ulcer). Antibiotic therapy would be more accessible to patients in areas of Buruli ulcer endemicity. We report a study of the efficacy of antibiotics in converting early lesions (nodules and plaques) from culture positive to culture negative. Lesions were excised either immediately or after treatment with rifampin orally at 10 mg/kg of body weight and streptomycin intramuscularly at 15 mg/kg of body weight daily for 2, 4, 8, or 12 weeks and examined by quantitative bacterial culture, PCR, and histopathology for M. ulcerans. Lesions were measured during treatment. Five lesions excised without antibiotic treatment and five lesions treated with antibiotics for 2 weeks were culture positive, whereas three lesions treated for 4 weeks, five treated for 8 weeks, and three treated for 12 weeks were culture negative. No lesions became enlarged during antibiotic treatment, and most became smaller. Treatment with rifampin and streptomycin for 4 weeks or more inhibited growth of M. ulcerans in human tissue, and it provides a basis for proceeding to a trial of antibiotic therapy as an alternative to surgery for early M. ulcerans disease.

Browsing by Author "Phillips, Richard Odame"

Results Per Page

Sort Options