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Njovu IK, Nalumaga PP, Ampaire L, Nuwagira E, Mwesigye J, Musinguzi B, Kassaza K, Taseera K, Kiguli Mukasa J, Bazira J, Iramiot JS, Baguma A, Bongomin F, Kwizera R, Achan B, Cox MJ, King JS, May R, Ballou ER, Itabangi H. Investigating Metabolic and Molecular Ecological Evolution of Opportunistic Pulmonary Fungal Coinfections: Protocol for a Laboratory-Based Cross-Sectional Study. JMIR Res Protoc 2023; 12:e48014. [PMID: 37581914 PMCID: PMC10466149 DOI: 10.2196/48014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2023] [Revised: 05/25/2023] [Accepted: 05/26/2023] [Indexed: 08/16/2023] Open
Abstract
BACKGROUND Fungal-bacterial cocolonization and coinfections pose an emerging challenge among patients suspected of having pulmonary tuberculosis (PTB); however, the underlying pathogenic mechanisms and microbiome interactions are poorly understood. Understanding how environmental microbes, such as fungi and bacteria, coevolve and develop traits to evade host immune responses and resist treatment is critical to controlling opportunistic pulmonary fungal coinfections. In this project, we propose to study the coexistence of fungal and bacterial microbial communities during chronic pulmonary diseases, with a keen interest in underpinning fungal etiological evolution and the predominating interactions that may exist between fungi and bacteria. OBJECTIVE This is a protocol for a study aimed at investigating the metabolic and molecular ecological evolution of opportunistic pulmonary fungal coinfections through determining and characterizing the burden, etiological profiles, microbial communities, and interactions established between fungi and bacteria as implicated among patients with presumptive PTB. METHODS This will be a laboratory-based cross-sectional study, with a sample size of 406 participants. From each participant, 2 sputa samples (one on-spot and one early morning) will be collected. These samples will then be analyzed for both fungal and bacterial etiology using conventional metabolic and molecular (intergenic transcribed spacer and 16S ribosomal DNA-based polymerase chain reaction) approaches. We will also attempt to design a genome-scale metabolic model for pulmonary microbial communities to analyze the composition of the entire microbiome (ie, fungi and bacteria) and investigate host-microbial interactions under different patient conditions. This analysis will be based on the interplays of genes (identified by metagenomics) and inferred from amplicon data and metabolites (identified by metabolomics) by analyzing the full data set and using specific computational tools. We will also collect baseline data, including demographic and clinical history, using a patient-reported questionnaire. Altogether, this approach will contribute to a diagnostic-based observational study. The primary outcome will be the overall fungal and bacterial diagnostic profile of the study participants. Other diagnostic factors associated with the etiological profile, such as incidence and prevalence, will also be analyzed using univariate and multivariate schemes. Odds ratios with 95% CIs will be presented with a statistical significance set at P<.05. RESULTS The study has been approved by the Mbarara University Research Ethic Committee (MUREC1/7-07/09/20) and the Uganda National Council of Science and Technology (HS1233ES). Following careful scrutiny, the protocol was designed to enable patient enrollment, which began in March 2022 at Mbarara University Teaching Hospital. Data collection is ongoing and is expected to be completed by August 2023, and manuscripts will be submitted for publication thereafter. CONCLUSIONS Through this protocol, we will explore the metabolic and molecular ecological evolution of opportunistic pulmonary fungal coinfections among patients with presumptive PTB. Establishing key fungal-bacterial cross-kingdom synergistic relationships is crucial for instituting fungal bacterial coinfecting etiology. TRIAL REGISTRATION ISRCTN Registry ISRCTN33572982; https://tinyurl.com/caa2nw69. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID) DERR1-10.2196/48014.
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Affiliation(s)
- Israel Kiiza Njovu
- Medical Mycology Unit, Department of Microbiology, Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda
| | - Pauline Petra Nalumaga
- Medical Mycology Unit, Department of Microbiology, Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda
| | - Lucas Ampaire
- Department of Medical Laboratory Sciences, Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda
| | - Edwin Nuwagira
- Department of Internal Medicine, Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda
| | - James Mwesigye
- Medical Mycology Unit, Department of Microbiology, Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda
| | - Benson Musinguzi
- Department of Medical Laboratory Science, Faculty of Health Sciences, Muni University, Arua, Uganda
| | - Kennedy Kassaza
- Medical Mycology Unit, Department of Microbiology, Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda
| | - Kabanda Taseera
- Medical Mycology Unit, Department of Microbiology, Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda
| | - James Kiguli Mukasa
- Department of Microbiology and Immunology, School of Health Sciences, Soroti University, Soroti, Uganda
| | - Joel Bazira
- Medical Mycology Unit, Department of Microbiology, Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda
| | - Jacob Stanley Iramiot
- Mycology Unit, Department of Microbiology and Immunology, Busitema University, Mbale, Uganda
| | - Andrew Baguma
- Department of Microbiology, School of Medicine, Kabale University, Kabale, Uganda
| | - Felix Bongomin
- Department of Microbiology and Immunology, Faculty of Medicine, Gulu University, Gulu, Uganda
| | - Richard Kwizera
- Infectious Diseases Institute, College of Health Sciences, Makerere University, Kampala, Uganda
| | - Beatrice Achan
- Department of Microbiology, School of Biomedical Sciences, College of Health Sciences, Makerere University, Kampala, Uganda
| | - Michael J Cox
- Institute of Microbiology and Infection, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Jason S King
- School of Biosciences, Sheffield University, Sheffield, United Kingdom
| | - Robin May
- Institute of Microbiology and Infection, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Elizabeth R Ballou
- Medical Research Council Centre for Medical Mycology, University of Exeter, Exeter, United Kingdom
| | - Herbert Itabangi
- Medical Mycology Unit, Department of Microbiology, Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda
- Mycology Unit, Department of Microbiology and Immunology, Busitema University, Mbale, Uganda
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Kassaza K, Wasswa F, Nielsen K, Bazira J. Cryptococcus neoformans Genotypic Diversity and Disease Outcome among HIV Patients in Africa. J Fungi (Basel) 2022; 8:jof8070734. [PMID: 35887489 PMCID: PMC9325144 DOI: 10.3390/jof8070734] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 06/24/2022] [Accepted: 07/06/2022] [Indexed: 11/16/2022] Open
Abstract
Cryptococcal meningoencephalitis, a disease with poor patient outcomes, remains the most prevalent invasive fungal infection worldwide, accounting for approximately 180,000 deaths each year. In several areas of sub-Saharan Africa with the highest HIV prevalence, cryptococcal meningitis is the leading cause of community-acquired meningitis, with a high mortality among HIV-infected individuals. Recent studies show that patient disease outcomes are impacted by the genetics of the infecting isolate. Yet, there is still limited knowledge of how these genotypic variations contribute to clinical disease outcome. Further, it is unclear how the genetic heterogeneity of C. neoformans and the extensive phenotypic variation observed between and within isolates affects infection and disease. In this review, we discuss current knowledge of how various genotypes impact disease progression and patient outcome in HIV-positive populations in sub-Saharan African, a setting with a high burden of cryptococcosis.
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Affiliation(s)
- Kennedy Kassaza
- Department of Microbiology and Parasitology, Mbarara University of Science and Technology, Mbarara P.O. Box 1410, Uganda; (K.K.); (F.W.)
| | - Fredrickson Wasswa
- Department of Microbiology and Parasitology, Mbarara University of Science and Technology, Mbarara P.O. Box 1410, Uganda; (K.K.); (F.W.)
| | - Kirsten Nielsen
- Department of Microbiology and Immunology, University of Minnesota, Minneapolis, MN 55455, USA
- Correspondence: (K.N.); (J.B.)
| | - Joel Bazira
- Department of Microbiology and Parasitology, Mbarara University of Science and Technology, Mbarara P.O. Box 1410, Uganda; (K.K.); (F.W.)
- Correspondence: (K.N.); (J.B.)
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Micheni LN, Kassaza K, Kinyi H, Ntulume I, Bazira J. Detection of Mycobacterium tuberculosis multiple strains in sputum samples from patients with pulmonary tuberculosis in south western Uganda using MIRU-VNTR. Sci Rep 2022; 12:1656. [PMID: 35102181 PMCID: PMC8803872 DOI: 10.1038/s41598-022-05591-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2021] [Accepted: 01/11/2022] [Indexed: 11/25/2022] Open
Abstract
Infections with multiple strains of Mycobacterium tuberculosis are now widely recognized as a common occurrence. Identification of patients infected with multiple strains provides both insight into the disease dynamics and the epidemiology of tuberculosis. Analysis of Mycobacterial Interspersed Repetitive Unit-Variable-Number Tandem Repeats (MIRU-VNTR) has been shown to be highly sensitive in detecting multiple M. tuberculosis strains even in sputum. The goal of this study was to identify cases of multiple M. tuberculosis strain infections among patients diagnosed with pulmonary tuberculosis in Southwestern Uganda and assessment of factors associated with multiple strain infections. DNA extracted directly from 78 sputum samples, each from an individual patient, was analyzed using the standard 24 loci MIRU-VNTR typing. Five (6.4%) of the 78 patients were infected with multiple strains of M. tuberculosis with all of them being the newly diagnosed cases while two-thirds of them were co-infected with HIV. Exact regression analysis projected that the natives were more likely to harbor multiple strains (OR; 0.981, 95% CI 0–7.926) as well as those with a high microbial load (OR; 0.390, 95% CI 0–3.8167). Despite these findings being not statistically significant due to the small sample size, this points to a critical component of disease dynamics that has clinical implications and emphasizes a need for a study using a larger cohort. It is also essential to study the potential factors associated with higher risk of exposure to newly diagnosed and HIV positive patients at the community level. In addition, our ability to detect multiple M. tuberculosis strains using the standard 24 loci MIRU-VNTR typing especially with allelic diversity in loci 2059 and 3171, which are excluded from the 15-locus MIRU-VNTR, lead us to recommend the use of this genotyping technique, especially in areas with tuberculosis endemicity similar to this study.
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Affiliation(s)
- Lisa Nkatha Micheni
- Department of Microbiology, Mbarara University of Science and Technology, Box 1410, Mbarara, Uganda. .,Department of Microbiology and Immunology, Kampala International University Western Campus, Box 71, Bushenyi, Uganda.
| | - Kennedy Kassaza
- Department of Microbiology, Mbarara University of Science and Technology, Box 1410, Mbarara, Uganda
| | - Hellen Kinyi
- Department of Biochemistry, School of Medicine, Kabale University, Box 317, Kabale, Uganda
| | - Ibrahim Ntulume
- Department of Microbiology and Immunology, Kampala International University Western Campus, Box 71, Bushenyi, Uganda
| | - Joel Bazira
- Department of Microbiology, Mbarara University of Science and Technology, Box 1410, Mbarara, Uganda.
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Manirakiza G, Kassaza K, Taremwa IM, Bazira J, Byarugaba F. Molecular identification and anti-malarial drug resistance profile of Plasmodium falciparum from patients attending Kisoro Hospital, southwestern Uganda. Malar J 2022; 21:21. [PMID: 35033082 PMCID: PMC8761270 DOI: 10.1186/s12936-021-04023-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2021] [Accepted: 12/14/2021] [Indexed: 11/22/2022] Open
Abstract
Background The evolution of malaria infection has necessitated the development of highly sensitive diagnostic assays, as well as the use of dried blood spots (DBS) as a potential source of deoxyribonucleic acid (DNA) yield for polymerase chain reaction (PCR) assays. This study identified the different Plasmodium species in malaria-positive patients, and the anti-malarial drug resistance profile for Plasmodium falciparum using DBS samples collected from patients attending Kisoro Hospital in Kisoro district, Southwestern Uganda. Methods The blood samples were prospectively collected from patients diagnosed with malaria to make DBS, which were then used to extract DNA for real-time PCR and high-resolution melting (HRM) analysis. Plasmodium species were identified by comparing the control and test samples using HRM-PCR derivative curves. Plasmodium falciparum chloroquine (CQ) resistance transporter (pfcrt) and kelch13 to screen the samples for anti-malarial resistance markers. The HRM-PCR derivative curve was used to present a summary distribution of the different Plasmodium species as well as the anti-malarial drug profile. Results Of the 152 participants sampled, 98 (64.5%) were females. The average age of the participants was 34.9 years (range: 2 months–81 years). There were 134 samples that showed PCR amplification, confirming the species as Plasmodium. Plasmodium falciparum (N = 122), Plasmodium malariae (N = 6), Plasmodium ovale (N = 4), and Plasmodium vivax (N = 2) were the various Plasmodium species and their proportions. The results showed that 87 (71.3%) of the samples were sensitive strains/wild type (CVMNK), 4 (3.3%) were resistant haplotypes (SVMNT), and 31 (25.4%) were resistant haplotypes (CVIET). Kelch13 C580Y mutation was not detected. Conclusion The community served by Kisoro hospital has a high Plasmodium species burden, according to this study. Plasmodium falciparum was the dominant species, and it has shown that resistance to chloroquine is decreasing in the region. Based on this, molecular identification of Plasmodium species is critical for better clinical management. Besides, DBS is an appropriate medium for DNA preservation and storage for future epidemiological studies.
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Affiliation(s)
- Godfrey Manirakiza
- Department of Microbiology, Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda.
| | - Kennedy Kassaza
- Department of Microbiology, Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda
| | - Ivan Mugisha Taremwa
- Institute of Allied Health Sciences, Clarke International University, Kampala, Uganda
| | - Joel Bazira
- Department of Microbiology, Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda
| | - Fredrick Byarugaba
- Department of Microbiology, Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda
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Micheni LN, Kassaza K, Kinyi H, Ntulume I, Bazira J. Rifampicin and isoniazid drug resistance among patients diagnosed with pulmonary tuberculosis in southwestern Uganda. PLoS One 2021; 16:e0259221. [PMID: 34714879 PMCID: PMC8555815 DOI: 10.1371/journal.pone.0259221] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Accepted: 10/18/2021] [Indexed: 11/18/2022] Open
Abstract
Multidrug-resistant tuberculosis (MDR-TB) has become a major threat to the control of tuberculosis globally. Uganda is among the countries with a relatively high prevalence of tuberculosis despite significant control efforts. In this study, the drug resistance of Mycobacterium tuberculosis to rifampicin (RIF) and isoniazid (INH) was investigated among patients diagnosed with pulmonary tuberculosis in Southwestern Uganda. A total of 283 sputum samples (266 from newly diagnosed and 17 from previously treated patients), collected between May 2018 and April 2019 at four different TB diagnostic centres, were assessed for RIF and INH resistance using high-resolution melt curve analysis. The overall prevalence of monoresistance to INH and RIF was 8.5% and 11% respectively, while the prevalence of MDR-TB was 6.7%. Bivariate analysis showed that patients aged 25 to 44 years were at a higher risk of developing MDR-TB (cOR 0.253). Furthermore, among the newly diagnosed patients, the prevalence of monoresistance to INH, RIF and MDR-TB was 8.6%, 10.2% and 6.4% respectively; while among the previously treated cases, these prevalence rates were 5.9%, 23.5% and 11.8%. These rates are higher than those reported previously indicating a rise in MTB drug resistance and may call for measures used to prevent a further rise in drug resistance. There is also a need to conduct frequent drug resistance surveys, to monitor and curtail the development and spread of drug-resistant TB.
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Affiliation(s)
- Lisa Nkatha Micheni
- Department of Microbiology, Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda
- Department of Microbiology and Immunology, Faculty of Biomedical Sciences, Kampala International University Western Campus, Bushenyi, Uganda
| | - Kennedy Kassaza
- Department of Microbiology, Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda
| | - Hellen Kinyi
- Department of Biochemistry, School of Medicine, Kabale University, Kabale, Uganda
| | - Ibrahim Ntulume
- Department of Microbiology and Immunology, Faculty of Biomedical Sciences, Kampala International University Western Campus, Bushenyi, Uganda
| | - Joel Bazira
- Department of Microbiology, Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda
- * E-mail:
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Njovu IK, Musinguzi B, Mwesigye J, Kassaza K, Turigurwa J, Nuwagira E, Bazira J, Kabanda T, Mpeirwe M, Ampaire L, Mutekanga A, Kiguli J, Achan B, Itabangi H. Status of pulmonary fungal pathogens among individuals with clinical features of pulmonary tuberculosis at Mbarara University Teaching Hospital in Southwestern Uganda. Ther Adv Infect Dis 2021; 8:20499361211042477. [PMID: 34484738 PMCID: PMC8411620 DOI: 10.1177/20499361211042477] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2021] [Accepted: 08/10/2021] [Indexed: 12/15/2022] Open
Abstract
Background: Pulmonary mycoses are important diseases of the respiratory tract caused by
pulmonary fungal pathogens. These pathogens are responsible for significant
morbidity and mortality rates worldwide; however, less attention has been
paid to them. In this study we determined the prevalence of pulmonary fungal
pathogens among individuals with clinical features of pulmonary tuberculosis
at Mbarara Regional Referral Hospital. Method: This was a hospital based cross sectional survey. Sputum samples were
collected from each study participant. For each sample, the following tests
were performed: Sabouraud dextrose agar for fungal culture, GeneXpert for
Mycobacteria tuberculosis (MTB) and potassium hydroxide
for fungal screening. Filamentous fungal growth and yeasts were further
examined with lactophenol cotton blue staining and germ tube
respectively. Results: Out of 113 study participants, 80 (70.7%) had pulmonary fungal pathogens
whilst those with pulmonary tuberculosis numbered five (4.4%).
Candida albicans [21 (22.58%)] and
Aspergillus species [16 (17.20%)] were the pathogens
most identified among others. Two (1.7%) TB GeneXpert positive participants
had fungal pathogens isolated from their sputum samples. We established a
prevalence of 57 (71.3%) for pulmonary fungal pathogen (PFP) isolates, three
(60.0%) for MTB in HIV positive patients and 18 (22.5%) for PFP, and zero
(0.0%) for MTB in HIV negative patients. On the other hand, two (100%) HIV
positive patients had both PFP isolates and MTB. Conclusion: Our findings highlight the diversity of neglected pulmonary fungal pathogens
whose known medical importance in causing pulmonary mycoses cannot be
overemphasised. Therefore this presents a need for routine diagnosis for
pulmonary mycoses among TB suspects and set-up of antimicrobial profile for
pulmonary fungal isolates to support clinical management of these cases.
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Affiliation(s)
- Israel Kiiza Njovu
- Department of Microbiology, Mycology Unit, Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda
| | - Benson Musinguzi
- Department of Medical Laboratory Science, Faculty of Health Sciences, Muni University, Arua, Uganda
| | - James Mwesigye
- Department of Microbiology, Mycology Unit, Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda
| | - Kennedy Kassaza
- Department of Microbiology, Mycology Unit, Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda
| | - Joseph Turigurwa
- Department of Microbiology, Mycology Unit, Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda
| | - Edwin Nuwagira
- Department of Microbiology, Mycology Unit, Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda
| | - Joel Bazira
- Department of Microbiology, Mycology Unit, Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda
| | - Taseera Kabanda
- Department of Microbiology, Mycology Unit, Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda
| | - Moses Mpeirwe
- Department of Microbiology, Mycology Unit, Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda
| | - Lucas Ampaire
- Department of Medical Laboratory Sciences, Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda
| | - Andrew Mutekanga
- Department of Internal Medicine, Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda
| | - James Kiguli
- Department of Microbiology and Immunology, School of Health Sciences, Soroti University, Soroti, Uganda
| | - Beatrice Achan
- Department of Microbiology, School of Biomedical Sciences, Makerere University, Uganda
| | - Herbert Itabangi
- Department of Microbiology, Mycology Unit, Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda
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Kassaza K, Long AC, McDaniels JM, Andre M, Fredrickson W, Nyehangane D, Orikiriza P, Operario DJ, Bazira J, Mwanga-Amumpaire JA, Moore CC, Guler JL, Boum Y. Surveillance of Plasmodium falciparum pfcrt haplotypes in southwestern uganda by high-resolution melt analysis. Malar J 2021; 20:114. [PMID: 33632242 PMCID: PMC7908690 DOI: 10.1186/s12936-021-03657-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Accepted: 02/18/2021] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Chloroquine (CQ) resistance is conferred by mutations in the Plasmodium falciparum CQ resistance transporter (pfcrt). Following CQ withdrawal for anti-malarial treatment, studies across malaria-endemic countries have shown a range of responses. In some areas, CQ sensitive parasites re-emerge, and in others, mutant haplotypes persist. Active surveillance of resistance mutations in clinical parasites is essential to inform treatment regimens; this effort requires fast, reliable, and cost-effective methods that work on a variety of sample types with reagents accessible in malaria-endemic countries. METHODS Quantitative PCR followed by High-Resolution Melt (HRM) analysis was performed in a field setting to assess pfcrt mutations in two groups of clinical samples from Southwestern Uganda. Group 1 samples (119 in total) were collected in 2010 as predominantly Giemsa-stained slides; Group 2 samples (125 in total) were collected in 2015 as blood spots on filter paper. The Rotor-Gene Q instrument was utilized to assess the impact of different PCR-HRM reagent mixes and the detection of mixed haplotypes present in the clinical samples. Finally, the prevalence of the wild type (CVMNK) and resistant pfcrt haplotypes (CVIET and SVMNT) was evaluated in this understudied Southwestern region of Uganda. RESULTS The sample source (i.e. Giemsa-stained slides or blood spots) and type of LCGreen-based reagent mixes did not impact the success of PCR-HRM. The detection limit of 10- 5 ng and the ability to identify mixed haplotypes as low as 10 % was similar to other HRM platforms. The CVIET haplotype predominated in the clinical samples (66 %, 162/244); however, there was a large regional variation between the sample groups (94 % CVIET in Group 1 and 44 % CVIET in Group 2). CONCLUSIONS The HRM-based method exhibits the flexibility required to conduct reliable assessment of resistance alleles from various sample types generated during the clinical management of malaria. Large regional variations in CQ resistance haplotypes across Southwestern Uganda emphasizes the need for continued local parasite genotype assessment to inform anti-malarial treatment policies.
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Affiliation(s)
- Kennedy Kassaza
- Epicentre Mbarara Research Centre, Mbarara, Uganda
- Department of Microbiology, Mbarara University of Science and Technology, Mbarara, Uganda
| | - Anna C Long
- Department of Biology, University of Virginia, Box 400328, 22904, Charlottesville, VA, USA
| | - Jennifer M McDaniels
- Department of Biology, University of Virginia, Box 400328, 22904, Charlottesville, VA, USA
| | - Mharlove Andre
- Department of Biology, University of Virginia, Box 400328, 22904, Charlottesville, VA, USA
| | - Wasswa Fredrickson
- Department of Microbiology, Mbarara University of Science and Technology, Mbarara, Uganda
| | | | | | - Darwin J Operario
- Division of Infectious Diseases and International Health, University of Virginia, Charlottesville, VA, 22904, USA
| | - Joel Bazira
- Department of Microbiology, Mbarara University of Science and Technology, Mbarara, Uganda
| | - Juliet A Mwanga-Amumpaire
- Epicentre Mbarara Research Centre, Mbarara, Uganda
- Department of Pediatrics and Child Health, Mbarara University of Science and Technology, Mbarara, Uganda
| | - Christopher C Moore
- Division of Infectious Diseases and International Health, University of Virginia, Charlottesville, VA, 22904, USA
| | - Jennifer L Guler
- Department of Biology, University of Virginia, Box 400328, 22904, Charlottesville, VA, USA.
- Division of Infectious Diseases and International Health, University of Virginia, Charlottesville, VA, 22904, USA.
| | - Yap Boum
- Epicentre Mbarara Research Centre, Mbarara, Uganda.
- Department of Microbiology, Mbarara University of Science and Technology, Mbarara, Uganda.
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Orikiriza P, Nyehangane D, Atwine D, Kisakye JJ, Kassaza K, Amumpaire JM, Boum Y. Evaluation of the SD Bioline TB Ag MPT64 test for identification of Mycobacterium tuberculosis complex from liquid cultures in Southwestern Uganda. Afr J Lab Med 2017; 6:383. [PMID: 28879157 PMCID: PMC5523908 DOI: 10.4102/ajlm.v6i2.383] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Accepted: 05/23/2016] [Indexed: 11/01/2022] Open
Abstract
BACKGROUND To confirm presence of Mycobacterium tuberculosis complex, some tuberculosis culture laboratories still rely on para-nitrobenzoic acid (PNB), a traditional technique that requires sub-culturing of clinical isolates and two to three weeks to give results. Rapid identification tests have improved turnaround times for mycobacterial culture results. Considering the challenges of the PNB method, we assessed the performance of the SD Bioline TB Ag MPT64 assay by using PNB as gold standard to detect M. tuberculosis complex from acid-fast bacilli (AFB) positive cultures. OBJECTIVES The aim of this study was to determine the sensitivity, specificity and turnaround time of the SD MPT64 assay for identification of M. tuberculosis complex, in a setting with high prevalence of tuberculosis and HIV. METHODS A convenience sample of 690 patients, with tuberculosis symptoms, was enrolled at Epicentre Mbarara Research Centre between April 2010 and June 2011. The samples were decontaminated using NALC-NaOH and re-suspended sediments inoculated in Mycobacterium Growth Indicator Tubes (MGIT) media, then incubated at 37 °C for a maximum of eight weeks. A random sample of 50 known negative cultures and 50 non-tuberculous mycobacteria isolates were tested for specificity, while sensitivity was based on AFB positivity. The time required from positive culture to reporting of results was also assessed with PNB used as the gold standard. RESULTS Of the 138 cultures that were AFB-positive, the sensitivity of the SD MPT64 assay was 100.0% [95% CI: 97.3 - 100] and specificity was 100.0% (95% CI, 96.4 - 100). The median time from a specimen receipt to confirmation of strain was 10 days [IQR: 8-12] with SD MPT64 and 24 days [IQR: 22-26] with PNB. CONCLUSION The SD MPT64 assay is comparable to PNB for identification of M. tuberculosis complex and reduces the time to detection.
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Affiliation(s)
- Patrick Orikiriza
- Epicentre Mbarara Research Centre, Mbarara, Uganda.,Department of Microbiology, Faculty of Medicine, Mbarara University of Science and Technology, Mbarara, Uganda
| | | | | | - John J Kisakye
- Department of Biological Sciences, College of Natural Sciences, Makerere University, Kampala, Uganda
| | | | | | - Yap Boum
- Epicentre Mbarara Research Centre, Mbarara, Uganda
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