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1.
Am J Clin Pathol ; 161(1): 89-96, 2024 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-37773021

RESUMEN

OBJECTIVES: Pathology services are limited across most of sub-Saharan Africa. We sought to ascertain the availability of anatomic and clinical pathology services and diagnostic resources in Zambia. METHODS: Two individual surveys-one for anatomic pathology and one for clinical pathology/laboratory medicine-were developed by subject matter experts. These surveys were administered to individuals involved in pathology and laboratory medicine diagnostic services at hospitals and laboratories across Zambia from May to October 2022 using the American Society for Clinical Pathology email listserv. RESULTS: A total of 20 responses were received from 17 unique laboratories-8 sites provide anatomic pathology (AP) services, 12 provide clinical pathology (CP) services, and 3 perform both AP and CP services. Anatomic pathology services are variable and generally limited to a few of the responding laboratories, as only 1 laboratory performs immunohistochemical staining on surgical pathology specimens, and only 2 perform general histochemical stains. Conversely, certain microbiology testing (eg, for HIV) is more widely available. CONCLUSIONS: This study of 17 unique laboratories represents the most complete analysis of pathology capabilities in Zambia. Despite initiatives to improve pathology services, both personnel and infrastructure challenges remain. Given a population of approximately 20 million, expansion of anatomic pathology in Zambia must be prioritized.


Asunto(s)
Servicios de Laboratorio Clínico , Infecciones por VIH , Patología Clínica , Humanos , Zambia , Laboratorios , Hospitales
2.
Bull World Health Organ ; 101(1): 10-19, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36593782

RESUMEN

Objective: To compare the financial and time cost of breast cancer biomarker analysis by immunohistochemistry with that by the Xpert® STRAT4 assay. Methods: We estimated costs (personnel, location, consumables and indirect) and time involved in breast cancer diagnosis at the Butaro Cancer Centre of Excellence, Rwanda, using time-driven activity-based costing. We performed a cost-minimization analysis to compare the cost of biomarker analysis for estrogen receptor, progesterone receptor and human epidermal growth factor receptor-2 status with immunohistochemistry versus STRAT4. We performed sensitivity analyses by altering laboratory-specific parameters for the two methods. Findings: We estimated that breast cancer diagnosis in Rwanda costs 138.29 United States dollars (US$) per patient when conducting biomarker analysis by immunohistochemistry. At a realistic immunohistochemistry antibody utilization efficiency of 70%, biomarker analysis comprises 48.7% (US$ 67.33) of diagnostic costs and takes 33 min. We determined that biomarker analysis with STRAT4 yields a reduction in diagnosis cost of US$ 7.33 (10.9%; 7.33/67.33), and in pathologist and technician time of 20 min (60.6%; 20/33), per patient. Our sensitivity analysis revealed that no cost savings would be made in laboratories with antibody utilization efficiencies over 90%, or where only estrogen and/or progesterone receptor status are assessed; however, such operational efficiencies are unlikely, and more laboratories are pursuing human epidermal growth factor receptor-2 analysis as targeted therapies become increasingly available. Conclusion: Breast cancer biomarker analysis with STRAT4 has the potential to reduce the required human and capital resources in sub-Saharan African laboratories, leading to improved treatment selection and better clinical outcomes.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/genética , Biomarcadores de Tumor/genética , Rwanda , Inmunohistoquímica , Patología Molecular , Estrógenos , ARN Mensajero
3.
Bull. W.H.O. (Online) ; 101(1): 10-19, 2023. figures, tables
Artículo en Inglés | AIM (África) | ID: biblio-1411560

RESUMEN

Objective To compare the financial and time cost of breast cancer biomarker analysis by immunohistochemistry with that by the Xpert® STRAT4 assay. Methods We estimated costs (personnel, location, consumables and indirect) and time involved in breast cancer diagnosis at the Butaro Cancer Centre of Excellence, Rwanda, using time-driven activity-based costing. We performed a cost-minimization analysis to compare the cost of biomarker analysis for estrogen receptor, progesterone receptor and human epidermal growth factor receptor-2 status with immunohistochemistry versus STRAT4. We performed sensitivity analyses by altering laboratory-specific parameters for the two methods. Findings We estimated that breast cancer diagnosis in Rwanda costs 138.29 United States dollars (US$) per patient when conducting biomarker analysis by immunohistochemistry. At a realistic immunohistochemistry antibody utilization efficiency of 70%, biomarker analysis comprises 48.7% (US$ 67.33) of diagnostic costs and takes 33 min. We determined that biomarker analysis with STRAT4 yields a reduction in diagnosis cost of US$ 7.33 (10.9%; 7.33/67.33), and in pathologist and technician time of 20 min (60.6%; 20/33), per patient. Our sensitivity analysis revealed that no cost savings would be made in laboratories with antibody utilization efficiencies over 90%, or where only estrogen and/or progesterone receptor status are assessed; however, such operational efficiencies are unlikely, and more laboratories are pursuing human epidermal growth factor receptor-2 analysis as targeted therapies become increasingly available. Conclusion Breast cancer biomarker analysis with STRAT4 has the potential to reduce the required human and capital resources in subSaharan African laboratories, leading to improved treatment selection and better clinical outcomes.


Asunto(s)
Humanos , Masculino , Femenino , Neoplasias de la Mama , Inmunohistoquímica , Biomarcadores de Tumor , Diagnóstico , ARN Mensajero , Estrógenos , Patología Molecular , Genética
6.
Thorac Surg Clin ; 32(3): 299-306, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35961738

RESUMEN

Pulmonary disease in low- and middle-income countries is highly diverse and dependent on the population, background epidemiology, environmental exposures, and smoking status. Credible evaluation of lung diseases requires skilled clinicians, imaging infrastructure, microbiology, and pathologic diagnostics, including imaging-guided cytology and biopsy. When these tools are available, improvement in patient outcomes is feasible. Pathologic diagnostics of lung lesions, including histology, immunohistochemistry, and molecular testing, are critical to properly stratify patient risk and determine exact therapies for each patient. A critical focus on research and directed interventions in lung cancer treatment specifically is needed to downstage this disease and improve patient outcome.


Asunto(s)
Enfermedades Pulmonares , Neoplasias Pulmonares , Biopsia , Países en Desarrollo , Humanos , Pulmón/diagnóstico por imagen , Pulmón/patología , Enfermedades Pulmonares/diagnóstico , Enfermedades Pulmonares/epidemiología , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/epidemiología , Neoplasias Pulmonares/terapia
7.
Am J Clin Pathol ; 158(3): 318-321, 2022 09 02.
Artículo en Inglés | MEDLINE | ID: mdl-35980838
8.
J Infect Dis ; 226(8): 1470-1479, 2022 10 17.
Artículo en Inglés | MEDLINE | ID: mdl-35556124

RESUMEN

BACKGROUND: Cerebral malaria (CM) is a rare, but severe and frequently fatal outcome of infection with Plasmodium falciparum. Pathogenetic mechanisms include endothelial activation and sequestration of parasitized erythrocytes in the cerebral microvessels. Increased concentrations of glycosaminoglycans in urine and plasma of malaria patients have been described, suggesting involvement of endothelial glycocalyx. METHODS: We used lectin histochemistry on postmortem samples to compare the distribution of multiple sugar epitopes on cerebral capillaries in children who died from CM and from nonmalarial comas. RESULTS: N-acetyl glucosamine residues detected by tomato lectin are generally reduced in children with CM compared to controls. We used the vascular expression of intercellular adhesion molecule 1 and mannose residues on brain capillaries of CM as evidence of local vascular inflammation, and both were expressed more highly in CM patients than controls. Sialic acid residues were found to be significantly reduced in patients with CM. By contrast, the levels of other sugar epitopes regularly detected on the cerebral vasculature were unchanged, and this suggests specific remodeling of cerebral microvessels in CM patients. CONCLUSIONS: Our findings support and expand upon earlier reports of disruptions of the endothelial glycocalyx in children with severe malaria.


Asunto(s)
Malaria Cerebral , Malaria Falciparum , Encéfalo/patología , Capilares/patología , Niño , Epítopos/metabolismo , Eritrocitos/metabolismo , Glucosamina/metabolismo , Glicocálix/metabolismo , Glicosaminoglicanos/metabolismo , Humanos , Molécula 1 de Adhesión Intercelular/metabolismo , Lectinas , Malaria Cerebral/metabolismo , Manosa/metabolismo , Ácido N-Acetilneuramínico/metabolismo , Plasmodium falciparum/fisiología
9.
J Infect Dis ; 225(6): 1070-1080, 2022 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-32845969

RESUMEN

BACKGROUND: In cerebral malaria, the retina can be used to understand disease pathogenesis. The mechanisms linking sequestration, brain swelling, and death remain poorly understood. We hypothesized that retinal vascular leakage would be associated with brain swelling. METHODS: We used retinal angiography to study blood-retinal barrier integrity. We analyzed retinal leakage, histopathology, brain magnatic resonance imaging (MRI), and associations with death and neurological disability in prospective cohorts of Malawian children with cerebral malaria. RESULTS: Three types of retinal leakage were seen: large focal leak (LFL), punctate leak (PL), and vessel leak. The LFL and PL were associated with death (odds ratio [OR] = 13.20, 95% confidence interval [CI] = 5.21-33.78 and OR = 8.58, 95% CI = 2.56-29.08, respectively) and brain swelling (P < .05). Vessel leak and macular nonperfusion were associated with neurological disability (OR = 3.71, 95% CI = 1.26-11.02 and OR = 9.06, 95% CI = 1.79-45.90). Large focal leak was observed as an evolving retinal hemorrhage. A core of fibrinogen and monocytes was found in 39 (93%) white-centered hemorrhages. CONCLUSIONS: Blood-retina barrier breakdown occurs in 3 patterns in cerebral malaria. Associations between LFL, brain swelling, and death suggest that the rapid accumulation of cerebral hemorrhages, with accompanying fluid egress, may cause fatal brain swelling. Vessel leak, from barrier dysfunction, and nonperfusion were not associated with severe brain swelling but with neurological deficits, suggesting hypoxic injury in survivors.


Asunto(s)
Edema Encefálico , Malaria Cerebral , Barrera Hematorretinal/patología , Edema Encefálico/complicaciones , Edema Encefálico/patología , Niño , Humanos , Malaria Cerebral/complicaciones , Estudios Prospectivos , Retina/patología
10.
Am J Clin Pathol ; 157(2): 279-285, 2022 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-34542557

RESUMEN

OBJECTIVES: In response to requests for training in cancer pathology, two virtual training courses were organized: one in English for participants in Nigeria and another in French for participants in Francophone Africa. Each course had weekly 90-minute sessions covering essential topics in cancer pathology led by global experts. METHODS: Two research questions were investigated for both courses: (1) did the participants improve their knowledge of the topics covered during the course, and (2) did the course participants appreciate the virtual training format? RESULTS: The Nigeria course enrolled 85 participants from 26 Nigerian states; the Francophone Africa course enrolled 425 participants from 18 African countries. In the pre-post technical assessment, participants increased their scores on average by 3.4% (P > .05) in the Nigeria course and by 13.1% (P < .001) in the Francophone Africa course. On the postcourse survey, 95.8% of Nigerian respondents and 96.1% of Francophone African respondents reported being satisfied or very satisfied with the virtual format. CONCLUSIONS: Virtual training is a promising tool to improve cancer diagnosis in Africa, as the experience of the courses illustrates that participants appreciate the virtual format. Continued training is required to reinforce skills and enable participants to appropriately apply new knowledge to their daily practice.


Asunto(s)
Neoplasias , África , Humanos , Neoplasias/diagnóstico , Encuestas y Cuestionarios
11.
JCO Glob Oncol ; 7: 917-924, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34129368

RESUMEN

Diagnostic pathology services for oncology health systems are essential; yet, surveys, observations, and hard data from across low- and middle-income countries have revealed that these services are almost always lacking adequate quality and often missing completely. The City Cancer Challenge Foundation (C/Can), the American Society for Clinical Pathology, and C/Can partner cities undertook intense analysis of their existing pathology services as part of a year-long assessment process including the specific formation of a pathology-focused team. Internal and external expert assessments identified sustainable solutions adapted to the local context and level of resources and created specific local implementation projects. Through local leadership, capacity development, and collaboration, services were improved city-wide in three cities: Cali, Colombia; Asunción, Paraguay; and Yangon, Myanmar. Common problems identified across cities included deficiencies in personnel training, equipment, reagents, processes, quality, and coordination. Specific solutions included quality training, standard process development and regulation, implementation of new services, and public-private collaboration. As the first cities joining the C/Can initiative, Cali, Asunción, and Yangon demonstrate the success of the approach and the value of local expertise in identifying problems and solutions. The additional value of international partners' expertise created opportunities for growth through mentorship and technical support. Importantly, the power of healthcare programs with strong political support is emphasized.


Asunto(s)
Países en Desarrollo , Neoplasias , Ciudades , Colombia , Mianmar , Neoplasias/terapia , Paraguay , Estados Unidos
12.
Am J Clin Pathol ; 156(5): 766-776, 2021 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-34050358

RESUMEN

OBJECTIVES: Breast cancer immunohistochemistry (IHC) biomarker testing is limited in low-resource settings, and an alternative solution is needed. A point-of-care mRNA STRAT4 breast cancer assay for ESR1, PGR, ERBB2, and MKi67, for use on the GeneXpert platform, has been recently validated on tissues from internationally accredited laboratories, showing excellent concordance with IHC. METHODS: We evaluated STRAT4/IHC ESR1/estrogen receptor (ER), ERBB2/human epidermal growth factor receptor 2 (HER2) concordance rates of 150 breast cancer tissues processed in Rwanda, with undocumented cold ischemic and fixation time. RESULTS: Assay fail/indeterminate rate was 2.6% for ESR1 and ERBB2. STRAT4 agreement with ER IHC was 92.5% to 93.3% and 97.8% for HER2, for standard (1x) and concentrated (4x) reagent-conserving protocols, respectively. Eleven of 12 discordant ER/ESR1 cases were ESR1- negative/IHC-positive. These had low expression of ER by IHC in mostly very small tumor areas tested (7/12; <25 mm2). In two of three discordant HER2 cases, the STRAT4-ERBB2 result correlated with the subsequent fluorescence in situ hybridization (FISH) result. STRAT4-ERBB2 results in 9 of 10 HER2-IHC equivocal cases were concordant with FISH. CONCLUSIONS: The STRAT4 assay is an alternative for providing quality-controlled breast cancer biomarker data in laboratories unable to provide quality and/or cost-efficient IHC services.


Asunto(s)
Biomarcadores de Tumor/análisis , Neoplasias de la Mama/diagnóstico , Reacción en Cadena de la Polimerasa Multiplex/métodos , ARN Mensajero/análisis , Países en Desarrollo , Femenino , Humanos , Rwanda
13.
JCO Glob Oncol ; 7: 153-161, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33493021

RESUMEN

PURPOSE: At the 12th meeting of AORTIC (African Organization for Research and Training in Cancer) in Maputo, Mozambique, held between November 5 and November 8, 2019, a special workshop was organized to focus on the need for collaboration and coordination between governments and health systems in Africa with academic, industry, association, and other nongovernmental organizations to effect sustainable positive change for the care of patients with cancer. METHODS: Representatives from seven different projects in Africa presented implementation science and demonstration projects of their to date efforts in cancer system improvement including patient access, South-South partnerships, in-country specialized training, palliative care consortium, treatment outcomes, and focused pathology and diagnostic capacity building. Key partners of the various projects served as moderators and commentators during the session. RESULTS: From across all the presentations, lessons learned and exemplary evidence of the value of partnerships were gathered and summarized. CONCLUSION: The concluding synthesis of the presentations determined that with the broad needs across cancer requiring in-depth expertise at each point on a patient's journey, no single organization can effect change alone. Multipartner collaborations not only should be the norm but should also be coordinated so that efforts are not duplicated and maximum patient access to cancer diagnosis and care is achieved.


Asunto(s)
Creación de Capacidad , Organizaciones , África , Humanos , Mozambique
14.
Am J Clin Pathol ; 155(4): 473-478, 2021 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-33009558

RESUMEN

OBJECTIVES: We developed and participated in a 1-week laboratory medicine training presented from June 3, 2019, to June 7, 2019. METHODS: The training was a combination of daily morning lectures and case presentations as well as afternoon practical sessions in the clinical laboratory. The content was selected over months by local organizers and the visiting faculty and further modified on site to reflect local needs. RESULTS: Participants identified practice changes that could be realized in the short term but most faced significant barriers to implementation in the absence of structured and long-term follow-up. CONCLUSIONS: In this report, we review insights learned from our experience and reflect on strategies for realistic, meaningful, and relevant contributions in the setting of laboratory medicine-oriented short-term programs.


Asunto(s)
Laboratorios , Patología/educación , Países en Desarrollo , Humanos , Sierra Leona
15.
Am J Clin Pathol ; 153(3): 374-379, 2020 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-31755908

RESUMEN

OBJECTIVES: This study assessed the prevalence, general interest, and barriers to implementing global health curricula in pathology residency programs. METHODS: We conducted a survey of 166 US pathology residency programs. RESULTS: Thirty-two (195) of 166 programs responded. Of these, 13% have a formalized global health program (n = 4), and the majority indicated at least some general interest in global health among trainees (88%, n = 28) and faculty (94%, n = 30), albeit at a low to moderate level. Funding limitations, regulatory constraints, and insufficient knowledge of global health were frequently cited barriers to developing a global health program. CONCLUSIONS: Few US pathology departments incorporate global health education into postgraduate training. The importance of pathology in global health has been underappreciated, despite its critical role in the delivery of health care in resource-limited settings. One solution is for pathology departments to expand global health educational opportunities for trainees.


Asunto(s)
Curriculum , Salud Global/educación , Patología/educación , Educación de Postgrado en Medicina , Humanos , Internado y Residencia , Estados Unidos
17.
Mol Cell Proteomics ; 17(1): 43-60, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29162636

RESUMEN

Despite recent efforts toward control and elimination, malaria remains a major public health problem worldwide. Plasmodium falciparum resistance against artemisinin, used in front line combination drugs, is on the rise, and the only approved vaccine shows limited efficacy. Combinations of novel and tailored drug and vaccine interventions are required to maintain the momentum of the current malaria elimination program. Current evidence suggests that strain-transcendent protection against malaria infection can be achieved using whole organism vaccination or with a polyvalent vaccine covering multiple antigens or epitopes. These approaches have been successfully applied to the human-infective sporozoite stage. Both systemic and tissue-specific pathology during infection with the human malaria parasite P. falciparum is caused by asexual blood stages. Tissue tropism and vascular sequestration are the result of specific binding interactions between antigens on the parasite-infected red blood cell (pRBC) surface and endothelial receptors. The major surface antigen and parasite ligand binding to endothelial receptors, PfEMP1 is encoded by about 60 variants per genome and shows high sequence diversity across strains. Apart from PfEMP1 and three additional variant surface antigen families RIFIN, STEVOR, and SURFIN, systematic analysis of the infected red blood cell surface is lacking. Here we present the most comprehensive proteomic investigation of the parasitized red blood cell surface so far. Apart from the known variant surface antigens, we identified a set of putative single copy surface antigens with low sequence diversity, several of which are validated in a series of complementary experiments. Further functional and immunological investigation is underway to test these novel P. falciparum blood stage proteins as possible vaccine candidates.


Asunto(s)
Antígenos de Protozoos/inmunología , Antígenos de Superficie/inmunología , Vacunas contra la Malaria , Plasmodium falciparum/inmunología , Animales , Membrana Celular/inmunología , Eritrocitos/inmunología , Femenino , Ratones Endogámicos BALB C , Proteoma , Proteómica
19.
Nat Microbiol ; 1(7): 16079, 2016 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-27572973

RESUMEN

Human babesiosis caused by Babesia microti is an emerging tick-borne zoonosis of increasing importance due to its rising incidence and expanding geographic range(1). Infection with this organism, an intraerythrocytic parasite of the phylum Apicomplexa, causes a febrile syndrome similar to malaria(2). Relapsing disease is common among immunocompromised and asplenic individuals(3,4) and drug resistance has recently been reported(5). To investigate the origin and genetic diversity of this parasite, we sequenced the complete genomes of 42 B. microti samples from around the world, including deep coverage of clinical infections at endemic sites in the continental USA. Samples from the continental USA segregate into a Northeast lineage and a Midwest lineage, with subsequent divergence of subpopulations along geographic lines. We identify parasite variants that associate with relapsing disease, including amino acid substitutions in the atovaquone-binding regions of cytochrome b (cytb) and the azithromycin-binding region of ribosomal protein subunit L4 (rpl4). Our results shed light on the origin, diversity and evolution of B. microti, suggest possible mechanisms for clinical relapse, and create the foundation for further research on this emerging pathogen.


Asunto(s)
Babesia microti/genética , Babesiosis/parasitología , Variación Genética , Genoma de Protozoos , Sustitución de Aminoácidos , Animales , Atovacuona/metabolismo , Azitromicina/metabolismo , Babesiosis/epidemiología , Citocromos b/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Unión Proteica , Recurrencia , Proteínas Ribosómicas/metabolismo , Estados Unidos/epidemiología , Zoonosis
20.
J Pathol ; 235(2): 253-65, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25294240

RESUMEN

The identification of poliovirus receptor-like 4 (PVRL4) as the second natural receptor for measles virus (MV) has closed a major gap in our understanding of measles pathogenesis, and explains how this predominantly lymphotropic virus breaks through epithelial barriers to transmit to a susceptible host. Advances in the development of wild-type, recombinant MVs which express fluorescent proteins making infected cells readily detectable in living tissues and animals, has also increased our understanding of this important and highly transmissible human disease. Thus, it is timely to review how these advances have provided new insights into MV infection of immune, epithelial and neural cells. This demands access to primate samples that help us understand the early and acute stages of the disease, which are challenging to dissect due to the mild/self-limiting nature of the infection. It also requires well-characterized and rather rare human tissue samples from patients who succumb to neurological sequelae to help study the consequences of the long-term persistence of this RNA virus in vivo. Collectively, these studies have provided unique insights into how the use of two cellular receptors, CD150 and PVRL4, governs the in vivo tissue-specific temporal patterns of virus spread and resulting pathological lesions. Analysis of tissue samples has also demonstrated the importance of differing mechanisms of virus cell-to-cell spread within lymphoid, epithelial and neural tissues in the dissemination of MV during acute and long-term persistent infections. Given the incentive to eradicate MV globally, and the inevitable question as to whether or not vaccination should cease in light of the existence of closely related morbilliviruses, a thorough understanding of measles pathological lesions is essential.


Asunto(s)
Virus del Sarampión/patogenicidad , Sarampión/patología , Sarampión/virología , Animales , Modelos Animales de Enfermedad , Genotipo , Interacciones Huésped-Patógeno , Humanos , Sarampión/inmunología , Sarampión/prevención & control , Sarampión/transmisión , Vacuna Antisarampión/uso terapéutico , Virus del Sarampión/genética , Virus del Sarampión/inmunología , Patología Molecular/métodos , Valor Predictivo de las Pruebas , Tropismo Viral , Virología/métodos , Virulencia
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