RESUMO
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.
Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Biomarcadores Tumorais/genética , Ruanda , Imuno-Histoquímica , Patologia Molecular , Estrogênios , RNA MensageiroRESUMO
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.
Assuntos
Malária Cerebral , Malária Falciparum , Encéfalo/patologia , Capilares/patologia , Criança , Epitopos/metabolismo , Eritrócitos/metabolismo , Glucosamina/metabolismo , Glicocálix/metabolismo , Glicosaminoglicanos/metabolismo , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Lectinas , Malária Cerebral/metabolismo , Manose/metabolismo , Ácido N-Acetilneuramínico/metabolismo , Plasmodium falciparum/fisiologiaRESUMO
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 (Pâ <â .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.
Assuntos
Edema Encefálico , Malária Cerebral , Barreira Hematorretiniana/patologia , Edema Encefálico/complicações , Edema Encefálico/patologia , Criança , Humanos , Malária Cerebral/complicações , Estudos Prospectivos , Retina/patologiaRESUMO
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.
Assuntos
Antígenos de Protozoários/imunologia , Antígenos de Superfície/imunologia , Vacinas Antimaláricas , Plasmodium falciparum/imunologia , Animais , Membrana Celular/imunologia , Eritrócitos/imunologia , Feminino , Camundongos Endogâmicos BALB C , Proteoma , ProteômicaRESUMO
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.
Assuntos
Vírus do Sarampo/patogenicidade , Sarampo/patologia , Sarampo/virologia , Animais , Modelos Animais de Doenças , Genótipo , Interações Hospedeiro-Patógeno , Humanos , Sarampo/imunologia , Sarampo/prevenção & controle , Sarampo/transmissão , Vacina contra Sarampo/uso terapêutico , Vírus do Sarampo/genética , Vírus do Sarampo/imunologia , Patologia Molecular/métodos , Valor Preditivo dos Testes , Tropismo Viral , Virologia/métodos , VirulênciaRESUMO
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.
Assuntos
Serviços de Laboratório Clínico , Infecções por HIV , Patologia Clínica , Humanos , Zâmbia , Laboratórios , HospitaisRESUMO
We examined the brains of 50 Malawian children who satisfied the clinical definition of cerebral malaria (CM) during life; 37 children had sequestration of infected red blood cells (iRBCs) and no other cause of death, and 13 had a nonmalarial cause of death with no cerebral sequestration. For comparison, 18 patients with coma and no parasitemia were included. We subdivided the 37 CM cases into two groups based on the cerebral microvasculature pathology: iRBC sequestration only (CM1) or sequestration with intravascular and perivascular pathology (CM2). We characterized and quantified the axonal and myelin damage, blood-brain barrier (BBB) disruption, and cellular immune responses and correlated these changes with iRBC sequestration and microvascular pathology. Axonal and myelin damage was associated with ring hemorrhages and vascular thrombosis in the cerebral and cerebellar white matter and brainstem of the CM2 cases. Diffuse axonal and myelin damage were present in CM1 and CM2 cases in areas of prominent iRBC sequestration. Disruption of the BBB was associated with ring hemorrhages and vascular thrombosis in CM2 cases and with sequestration in both CM1 and CM2 groups. Monocytes with phagocytosed hemozoin accumulated within microvessels containing iRBCs in CM2 cases but were not present in the adjacent neuropil. These findings are consistent with a link between iRBC sequestration and intravascular and perivascular pathology in fatal pediatric CM, resulting in myelin damage, axonal injury, and breakdown of the BBB.
Assuntos
Barreira Hematoencefálica/patologia , Malária Cerebral/patologia , Encéfalo/patologia , Pré-Escolar , Eritrócitos/microbiologia , Eritrócitos/patologia , Feminino , Humanos , Malária Cerebral/mortalidade , Malaui , MasculinoRESUMO
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.
Assuntos
Pneumopatias , Neoplasias Pulmonares , Biópsia , Países em Desenvolvimento , Humanos , Pulmão/diagnóstico por imagem , Pulmão/patologia , Pneumopatias/diagnóstico , Pneumopatias/epidemiologia , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/terapiaRESUMO
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% (Pâ >â .05) in the Nigeria course and by 13.1% (Pâ <â .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.
Assuntos
Neoplasias , África , Humanos , Neoplasias/diagnóstico , Inquéritos e QuestionáriosRESUMO
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.
Assuntos
Laboratórios , Patologia/educação , Países em Desenvolvimento , Humanos , Serra LeoaRESUMO
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.
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Biomarcadores Tumorais/análise , Neoplasias da Mama/diagnóstico , Reação em Cadeia da Polimerase Multiplex/métodos , RNA Mensageiro/análise , Países em Desenvolvimento , Feminino , Humanos , RuandaRESUMO
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.
Assuntos
Países em Desenvolvimento , Neoplasias , Cidades , Colômbia , Mianmar , Neoplasias/terapia , Paraguai , Estados UnidosRESUMO
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.
Assuntos
Fortalecimento Institucional , Organizações , África , Humanos , MoçambiqueRESUMO
Infections with rare pathogens are being recognized with increasing frequency in severely immunocompromised patients. As a result of these patients' underlying compromised defenses and susceptibility to atypical organisms, tissue biopsies from patients within this population may demonstrate nonclassical histopathological findings. Here, we describe an unusual granulomatous reaction to gram-positive cocci in the skin of a 52-year-old man undergoing salvage chemotherapy for acute myeloid leukemia. The patient presented with a papular eruption on the arms, trunk, and face and fever; concomitant blood cultures were positive for Rothia mucilaginosa and Streptococcus salivarius. Histologic evaluation revealed a granulomatous dermatitis associated with numerous small, round, predominantly intracellular bacteria. Classically, cutaneous infiltrates associated with coccoid bacterial infections are suppurative and not granulomatous. The intracellular organisms stained positive for Gram, periodic acid-Schiff, and Grocott methenamine silver stains, suggestive of R. mucilaginosa. Rothia mucilaginosa, a component of the oral flora, was first reported as a human pathogen in 1978. Although the majority of cases in the literature have described R. mucilaginosa bacteremia, other reported manifestations include meningitis, endocarditis, pneumonia, osteomyelitis, and peritonitis. To our knowledge, however, only 1 prior report has described a cutaneous manifestation of R. mucilaginosa septicemia, which occurred in a patient with neutropenia. This is the second reported case of an infectious granulomatous dermatitis associated with R. mucilaginosa bacteremia and raises awareness of this unusual histopathological presentation in the setting of a bacterial infection affecting the skin.
Assuntos
Bacteriemia/complicações , Dermatite/diagnóstico , Dermatite/microbiologia , Micrococcaceae/patogenicidade , Infecções por Actinomycetales/complicações , Infecções por Actinomycetales/microbiologia , Bacteriemia/microbiologia , Biópsia , Tratamento Farmacológico , Humanos , Hospedeiro Imunocomprometido , Leucemia Mieloide Aguda/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Infecções Oportunistas/complicações , Infecções Oportunistas/microbiologia , Pele/microbiologia , Pele/patologiaRESUMO
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.
Assuntos
Currículo , Saúde Global/educação , Patologia/educação , Educação de Pós-Graduação em Medicina , Humanos , Internato e Residência , Estados UnidosAssuntos
Modelos Animais de Doenças , Malária Cerebral/patologia , Plasmodium berghei/patogenicidade , Animais , Congressos como Assunto , Eritrócitos/parasitologia , Humanos , Malária Cerebral/parasitologia , Camundongos , Plasmodium falciparum/patogenicidade , Plasmodium knowlesi/patogenicidade , Plasmodium vivax/patogenicidade , PrimatasRESUMO
Mycobacterial infections of the skin classically cause a granulomatous tissue reaction. We have observed a suppurative pattern of inflammation associated with infections by rapid-growing Mycobacterium species in immunocompromised patients. We report 6 cases in skin and soft tissue with an unusual but consistent lack of a predominance of granulomatous inflammation. Of the 6 cases, 4 had predominantly (approximately 75%) suppurative inflammation, 1 case predominantly demonstrated (approximately 75%) a mix of acute and chronic inflammation, and 1 case showed an approximately equal contribution of suppurative and granulomatous inflammation. All 6 cases showed abscess formation and numerous acid-fast bacilli (AFB) on AFB stain and were confirmed by tissue culture. Of these 6 cases, 2 had microabscesses with central pseudocysts harboring microorganisms. Five patients were taking oral prednisone, and 1 had an uncharacterized immunodeficiency. These cases highlight the need for awareness of this unusual manifestation of infection with rapid-growing Mycobacterium species, particularly in immunocompromised patients.