Background: The diagnosis of tuberculosis (TB) in resource-limited settings relies on Ziehl-Neelsen (ZN) smear microscopy. LED fluorescence microscopy (LED-FM) has many potential advantages over ZN smear microscopy, but requires evaluation in the field. The aim of this study was to assess the sensitivity/specificity of LED-FM for the diagnosis of pulmonary TB and whether its performance varies with the timing of specimen collection.
Methods And Findings: Adults with cough ≥2 wk were enrolled consecutively in Ethiopia, Nepal, Nigeria, and Yemen. Sputum specimens were examined by ZN smear microscopy and LED-FM and compared with culture as the reference standard. Specimens were collected using a spot-morning-spot (SMS) or spot-spot-morning (SSM) scheme to explore whether the collection of the first two smears at the health care facility (i.e., "on the spot") the first day of consultation followed by a morning sample the next day (SSM) would identify similar numbers of smear-positive patients as smears collected via the SMS scheme (i.e., one on-the-spot-smear the first day, followed by a morning specimen collected at home and a second on-the-spot sample the second day). In total, 529 (21.6%) culture-positive and 1,826 (74.6%) culture-negative patients were enrolled, of which 1,156 (49%) submitted SSM specimens and 1,199 (51%) submitted SMS specimens. Single LED-FM smears had higher sensitivity but lower specificity than single ZN smears. Using two LED-FM or two ZN smears per patient was 72.8% (385/529, 95% CI 68.8%-76.5%) and 65.8% (348/529, 95% CI 61.6%-69.8%) sensitive (p<0.001) and 90.9% (1,660/1,826, 95% CI 89.5%-92.2%) and 98% (1,790/1,826, 95% CI 97.3%-98.6%) specific (p<0.001). Using three LED-FM or three ZN smears per patient was 77% (408/529, 95% CI 73.3%-80.6%) and 70.5% (373/529, 95% CI 66.4%-74.4%, p<0.001) sensitive and 88.1% (95% CI 86.5%-89.6%) and 96.5% (95% CI 96.8%-98.2%, p<0.001) specific. The sensitivity/specificity of ZN smear microscopy and LED-FM did not vary between SMS and SSM.
Conclusions: LED-FM had higher sensitivity but, in this study, lower specificity than ZN smear microscopy for diagnosis of pulmonary TB. Performance was independent of the scheme used for collecting specimens. The introduction of LED-FM needs to be accompanied by appropriate training, quality management, and monitoring of performance in the field.
Trial Registration: Current Controlled Trials ISRCTN53339491. Please see later in the article for the Editors' Summary.
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http://dx.doi.org/10.1371/journal.pmed.1001057 | DOI Listing |
PLoS One
December 2024
Department of Endodontics, School of Health and Biosciences, Pontifical Catholic University of Paraná -PUC/PR, Curitiba, Paraná, Brazil.
Aim: This study evaluated the smear layer removal provided by conventional, sonic, and ultrasonic irrigation techniques.
Methodology: Forty extracted human mandibular first premolars were selected and instrumented using the ProTaper Next System files and 2.5% sodium hypochlorite.
In a febrile patient admitted to the Adult Emergency Department, the haematology analyser detected the presence of erythrocytes infected with plasmodia. The finding was confirmed by thin smear and thick drop microscopy. A 43-year-old male patient was admitted to the Emergency Department with fever, vomiting, diarrhoea and pain in the upper abdomen.
View Article and Find Full Text PDFTissue Cell
December 2024
Department of Electronics and Computer Engineering, Faculty of Electrical Engineering, Universiti Teknologi Malaysia, Johor Bahru, Johor 81310 UTM, Malaysia.
Malaria is endemic in poverty-stricken regions of the world, and most diagnosis reveal comorbidity with other infectious diseases some of which manifest as a deformity of the structural arrangement of the Red Blood Cells (RBCs) during thin blood smear microscopy. This common occurring deformity is termed rouleaux formation, and it is the stacking together of RBCs like chains of coins. The presence of rouleaux formation indicates either a bacterial infection, connective tissue disease, chronic liver disease, multiple myeloma or diabetes among others, it is a highly common occurrence in malaria infected patients and according to the international council for standardization of hematology (ICSH), microscopists are mandated to report its presence.
View Article and Find Full Text PDFBMC Infect Dis
December 2024
Department of Internal Medicine, Asokoro District Hospital, Abuja, Nigeria.
Background: Tuberculosis (TB), caused by Mycobacterium tuberculosis, is a leading cause of infection-related deaths worldwide. Children with underdeveloped immune systems are particularly vulnerable, experiencing symptoms akin to common childhood illnesses. Early diagnosis and treatment typically yield positive outcomes.
View Article and Find Full Text PDFMalar J
December 2024
Department of Medical Parasitology, School of Biomedical and Laboratory Sciences, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia.
Background: Malaria poses a significant public health threat globally, particularly in African regions, where asymptomatic malaria is a considerable logistic problem. Individuals with asymptomatic malaria do not seek treatment, and thus they are invisible to health facilities and represent a substantial hidden reservoir of Plasmodium species. This study aimed to determine the prevalence of asymptomatic malaria and its associated factors in Gorgora, western Dembia district, Northwest Ethiopia.
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