Evidence map›Paper›PMID 31039160›Full record

ArticlePloS one2019

Optimising fluorescein diacetate sputum smear microscopy for assessing patients with pulmonary tuberculosis.

Sumona Datta, Keren Alvarado, Robert H Gilman, Teresa Valencia, Christian Aparicio, Eric S Ramos, Rosario Montoya, Carlton A Evans

Open access · goldAbstract read
In one paragraph

Article in PloS one, 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.

0numbers the graph read from it
0cells of the map it votes in
2citing papers in PubMed
0.3field-weighted citation impact, top 43% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

2 citing papers in PubMed, 4 citations in OpenAlex.

  1. Article
  2. Differential Culturability ofFrontiers in microbiology · 2019
    Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

8 authors at 2 institutions in 3 countries.

Sumona DattaInfectious Diseases & Immunity, Wellcome Trust Centre for Global Health Research, Imperial College London, United Kingdom.ORCID 0000-0002-3476-9753
Keren AlvaradoIFHAD: Innovation For Health And Development, Laboratory of research and development, Universidad Peruana Cayetano Heredia, Lima, Peru.
Robert H GilmanDepartment of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States of America.
Teresa ValenciaIFHAD: Innovation For Health And Development, Laboratory of research and development, Universidad Peruana Cayetano Heredia, Lima, Peru.
Christian AparicioIFHAD: Innovation For Health And Development, Laboratory of research and development, Universidad Peruana Cayetano Heredia, Lima, Peru.
Eric S RamosIFHAD: Innovation For Health And Development, Laboratory of research and development, Universidad Peruana Cayetano Heredia, Lima, Peru.
Rosario MontoyaIFHAD: Innovation For Health And Development, Laboratory of research and development, Universidad Peruana Cayetano Heredia, Lima, Peru.
Carlton A EvansInfectious Diseases & Immunity, Wellcome Trust Centre for Global Health Research, Imperial College London, United Kingdom.
Universidad Peruana Cayetano Heredia · PEJohns Hopkins University · US

Funding

Medical Research Council MR/K007467/1Wellcome Trust 057434/Z/99/ZWellcome Trust 070005/Z/02/ZWellcome Trust 078340/Z/05/ZWellcome Trust 105788/Z/14/ZWellcome Trust 201251/Z/16/Z
6 · The paper itself

Abstract

backgroundAssessing Mycobacterium tuberculosis (TB) viability by fluorescein diacetate (FDA) microscopy can predict TB culture results, treatment response and infectiousness. However, diverse methods have been published. We aimed to optimise FDA microscopy, minimising sputum processing, biohazard and complexity for use in resource-constrained settings. METHODS AND

resultsOptimization: Patients with smear-positive pulmonary TB before treatment and healthy control participants provided sputa. These were divided into equal aliquots that were tested directly or after NaOH centrifuge-decontamination. Each aliquot was cultured and used to prepare slides (n = 80). FDA microscopy used: 1 or 3 drops of sputum; with/out acid-alcohol wash; with/out phenol sterilization; with 0/30/60 seconds KMnO4 quenching. Control samples all had negative culture and microscopy results. FDA microscopy had higher sensitivity when performed directly (without centrifuge-decontamination) on 1 drop of sputum (P<0.001), because 3 drops obscured microscopy. Acid-alcohol wash and KMnO4 quenching made bacilli easier to identity (P = 0.005). Phenol sterilization did not impair microscopy (P>0.1). Validation: The 2 protocols that performed best in the optimization experiments were reassessed operationally by comparing duplicate slides (n = 412) stained with KMnO4 quenching for 30 versus 60 seconds. FDA microscopy results were similar (P = 0.4) and highly reproducible, with 97% of counts agreeing within +/-1 logarithm. Storage: Smear microscopy slides and aliquots of the sputum from which they were made were stored for 4 weeks. Twice-weekly, paired slides (n = 80) were stained with freshly prepared versus stored FDA and read quantitatively. Storing sputum, microscopy slides or FDA solution at 4°C or room temperature had no effect on FDA microscopy results (all P>0.2). Cost: Material costs for each slide tested by FDA microscopy using reagents purchased locally were USD $0.05 and required the same equipment, time and skills as auramine acid-fast microscopy.

conclusionsWe recommend a simple, bio-secure protocol for FDA microscopy that provides sensitive and repeatable results without requiring centrifugation.

Indexed as

AdultDiagnostic Tests, RoutineFemaleFluoresceinHumansMicroscopyMycobacterium tuberculosisSputumTuberculosis, PulmonaryFluorescein

Identifiers

PMID31039160
PMCPMC6490897
OpenAlexW2943160378

What OpenQuestion holds

Textmetadata
LicenceCC BY
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Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.