Evidence map›Paper›PMID 34386778›Full record

ArticleOsteoarthritis and cartilage open2021

Calcium pyrophosphate crystal size and characteristics.

Monica Zell, Thanda Aung, Marian Kaldas, Ann K Rosenthal, Bijie Bai, Tairan Liu, Aydogan Ozcan, John D FitzGerald

Open access · goldAbstract read
In one paragraph

Article in Osteoarthritis and cartilage open, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 5 papers.

0numbers the graph read from it
0cells of the map it votes in
5citing papers in PubMed
2.0field-weighted citation impact, top 17% 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

5 citing papers in PubMed, 12 citations in OpenAlex.

  1. Article
  2. Article
  3. Article
  4. Review
  5. Pseudogout of the lumbar spine.Radiology case reports · 2023
    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 3 institutions in 1 country.

Monica ZellDepartment of Medicine, David Geffen School of Medicine, UCLA Medical Center, USA.
Thanda AungDivision of Rheumatology, Department of Medicine, David Geffen School of Medicine, UCLA Medical Center, USA.
Marian KaldasDivision of Rheumatology, Department of Medicine, David Geffen School of Medicine, UCLA Medical Center, USA.
Ann K RosenthalDivision of Rheumatology, Department of Medicine, Medical College of Wisconsin, USA.
Bijie BaiDepartment of Electrical and Computer Engineering, University of California Los Angeles, USA.
Tairan LiuDepartment of Electrical and Computer Engineering, University of California Los Angeles, USA.
Aydogan OzcanDepartment of Electrical and Computer Engineering, University of California Los Angeles, USA.
John D FitzGeraldDivision of Rheumatology, Department of Medicine, David Geffen School of Medicine, UCLA Medical Center, USA.
Olive View-UCLA Medical Center · USCalifornia NanoSystems Institute · USMedical College of Wisconsin · US

Funding

Development and validation of lens-free polarized microscopy to identify mono-sodium urate and calcium pyrophosphate crystals from synovial fluidR21AR072946 · NIAMS · UNIVERSITY OF CALIFORNIA LOS ANGELES · PI FITZGERALD, JOHN D, OZCAN, AYDOGAN · 2018 to 2019
$375k
Mutations in Osteoprotegerin Cause Calcium Pyrophosphate Deposition DiseaseI01BX004454 · VA · CLEMENT J. ZABLOCKI VA MEDICAL CENTER · PI ROSENTHAL, ANN K · 2019 to 2025
–
BLRD VA I01 BX004454NIAMS NIH HHS R21 AR072946
6 · The paper itself

Abstract

objectiveTo describe the characteristics of calcium pyrophosphate (CPP) crystal size and morphology under compensated polarized light microscopy (CPLM). Secondarily, to describe CPP crystals seen only with digital enhancement of CPLM images, confirmed with advanced imaging techniques.

methodsClinical lab-identified CPP-positive synovial fluid samples were collected from 16 joint aspirates. Four raters used a standardized protocol to describe crystal shape, birefringence strength and color. A crystal expert confirmed CPLM-visualized crystal identification. For crystal measurement, a high-pass linear light filter was used to enhance resolution and line discrimination of digital images. This process identified additional

resultsOf 932 suspected crystals identified by CPLM, 569 met our inclusion criteria, and 293 (51%) were confirmed as CPP crystals. Of 175 unique confirmed crystals, 118 (67%) were rods (median area 3.6 μm

conclusionsCPP crystals that are smaller and weakly birefringent are more difficult to identify. There is likely a population of smaller, less birefringent CPP crystals that routinely goes undetected by CPLM. Describing the characteristics of poorly visible crystals may be of use for future development of novel crystal identification methods.

Indexed as

Calcium pyrophosphateCPPDCrystal arthropathyLight microscopy

Identifiers

PMID34386778
PMCPMC8356773
OpenAlexW3118641382

What OpenQuestion holds

Textmetadata
LicenceCC BY-NC-ND
Read underepoch 390

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.