International consensus guideline for reporting transmission electron microscopy results in the diagnosis of Primary Ciliary Dyskinesia

Author(s):  
Amelia Shoemark ◽  
Mieke Boon ◽  
Christoph Brochhausen ◽  
Zuzanna Bukowy-Bieryllo ◽  
Maria Margherita De Santi ◽  
...  
Diagnostics ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 524
Author(s):  
Andreia L. Pinto ◽  
Ranjit K. Rai ◽  
Claire Hogg ◽  
Thomas Burgoyne

Primary ciliary dyskinesia (PCD) is a disorder that affects motile cilia in the airway that are required for the removal of mucus, debris, and pathogens. It is important to diagnose PCD in early childhood to preserve lung function. The confirmation of a diagnosis relies on the assessment of ciliary ultrastructure by transmission electron microscopy (TEM). TEM involves the quantitative assessment of the ciliary ultrastructure to identify PCD defects as well as abnormalities resulting from infection. Many specialist diagnostic centres still rely on physical counters to tally results and paper notes to summarise findings before transferring the results to computer databases/records. To speed up the diagnostic data collection and increase the protection of patient information, we have developed digital ciliary feature counters that conform to the PCD reporting international consensus guideline. These counters can be used on a computer or tablet, and automatically generate notes regarding sample observations. We show that the digital counters are easy to use and can generate TEM diagnostic reports that will be useful for many PCD diagnostic centres.


2020 ◽  
Vol 55 (4) ◽  
pp. 1900725 ◽  
Author(s):  
Amelia Shoemark ◽  
Mieke Boon ◽  
Christoph Brochhausen ◽  
Zuzanna Bukowy-Bieryllo ◽  
Maria M. De Santi ◽  
...  

Primary ciliary dyskinesia (PCD) is a heterogeneous genetic condition. European and North American diagnostic guidelines recommend transmission electron microscopy (TEM) as one of a combination of tests to confirm a diagnosis. However, there is no definition of what constitutes a defect or consensus on reporting terminology. The aim of this project was to provide an internationally agreed ultrastructural classification for PCD diagnosis by TEM.A consensus guideline was developed by PCD electron microscopy experts representing 18 centres in 14 countries. An initial meeting and discussion were followed by a Delphi consensus process. The agreed guideline was then tested, modified and retested through exchange of samples and electron micrographs between the 18 diagnostic centres.The final guideline a) provides agreed terminology and a definition of Class 1 defects which are diagnostic for PCD; b) identifies Class 2 defects which can indicate a diagnosis of PCD in combination with other supporting evidence; c) describes features which should be included in a ciliary ultrastructure report to assist multidisciplinary diagnosis of PCD; and d) defines adequacy of a diagnostic sample.This tested and externally validated statement provides a clear guideline for the diagnosis of PCD by TEM which can be used to standardise diagnosis internationally.


2021 ◽  
Author(s):  
Mitra Rezaei ◽  
Amirali Soheili ◽  
Atefeh Fakharian ◽  
Hamid Jamaati ◽  
Jahangir Ghorbani ◽  
...  

Abstract Background: Primary ciliary dyskinesia (PCD) is a rare autosomal recessive condition of often chronic respiratory infections in early life. A useful tool for early diagnosis of such ciliary abnormalities is transmission electron microscopy (TEM). This study aimed to use TEM to examine these defects and speculate on a diagnosis.Methods: From 2017 to 2019, all referral patients with suspected PCD symptoms were included in this study. Nasal samples were taken after exclusion of further potential differential diagnosis and prepared for TEM. The final diagnosis was based on the International Consensus Guideline for reporting transmission electron microscopy results in the diagnosis of PCD. A descriptive analysis of demographic and ciliary ultrastructural data was performed by SPSS ver 21.Results: Study population consisted of 37 women and 30 men (mean age=20.34±10.7 years). The clinical presentations were as follows: bronchiectasis: 26 patients (38.8%); sinusitis: 23(34.3%); recurrent respiratory infection: 21 patients (31.3%); auditory symptoms: 5 patients (7.5%); situs inversus: 3 patients (4.4%); productive cough: 2 patients (3%); infertility: 2 patients (3%); polyposis: 1 patient (1.5%). According to TEM analysis, 12 (17%) of patients were PCD, 11 (15.7%) were indicating PCD cases, 26 (37.1%) of them had no criteria of PCD and 18 (25.7%) of cases had normal ciliary ultrastructure. Compound cilia and extra-tubule were reported in 29 (41.4%) and 31(44.3%) of patients, respectively. The outer dynein arm defect was seen in 11(16.4%) cases and the inner dynein arm (IDA) defect was seen in 20 (29.8%) cases. Two patients (3%) had microtubular disorganization.Conclusion: Bronchiectasis and sinusitis were the most common complications. The compound cilia and extra-tubule were the most prevalent TEM finding among all participants. However, the most prevalent hallmark diagnostic defects among PCD patients were ODA and IDA defects among PCD patients. Other diagnostic PCD tests should also be performed in patients in the indicating PCD group, those without PCD criteria, and normal patients with a highly suggestive history. Cell-culture, as well, should confirm IDA defects. This study highlights the fundamental need to consider ciliary defect among probable diagnoses and use TEM as a practical diagnostic tool.


Diagnostics ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1063
Author(s):  
Andreia Lucia Pinto ◽  
Ranjit Kaur Rai ◽  
Amelia Shoemark ◽  
Claire Hogg ◽  
Thomas Burgoyne

Primary ciliary dyskinesia (PCD) is a disorder affecting motile cilia. An early accurate diagnosis helps prevent lung damage and preserve lung function. To make a diagnostic assessment, one of the commonly used methods that allows for the examination of ciliary ultrastructure is transmission electron microscopy (TEM). This allows for a quantitative assessment of ciliary components to identify defects associated with PCD. Heavy metal staining is required to provide a contrast when imaging cilia in the TEM. One of the most commonly used stains is uranyl acetate (UA). UA can be applied to cellular material before embedding (en bloc), or to ultrathin sections of embedded samples (grid staining). UA is radioactive and, due to growing safety concerns and restrictions by government bodies, universities and hospitals, it is essential to find a suitable alternative. We show UA-zero (UAZ), when used en bloc, provides a high contrast and is a suitable replacement for UA. PCD diagnostic experts, having reviewed ciliary cross-sections stained with UAZ en bloc, are confident that the staining and PCD defects are readily detectable similar to samples that have been stained with UA.


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