ABSTRACT
May-Grünwald-Giemsa (MGG) stain is a Romanowsky-type, polychromatic stain as those of Giemsa, Leishman and Wright. Apart being the reference method of haematology, it has become a routine stain of diagnostic cytopathology for the study of air-dried preparations (lymph node imprints, centrifuged body fluids and fine needle aspirations). In the context of their actions of promoting the principles of quality assurance in cytopathology, the French Association for Quality Assurance in Anatomic and Cytologic Pathology (AFAQAP) and the French Society of Clinical Cytology (SFCC) conducted a proficiency test on MGG stain in 2013. Results from the test, together with the review of literature data allow pre-analytical and analytical steps of MGG stain to be updated. Recommendations include rapid air-drying of cell preparations/imprints, fixation using either methanol or May-Grünwald alone for 3-10minutes, two-step staining: 50% May-Grünwald in buffer pH 6.8 v/v for 3-5minutes, followed by 10% buffered Giemsa solution for 10-30minutes, and running water for 1-3minutes. Quality evaluation must be performed on red blood cells (RBCs) and leukocytes, not on tumour cells. Under correct pH conditions, RBCs must appear pink-orange (acidophilic) or buff-coloured, neither green nor blue. Leukocyte cytoplasm must be almost transparent, with clearly delineated granules. However, staining may vary somewhat and testing is recommended for automated methods (slide stainers) which remain the standard for reproducibility. Though MGG stain remains the reference stain, Diff-Quik(®) stain can be used for the rapid evaluation of cell samples.
Subject(s)
Coloring Agents , Cytodiagnosis/standards , Eosine Yellowish-(YS) , Methylene Blue , Practice Guidelines as Topic , Staining and Labeling/methods , Automation , Azure Stains , Cell Biology/organization & administration , Coloring Agents/chemistry , Cytodiagnosis/methods , Eosine Yellowish-(YS)/chemistry , Erythrocytes/ultrastructure , France , Humans , Hydrogen-Ion Concentration , Leukocytes/ultrastructure , Methylene Blue/chemistry , Organelles/ultrastructure , Quality Assurance, Health Care , Reproducibility of Results , Societies, Scientific , Staining and Labeling/instrumentation , Staining and Labeling/standards , Tissue Fixation/methods , XanthenesABSTRACT
Human papillomaviruses (HPV), double-stranded DNA viruses, are causing many mucocutaneous diseases, benign or malignant, ranging from common warts to malignancies involving the upper aerodigestive tract and the anogenital sphere. The diagnosis of HPV infection is based primarily on the viral genome detection by molecular biological methods, given the difficulty in routine cultivation of these viruses. The current trend in screening against cervical cancer is to improve the sensitivity of screening with new methods and to propose new algorithms for diagnostic and therapeutic decisions. The development of liquid-based cytology facilitates the cytologic diagnosis and molecular assays from the same sample. There are two main types of HPV detection methods used on uterine cervical samples: signal amplification methods (hybridization techniques in liquid phase) and target amplification methods (the techniques of gene amplification or Polymerase Chain Reaction [PCR]). Genotyping techniques are also developed: they are based on an amplification technique followed by hybridization with probe specific types. In addition to the detection, genotyping techniques allow quantitative detection of viral DNA of HPV genotype and so monitor changes in viral load over time. Another approach relies on the detection of messenger RNA (mRNA) of HPV proteins E6 and E7 oncogenes, which would appear to be a relevant marker to identify and monitor women at risk of progression to a precancerous lesion or cervical cancer.
Subject(s)
Alphapapillomavirus/isolation & purification , DNA, Viral/analysis , Genotyping Techniques , Human Papillomavirus DNA Tests/methods , Mass Screening/methods , Papillomavirus Infections/virology , Precancerous Conditions/virology , Uterine Cervicitis/virology , Alphapapillomavirus/classification , Alphapapillomavirus/genetics , Betapapillomavirus/classification , Betapapillomavirus/genetics , Betapapillomavirus/isolation & purification , Female , Genome, Viral , Humans , Nucleic Acid Hybridization/methods , Oligonucleotide Array Sequence Analysis , Oncogene Proteins, Viral/genetics , Papillomavirus Infections/diagnosis , Papillomavirus Infections/pathology , Polymerase Chain Reaction/methods , Precancerous Conditions/diagnosis , Precancerous Conditions/pathology , RNA, Messenger/analysis , RNA, Viral/analysis , Reagent Kits, Diagnostic , Uterine Cervical Neoplasms/diagnosis , Uterine Cervical Neoplasms/pathology , Uterine Cervical Neoplasms/virology , Uterine Cervicitis/diagnosis , Uterine Cervicitis/pathologyABSTRACT
Modern laboratory management software must be able to produce pathological reports for all specimens referred for diagnostic analysis, and must also be able to ensure improved quality for each step of the diagnostic process. Indices of diagnostic quality useful for staff members should be made available. The management software should enable user-friendly analysis and comparison in order to choose what kind of changes should to be applied for appropriate implementation of Quality Assurance procedures. This methodology is especially useful for Papsmears.
