Risk Of Diagnostic Error Research Articles

Definitions and Measurements for Atypical Presentations at Risk for Diagnostic Errors in Internal Medicine: Protocol for a Scoping Review.

Atypical presentations have been increasingly recognized as a significant contributing factor to diagnostic errors in internal medicine. However, research to address associations between atypical presentations and diagnostic errors has not been evaluated due to the lack of widely applicable definitions and criteria for what is considered an atypical presentation. The aim of the study is to describe how atypical presentations are defined and measured in studies of diagnostic errors in internal medicine and use this new information to develop new criteria to identify atypical presentations at high risk for diagnostic errors. This study will follow an established framework for conducting scoping reviews. Inclusion criteria are developed according to the participants, concept, and context framework. This review will consider studies that fulfill all of the following criteria: include adult patients (participants); explore the association between atypical presentations and diagnostic errors using any definition, criteria, or measurement to identify atypical presentations and diagnostic errors (concept); and focus on internal medicine (context). Regarding the type of sources, this scoping review will consider quantitative, qualitative, and mixed methods study designs; systematic reviews; and opinion papers for inclusion. Case reports, case series, and conference abstracts will be excluded. The data will be extracted through MEDLINE, Web of Science, CINAHL, Embase, Cochrane Library, and Google Scholar searches. No limits will be applied to language, and papers indexed from database inception to December 31, 2023, will be included. Two independent reviewers (YH and RK) will conduct study selection and data extraction. The data extracted will include specific details about the patient characteristics (eg, age, sex, and disease), the definitions and measuring methods for atypical presentations and diagnostic errors, clinical settings (eg, department and outpatient or inpatient), type of evidence source, and the association between atypical presentations and diagnostic errors relevant to the review question. The extracted data will be presented in tabular format with descriptive statistics, allowing us to identify the key components or types of atypical presentations and develop new criteria to identify atypical presentations for future studies of diagnostic errors. Developing the new criteria will follow guidance for a basic qualitative content analysis with an inductive approach. As of January 2024, a literature search through multiple databases is ongoing. We will complete this study by December 2024. This scoping review aims to provide rigorous evidence to develop new criteria to identify atypical presentations at high risk for diagnostic errors in internal medicine. Such criteria could facilitate the development of a comprehensive conceptual model to understand the associations between atypical presentations and diagnostic errors in internal medicine. Open Science Framework; www.osf.io/27d5m. DERR1-10.2196/56933.

Errors in clinical diagnosis: a narrative review.

Diagnostic errors are often caused by cognitive biases and sometimes by other cognitive errors, which are driven by factors specific to clinicians, patients, diseases, and health care systems. An experienced clinician diagnoses routine cases intuitively, effortlessly, and automatically through non-analytic reasoning and uses deliberate, cognitively effortful analytic reasoning to diagnose atypical or complicated clinical cases. However, diagnostic errors can never be completely avoided. To minimize the frequency of diagnostic errors, it is advisable to rely on multiple sources of information including the clinician's personal experience, expert opinion, principals of statistics, evidence-based data, and well-designed algorithms and guidelines, if available. It is also important to frequently engage in thoughtful, reflective, and metacognitive practices that can serve to strengthen the clinician's diagnostic skills, with a consequent reduction in the risk of diagnostic error. The purpose of this narrative review was to highlight certain factors that influence the genesis of diagnostic errors. Understanding the dynamic, adaptive, and complex interactions among these factors may assist clinicians, managers of health care systems, and public health policy makers in formulating strategies and guidelines aimed at reducing the incidence and prevalence of the phenomenon of clinical diagnostic error, which poses a public health hazard.

Why don’t we inform patients about the risk of diagnostic errors?

The principles of autonomy and informed consent dictate that patients who undergo a radiological examination should actually be informed about the risk of diagnostic errors. Implementing such a policy could potentially increase the quality of care. However, due to the vast number of radiological examinations that are performed in each hospital each day, financial constraints, and the risk of losing trust, patients, and income if the requirement for informed consent is not imposed by law on a state or national level, it may be challenging to inform patients about the risk of diagnostic errors. Future research is necessary to determine if and how an informed consent procedure for diagnostic errors can be implemented in clinical practice.

Erroneous Patient Tissue Contaminants in 1574 Surgical Pathology Slides: Impact on Diagnostic Error and a Novel Framework for Floater Management.

Tissue contaminants on histology slides represent a serious risk of diagnostic error. Despite their pervasive presence, published peer-reviewed criteria defining contaminants are lacking. The absence of a standardized diagnostic workup algorithm for contaminants contributes to variation in management, including investigation and reporting by pathologists. To study the frequency and type of tissue contaminants on microscopic slides using standardized criteria. Using these data, we propose a taxonomy and algorithm for pathologists on "floater" management, including identification, workup, and reporting, with an eye on patient safety. A retrospective study arm of 1574 histologic glass slides as well as a prospective study arm of 50 slide contamination events was performed. Using these data we propose a structured classification taxonomy and guidelines for the workup and resolution of tissue contamination events. In the retrospective arm of the study, we identified reasonably sized benign tissue contaminants on 52 of 1574 slides (3.3%). We found size to be an important parameter for evaluation, among other visual features including location on the slide, folding, ink, and tissue of origin. The prospective arm of the study suggested that overall, pathologists tend to use similar features when determining management of potentially actionable contaminants. We also report successfully used case-based ancillary testing strategies, including fluorescence in situ hybridization analysis of chromosomes and DNA fingerprinting. Tissue contamination events are underreported and represent a patient safety risk. Use of a reproducible classification taxonomy and a standardized algorithm for contaminant workup, management, and reporting may aid pathologists in understanding and reducing risk.

Learning from diagnostic errors to improve patient safety when GPs work in or alongside emergency departments: incorporating realist methodology into patient safety incident report analysis

BackgroundIncreasing demand on emergency healthcare systems has prompted introduction of new healthcare service models including the provision of GP services in or alongside emergency departments. In England this led to a policy proposal and £100million (US$130million) of funding for all emergency departments to have co-located GP services. However, there is a lack of evidence for whether such service models are effective and safe. We examined diagnostic errors reported in patient safety incident reports to develop theories to explain how and why they occurred to inform potential priority areas for improvement and inform qualitative data collection at case study sites to further refine the theories.MethodsWe used a mixed-methods design using exploratory descriptive analysis to identify the most frequent and harmful sources of diagnostic error and thematic analysis, incorporating realist methodology to refine theories from an earlier rapid realist review, to describe how and why the events occurred and could be mitigated, to inform improvement recommendations. We used two UK data sources: Coroners’ reports to prevent future deaths (30.7.13–14.08.18) and National Reporting and Learning System (NRLS) patient safety incident reports (03.01.05–30.11.15).ResultsNine Coroners’ reports (from 1347 community and hospital reports, 2013–2018) and 217 NRLS reports (from 13 million, 2005–2015) were identified describing diagnostic error related to GP services in or alongside emergency departments. Initial theories to describe potential priority areas for improvement included: difficulty identifying appropriate patients for the GP service; under-investigation and misinterpretation of diagnostic tests; and inadequate communication and referral pathways between the emergency and GP services. High-risk presentations included: musculoskeletal injury, chest pain, headache, calf pain and sick children.ConclusionInitial theories include the following topics as potential priority areas for improvement interventions and evaluation to minimise the risk of diagnostic errors when GPs work in or alongside emergency departments: a standardised initial assessment with streaming guidance based on local service provision; clinical decision support for high-risk conditions; and standardised computer systems, communication and referral pathways between emergency and GP services. These theories require refinement and testing with qualitative data collection from case study (hospital) sites.

Cross-contamination in molecular laboratories: A challenge to COVID-19 testing in Bangladesh

Rapid and accurate laboratory diagnosis of SARS-CoV-2 infection is crucial for the management of COVID-19 patients and control of the spread of the virus. At the start of the COVID-19 pandemic, Bangladesh had only one government molecular laboratory where real-time RT-PCR will be performed to diagnose SARS-CoV-2 infection. With the increasing number of suspected cases requiring confirmation diagnostic testing, there was a requirement to quickly expand capacity for large-scale testing. The government of Bangladesh established over 100 molecular laboratories within one year to test COVID-19. To fulfil the requirement for expanded testing, the government was compelled to recruit laboratory employees with inadequate experience, technical knowledge, and skills in molecular assays, particularly in processing specimens, interpreting results, recognizing errors, and troubleshooting. As a result, the risk of diagnostic errors, such as cross-contamination, is increased, as is that the risk of false-positive results, which might risk the patient’s health and undermine the efficacy of public health policies, public health response, surveillance programs, and restrictive measures aimed toward containing the outbreak. This review article aims to explain different sources of crosscontamination in the COVID-19 RT-PCR laboratories and the way to forestall them in efficient and practical ways.

ДИАГНОСТИКА БОЛЕЗНИ ГИРШПРУНГА У ДЕТЕЙ: МУЛЬТИЦЕНТРОВОЕ ИССЛЕДОВАНИЕ

Hirschsprung disease (HD) is a congenital absence of nerve cells (ganglions) in a segment of the intestinal wall, leading to its obstruction. Diagnosis of BG in children is a labor-intensive process, on which surgical treatment tactics depend. The concentration of patients in large surgical centers with equipped diagnostic departments makes it possible to develop the most adequate examination plan while minimizing the risk of diagnostic errors. The aim of the study was to analyze methods for diagnosis of HD in children; a retrospective analysis of the records of patients hospitalized in three medical organizations in Moscow (n=201) in 2017–2019 was carried out. The first group – children with confirmed diagnosis (n=152), the second group – patients with suspicion of BG with unsatisfactory results of previous operative treatment, postoperative complications (n=49). Results: in the 1st group, irrigography was performed before hospitalization in 118 patients (77,6%). In the hospitals, irrigography was performed (repeated) for 109 (71,7%) children. 25 (16,4%) patients showed discrepancies in interpretation of the results. Thus, irrigography was applied to all patients. Intestine biopsy before hospitalization was performed in 79 patients (52%), in the hospitals – performed/repeated in 50 patients (32,9%). There were discrepancies in the interpretation of histological findings in 8 patients (18,6 per cent). Thus, in the diagnosis of HD in children, biopsies were used (before hospitalization and/or during hospitalization) in 89 patients (58,6%). Anorectal manometry was performed to 3 (2%) children. In the 2nd group a histological examination was performed (before and during hospitalization) in 41 patients (84%), anorectal manometry – in 15 patients (31%), irrigography – in all children. Correlation analysis did not reveal any relationship between the HD variant and manifestation symptoms (Spearman's correlation coefficient was –0,232 at p<0,05. Conclusion: all medical teams began examining children with suspected HD with irrigography. Various intestinal biopsies were performed in 58,6% of cases. Anorectal manometry is currently practically not used in the diagnosis of HD in children, although it is a promising non-invasive method with high sensitivity and specificity.

Renewed Focus on the Threat of Cross-Contamination in Molecular Laboratories: Notes from the COVID-19 Testing Experience in Bangladesh

Rapid and accurate laboratory diagnosis of SARS-CoV-2 infection is crucial for the management of COVID-19 patients and control of the spread of the virus. At the start of the COVID-19 pandemic, Bangladesh had only one government molecular laboratory where real-time RT-PCR would be performed to diagnose SARS-CoV-2 infection. With the increasing number of suspected cases requiring confirmation diagnostic testing, there is a requirement to expand capacity for large-scale testing quickly. The government of Bangladesh established over 100 molecular laboratories within one year to test COVID-19. To expand the testing capacity, the government was compelled to recruit laboratory staff with limited experience and technical expertise, especially in molecular assays, to process specimens, interpret results, troubleshoot. As a result, the risk of diagnostic errors, such as cross-contamination, increased, potentially undermining the efficacy of public health policies, public health response, surveillance programs, and restrictive measures aimed toward containing the outbreak. In this piece, we discuss the different sources of cross-contamination in the COVID-19 RT-PCR laboratories and proffer practical preventive measures to avoid them.

Nowadays treatment of testicular appendix torsion in children

Introduction. Currently, a modern tactics as to the treatment of testicular appendix torsion in children is not an indisputable axiom but it is a subject of discussion in domestic and foreign literature. Modern diagnostic tools, wide implementation of expert-class equipment as well as gaining more experience have reduced, to a minimum , the risk of diagnostic error with fatal consequences for the gonad. So, it impels to revise the existing algorithms and to consider the conservative treatment as the method of choice in uncomplicated testicular appendix torsion.Objective. To analyze the gained experience in treating testicular appendix torsion and to suggest reasonable algorithms which correspond to modern diagnostic techniques and treatment options. Material and methods. 2875 cases with testicular appendix torsion have been analyzed. Of these, 2 069 (71.96%) patients were operated on; 755 (26.26%) patients had conservative treatment and 51 (1.78%) had to be operated on despite conservative treatment.Results. The material obtained in three statistically homogeneous groups has been аnalyzed. When comparing clinical and ultrasound criteria, it was found out that the incidence of orchalgia in the surgical group is slightly higher than in the conservative one. It may indicate that the adhesive process in the scrotal cavity after surgical trauma is more frequent than after a possible aseptic inflammation. Asymmetry of gonad volumes with smaller diseased testicle was seen in all groups. The decrease in testicular volume is minimal in all cases and is not statistically significant. The incidence of heterogeneity in the testicular and appendage echo structure, which indicates sclerotic changes in the parenchyma, is also not statistically significant in the analyzed groups. Patients who were operated despite their conservative care do not have much worse outcomes after long-lasting follow-up period than groups with other curative options.Conclusion. Torsion of the testicular appendix in children is a challenging problem that is far from being solved. There is no consensus as to the indications for surgical treatment and to the assessment of postoperative outcomes. Modern diagnostic and monitoring techniques allow to dynamically monitor the scrotal organs in conservative treatment. The conservative treatment of testicular appendix torsion is an effective and safe method. The conservative tactics which was changed for surgical one does not lead to gonad deterioration.

SAFER PRACTICES in the COVID-19 pandemic

COVID-19 has created a wave of uncertainty for nurses and healthcare practitioners, with new information on the virus being released constantly. Paul Silverston discusses the assessment of patients with symptoms of COVID-19 and how to reduce the risk of misdiagnosis Errors in diagnosis are relatively common in primary care which often result in serious harm to patients. The majority of these errors are preventable. This article describes a diagnostic error checklist, SAFER PRACTICES, which can be used to help clinicians prepare themselves for consulting in patients with suspected or confirmed COVID-19 disease so that they come to the consultation with the correct medical knowledge, clinical assessment plan and diagnostic reasoning required to reduce the risk of diagnostic error. It can also be used during the consultation to deliver a systematic approach to the prevention and detection of diagnostic errors.

SAFER PRACTICES: reducing the risk of diagnostic errors

Diagnostic errors are relatively common in general practice. Paul Silverston describes a mnemonic-based system to prevent and detect these errors Diagnostic errors in primary care are relatively common and they have the potential to cause serious harm to patients. Up to 80% of these errors are believed to be preventable. This article describes a mnemonic-based system that practice nurses can use to prevent diagnostic errors from arising, as well as to detect these errors when they occur. The mnemonic is designed to be used pre-consultation to reduce the risk of errors arising through better preparation; during the consultation, as a diagnostic error checklist; and after the consultation to encourage reflective practice and critical thinking.

Frequency, Risk Factors, Causes, and Consequences of Diagnostic Errors in Critically Ill Medical Patients: A Retrospective Cohort Study.

Diagnostic errors are a source of significant morbidity and mortality but understudied in the critically ill. We sought to characterize the frequency, causes, consequences, and risk factors of diagnostic errors among unplanned ICU admissions. We conducted a retrospective cohort study of randomly selected nonsurgical ICU admissions between July 2015 and June 2016. Medical ICU at a tertiary academic medical center. Critically ill adults with unplanned admission to the medical ICU. The primary investigator reviewed patient records using a modified version of the Safer Dx instrument, a validated instrument for detecting diagnostic error. Two intensivists performed secondary reviews of possible errors, and reviewers met periodically to adjudicate errors by consensus. For each confirmed error, we judged harm on a 1-6 rating scale. We also collected detailed demographic and clinical data for each patient. We analyzed 256 unplanned ICU admissions and identified 18 diagnostic errors (7% of admissions). All errors were associated with harm, and only six errors (33%) were recognized by the ICU team within the first 24 hours. More women than men experienced a diagnostic error (11.7% vs 2.7%; p = 0.015, χ test). On multivariable logistic regression analysis, female sex remained independently associated with risk of diagnostic error both at admission (odds ratio, 5.18; 95% CI, 1.34-20.08) and at 24 hours (odds ratio, 11.6; 95% CI, 1.37-98.6). Similarly, Quick Sequential Organ Failure Assessment score greater than or equal to 2 at admission was independently associated with diagnostic error (odds ratio, 5.73; 95% CI, 1.72-19.01). Diagnostic errors may be an underappreciated source of ICU-related harm. Women and higher acuity patients appear to be at increased risk for such errors. Further research is merited to define the scope of error-associated harm and to clarify risk factors for diagnostic errors among the critically ill.

Right diagnosis, right treatment: SAFER PRACTICES

Choosing the right treatment for the patient requires that the right diagnosis is made first. In primary and ambulatory care, however, diagnostic errors are both common and commonly preventable. The World Health Organization has recommended that all health professionals should receive formal training in the principles of diagnostic reasoning and the causes of diagnostic error, and that strategies and interventions to reduce the risk of diagnostic error should be used in clinical practice. This article describes a mnemonic checklist, SAFER PRACTICES, which can be used in an integrated approach to the prevention and detection of diagnostic errors that starts in the classroom and continues through to the consulting room.

Criteria for Differentiation of Non-Bacterial and Haematogenous Osteomyelitis: A Case-Control Study With Prospective Verification of the Outcomes

Background. Patients with haematogenous and non-bacterial osteomyelitis have similar clinical symptoms (pain in the nidus area, soft tissue swelling, fever) and laboratory signs (increased erythrocyte sedimentation rate, leukocyte count, C-reactive protein concentration). The criteria for distinguishing these two states are not determined.Objective. Our aim was to determine diagnostic criteria to differentiate haematogenous and non-bacterial osteomyelitis.Methods. The study included data of patients under the age of 18 years with non-bacterial or haematogenous osteomyelitis hospitalised to two clinical centres from 2009 to 2016. The diagnosis was established and re-verified according to archival data (medical history) and after two years of observation (at least once a year). Clinical, anamnestic and laboratory data (haemoglobin, leukocytes, leukocyte formula, platelets, ESR and C-reactive protein, CRP) as well as the results of radiation diagnostics (X-ray, CT scan, MRI or osteosyntigraphy) obtained at the disease onset were taken into account as potential diagnostic criteria.Results. Out of 145 patients with non-bacterial or haematogenous osteomyelitis, the diagnosis was re-verified in 138, of them non-bacterial osteomyelitis — in 91, haematogenous osteomyelitis — in 47. The following criteria had the highest diagnostic value for establishing cases of non-bacterial osteomyelitis: detection of bone destruction foci surrounded by osteosclerosis area [sensitivity (Se) 1.0; specificity (Sp) 0.79]; absence of fever (Se 0.66; Sp 0.92); the number of bone destruction foci > 1 (Se 0.73; Sp 1.0); CRP 55 mg/L (Se 0.94; Sp 0.73); negative results of bacteriological examination of the material from the bone destruction focus (Se 1.0; Sp 0.67).Conclusion. Diagnostic criteria for differentiation of non-bacterial and haematogenous osteomyelitis have been described. Further research on the efficacy of using these criteria to reduce the risk of diagnostic errors, decrease the diagnostic pause, reduce the risk of non-bacterial osteomyelitis complications is needed.

Risk of diagnostic errors when dealing with aggressive patients: Experimental study.

Medical errors are still common despite advances in technology and policies to insure patients' safety. They can be traceable as in medications or surgical errors, but may not be so in diagnostic errors that are patient, physician, or system related. This study aimed to explore whether aggressive behavior of some patients might affect physicians' clinical reasoning and decision-making. The study was conducted in a format of observation skills clinical examinations (OSCEs). It included simulating patients (SPs) and family physicians in residency training in a clinical setup. The experiment included two arms of dealing with case scenarios with "Neutral" and "Aggressive" behaviors. Explanatory variables assessed were duration of consultation, correct diagnosis, and plan of appropriate management as well as patients' satisfaction. Participants were 14 trained SPs who played the roles of aggressive and nonaggressive patients when they encountered 35 residents (18 were males) in family physicians [year 2 (R2), year 3 (R3) and year 4 (R4)]; in a total of seventy patient/doctor encounters. Compared with nonaggressive patients, aggressive patients had statistically significantly prolonged OSCE duration [mean (standard deviation) = 6.89 (1.35) and 6.11 (157) min, respectively; P = 0.031] and more patient consultation satisfaction (P <0.0001). However, no statistically significant differences were found in diagnostic accuracy (P = 0.626) and management (P = 0.621). In a stratified analysis, junior doctors had longer duration of consultation and seemed to perform better in management (higher patient satisfaction and better management outline) than their senior counterparts. Patients' aggressive behavior led to longer duration of medical consultation. Poor management plan, albeit correct diagnosis, in senior doctors may be due to disruptive clinical reasoning in disturbed stressful situation. Coping strategies should be emphasized in medical education to ensure effective clinical reasoning in patient/doctor encounters.

PERITONITE OR DEBUT OF DIABETES MELLITUS

Peritonitis is a common complication in pediatric surgery. It can occur not only in acute surgical pathology, but also in diseases of the general pediatric profile, for example, in diabetes mellitus. Quite often just the peritonitis is the manifestation of diabetes mellitus. However, when there is a syndrome of the “acute” abdomen, “stressful” hyperglycemia may occur, which is aimed at maintaining the vital activity of the body. Determination the level of blood glucose fails to provide an opportunity to differentiate them. There is always a risk of diagnostic errors.

Diagnostic Error in Correctional Mental Health: Prevalence, Causes, and Consequences.

While they have important implications for inmates and resourcing of correctional institutions, diagnostic errors are rarely discussed in correctional mental health research. This review seeks to estimate the prevalence of diagnostic errors in prisons and jails and explores potential causes and consequences. Diagnostic errors are defined as discrepancies in an inmate's diagnostic status depending on who is responsible for conducting the assessment and/or the methods used. It is estimated that at least 10% to 15% of all inmates may be incorrectly classified in terms of the presence or absence of a mental illness. Inmate characteristics, relationships with staff, and cognitive errors stemming from the use of heuristics when faced with time constraints are discussed as possible sources of error. A policy example of screening for mental illness at intake to prison is used to illustrate when the risk of diagnostic error might be increased and to explore strategies to mitigate this risk.

Non-heart-beating donors are ineligible

The death of the donor is a mandatory prerequisite for organ transplantation (dead donor rule) worldwide. It is a medical, legal and ethical consensus to accept the concept of brain death, as first proposed in 1968 by the ad hoc committee of the Harvard Medical School, as a certain criterion of death. In isolated cases where the diagnosis of brain death was claimed to be wrong, it could be demonstrated that the diagnostic procedure for brain death had not been correctly performed. In March 2014 a joint statement by the German neuromedical societies emphasized that 1) the diagnosis of brain death is one of the safest diagnoses in medicine if performed according to accepted medical standards and criteria and 2) the concept of non-heart-beating donors (NHBD, i. e. organ donation after an arbitrarily defined duration of circulatory and cardiac arrest) practiced in some European countries must be absolutely rejected because it implicates a high risk of diagnostic error. According to the current literature it is unclear at what time cardiac and circulatory arrest is irreversible and leads to irreversible cessation of all functions of the entire brain including the brainstem, even though clinical signs of cessation of brain functions are always found after 10min. Furthermore, is it often an arbitrary decision to exactly define the duration of cardiac arrest if continuous echocardiographic monitoring has not been carried out from the very beginning. Last but not least there are ethical concerns against the concept of NHBD because it might influence therapeutic efforts to resuscitate a patient with cardiac arrest. Therefore, the German Medical Council (BÄK) has repeatedly rejected the concept of NHBD for organ transplantation since 1995.

Karyomapping identifies second polar body DNA persisting to the blastocyst stage: implications for embryo biopsy

Blastocyst biopsy is now widely used for both preimplantation genetic screening (PGS) and preimplantation genetic diagnosis (PGD). Although this approach yields good results, variable embryo quality and rates of development remain a challenge. Here, a case is reported in which a blastocyst was biopsied for PGS by array comparative genomic hybridization on day 6 after insemination, having hatched completely. In addition to a small trophectoderm sample, excluded cell fragments from the subzonal space from this embryo were also sampled. Unexpectedly, the array comparative genomic hybridization results from the fragments and trophectoderm sample were non-concordant: 47,XX,+19 and 46,XY, respectively. DNA fingerprinting by short tandem repeat and amelogenin analysis confirmed the sex chromosome difference but seemed to show that the two samples were related but non-identical. Genome-wide single nucleotide polymorphism genotyping and karyomapping identified that the origin of the DNA amplified from the fragments was that of the second polar body corresponding to the oocyte from which the biopsied embryo developed. The fact that polar body DNA can persist to the blastocyst stage provides evidence that excluded cell fragments should not be used for diagnostic purposes and should be avoided when performing embryo biopsies as there is a risk of diagnostic errors.

Bone densitometry in clinical practice

In this paper an information on the features of bone densitometry on DEXA devices was presented, and basic errors that can occur during the execution of the study or assessment of patients data after their examination were specified. Bone densitometry is an important informative method of examination allowing to detect not only qualitative and quantitative indicators of bone condition but to perform also monitoring which is important after medicament therapy for evaluation of effectiveness of treatment of osteoporosis. The method makes it possible to detect deformations and fractures of the vertebral bodies as well as to assess quantitatively change of their shape. For measurement of bone mineral density on the lumbar spine they use AP-projection LI–LIV. If in the area of the research there are vertebrae with destructive disorders they exclude them from the analysis and carry out diagnostics according two vertebral bodies without any violations. The difference between the vertebral bodies should not be 1 SD in accordance with T-criterion. Orthopedic programs incorporated into the device make it possible to describe bone tissue condition in the area of contact with the implant after arthroplasty. Quantitative evaluation of bone mass adjacent to the implant implanted into the hip joint they performed in Gruen zones which they determine in frontal plane with the prone position of a patient after 2–3 weeks after arthroplasty and consider as basic assessment. One may assess the condition of the entire skeleton, fat and fat-free body mass which is important for examination of children and patients with endocrine disorders, identifying sarkopenia, in the case of obesity, malabsorption syndrome and so on. Interpreting the results one should also take into account some features of this method of patient examination for reducing the risk of diagnostic errors.