The needle in the haystack: Histology of post-mortem computed tomography guided biopsies versus autopsy derived tissue

Infectious diseases and the role of needle biopsy post-mortem

Post-mortem examinations continue to play a crucial role in understanding the epidemiology and pathogenesis of infectious diseases. However, the perceived infection risk can preclude traditional, invasive, complete diagnostic autopsy. Post-mortem examination is especially important in emerging infectious diseases with potentially unknown infection risks, but rapid acquisition of good quality tissue samples is needed as part of the scientific and public health response. Needle biopsy post-mortem is a minimally invasive, rapid, closed-body autopsy technique that was originally developed to minimise the infection risk to practitioners. Since its inception, needle biopsy post-mortem has also been used as a technique to support complete diagnostic autopsy provision in poorly resourced regions and to facilitate post-mortem examinations in communities that might have religious or cultural objections to an invasive autopsy. This Review analyses the evolution and applicability of needle biopsy post-mortem in investigating endemic and emerging infectious diseases.

Efficacy of postmortem CT and tissue sampling in establishing the cause of death in clinical practice: a prospective observational study

AIMS

The aim of this study is to evaluate whether agreement with autopsy-determined cause of death (COD) increases by use of postmortem CT (PMCT) or PMCT in combination with postmortem sampling (PMS), when compared with clinical assessment only.

METHODS

This prospective observational study included deceased patients from the intensive care unit and internal medicine wards between October 2013 and August 2017. The primary outcome was percentage agreement on COD between the reference standard (autopsy) and the alternative postmortem examinations (clinical assessment vs PMCT or PMCT+PMS). In addition, the COD of patient groups with and without conventional autopsy were compared with respect to involved organ systems and pathologies.

RESULTS

Of 730 eligible cases, 144 could be included for analysis: 63 underwent PCMT without autopsy and 81 underwent both PMCT and autopsy. Agreement with autopsy-determined COD was significantly higher for both PMCT with PMS (42/57, 74%), and PMCT alone (53/81, 65%) than for clinical assessment (40/81, 51%; p=0.007 and p=0.03, respectively). The difference in agreement between PMCT with PMS and PMCT alone was not significant (p=0.13). The group with autopsy had a significantly higher prevalence of circulatory system involvement and perfusion disorders, and a lower prevalence of pulmonary system involvement.

CONCLUSION

PMCT and PMS confer additional diagnostic value in establishing the COD. Shortcomings in detecting vascular occlusions and perfusion disorders and susceptibility to pulmonary postmortem changes could in future be improved by additional techniques. Both PMCT and PMS are feasible in clinical practice and an alternative when autopsy cannot be performed.

Diagnostic value of T1- and T2-weighted 3-Tesla MRI for postmortem detection and age stage classification of myocardial infarction

The aims of this study are to retrospectively evaluate the diagnostic value of T1- and T2-weighted 3-T magnetic resonance imaging (MRI) for postmortem detection of myocardial infarction (MI) in terms of sensitivity and specificity and to compare the MRI appearance of the infarct area with age stages. Postmortem MRI examinations (n = 88) were retrospectively reviewed for the presence or absence of MI by two raters blinded to the autopsy results. The sensitivity and specificity were calculated using the autopsy results as the gold standard. A third rater, who was not blinded to the autopsy findings, reviewed all cases in which MI was detected at autopsy for MRI appearance (hypointensity, isointensity, hyperintensity) of the infarct area and the surrounding zone. Age stages (peracute, acute, subacute, chronic) were assigned based on the literature and compared with the age stages reported in the autopsy reports. The interrater reliability between the two raters was substantial (κ = 0.78). Sensitivity was 52.94% (both raters). Specificity was 85.19% and 92.59%. In 34 decedents, autopsy identified an MI (peracute: n = 7, acute: n = 25, chronic: n = 2). Of 25 MI classified as acute at autopsy, MRI classified peracute in four cases and subacute in nine cases. In two cases, MRI suggested peracute MI, which was not detected at autopsy. MRI could help to classify the age stage and may indicate the area for sampling for further microscopic examination. However, the low sensitivity requires further additional MRI techniques to increase the diagnostic value.

Cause of death and the autopsy rate in an elderly population

Autopsy rates are declining, while major discrepancies between autopsies and clinical diagnoses remain. Still, little is known about the impact of suspected underlying diseases, for example, a diagnosis of cancer, on the autopsy rate. The aim of this study was to investigate the relation between the clinical cause of death, a history of cancer, and the medical autopsy rate using data from the Netherlands Cohort Study on Diet and Cancer (NLCS), a large prospective cohort study with a long follow-up. The NLCS is a prospective study initiated in 1986 and includes 120,852 persons (58,279 males and 62,573 females), 55-69 years of age at the time of enrollment. The NLCS was linked with the Dutch Nationwide Pathology Databank (PALGA), the Dutch Population Register (GBA), the Netherlands Cancer Registry, and the causes of death registry (Statistics Netherlands). If applicable, the 95% confidence intervals were calculated. During the follow-up of the NLCS, 59,760 deaths were recorded by linkage with the GBA from 1991 until 2009. Of these, a medical autopsy was performed on 3736 deceased according to linkage with PALGA, resulting in an overall autopsy rate of 6.3%. Major variations in the autopsy rate were observed according to the cause of death. The autopsy rate increased according to the number of contributing causes of death. Lastly, a diagnosis of cancer affected the autopsy rate. The clinical cause of death and a history of cancer both influenced the medical autopsy rate in a large national cohort. The insight this study provides may help clinicians and pathologists counteracting the further downfall of the medical autopsy.

Needle placement accuracy in CT-guided robotic post mortem biopsy

Forensic autopsies include a thorough examination of the corpse to detect the source or alleged manner of death as well as to estimate the time since death. However, a full autopsy may be not feasible due to limited time, cost or ethical objections by relatives. Hence, we propose an automated minimal invasive needle biopsy system with a robotic arm, which does not require any online calibrations during a procedure. The proposed system can be easily integrated into the workflow of a forensic biopsy since the robot can be flexibly positioned relative to the corpse. With our proposed system, we performed needle insertions into wax phantoms and livers of two corpses and achieved an accuracy of 4.34 ± 1.27 mm and 10.81 ± 4.44 mm respectively.

Introduction of postmortem CT increases the postmortem examination rate without negatively impacting the rate of traditional autopsy in daily practice: an implementation study

AIM

The aim of this implementation study was to assess the effect of postmortem CT (PMCT) and postmortem sampling (PMS) on (traditional) autopsy and postmortem examination rates. Additionally, the feasibility of PMCT and PMS in daily practice was assessed.

METHODS

For a period of 23 months, PMCT and PMS were used as additional modalities to the autopsy at the Department of Internal Medicine. The next of kin provided consent for 123 postmortem examinations. Autopsy rates were derived from the Dutch Pathology Registry, and postmortem examination rates were calculated for the period before, during and after the study period, and the exclusion rate, table time, time interval to informing the referring clinicians with results and the time interval to the Multidisciplinary Mortality Review Board (MMRB) meeting were objectified to assess the feasibility.

RESULTS

The postmortem examination rate increased (from 18.8% to 32.5%, p<0.001) without a decline in the autopsy rate. The autopsy rate did not change substantially after implementation (0.2% decrease). The exclusion rate was 2%, the table time was 23 min, and a median time interval of 4.1 hours between PMCT and discussing its results with the referring clinicians was observed. Additionally, more than 80% of the MMRB meetings were held within 8 weeks after the death of the patient.

CONCLUSIONS

Our study shows that the implementation of a multidisciplinary postmortem examination is feasible in daily practice and does not adversely affect the autopsy rate, while increasing the postmortem examination rate.

Added value of post-mortem computed tomography (PMCT) to clinical findings for cause of death determination in adult "natural deaths"

Purpose

The aim of this study was to investigate whether post-mortem computed tomography (PMCT) provides additional information regarding the cause of death and underlying diseases in a general practitioners’ (GP), out-of-hospital population.

Methods and materials

Bodies donated to our anatomy department between January 2014 and January 2018, who consecutively underwent a total body PMCT and had given permission for retrieval of their medical records during life, were included. PMCT scans were assessed by a radiologist and compared with the cause of death as stated in the medical records. Discrepancies were analyzed with an adjusted Goldman classification.

Results

Ninety-three out of the 274 scanned donors during the inclusion period had given consent for the retrieval of their medical records, of which 79 GP’s responded to the request thereof (31 men, 48 women, average age 72.8 years, range 36–99). PMCT identified 49 (62%) cases of cancer, 10 (12.7%) cardiovascular diseases, 8 (10.1%) severe organ failures, 5 (6.3%) cases with signs of pneumonia, 2 (2.5%) other causes, and 7 (8.9%) cases without an (underlying) definitive cause of death. Eleven major discrepancies on the Goldman classification scale, with possible relevance to survival between PMCT and GP records, were identified.

Conclusion

PMCT can have added value for the detection of additional findings regarding the cause of death in an out-of-hospital, GP’s population, especially to identify or exclude major (previously non-diagnosed) underlying diseases.

Does the medical autopsy still have a place in the current diagnostic process? A 6-year retrospective study in two French University hospitals

Medical autopsies have been in considerable decline for several decades, in France and worldwide. We aimed to determine whether a medical autopsy still currently has a role to play in diagnosis, by analyzing its performance and diagnostic limitations. This dual-centre retrospective descriptive study included all medical autopsies performed in the university hospitals of Lille and Marseille, France, between January 2007 and December 2012. Autopsies of fetuses or stillborn infants, or those related to sudden infant deaths and research protocols were excluded. 412 medical autopsies were included. The male:female ratio was 1.5:1 and mean age was 27.3 years. Half of all autopsies were pediatric. Regarding anatomical region and/or injury mechanism, a clinical diagnosis was suggested in 52.2% of cases, an autopsy diagnosis in 55.6% and a microscopic diagnosis in 81.8%. There was very low agreement between the clinician's suggested diagnosis and the final diagnosis, both for organ specific diseases and cause of death. Agreement was moderate between autopsy diagnoses and microscopic diagnoses for organ specific diseases and low for cause of death. From our findings we concluded that an autopsy associated with microscopic examination was still valuable in diagnosing cause of death. Microscopic examination was indispensable to determine certain causes of death.