Amyloid-Forming Corpora Amylacea and Spheroid-Type Amyloid Deposition: Comprehensive Analysis Using Immunohistochemistry, Proteomics, and a Literature Review

This study aimed to elucidate the similarities and differences between amyloid-forming corpora amylacea (CA) in the prostate and lung, examine the nature of CAs in cystic tumors of the atrioventricular node (CTAVN), and clarify the distinctions between amyloid-forming CA and spheroid-type amyloid deposition. We conducted proteomics analyses using liquid chromatography-tandem mass spectrometry with laser microdissection and immunohistochemistry to validate the characteristics of CAs in the lung and prostate. Our findings revealed that the CAs in these organs primarily consisted of common proteins (β2-microglobulin and lysozyme) and locally produced proteins. Moreover, we observed a discrepancy between the histopathological and proteomic analysis results in CTAVN-associated CAs. In addition, while the histopathological appearance of the amyloid-forming CAs and spheroid-type amyloid deposits were nearly identical, the latter deposition lacked β2-microglobulin and lysozyme and exhibited evident destruction of the surrounding tissue. A literature review further supported these findings. These results suggest that amyloid-forming CAs in the lung and prostate are formed through a shared mechanism, serving as waste containers (wasteosomes) and/or storage for excess proteins (functional amyloids). In contrast, we hypothesize that while amyloid-forming CA and spheroid-type amyloid deposits are formed, in part, through common mechanisms, the latter are pathological.

Revisiting the relevance of Hirano bodies in neurodegenerative diseases

AIMS

Hirano bodies (HBs) are eosinophilic pathological structures with two morphological phenotypes commonly found in the hippocampal CA1 region in Alzheimer's disease (AD). This study evaluated the prevalence and distribution of HBs in AD and other neurodegenerative diseases.

METHODS

This cross-sectional study systematically evaluated HBs in a cohort of 193 cases with major neurodegenerative diseases, including AD (n = 91), Lewy body disease (LBD, n = 87), progressive supranuclear palsy (PSP, n = 36), multiple system atrophy (MSA, n = 14) and controls (n = 26). The prevalence, number and morphology of HBs in the stratum lacunosum (HBL) and CA1 pyramidal cell layer were examined. In addition, we investigated the presence of HBs in five additional hippocampal subregions.

RESULTS

The morphological types of HBs in CA1 were divided into three, including a newly discovered type, and were evaluated separately, with their morphology confirmed in three dimensions: (1) classic rod-shaped HB (CHB), (2) balloon-shaped HB (BHB) and the newly described (3) string-shaped HB (SHB). The prevalence of each HB type differed between disease groups: Compared with controls, for CHB in AD, AD + LBD, PSP and corticobasal degeneration, for BHB in AD + LBD and PSP, and SHB in AD + LBD and PSP were significantly increased. Regression analysis showed that CHBs were independently associated with higher Braak NFT stage, BHBs with LBD and TDP-43 pathology, SHBs with higher Braak NFT stage, PSP and argyrophilic grain disease and HBLs with MSA.

CONCLUSIONS

This study demonstrates that HBs are associated with diverse neurodegenerative diseases and shows that morphological types appear distinctively in various conditions.

Sudden unexpected death of a young adult due to subarachnoid hemorrhage associated with polyarteritis nodosa: Clinicopathological appearance and literature review

A 28-year-old male was found dead in his bedroom. There were no anomalies in his birth and medical history, and there was no family history of sudden unexpected death (SUD). Autopsy showed subarachnoid hemorrhage (SAH) with basilar top inflammatory pseudoaneurysm rupture accompanied by fibrinoid necrosis in the aneurysm wall. Active and healed arteritides in small- to medium-sized arteries were identified in the brain, heart, and systemic connective tissue, which was consistent with polyarteritis nodosa (PAN). Furthermore, pneumatosis cystoides intestinalis was observed in the ascending colon. Hepatitis B virus infection and antineutrophil nuclear antibodies were negative. Genetic investigation using whole-exome sequencing showed no mutations among autoinflammatory-related genes, including UBA1, MEFV, and ADA2. SAH due to rupture of a pseudoaneurysm formed by PAN was considered as the cause of death in the present case. Although myocardial ischemia linked to coronary arteritis is a recognized trigger for SUD in PAN, our study showed that rupture of inflammatory pseudoaneurysm in the cerebral artery can also cause SUD in younger subjects with PAN, even if prodromal symptoms are not evident before death.

Neuropathology of patients with preclinical or early clinical Alzheimer's disease with pathogenic PSEN1_p. L392V: Comparison of advanced siblings

INTRODUCTION

Neuropathological investigation of presymptomatic or early symptomatic presenilin-1 (PSEN1) mutation carriers in familial Alzheimer's disease (AD) is extremely scarce.

METHODS

We report the autopsy findings of brothers with familial AD. Case 1 is a 45-year-old man without obvious cognitive impairment, who committed suicide. Case 2 is a 57-year-old older brother of Case 1 with advanced AD symptoms, who died of hypothermia during wondering.

RESULTS

In both cases, abundant amyloid plaques positive for amyloid β (Aβ) were found throughout the brain. Progression of neuronal loss and increasing amount and extension of neurofibrillary tangle pathology were evident in Case 2. Genetic investigation revealed a PSEN1_p. L392V mutation in both cases.

DISCUSSION

The present study shows a possible neuropathological boundary between symptomatic and preclinical AD with pathogenic PSEN1 mutation. Additional clinicopathological investigation for familial AD-related mutation carriers may be significant to explore the association between familial AD and suicide.

Enterocolic granulomatous phlebitis associated with epidermal growth factor-containing fibulin-like extracellular matrix protein 1 deposition and focal amyloid properties: A case report

A woman in her 60s with rheumatoid arthritis was admitted with fever and abdominal pain. Laparoscopic examination with the differential diagnosis of peritoneal neoplasm and infection revealed granulomatous phlebitis in the resected greater omentum. Amorphous eosinophilic deposits observed in the resected tissue exhibited focal, weak positivity for Congo red but were strongly positive for thioflavin S, confirming their focal amyloid properties. Marked degeneration of elastic fibers was also evident. Electron microscopy revealed deposits around the affected elastic fibers. Immunohistochemistry revealed the deposition of epidermal growth factor-containing fibulin-like extracellular matrix protein 1 (EFEMP1) along with T-cell-predominant lymphocytic inflammation. The definitive diagnosis was granulomatous enterocolic lymphocytic phlebitis (ELP) associated with EFEMP1 deposition exhibiting focal amyloid properties (EFEMP1/AEFEMP1), supported by proteomics analysis. This type of vasculitis is similar to amyloid-β-related angiitis of the central nervous system. Thus, we speculate that granulomatous ELP also results from an immune response that recognizes EFEMP1/AEFEMP1 deposits as foreign material and attempts to remove them. Confirmation of EFEMP1/AEFEMP1 deposition with Congo red staining is challenging, particularly in the presence of inflammation, and warrants comprehensive evaluation.

Transthyretin-derived amyloid (ATTR) and sarcoidosis: Does ATTR deposition cause a granulomatous inflammatory response in older adults with sarcoidosis?

This study aimed to assess the frequency and association between transthyretin-derived (ATTR) amyloidosis and sarcoidosis in a large autopsy cohort including many cases of sudden cardiac death (SCD). We identified 73 sporadic ATTR amyloidosis cases and 11 sarcoidosis cases, among which we found two cases with concomitant ATTR amyloidosis and sarcoidosis (2.4% of all cases; 2.7% within the sporadic ATTR group). The first case involved a 92-year-old man who experienced SCD. In this patient's heart, we observed ATTR deposition and noncaseating epithelioid granulomas consistent with sarcoidosis. Focally, ATTR deposits and granulomas co-localized, with histiocyte phagocytosis of transthyretin-immunoreactive fragments. However, in most lesions, they were distributed independently. The second case was that of an 86-year-old woman who also experienced SCD. In this patient, we detected ATTR deposition in the heart and lung, while noncaseating epithelioid granulomas were only observed in the lung, liver, kidney, and thyroid. Furthermore, no co-localization of the two lesions was observed. Based on these findings, we concluded that the coexistence of ATTR amyloidosis and sarcoidosis was likely coincidental. Nevertheless, despite the rarity of the combination of these two diseases, it should be recognized as a potential cause of SCD, especially among elderly people.

The molecular spectrum of amyloid-beta (Aβ) in neurodegenerative diseases beyond Alzheimer's disease

This study investigated the molecular spectrum of amyloid-beta (Aβ) in neurodegenerative diseases beyond Alzheimer's disease (AD). We analyzed Aβ deposition in the temporal cortex and striatum in 116 autopsies, including Lewy body disease (LBD; N = 51), multiple system atrophy (MSA; N = 10), frontotemporal lobar degeneration-TDP-43 (FTLD-TDP; N = 16), and progressive supranuclear palsy (PSP; N = 39). The LBD group exhibited the most Aβ deposition in the temporal cortex and striatum (90/76%, respectively), followed by PSP (69/28%), FTLD-TDP (50/25%), and the MSA group (50/10%). We conducted immunohistochemical analysis using antibodies targeting eight Aβ epitopes in the LBD and PSP groups. Immunohistochemical findings were evaluated semi-quantitatively and quantitatively using digital pathology. Females with LBD exhibited significantly more severe Aβ deposition, particularly Aβ42 and Aβ43 , along with significantly more severe tau pathology. Furthermore, a quantitative analysis of all Aβ peptides in the LBD group revealed an association with the APOE-ε4 genotypes. No significant differences were observed between males and females in the PSP group. Finally, we compared striatal Aβ deposition in cases with LBD (N = 15), AD without α-synuclein pathology (N = 6), and PSP (N = 5). There were no differences in the pan-Aβ antibody (6F/3D)-immunolabeled deposition burden among the three groups, but the deposition burden of peptides with high aggregation capacity, especially Aβ43 , was significantly higher in the AD and LBD groups than in the PSP group. Furthermore, considerable heterogeneity was observed in the composition of Aβ peptides on a case-by-case basis in the AD and LBD groups, whereas it was relatively uniform in the PSP group. Cluster analysis further supported these findings. Our data suggest that the type of concomitant proteinopathies influences the spectrum of Aβ deposition, impacted also by sex and APOE genotypes.

Comprehensive pathological and genetic investigation of three young adult myotonic dystrophy type 1 patients with sudden unexpected death

OBJECTIVES

The mechanism and pathological substrate of arrhythmogenic events in dystrophic myopathy type 1 (DM1) have not been fully established, especially for patients without progression of motor and/or cardiac disability. Therefore, we aimed to clarify the pathological appearance and genetic factors, other than CTG repeats in DMPK, associated with sudden cardiac death in patients with DM1.

METHODS

A pathological investigation including the cardiac conduction system in the heart and whole-exome sequencing was conducted for three young adults (Patient 1; 25-year-old female, Patient 2; 35-year-old female, Patient 3; 18-year-old male) with DM1 who suffered sudden death.

RESULTS

Only Patient 1 showed abnormal electrocardiogram findings before death. The pathological investigation showed severe fibrosis of the atrioventricular conduction system in Patient 1 and severe fatty infiltration in the right ventricle in Patient 2. Several minimal necrotic/inflammatory foci were found in both patients. Patient 3 showed no significant pathological findings. A genetic investigation showed CORIN_p.W813* and MYH2_p. R793* in Patient 1, KCNH2_p. V794D and PLEC_p. A4147T in Patient 2, and SCN5A_p.E428K and SCN3B_ p.V145L in Patient 3 as highly possible pathogenic variants.

CONCLUSION AND RELEVANCE

The present study showed varied heart morphology in young adults with DM1 and sudden death. Synergistic effects of various genetic factors other than CTG repeats may increase the risk of sudden cardiac death in DM1 patients, even if signs of cardiac and skeletal muscle involvement are mild. Comprehensive genetic investigations, other than CTG repeat assessment, may be useful to estimate the risk of sudden cardiac death in DM1 patients.

Prevalence and Distribution of Lewy Pathology in a Homeless Population

BACKGROUND

The homeless population experience significant inequalities in health, and there is an increasing appreciation of the potential of lifestyle factors in the development of neurodegenerative diseases, including Parkinson's disease. We performed a study on the prevalence and distribution of pathological alpha-synuclein deposition throughout the central and peripheral nervous systems in a homeless population.

METHODS

Forty-four homeless individuals consecutively available for autopsy were recruited. Immunohistochemistry was performed using 5G4 antibody recognizing disease-associated forms of alpha-synuclein, complemented by phospho-synuclein antibody on autopsy tissues collected from 18 regions of the brain and spinal cord, as well as the right and left olfactory bulb, the cauda equina, the extramedullary portion of the vagus nerve, and 27 sites of peripheral organs.

RESULTS

The study cohort consisted of 38 males and 6 females, median age 58 years (range 32-67). Lewy-related pathology was present in the brains of three male cases. One showed Braak stage 2 (60 years old), and two stage 4 (56 and 59 years old). One of the Braak stage 4 cases had Lewy-related pathology in the spinal cord, the cauda equina, and the extramedullary portion of the vagus nerve. Examination of 27 sites of peripheral organs found that all three cases with Lewy-related pathology present in the brain were devoid of peripheral organ alpha-synuclein pathology. Multiple system-type alpha-synuclein pathology was not found.

CONCLUSION

Our study, representing a snapshot of the homeless population that came to autopsy, suggests that alpha-synuclein pathology is prevalent in the homeless supporting further study of this vulnerable population.

Distinct Molecular Signatures of Amyloid-Beta and Tau in Alzheimer's Disease Associated with Down Syndrome

Limited comparative data exist on the molecular spectrum of amyloid-beta (Aβ) and tau deposition in individuals with Down syndrome (DS) and sporadic Alzheimer's disease (sAD). We assessed Aβ and tau deposition severity in the temporal lobe and cerebellum of ten DS and ten sAD cases. Immunohistochemistry was performed using antibodies against eight different Aβ epitopes (6F/3D, Aβ38, Aβ39, Aβ40, Aβ42, Aβ43, pyroglutamate Aβ at third glutamic acid (AβNp3E), phosphorylated- (p-)Aβ at 8th serine (AβpSer8)), and six different pathological tau epitopes (p-Ser202/Thr205, p-Thr231, p-Ser396, Alz50, MC1, GT38). Findings were evaluated semi-quantitatively and quantitatively using digital pathology. DS cases had significantly higher neocortical parenchymal deposition (Aβ38, Aβ42, and AβpSer8), and cerebellar parenchymal deposition (Aβ40, Aβ42, AβNp3E, and AβpSer8) than sAD cases. Furthermore, DS cases had a significantly larger mean plaque size (6F/3D, Aβ42, AβNp3E) in the temporal lobe, and significantly greater deposition of cerebral and cerebellar Aβ42 than sAD cases in the quantitative analysis. Western blotting corroborated these findings. Regarding tau pathology, DS cases had significantly more severe cerebral tau deposition than sAD cases, especially in the white matter (p-Ser202/Thr205, p-Thr231, Alz50, and MC1). Greater total tau deposition in the white matter (p-Ser202/Thr205, p-Thr231, and Alz50) of DS cases was confirmed by quantitative analysis. Our data suggest that the Aβ and tau molecular signatures in DS are distinct from those in sAD.

An autopsy case of infective aortic aneurysm with Pasteurella multocida infection: clinicopathological appearance and a review of literatures

Here, we showed our clinicopathological findings of infected aortic aneurysm (IAA) with Pasteurella multocida, which is a Gram-negative coccobacillus and is part of the normal oral flora of many animals. The patient was a 76-year-old male animal owner with a history of diabetes mellitus, alcoholic liver damage, and laryngeal cancer. He died 16 days after admission without undergoing operation because of poor general condition. Autopsy showed saccular outpouching with loss of the existing aortic wall and marked neutrophilic infiltration in the suprarenal abdominal aorta. Rupture was not evident. A polymerase chain reaction assay using DNA extracted from formalin-fixed paraffin-embedded specimen of the aneurysmal wall detected the Pasteurella multocida gene, therefore we conclude that the present case was IAA of native aorta with Pasteurella multocida infection. A review of the literature showed that IAA of native aorta with Pasteurella multocida infection is opportunistic and that liver disorder, alcohol addiction, diabetes mellitus, and animal bite may increase its risk. On the other hand, aortic endograft infection with Pasteurella multocida frequently occurred without an immunocompromised state. Pasteurella multocida may be a distinct causative microorganism in IAA, and/or sepsis when the participant is an animal owner.

Argyrophilic grain disease is common in older adults and may be a risk factor for suicide: a study of Japanese forensic autopsy cases

BACKGROUND

Neuropathological diagnosis of argyrophilic grain disease (AGD) is currently based primarily on the combination of argyrophilic grain (AG) visualized using Gallyas-Braak silver staining, phosphorylated tau-positive pretangles, coiled bodies, and ballooned neuron detection. Although AGD is common in patients with dementia and/or prominent psychiatric symptoms, whether it is a distinct neurological disease entity or a by-product of the aging process remains unclear.

METHODS

In 1449 serial forensic autopsy cases > 40 years old (823 males and 525 females, aged 40-101 years, mean age 70.0 ± 14.1 years), we examined the frequency and comorbid pathology of AGD cases and investigated the clinical appearance by comparing those with non-AGD cases using the propensity score.

RESULTS

Of the 1449 cases, we detected 342 AGD cases (23.6%; mean age 79.7 years; 177 males and 165 females). The AGD frequency and stage increased with age (P < 0.001). Among AGD cases, 80 (23.4%) patients had dementia, and 51 (15.2%) had a history of psychiatric hospital visits. The frequency of suicide and history of psychiatric disorders were significantly higher in AGD cases than in AGD-negative cases, matched for age, sex, and comorbidity pathology, with a relative risk of suicide of 1.72 (1.30-2.26). The frequency of suicide was significantly higher in AGD cases than in non-AGD cases in female but not male cases. The relative risk of suicide increased to 2.27 (1.20-4.30) and 6.50 (1.58-26.76) in AGD patients with Lewy and progressive supranuclear palsy pathology, respectively, and decreased to 0.88 (0.38-2.10) in those with advanced AD pathology. In AGD cases, 23.4% had dementia; however, the difference was not significant after controlling for age, sex, and comorbid pathology.

CONCLUSION

Our study demonstrated that AGD is a significant and isolated risk factor for psychiatric hospital visits and suicide completion. In older adults, AGs may contribute to the progression of functional impairment of the limbic system, which leads to psychiatric disorders and suicide attempts.

Acute benzyl alcohol intoxication: An autopsy case report

INTRODUCTION

The main mechanism of death and the pathological appearance of cases of benzyl alcohol intoxication has not been fully investigated. Autopsy reports of cases of benzyl alcohol intoxication have not been published.

CASE PRESENTATION

A 24-year-old man was found in the state of cardiopulmonary arrest at a construction site. He had been performing paint stripping. He was immediately transferred to the hospital, but he did not recover. An autopsy showed focal coloring of the skin without any major caustic injury. A histopathological investigation showed vacuolar degeneration in the epidermis and dermo-epidermal junction, and severe erosion of the tracheal and bronchial mucosa. No pathological changes in the kidney were evident. A neuropathological investigation showed central chromatolysis of neuronal cells in pontine nuclei and grumose degeneration in the cerebellar dentate nucleus. The blood content of benzyl alcohol was 780.0 μg/mL.

LESSONS

Present case suggest that multiple pathways of exposure may be associated with more rapid progression in acute benzyl alcohol intoxication, and that early and/or severe involvement of the central nervous system rather than renal dysfunction may be associated with an early death.

Lack of difference between amyloid-beta burden at gyral crests and sulcal depths in diverse neurodegenerative diseases

AIMS

The aim of this study is to clarify whether there is a difference in amyloid-beta burden between gyral crests (GCs) and sulcal depths (SDs) in different neurodegenerative proteinopathies.

METHODS

We analysed the burden and distribution of amyloid-beta deposition in post-mortem brain samples from 138 autopsies, including Alzheimer's disease (n = 30), Down's syndrome (n = 11), Lewy body disease (LBD; n = 53), multiple system atrophy (n = 8) and progressive supranuclear palsy (n = 36). We applied quantitative amyloid-beta burden analysis to compare amyloid-beta deposition in both GCs and SDs. We also evaluated the prevalence of amyloid-beta plaques in both regions in samples exhibiting high or low amounts of amyloid-beta pathology.

RESULTS

Amyloid-beta burden was evaluated in 67 and 84 samples of the frontal and temporal cortices, respectively. We did not find significant differences in the amyloid-beta burden between GCs and SDs in these regions in any examined disease. In addition, amyloid-beta plaques were almost evenly distributed in both regions in cases with low amounts of amyloid-beta pathology. Females in the LBD group showed significantly higher amyloid-beta burden than males (temporal cortex, p < 0.01). Furthermore, only one LBD case showed SD-predominant deposition associated with the coarse-grained plaques.

CONCLUSIONS

We have shown that amyloid-beta is almost evenly distributed in both GCs and SDs in the frontal and temporal lobes from the early stage, in diverse neurodegenerative diseases. Sex may contribute to differences in the amyloid-beta burden. The coarse-grained plaque may show SD-predominant neuritic tau deposition that must be carefully distinguished from chronic traumatic encephalopathy-related SD tau pathology.

Pathological and Comprehensive Genetic Investigation of Autopsy Cases of Idiopathic Bradyarrhythmia

BACKGROUND

Idiopathic bradyarrhythmia is considered to be due to pathological degeneration of the cardiac conduction system (CCS) during aging. There appears to have been no comprehensive genetic investigations in patients with idiopathic bradyarrhythmia.Methods and Results: Ten autopsy cases with advanced bradyarrhythmia (6 men and 4 women; age: 70-94 years, 81.5±6.9 years; 5 cases each of sinus node dysfunction [SND] and complete atrioventricular block [CAVB]) were genetically investigated by using whole-exome sequencing. Morphometric analysis of the CCS was performed with sex-, age- and comorbidity-matched control cases. As a result, severe loss of nodal cells and distal atrioventricular conduction system were found in SND and CAVB, respectively. However, the conduction tissue loss was not significant in either the atrioventricular node or the proximal bundle of His in CAVB cases. A total of 13 heterozygous potential variants were found in 3 CAVB and 2 SND cases. Of these 13 variants, 4 were missense in the known progressive cardiac conduction disease-related genes: GATA4 and RYR2. In the remaining 9 variants, 5 were loss-of-function mutation with highly possible pathogenicity.

CONCLUSIONS

In addition to degenerative changes of selectively vulnerable areas in the heart during advancing age, the vulnerability of the CCS, which may be associated with "rare variants of small effect," may also be a contributing factor to the degeneration of CCS, leading to "idiopathic" bradyarrhythmia.

Calcifying pseudoneoplasm of the neuraxis (CAPNON) associated with neurenteric cyst. An autopsy case showing unusual fatal outcome

A 53-year-old man with a history of an untreated brain mass was taken to Toyama Prefectural Central Hospital by emergency transport. Computed tomography revealed an intracranial hypo-attenuated lesion exhibiting mass effect. Several calcified foci were observed around the lesion. His radiographical diagnosis was meningioma with calcification and edema. He suddenly showed tonic seizure after admission; therefore an emergency craniotomy was performed. However, he unfortunately died due to advanced cerebral edema. Microscopic findings of the surgically obtained materials were consistent with neurenteric cyst (NC). Intracranial hard masses were found adjacent to NCs, and the masses were composed of fibrous cartilage-like matrix with extensive linear calcification and the presence of surrounding round-to-oval epithelioid cells. Thus, calcifying pseudoneoplasm of the neuraxis (CAPNON) associated with NC was considered the most appropriate diagnosis of the present case. To the best of our knowledge, this is the first report of such a case. The present case suggests that delay of treatment might cause a poor outcome, at least in CAPNON associated with NC. Careful investigations, including the underlying pathology, may be essential when considering the etiology of CAPNON and its treatment strategies.

Pathological Appearance of a Case of Preclinical Multiple System Atrophy: A Comparison With Advanced Cases

We aimed to investigate the frequency of multiple system atrophy (MSA) in a large number of forensic autopsies and characterize the pathological appearance of preclinical MSA. We investigated a series of 1930 brains from forensic autopsies. In addition to performing immunohistochemistry for phosphorylated α-synuclein, the levels of 3 autonomic nervous system markers (catecholaminergic, serotonergic, and cholinergic) were used to assess the peripheral nerve (heart and superior cervical ganglion) and medulla oblongata. The results were compared to those of healthy control and Parkinson disease (PD) cases. Four cases (0.21%) were identified as having MSA. Cases 1-3 were symptomatic, and Case 4 was incipient; that is, although no neuronal loss was evident, the cerebellar dentate nucleus exhibited marked grumose degeneration. Immunohistochemistry revealed a marked reduction in autonomic nervous system marker levels expressed in the medulla; this reduction was more prominent in the 3 symptomatic MSA cases than in the PD case. The opposite occurred for the peripheral nerve. Case 4 exhibited mild cholinergic nerve reduction. Two cases showed possible significant pathological changes in the heart. Grumose degeneration, few oligodendroglial cytoplasmic inclusions without neuronal loss, and less reduction of autonomic nervous tissue were more prominent in the preclinical case than in symptomatic cases.

Patterns of Mixed Pathologies in Down Syndrome

Background: Down syndrome (DS) is frequently associated with Alzheimer’s disease (AD)-related neuropathological changes. There are few observations on the spectrum of mixed proteinopathies in DS patients. Objective: This study aimed to evaluate multiple disease-associated proteinopathies in a series of DS cases. Methods: We analyzed the distribution of neurodegenerative disease associated proteins in postmortem brain samples from 11 DS cases (6 females, median age 57, range 38–66 years). Sections were stained for phosphorylated tau, 3-repeat and 4-repeat tau, amyloid-β, alpha synuclein, phosphorylated TDP-43, and P62. A comprehensive anatomical mapping and staging were applied for all proteins. Results: Tau and amyloid-β pathology was prevalent in all cases and compatible with that typically seen in AD with some subtle deviations. Four of 11 cases presented with Lewy-related pathology (LRP). Two cases followed the Braak staging (stage 4 and 5) whereas 2 cases presented with an atypical distribution. Two cases showed limbic predominant age-related TDP-43 encephalopathy (LATE) (stage 1 and stage 2) neuropathologic change. Two cases exhibited aging-related tau astrogliopathy (ARTAG). Conclusion: In addition to subtle deviations from AD regarding the morphology of Aβ deposition and distribution of neuronal tau pathology, we find that the spectrum of mixed-pathologies in DS show distinctive features such as deviations from the Braak staging of LRP and that LATE neuropathologic change and ARTAG pathology can be seen in individuals younger than in sporadic AD cases. Our observations support the notion that DS has distinctive pathogenic pathways from sporadic AD.

Clinicopathologic Appearance of Advanced Ketoacidosis With Basal Vacuolation in Renal Tubules

CONTEXT.—

Basal vacuolization (BV) in renal tubules is a histopathologic hallmark of advanced ketoacidosis that enables us to retrospectively diagnose these cases.

OBJECTIVE.—

To clarify the pathologic background and serologic findings of ketoacidosis with BV, and to reveal the pathologic findings by each pathologic background.

DESIGN.—

We examined 664 serial autopsy cases. A systemic histopathologic examination and measurement of serum β-hydroxybutyrate concentration were performed for the cases with BV. The extent of steatosis and fibrosis in the organs and the degree of coronary artery stenosis were semiquantitatively investigated. Immunohistochemistry for adipophilin was also performed to analyze its usefulness for the pathologic diagnosis.

RESULTS.—

Basal vacuolization was found in 16 cases, all of which showed a pathologic serum β-hydroxybutyrate concentration. The main background of ketoacidosis was considered as alcohol abuse in 6 cases, diabetes in 5, malnutrition in 3, and hypothermia and infection in 1 case each. Severe hepatic fibrosis was observed only in the alcohol-abuser group. Moreover, cardiac steatosis was more severe in patients with possible alcohol abuse than in those with other causes. Immunohistochemistry for adipophilin showed immunoreactivity consistent with BV in 13 of 16 cases. There was no correlation between β-hydroxybutyrate concentration and either the postmortem or storage interval.

CONCLUSIONS.—

Basal vacuolization may be a useful finding for detecting ketoacidosis cases in a postmortem investigation. Serum β-hydroxybutyrate was a stable and reliable compound for the definitive diagnosis of ketoacidosis in such cases. The present study showed that pathologic changes in some organs may vary by each pathologic background of ketoacidosis with BV.

Effects of sporadic transthyretin amyloidosis frequently on the gallbladder and the correlation between amyloid deposition in the gallbladder and heart: A forensic autopsy-based histopathological evaluation

The aim of the study is to evaluate the clinicopathological features of cholecystic ATTR deposition in patients with cardiac involvement, investigate the correlation of amyloid deposition severity in the gallbladder and the heart, and compare its prevalence in the gallbladder and other organs. Fifty patients with sporadic ATTR amyloidosis were identified. Of these, we evaluated 15 patients who underwent gallbladder sampling accurately. Among 10 patients (67%) with cholecystic deposition, six exhibited detectable deposition in the hematoxylin and eosin-stained specimens, and all of them displayed obstructive vascular deposition (VD). The severity of gall bladder VD was statistically correlated with that of cardiac VD and atrial interstitial deposition (ID). Additionally, all patients exhibiting cholecystic ID displayed severe ventricular and atrial IDs. In visceral organs excluding the heart, amyloid deposition was commonly observed in the lungs (93%), followed by the gastrointestinal tract (47%-80%), liver (60%) and periosteal tissues (53%). The involvement of the gallbladder was prevalent and comparable to that of the gastrointestinal tract. Moreover, the severity of cholecystic deposition was correlated with that of cardiac deposition. Therefore, pathologists should be aware that sporadic ATTR amyloidosis is a common condition and should not be overlooked.

Two autopsy cases with injuries to the stomach following cardiopulmonary resuscitation

We herein report two autopsy cases with gastric injury associated with cardiopulmonary resuscitation (CPR). Case 1 was a 36-year-old woman who was found in cardiopulmonary arrest possibly caused by a fall from a height of 8 m. She received continuous manual chest compression with artificial ventilation while being transferred to the hospital. Autopsy revealed bruises on her left upper arm with a fracture to the left humerus and advanced pneumohemothorax that was associated with laceration of the left lung due to fracture of the dorsal left costa. Furthermore, complete rupture of the gastric wall (25 cm) was found without hemorrhage. Case 2 was an 85-year-old man found unconscious on the road. He had a history of oral anticoagulant administration, cognitive impairment, and gait disorder. He also received cardiac massage and manual artificial ventilation during CPR. Autopsy revealed severe head injury, possibly caused by a backward fall. His stomach was markedly dilated by air and a fresh intramural hematoma had extended into all layers of the stomach and adjacent omentum; however, injury of the abdominal wall was not evident. Histopathological investigation of the brain revealed advanced Alzheimer's disease and Lewy pathology, and the damaged neural tissue, which was positive for the amyloid precursor protein. We determined that the gastric injuries in both cases had been caused by CPR. We conclude that careful investigation is required for gastric injury cases to determine the etiology and correlation between gastric injury and cause of death when the victims receive CPR.

Clinicopathological features of clinically undiagnosed sporadic transthyretin cardiac amyloidosis: a forensic autopsy-based series

OBJECTIVE

To investigate the clinicopathological features of sporadic amyloid transthyretin (ATTR) amyloidosis.

METHODS

We evaluated 1698 serial Japanese forensic autopsy patients. The extent and amount of ATTR deposition in the 16 cardiac regions, including the conduction system, were semiquantitatively evaluated. Ward's hierarchical cluster analysis was applied to classify the cases into subgroups. Also, the relationship between ATTR and amyloid atrial natriuretic factor (AANF) was evaluated.

RESULTS

Forty-four cardiac ATTR amyloidosis patients (mean age 85.4 ± 5.7 years; 22 men) without history of hereditary polyneuropathy were identified (2.6% of all patients, 8.8% of those aged ≥80 years). All the 44 patients were not in the bedridden state and died-out-of-hospital scenarios. Of these, 10 (23%) were sudden death. Cluster analysis classified the patients into three groups (mild, atria-predominant and the severe deposition group). Amyloid deposition had already started simultaneously from each atrium and ventricle; however, the atrial septum and basilar ventricular septum were the sites that revealed the most frequent deposition. Also, a possible association between ATTR and AANF deposits was identified.

CONCLUSIONS

Sporadic ATTR amyloidosis patients might already be susceptible to a risk for sudden death even from an early-phase. Also, ATTR amyloid deposition in such cases might progress with a certain degree of regularity.

An autopsy case of pure nigropathy with TUBA4A nonsense mutation

We showed the results of pathological and genetic investigation for an autopsy case who was evaluated as longstanding Parkinson's disease (PD) in alive. Neuropathological investigation showed "pure nigropathy" without Lewy and tau pathology, and genetic analyses using next-generation sequencing detected novel TUBA4A nonsence mutation. Subsequent physiological study added to strength the hypothesis that the variant is pathogenic one. Present case showed TUBA4A is not only responsible gene for amyotrophic lateral sclerosis/frontotemporal dementia but also PD associated pure nigropathy. Also we found minimal but significant tau pathology high possibly associated with long-term deep brain stimulation in subthalamic nucleus.

Sex-dependent expression of prostatic markers and hormone receptors in cystic tumor of the atrioventricular node: A histopathological study of three cases

We pathologically investigated three autopsy cases of cystic tumor of the atrioventricular node (CTAVN) with sudden death. Case 1 was a 36-year-old woman without any clinical history. Case 2 was a 76-year-old man with an implanted pacemaker for complete atrioventricular block. Case 3 was a 45-year-old man with a history of first-degree AV block and sinus bradycardia. Microscopically, all three cases showed the bilayered structure of tumor glands and corpora amylacea in the glandular lumens. Immunohistochemically, the inner cells of the tumor glands were positive for cytokeratin CAM5.2, CEA, EMA, olfactomedin-4 and alpha-methylacyl-coenzyme A racemase; the outer cells were positive for p63 and cytokeratin high molecular weight. In Case 1, androgen receptor and estrogen receptor were negative; progesterone receptor was focally positive in both the inner and outer cells. In Case 2, androgen receptor showed intermediate positivity in the inner cells; estrogen receptor and progesterone receptor were positive in the outer cells. Positive expression of both prostate-specific antigen and prostate-specific acid phosphate were found in the inner cells of both male cases. Because CTAVN cells exhibit different degrees of the prostatic phenotype depending on the patient's sex, we believe that CTAVN may originate from urogenital sinus tissue in some cases.

Autopsy of a multiple lobar hemorrhage case with amyloid-β-related angiitis

A 92-year-old man died of multiple lobar hemorrhage with amyloid-β protein (Aβ)-related angiitis (ABRA) with an unusual pathological appearance. Although he had shown relatively rapid progressive dementia, starting 1 year before death, there was no detailed clinical investigation, and no immunosuppressive or anticoagulant therapy, because of his advanced age. The autopsy showed two lobar hemorrhagic lesions in the right parietal lobe and temporal lobes. Microscopically, almost all the brain's blood vessels showed cerebral amyloid angiopathy with many foci of transmural vasculitis. Infiltrating cells were predominantly CD8-positive T-lymphocytes, but we observed no granulomatous inflammation with appearance of multinucleated giant cells. We found fibrinoid necrosis in some blood vessels and disruption of these blood vessels in the arachnoid space-cerebral cortex junction in the hemorrhagic lesion at the temporal lobe. We also observed an unusual, neutrophil-predominant, abscess-like vasculitis in the subarachnoid space; almost all such unusual vasculitides were located at a short distance from the two lobar hemorrhagic lesions. Serum anti-neutrophil cytoplasmic myeloperoxidase and proteinase-3 antibodies were negative, and the genotype of the apolipoprotein E (ApoE) gene (ApoE) was ε2/ε3. Although we did not observe some of ABRA's typical histopathological findings, transmural and vascular destructive inflammation with Aβ deposition was consistent with ABRA. Vulnerability of blood vessels to fibrinoid necrosis might be associated with disruption of the relevant blood vessels, leading to lobar hemorrhage. ABRA exhibits various clinical and histopathological findings, depending on the patient's age, immune function status, treatment, and ApoE genotype. This is the first case and the oldest (92 years old) autopsy of ABRA associated with ApoE-ε2/ε3 genotype.

An autopsy case of sudden unexpected death with loxoprofen sodium-induced allergic eosinophilic coronary periarteritis

Although the cause of eosinophilic coronary periarteritis (ECPA) remains unclear, an allergic background is present in fewer patients than expected. A 50-year-old man with no history of allergy or symptoms suggestive of cardiac or respiratory disorders suddenly died shortly after oral administration of loxoprofen sodium. Autopsy showed eosinophilic coronary periarteritis in three main branches of the coronary arteries, characterized by eosinophil-predominant inflammation without fibrinoid necrosis or granulomatous change in the adventitia and its surroundings of the three main branches of the coronary arteries, in addition to the localized sign of bronchial asthma in the lung. Immunohistochemical examination showed that many mast cells positive for human mast cell tryptase were evident in the perivascular tissue containing peripheral nerve trunks. Whereas the blood concentration of loxoprofen sodium was within the therapeutic range, significant elevation of the serum histamine and tryptase levels was found. The present case suggests that eosinophilic coronary periarteritis may be caused by a type I allergic reaction in some patients and that loxoprofen sodium can trigger a life-threatening type I allergic reaction, including eosinophilic coronary periarteritis, leading to sudden unexpected death.

A fulminant case of classical Hodgkin lymphoma: A diagnostic dilemma of Epstein-Barr virus-positive large B-cell neoplasms

We report a fulminant case of classical Hodgkin lymphoma (CHL). The patient died only approximately 2 months after the onset of subjective symptoms. Autopsy specimens revealed atypical cells resembling Hodgkin and Reed-Sternberg (HRS) cells in a rich inflammatory background in various organs. There were marked, characteristic angiodestructive lesions from infiltrating HRS-like cells and numerous macrophages. The HRS-like cells were infected with Epstein-Barr virus (EBV), immunohistochemically positive for PAX5 and CD30, and negative for CD3, CD20, and ALK. Most B-cell markers other than PAX5 were negative, and the HRS-like cells also expressed cytotoxic molecules. Monoclonal rearrangement of immunoglobulin heavy chain was detected by PCR analysis. According to the 2016 WHO classification, we diagnosed mixed cellularity CHL. However, EBV-positive diffuse large B-cell lymphoma (DLBCL), not otherwise specified and EBV-positive B-cell lymphoma, unclassifiable with features intermediate between DLBCL and CHL were considered as differential diagnoses because both tumors are aggressive EBV-positive large B-cell neoplasms with reactive inflammatory cells and sometimes contains HRS-like cells. The clinical condition of the current case was closer to these two entities than to CHL. A diagnosis of EBV-positive large B-cell neoplasms was difficult because of overlapping morphological and immunohistochemical characteristics, but should be considered for prognosis.

Clinicopathological and Genetic Profiles of Cases with Myocytes Disarray-Investigation for Establishing the Autopsy Diagnostic Criteria for Hypertrophic Cardiomyopathy

Myocyte disarray of >10% in the heart is broadly accepted as a diagnostic pitfall for hypertrophic cardiomyopathy (HCM) at postmortem. The present study aims to propose an additional diagnostic criterion of HCM. Heart specimens from 1387 serial forensic autopsy cases were examined. Cases with myocyte disarray were extracted and applied to morphometric analysis to determine the amount of myocyte disarray. Comprehensive genetic analysis by using next-generation sequencing was subsequently applied for cases with myocyte disarray. Fifteen cases with myocyte disarray were extracted as candidate cases (1.1%, 11 men and 4 women, aged 48–94 years). In terms of the cause of death, only 2 cases were cardiac or possible cardiac death, and the other was non-cardiac death. Six cases showed myocyte disarray of >10% and 3 cases showed myocyte disarray of 5% to 10%. The other 6 cases showed myocyte disarray of <5%. Nine rare variants in 5 HCM-related genes (MYBPC3, MYH7, MYH6, PRKAG2, and CAV3) were found in 8 of 9 cases with myocyte disarray of >5%. The remaining 1 and 6 cases with myocyte disarray of <5% did not have any such variant. Myocyte disarray of >5% with rare variants in related genes might be an appropriate postmortem diagnostic criterion for HCM, in addition to myocyte disarray of 10%.

Acquired amegakaryocytic thrombocytopenia previously diagnosed as idiopathic thrombocytopenic purpura in a patient with hepatitis C virus infection

We report the first case of a patient with hepatitis C virus (HCV) infection and idiopathic thrombocytopenic purpura (ITP), who later developed acquired amegakaryocytic thrombocytopenia (AAMT), with autoantibodies to the thrombopoietin (TPO) receptor (c-Mpl). A 64-year-old woman, with chronic hepatitis C, developed severe thrombocytopenia and was diagnosed with ITP. She died of liver failure. Autopsy revealed cirrhosis and liver carcinoma. In the bone marrow, a marked reduction in the number of megakaryocytes was observed, while other cell lineages were preserved. Therefore, she was diagnosed with AAMT. Additionally, autoantibodies to c-Mpl were detected in her serum. Autoantibodies to c-Mpl are one of the causes of AAMT, acting through inhibition of TPO function, megakaryocytic maturation, and platelet formation. HCV infection induces several autoantibodies. HCV infection might also induce autoantibodies to c-Mpl, resulting in the development of AAMT. This mechanism may be one of the causes of thrombocytopenia in patients with HCV infection.

Human intestinal spirochetosis in Japanese patients aged less than 20 years: Histological analysis of colorectal biopsy and surgical specimens obtained from 479 patients

Human intestinal spirochetosis (HIS) is a condition in which spirochetes attach to and colonize the colorectal epithelium. To our knowledge, no comprehensive studies of HIS in young patient have been published in a developed country. This study aimed to determine the incidence and clinicopathological manifestations of HIS in Japanese patients aged less than 20 years. We retrospectively reviewed 3605 biopsy and 92 surgical specimens obtained from 479 patients admitted to Shinshu University Hospital between 1997 and 2014. All slides were reviewed independently by two pathologists to confirm the histological presence of spirochetes. Among 387 patients who underwent biopsy, the most common pathologic diagnosis was ulcerative colitis (12.6%, n = 49). Additionally, about half of the biopsy specimens showed non-specific, mildly inflamed mucosa (50.6%, n = 196); only one of these cases was HIS. On the other hand, among the surgical specimens, we found no cases of HIS. We concluded that the incidence of HIS in Japanese young patients was 0.2% (1/479 cases). The incidence of HIS in Japanese young patients was very low, and one HIS case was associated with colitis with abdominal pain.