[Muscular polyarteritis nodosa-a case-based review]. / Muskuläre Polyarteriitis nodosa ­ eine fallbasierte Übersichtsarbeit.

BACKGROUND: Myalgia is a common but unspecific set of symptoms that may be caused by orthopedic, neurological and internal medical conditions, often resulting in a diagnostic challenge. Muscular polyarteritis nodosa (PAN) is a rare differential diagnosis of myalgia with elevated serological inflammatory markers. OBJECTIVE: Based on three clinical cases and the literature this review describes the essential clinical and diagnostic features of muscular PAN. RESULTS: Muscular PAN typically presents with immobilizing myalgia confined to the lower limbs and elevated serological inflammatory markers but often normal creatine kinase (CK) levels. Contrast-enhanced magnetic resonance imaging of the affected muscles, which can often mimic myositis, and muscle biopsy provide the relevant histological findings that lead to the diagnosis of a vasculitis. CONCLUSION: With respect to own experiences and the reviewed literature, muscular PAN should be considered as a possible diagnosis in cases of myalgia with elevated inflammatory markers but normal CK levels and a lack of further symptoms typical for vasculitis.

Immune activation in amyloid-ß-related angiitis correlates with decreased parenchymal amyloid-ß plaque load.

BACKGROUND: Primary angiitis of the central nervous system (PACNS) is a rare but serious condition. A fraction of patients suffering from PACNS concurrently exhibit pronounced cerebral amyloid angiopathy (CAA) which is characterized by deposits of amyloid-ß (Aß) in and around the walls of small and medium-sized arteries of the brain. PACNS with CAA has been identified as a distinct disease entity, termed Aß-related angiitis (ABRA). Evidence points to an immune reaction to vessel wall Aß as the trigger of vasculitis. OBJECTIVE: To investigate whether the inflammatory response to Aß has (1) any effect on the status of immune activation in the brain parenchyma and (2) leads to clearance of Aß from brain parenchyma. METHODS: We studied immune activation and Aß load by quantitative immunohistochemical analysis in brain parenchyma adjacent to affected vessels in 11 ABRA patients and 10 matched CAA controls. RESULTS: ABRA patients showed significantly increased immune activation and decreased Aß loads in the brain parenchyma adjacent to affected vessels. CONCLUSION: Our results are in line with the hypothesis of ABRA being the result of an excessive immune response to Aß and show that this can lead to enhanced clearance of Aß from the brain parenchyma by immune-mediated mechanisms.

Disturbed energy metabolism and muscular dystrophy caused by pure creatine deficiency are reversible by creatine intake.

Creatine (Cr) plays an important role in muscle energy homeostasis by its participation in the ATP-phosphocreatine phosphoryl exchange reaction mediated by creatine kinase. Given that the consequences of Cr depletion are incompletely understood, we assessed the morphological, metabolic and functional consequences of systemic depletion on skeletal muscle in a mouse model with deficiency of l-arginine:glycine amidinotransferase (AGAT(-/-)), which catalyses the first step of Cr biosynthesis. In vivo magnetic resonance spectroscopy showed a near-complete absence of Cr and phosphocreatine in resting hindlimb muscle of AGAT(-/-) mice. Compared with wild-type, the inorganic phosphate/ß-ATP ratio was increased fourfold, while ATP levels were reduced by nearly half. Activities of proton-pumping respiratory chain enzymes were reduced, whereas F(1)F(0)-ATPase activity and overall mitochondrial content were increased. The Cr-deficient AGAT(-/-) mice had a reduced grip strength and suffered from severe muscle atrophy. Electron microscopy revealed increased amounts of intramyocellular lipid droplets and crystal formation within mitochondria of AGAT(-/-) muscle fibres. Ischaemia resulted in exacerbation of the decrease of pH and increased glycolytic ATP synthesis. Oral Cr administration led to rapid accumulation in skeletal muscle (faster than in brain) and reversed all the muscle abnormalities, revealing that the condition of the AGAT(-/-) mice can be switched between Cr deficient and normal simply by dietary manipulation. Systemic creatine depletion results in mitochondrial dysfunction and intracellular energy deficiency, as well as structural and physiological abnormalities. The consequences of AGAT deficiency are more pronounced than those of muscle-specific creatine kinase deficiency, which suggests a multifaceted involvement of creatine in muscle energy homeostasis in addition to its role in the phosphocreatine-creatine kinase system.

Efficient systemic therapy of rat glioblastoma by nanoparticle-bound doxorubicin is due to antiangiogenic effects.

The objective of this study was to investigate the therapeutic effects of doxorubicin bound to polysorbate-coated nanoparticles that had previously been shown to significantly enhance survival in the orthotopic rat 101/8 glioblastoma model. Tumor-bearing animals were subjected to chemotherapy using doxorubicin in solution (Dox-sol) or doxorubicin bound to polysorbate 80-coated poly(butyl cyanoacrylate) nanoparticles (Dox-np) injected intravenously on Days 2, 5 and 8 post tumor implantation. The antitumor effect was assessed on Days 10, 14 and 18 post tumor implantation. Tumors showed signs of malignancy including invasion of brain tissue, brisk mitotic activity, microvascular proliferation, necrosis and increased proliferation resembling human glioblastoma. Dox-np produced a considerably more pronounced antitumor effect exhibited as a reduced tumor size, lower proliferation, and a decreased necrotic area compared to Dox-sol and to untreated control groups. A drastic effect of Dox-np on vascularization indicated an antiangiogenic mode of action.

DNA methylation, transcriptome and genetic copy number signatures of diffuse cerebral WHO grade II/III gliomas resolve cancer heterogeneity and development.

BACKGROUND: Diffuse lower WHO grade II and III gliomas (LGG) are slowly progressing brain tumors, many of which eventually transform into a more aggressive type. LGG is characterized by widespread genetic and transcriptional heterogeneity, yet little is known about the heterogeneity of the DNA methylome, its function in tumor biology, coupling with the transcriptome and tumor microenvironment and its possible impact for tumor development. METHODS: We here present novel DNA methylation data of an LGG-cohort collected in the German Glioma Network containing about 85% isocitrate dehydrogenase (IDH) mutated tumors and performed a combined bioinformatics analysis using patient-matched genome and transcriptome data. RESULTS: Stratification of LGG based on gene expression and DNA-methylation provided four consensus subtypes. We characterized them in terms of genetic alterations, functional context, cellular composition, tumor microenvironment and their possible impact for treatment resistance and prognosis. Glioma with astrocytoma-resembling phenotypes constitute the largest fraction of nearly 60%. They revealed largest diversity and were divided into four expression and three methylation groups which only partly match each other thus reflecting largely decoupled expression and methylation patterns. We identified a novel G-protein coupled receptor and a cancer-related 'keratinization' methylation signature in in addition to the glioma-CpG island methylator phenotype (G-CIMP) signature. These different signatures overlap and combine in various ways giving rise to diverse methylation and expression patterns that shape the glioma phenotypes. The decrease of global methylation in astrocytoma-like LGG associates with higher WHO grade, age at diagnosis and inferior prognosis. We found analogies between astrocytoma-like LGG with grade IV IDH-wild type tumors regarding possible worsening of treatment resistance along a proneural-to-mesenchymal axis. Using gene signature-based inference we elucidated the impact of cellular composition of the tumors including immune cell bystanders such as macrophages. CONCLUSIONS: Genomic, epigenomic and transcriptomic factors act in concert but partly also in a decoupled fashion what underpins the need for integrative, multidimensional stratification of LGG by combining these data on gene and cellular levels to delineate mechanisms of gene (de-)regulation and to enable better patient stratification and individualization of treatment.

Sequence-dependent cross-resistance of combined radiotherapy plus BRAFV600E inhibition in melanoma.

INTRODUCTION: Treatment of patients with metastatic melanoma is hampered by drug-resistance and often requires combination with radiotherapy as last-resort option. However, also after radiotherapy, clinical relapses are common. METHODS & RESULTS: Our preclinical models indicated a higher rate of tumour relapse when melanoma cells were first treated with BRAFV600E inhibition (BRAFi) followed by radiotherapy as compared to the reverse sequence. Accordingly, retrospective follow-up data from 65 stage-IV melanoma patients with irradiated melanoma brain metastases confirmed a shortened duration of local response of mitogen-activated protein kinase (MAPK)-inhibitor-pretreated compared with MAPK-inhibitor-naïve intracranial metastases. On the molecular level, we identified JARID1B/KDM5B as a cellular marker for cross-resistance between BRAFi and radiotherapy. JARID1Bhigh cells appeared more frequently under upfront BRAFi as compared with upfront radiation. JARID1B favours cell survival by transcriptional regulation of genes controlling cell cycle, DNA repair and cell death. CONCLUSION: The level of cross-resistance between combined MAPK inhibition and radiotherapy is dependent on the treatment sequence. JARID1B may represent a novel therapy-overarching resistance marker.

Allelic losses at 1p, 9q, 10q, 14q, and 22q in the progression of aggressive meningiomas and undifferentiated meningeal sarcomas.

Meningiomas are usually benign tumors; however, they can recur after surgical resection and occasionally show histological progression to a higher malignancy grade. Five such rare cases of aggressively recurring meningiomas were present in our departmental cohort of 923 primary meningeal neoplasms operated over a 17-year period. Four other aggressively recurring meningeal tumors with a very similar clinical and histomorphological appearance (three undifferentiated meningeal sarcomas, one hemangiopericytoma) was also included in this study. We investigated whether disease progression can be traced by genetic alterations and whether a pattern of genetic alterations is specific for meningiomas. A total of 40 specimens from primary tumors and multiple recurrences of the nine patients were analyzed with 26 polymorphic allelic markers for deletions on 1p, 1q, 9q, 10q, 14q, and 22q. Loss of heterozygosity (LOH) at 22q was observed in all meningiomas cases at the earliest time point analyzed. Allelic loss at 1p was seen in the original tumor in two cases and upon meningioma recurrence in two others. Deletion on 10q occurred during tumor progression in two cases, and on 9q and 14q in one case. While allelic loss at 22q appears to be an early event in aggressive meningioma disease, there is a clear correlation of further deletions on chromosome arms 1p, 9q, 10q, and 14q with histopathological and clinical progression, as shown in these intraindividual trackings. None of these genetic findings were present in the non-meningiomatous meningeal tumors, indicating that meningothelial cells have their own lineage-specific genetic pathways towards clinical malignancy.

Post-traumatic meningitis: histomorphological findings, postmortem microbiology and forensic implications.

Infections of the leptomeninges with the infectious agent gaining access to the intracranial compartment by traumatic means are termed post-traumatic. In cases with fatal outcome, the manner of death has to be classified as non-natural. Six cases of post-traumatic meningitis as the cause of death from the archives of the Institute of Legal Medicine in Hamburg, Germany with histological and microbiological investigations are presented. There were all males, age varying between 24 and 90 years (mean 58 years); range of the interval between original trauma and beginning of symptoms was 2 days up to 8 years; in 50% of the cases meningeal swabs yielded Streptococcus pneumoniae. Findings concerning origin and mechanism of post-traumatic meningitis as well as microbiological studies are compared with selected cases from the literature.

Skin and soft tissue artifacts due to postmortem damage caused by rodents.

Five cases of postmortem bite-injuries inflicted by rodents are presented (five males between 41 and 89 years; three cases caused by mice, one case by rats, one case of possible mixed rodent activity by rats and mice). The study presents a spectrum of phenomenological aspects of postmortem artifacts due to rodent activity to fresh skin and soft tissue: the majority of the injuries have a circular appearance. The wound margins are finely serrated with irregular edges and circumscribed 1-2 mm intervals within, partly showing protruding indentations up to 5 mm. Distinct parallel cutaneous lacerations deriving from the biting action of the upper and lower pairs of the rodents incisors are diagnostic for tooth marks of rodent origin but cannot always be found. No claw-induced damage can be found in the skin beyond the wound margins. Areas involved in the present study were: exposed and unprotected parts of the body, such as eyelids, nose and mouth (representing moist parts of the face); and the back of the hands. Postmortem rodent activity may occasionally be expected on clothed and therefore protected parts of the body. The phenomenon of postmortem rodent activity to human bodies can be found indoors especially under circumstances of low socioeconomic settings; outdoors this finding is particularly observed among fatalities among homeless people.

[Vitality and possible causes of punctate hemorrhages in the lower brain stem of a burned corpse]. / Zur Frage der Vitalität und möglichen Ursachen von punktförmigen Blutungen im unteren Hirnstamm bei einer Brandleiche.

The case under discussion of a burn victim with dot haemorrhages into the caudal brain stem confirms other observations which have only rarely been published that these dot haemorrhages are not necessarily the sequelae of an intra vitam trauma. A reliable assessment of such cases demands a comprehensive pathologic and if possible neuropathologic autopsy including follow-up investigation considering police inquiry.

[Differential diagnostic aspects of forensically relevant findings in the brain stem]. / Differentialdiagnostische Aspekte forensisch relevanter Befunde im Hirnstamm.

Because of the extreme dense accumulation of vital structures (compared with other regions of the central nervous system), in the brainstem even small lesions may cause serious clinical symptoms. Judging the forensic relevance of macroscopically visible lesions requires the knowledge of the respective possible diagnosis. As shown in three case reports (67 years, teleangiectasis; 35 years, cavernoma; 49 years, secondary hemorrhage following trauma) this demands apart from the knowledge of the normal and pathological anatomy of the brainstem always the use of histological methods.

Skeletal spread of an anaplastic astrocytoma (WHO grade III) and preservation of histopathological properties within metastases.

BACKGROUND: The incidence of extraneural metastases of glioma is low. Metastases occur at different sites and, infrequently, as diffuse bone marrow infiltration. Direct contact of a glioma with extrameningeal tissues might be a reason for extraneural metastases. However, the role of haematogenous spread remains unclear. METHODS: We report on a young patient who suffered from a left frontal anaplastic WHO grade III astrocytoma, which was treated with gross total resection and irradiation (60 Gy). No local relapse occurred during the following course, but a diffuse infiltration of the bone marrow was diagnosed 12 months after the initial diagnosis. The patient died 6 months later, as a result of hypercalcaemia and pancytopenia. The histopathological properties of the tumour and its bone metastases were analysed, as well as the mutations of the isocitrate dehydrogenase 1 gene (IDH1). To study the route of tumour dissemination, the peripheral blood of the patient was analysed for circulating tumour cells (CTCs). RESULTS: This study describes a rare case of an extraneurally metastasised WHO grade III anaplastic astrocytoma. The occurrence of bone marrow infiltration coinciding with the finding of a stable intracranial tumour is a notably unusual situation. The properties of the primary tumour were maintained within the metastases in our patient. No CTCs were found in the peripheral blood at one random time point after the diagnosis of bone metastases. CONCLUSIONS: Despite young patient age, a stable intracranial course with a single location and mutations in the IDH1 gene, the patient's overall survival was short at 18 months after diagnosis. This finding illustrates the therapeutic dilemma in patients with bone marrow involvement complicating the use of alkylating agents, such as temozolomide. Repeated and systematic blood sampling in a large cohort of patients is needed for the detection of CTCs in glioma patients with systemic tumour spread. Future studies investigating how intrinsic factors in glioma cell biology cause rare metastases in these tumours are needed.

Diagnostic and therapeutic considerations for "mycotic" cerebral aneurysms: 2 case reports and review of the literature.

OBJECTIVE: Cerebral aneurysms of an infectious etiology, so-called "mycotic" aneurysms, are rare neurovascular pathologies. Primary treatment may be targeted on the aneurysm, but care has to be driven by the underlying pathology to prevent an often fatal clinical course with a mortality rate reaching 90%. 2 case reports are presented, and the diagnostic and therapeutic issues outlined by reviewing the literature. CASE REPORT: A 33-year-old female was admitted to our hospital with a sudden left-sided hemiparesis following a 3-week history of fever. An atypical intracerebral hemorrhage of the right parietal lobe due to a ruptured aneurysm of the distal middle cerebral artery (MCA) was diagnosed. Blood cultures containing Streptococcus sanguinus were the only finding for an infectious origin. Antibiotic therapy was started, followed by neurosurgical evacuation of the hematoma and clipping of the aneurysm. In a second case, endovascular coiling was the choice of treatment in a 38-year-old male presenting with a distal bifurcation aneurysm of the frontal MCA insular branch. An aortic valve replacement had been previously performed due to a congenital heart condition. The primary site of infection remained unclear and a 4-week course of broad-spectrum antibiotics was given intravenously. DISCUSSION: Cerebral aneurysms far distal to the usual sites of congenital aneurysms, organisms in blood chemistry, endocarditis, symptoms of infection, atypically located intracerebral hemorrhages, and young patients with immunodeficiency are strong factors for an infectious aneurysm. Cerebral angiography is mandatory to exclude aneurysms at other sites and early targeted antimicrobial treatment is crucial in these cases. Elimination of the aneurysm itself should be evaluated carefully because treating these aneurysms remains challenging compared to the ordinary group of cerebral aneurysms. Reconstructive procedures without sacrificing the parent artery often fail due to the fusiform and fragile aneurysm wall. CONCLUSION: Cerebral aneurysms of an infectious origin often have a disastrous clinical course in which morbidity and mortality can be reduced by early diagnosis, appropriate antimicrobial therapy, and aneurysm elimination by an experienced team. Apart from the initial treatment, major attention should be focused on a thorough follow-up to confirm complete cure of the primary site of infection.

Dementia and leukoencephalopathy due to lymphomatosis cerebri.

Lymphomatosis cerebri (LC) is a rare variant of primary central nervous system lymphoma (PCNSL). Clinically, the disease typically presents with a rapidly progressive dementia and unsteadiness of gait. Its presentation on cerebral MRI, which is characterised by diffuse leukoencephalopathy without contrast enhancement, often causes diagnostic confusion1 with suspected diagnoses ranging from Binswanger's disease to leukoencephalopathy or encephalomyelitis. Here we report a patient with subacute dementia and diffuse bilateral white matter changes in the cerebral hemispheres and additional involvement of the brainstem, basal ganglia and thalamus on MRI. Initially, she was considered to suffer from an autoimmune encephalitis, transiently responded to immunosuppression but then developed multiple solid appearing cerebral lymphomas.

Age-dependent normal values of T2* and T2' in brain parenchyma.

BACKGROUND AND PURPOSE: Physiologic age-related T2* and T2' values are required as reference for comparison with disease-related deviations. In our study, T2* and T2' values (T2 values as control) were determined with MR imaging in healthy subjects to determine standard values and investigate age-related changes. MATERIALS AND METHODS: Data of 50 patients without intraparenchymal pathology and 10 acute stroke patients who underwent MR imaging including a T2 and T2* sequence with 3 echotimes were included. After calculation of T2*, T2', and T2 maps, the values of gray matter (GM) and white matter (WM) for each hemisphere were measured in 6 distinct regions of interest (ROIs). RESULTS: There was a negative correlation between age and T2* values in the caudate nucleus (r = -0.34 Pearson correlation; P = .001) and lentiform nucleus (r = -0.67; P = .001) and a positive correlation in the occipital (r = 0.41; P = .001) and subcortical (r = 0.45; P = .001) WM. An age dependency for T2' values was only found for the caudate (r = -0.35; P = .001) and lentiform nucleus (r = -0.69; P = .001). T2' values in acute stroke were lower than normal in all patients with stroke. CONCLUSION: Decrease in T2' and T2* values in GM and increase of T2* values in WM correlate with the progress of brain aging. Explanations for decreasing T2' and T2* values include iron deposition in the caudate and lentiform nucleus. In contrast to T2* values, there is no association of T2' values with the degree of leukoaraiosis. These age-dependent values can be used as a reference in neurovascular diseases and for the discussion of functional MR imaging data.

Fatal methanol intoxication with different survival times--morphological findings and postmortem methanol distribution.

Three corresponding cases of fatal methanol intoxication with different survival times were investigated ante-mortem and postmortem. Ante-mortem serum methanol concentrations were determined during treatment in hospital for 4 days. Furthermore, postmortem distribution of methanol in various tissues and fluids was measured after autopsy. Morphological and toxicological findings are discussed based on the literature. The morphological findings correlated with the different survival times. The results of the toxicological analyses were partly in keeping with previously published data. Interestingly, very high methanol levels were determined in brain with very low concentrations in femoral venous blood. These results may have implications for postmortem toxicological analysis, brain death diagnosis and organ explanation for transplantation.

Cerebellar atrophy following mild head injury in a 4-year-old girl.

Cerebellar atrophy following severe head injury in infants has been described in imaging studies. We report the case of a 4-year-old girl who died of accidental hypothermia. Three weeks before, she had sustained head injury after falling on the back of her head with linear fracture of the occipital bone. Neuropathological examination of the girl's brain revealed cerebellar atrophy with specific loss of Purkinje cells. We present findings of detailed neuropathological studies and discuss possible mechanisms of posttraumatic cerebellar atrophy. To the best of our knowledge, cerebellar atrophy following mild head injury in man has not been described morphologically so far.