Etiology and pathogenesis of adverse drug reactions

In clinical routine, adverse drug reactions (ADR) are common, and they should be included in the differential diagnosis in all patients undergoing drug treatment. Only part of those ADR are immune-mediated hypersensitivity reactions and thus true drug allergies. Far more common are non-immune-mediated ADR, e.g. due to the pharmacological properties of the drug or to the individual predisposition of the patient (enzymopathies, cytokine dysbalance, mast cell hyperreactivity). In true drug allergiesT cell- and immunoglobulin E (lgE)-mediated reactions dominate the clinical presentation. T cell-mediated ADR usually have a delayed appearance and include skin eruptions in most cases. Nevertheless, it should not be forgotten that they may involve systemic T cell activation and thus take a severe, sometimes lethal turn. Clinical danger signs are involvement of mucosal surfaces, blistering within the exanthematous skin areas and systemic symptoms, e.g. fever or malaise. Drug presentation via antigen-presenting cells to T cells can either involve the classical pathway of haptenization of endogenous proteins or be directly mediated via noncovalent binding to immune receptors (MHC molecules or T cell receptors), the so-called p-i concept. Flare-up reactions during the acute phase of T cell-mediated ADR should not be mistaken for true drug allergies, as they only occur in the setting of a highly activated T cell pool. IgE-mediated ADR are less frequent and involve mast cells and/or basophils as peripheral effector cells. Recent data suggest that certain patients with drug allergy have a preexistent sensitization although they have never been exposed to the culprit drug, probably due to cross-reactivity. Thus, allergic drug reactions on first encounter are possible. In general, the extent of cross-reactivity is higher in IgE-compared to T cell-mediated ADR. Based on a specific ethnic background and only for severe T cell-mediated ADR to certain drugs, a strong HLA association has been established recently.

Etiology and symptoms of severe hypokalemia in emergency department patients

To investigate the prevalence, etiology, and symptoms of severe hypokalemia in patients presenting to the emergency department.

Etiology and management of recurrent parotid pleomorphic adenoma

The objective of this review study was to encompass the relevant literature and current best practice options for this challenging, sometimes incurable problem. The source of the data was Ovid MEDLINE from 1946 to 2014. Review methods consisted of articles with clinical correlates. The most important cause of recurrence is enucleation with rupture and incomplete tumor excision at operation. Incomplete pseudocapsule, extracapsular extension, pseudopods of pleomorphic adenoma tissue, and satellite pleomorphic beyond the pseudocapsule are also likely linked to recurrent pleomorphic adenoma. Most recurrent pleomorphic adenoma are multinodular. Magnetic resonance imaging is the imaging study of choice for recurrent pleomorphic adenoma. Nerve integrity monitoring may reduce morbidity for recurrent pleomorphic adenoma. Treatment of recurrent pleomorphic adenoma must be individualized. Total parotidectomy, given the multicentricity of recurrent pleomorphic adenoma, is appropriate in many patients, but may be inadequate to control recurrent pleomorphic. There is accumulating evidence from retrospective series that postoperative radiation therapy results in significantly better local control. LEVEL OF EVIDENCE NA Laryngoscope, 2014.

[Dens invaginatus. Review of the literature and diagnostic and therapeutic guidelines]

Dens invaginatus is a clinically relevant malformation of teeth resulting from an infolding of enamel and dentine into the dental structure during tooth formation, hence the former denomination "dens in dente". The dens invaginatus shows multiple morphological variations of crown and root formation. This frequently leads to caries, pulpal and periodontal involvement with necrosis and loss of attachment. Therefore, early diagnosis and prevention are of utmost importance. Due to the complexity of the malformation, treatment options in former days were limited. This article presents a profound review of the literature regarding etiology, epidemiology and histology. It discusses clinical appearance and diagnosis and it provides guidelines for decision-making and treatment of invaginated teeth.

Prognostic and diagnostic value of EEG signal coupling measures in coma.

OBJECTIVE Our aim was to assess the diagnostic and predictive value of several quantitative EEG (qEEG) analysis methods in comatose patients. METHODS In 79 patients, coupling between EEG signals on the left-right (inter-hemispheric) axis and on the anterior-posterior (intra-hemispheric) axis was measured with four synchronization measures: relative delta power asymmetry, cross-correlation, symbolic mutual information and transfer entropy directionality. Results were compared with etiology of coma and clinical outcome. Using cross-validation, the predictive value of measure combinations was assessed with a Bayes classifier with mixture of Gaussians. RESULTS Five of eight measures showed a statistically significant difference between patients grouped according to outcome; one measure revealed differences in patients grouped according to the etiology. Interestingly, a high level of synchrony between the left and right hemisphere was associated with mortality on intensive care unit, whereas higher synchrony between anterior and posterior brain regions was associated with survival. The combination with the best predictive value reached an area-under the curve of 0.875 (for patients with post anoxic encephalopathy: 0.946). CONCLUSIONS EEG synchronization measures can contribute to clinical assessment, and provide new approaches for understanding the pathophysiology of coma. SIGNIFICANCE Prognostication in coma remains a challenging task. qEEG could improve current multi-modal approaches.

Definition and diagnostic criteria of sleep-related hypermotor epilepsy

The syndrome known as nocturnal frontal lobe epilepsy is recognized worldwide and has been studied in a wide range of clinical and scientific settings (epilepsy, sleep medicine, neurosurgery, pediatric neurology, epidemiology, genetics). Though uncommon, it is of considerable interest to practicing neurologists because of complexity in differential diagnosis from more common, benign sleep disorders such as parasomnias, or other disorders like psychogenic nonepileptic seizures. Moreover, misdiagnosis can have substantial adverse consequences on patients' lives. At present, there is no consensus definition of this disorder and disagreement persists about its core electroclinical features and the spectrum of etiologies involved. To improve the definition of the disorder and establish diagnostic criteria with levels of certainty, a consensus conference using formal recommended methodology was held in Bologna in September 2014. It was recommended that the name be changed to sleep-related hypermotor epilepsy (SHE), reflecting evidence that the attacks are associated with sleep rather than time of day, the seizures may arise from extrafrontal sites, and the motor aspects of the seizures are characteristic. The etiology may be genetic or due to structural pathology, but in most cases remains unknown. Diagnostic criteria were developed with 3 levels of certainty: witnessed (possible) SHE, video-documented (clinical) SHE, and video-EEG-documented (confirmed) SHE. The main research gaps involve epidemiology, pathophysiology, treatment, and prognosis.

Diagnostic performance and accuracy of 3-D spoiled gradient-dual-echo MRI with water- and fat-signal separation in liver-fat quantification: comparison to liver biopsy

To prospectively evaluate a 3-dimensional spoiled gradient-dual-echo (3D SPGR-DE) magnetic resonance imaging (MRI) sequence for the qualitative and quantitative analysis of liver fat content (LFC) in patients with the suspicion of fatty liver disease using histopathology as the standard of reference.

Lack of social support in the etiology and the prognosis of coronary heart disease: a systematic review and meta-analysis

To conduct a systematic review and meta-analysis on the relevance of low social support for the development and course of coronary heart disease (CHD).

Clinical aspects, diagnostic challenges and management of patients with neuroendocrine tumors (NETs)

Neuroendocrine tumor (NET) entities are rare malignancies. Higher awareness and improved diagnostic methods have led to an increasing incidence of these diseases, and most oncologists deal with such patients in their daily practice. The symposium on NETs that was held in Merano (Italy) in October 2009 was organized by the German-speaking European School of Oncology (dESO) and gathered specialists from different disciplines of transalpine countries to bring together experiences and observations regarding these tumors. The goal of the meeting and of this review was to illustrate both well- and poorly differentiated NETs and to encourage interdisciplinary approaches.

A role for GRK2 in myocardial ischemic injury: indicators of a potential future therapy and diagnostic

Morbidity and mortality of myocardial infarction remains significant with resulting left ventricular function presenting as a major determinant of clinical outcome. Protecting the myocardium against ischemia reperfusion injury has become a major therapeutic goal and the identification of key signaling pathways has paved the way for various interventions, but until now with disappointing results. This article describes the recently discovered new role of G-protein-coupled receptor kinase-2 (GRK2), which is known to critically influence the development and progression of heart failure, in acute myocardial injury. This article focuses on potential applications of the GRK2 peptide inhibitor βARKct in ischemic myocardial injury, the use of GRK2 as a biomarker in acute myocardial infarction and discusses the challenges of translating GRK2 inhibition as a cardioprotective strategy to a possible future clinical application.

Femoroacetabular cam-type impingement: diagnostic sensitivity and specificity of radiographic views compared to radial MRI

To retrospectively assess the diagnostic sensitivity of 45° Dunn view and cross-table lateral radiographs for the assessment of cam deformity by comparison with radial MRI.

MR defecography in patients with dyssynergic defecation: spectrum of imaging findings and diagnostic value

We describe the spectrum of findings and the diagnostic value of MR defecography in patients referred with suspicion of dyssynergic defecation.