Successful Long-Term Prophylactic Treatment With Subcutaneous C1 Esterase Inhibitor in a Patient With Hereditary Angioedema.

BACKGROUND: Hereditary angioedema (HAE) patients suffer from recurrent swellings. Current standard therapy consists of C1 esterase inhibitor (C1-INH) and bradykinin receptor B2 antagonists. Severe courses require prophylactic treatment. For such patients, it has been demonstrated that the intravenous (IV) administration of C1-INH [C1-INH(IV)] is safe and effective. A new prophylactic option is subcutaneous (SC) treatment with C1-INH. METHODS AND CASE: We present the case of an HAE patient placed on prophylactic C1-INH(IV) therapy due to frequent attacks when managed with on-demand therapy. An implanted port allowed the periodical and safe application of medication until the device was explanted due to an infection. Due to the poor venous access, repeated IV application failed. Therefore, we began a SC treatment with 1500 IU C1-INH [C1-INH(SC)] as long-term prophylaxis and analyzed the clinical course over 16 months. RESULTS: Under the SC prophylaxis, the number of attacks were reduced to 1/month in comparison to 4.33/month with no prophylactic treatment and 1.83/month with C1-INH(IV). No severe attacks and no attack within the upper airway occurred over the 16 months of C1-INH(SC) treatment. As a result, quality of life improved, as measured by the Angioedema quality of life questionaire (AE-QoL). CONCLUSION: Self-administered SC prophylactic use of C1-INH over a period of 16 months seems to be a well tolerated and efficient. The patient's quality of life improved, and by learning self-application, the patient gained independence.

The Influence of ACE Inhibition on C1-Inhibitor: A Biomarker for ACE Inhibitor-Induced Angioedema?

AIMS: Angioedema is a rare side effect of angiotensin-converting enzyme (ACE) inhibitors. It remains unclear why it is only induced in a few patients taking ACE inhibitors, often after a long period of uneventful treatment. The aim of this study was to analyze the influence of ACE inhibitor treatment on C1-inhibitor (C1-INH) levels. METHODS: Captopril (5 mg/25 mg) was added to blood samples of 5 healthy subjects. C1-INH levels were measured before and after incubation for 180 min. The second section of the study was done with 17 patients who received therapy with an ACE inhibitor for the first time. C1-INH levels were measured before ACE inhibitor treatment, 24 h after first drug administration, and 4 weeks later. RESULTS: After incubation of blood samples with 5 mg captopril, there was no detectable change in C1-INH levels. After incubation with 25 mg, C1-INH activity was decreased by an average of 29% and the C1-INH concentration was decreased by an average of 0.06 g/L. In the second study section, inconsistent effects on C1-INH levels were detected. In the majority of patients, 24 h after the first ACE inhibitor administration C1-INH activity was tending to be increased. CONCLUSIONS: A dose-dependent effect on C1-INH levels in captopril-incubated blood samples of healthy test persons was shown. In patients with new ACE inhibitor treatment, heterogeneous reactions of C1-INH values were detected. Larger studies are needed over a longer period of time to find correlations between the effect of ACE inhibitor therapy on C1-INH levels and the clinical course/development of side effects.

Thrombosis of the internal jugular vein in the ENT-department - Prevalence, causes and therapy: A retrospective analysis.

OBJECTIVE: Less than 5% of deep vein thrombosis is due to thrombosis of the internal jugular vein. Genetic, malignant or inflammatory underlying diseases as well as insertion of venous catheters can be responsible for this pathology. Due to its rare occurrence, it is difficult to find systematic research about thrombosis of the internal jugular vein. METHODS: We performed a systematic analysis of present patient data from our ENT department with the electronic patient record considering the period from 2012-2017. Search terms were "thrombosis" and "jugular internal vein". We identified 41 patients with the requested diagnosis and performed further analysis of the cases. Internal jugular vein thrombosis was diagnosed in all patients using Duplex sonography and/or CT/MR angiography. RESULTS: Paraneoplastic thrombosis was found in 22/41 patients (54%), in 15 of the 22 (68%), the tumor was located in the ENT region. Two out of seven (29%) of the patients with tumor entities outside the head and neck region had thrombosis of the internal jugular vein as the first symptom of the disease. Another 14/41 patients (34%) had underlying inflammatory diseases - mostly streptococci-associated - for example a cervical abscess. In two patients, insertion of a central-venous catheter was causal, in three patients we could not find any reason for the development of thrombosis. CONCLUSION: To diagnose the rare and often asymptomatic thrombosis of the internal jugular vein, ultrasound of the cervical region should always include vascular imaging. Thrombosis of the internal jugular vein results mostly paraneoplastic or due to inflammation/abscess. It can be the first symptom of a malignant primary disease and always requires detailed diagnostic clarification. LEVEL OF EVIDENCE: 4.

Angioedema.

BACKGROUND: Acute angioedema of the upper airways can be life-threatening. An important distinction is drawn between mast-cell-mediated angioedema and bradykinin-mediated angioedema; the treatment of these two entities is fundamentally different. METHODS: This review is based on pertinent articles retrieved by a selective search in PubMed and on guidelines concerning the treatment of angioedema. The authors draw on their own clinical experience in their assessment of the literature. RESULTS: In the emergency clinical situation, the most important information comes from accompanying manifestations such as itching and urticaria and from the patient's drug history and family history. When angioedema affects the head and neck, securing the upper airways is the highest priority. Angioedema is most commonly caused by mast-cell mediators, such as histamine. This type of angioedema is sometimes accompanied by urticaria and can be effectively treated with antihistamines or glucocorticoids. In case of a severe allergic reaction or anaphylaxis, epinephrine is given intramuscularly in a dose that is adapted to the patient's weight (150 µg for body weight >10 kg, 300 µg for body weight >30 kg). Bradykinin-mediated angioedema may arise as either a hereditary or an acquired tendency. Acquired angioedema can be caused by angiotensin converting enzyme (ACE) inhibitors and by angiotensin II receptor blockers. Bradykinin-mediated angioedema should be treated specifically with C1-esterase inhibitor concentrates or bradykinin-2 receptor antagonists. CONCLUSION: Angioedema of the upper airways requires a well-coordinated diagnostic and therapeutic approach. Steroids and antihistamines are very effective against mast-cell-mediated angioedema, but nearly useless against bradykinin-mediated angioedema. For angioedema induced by ACE inhibitors, no causally directed treatment has yet been approved.

Classification of ambiguous nerve fiber orientations in 3D polarized light imaging.

3D polarized light imaging (3D-PLI) has been shown to measure the orientation of nerve fibers in post mortem human brains at ultra high resolution. The 3D orientation in each voxel is obtained as a pair of angles, the direction angle and the inclination angle with unknown sign. The sign ambiguity is a major problem for the correct interpretation of fiber orientation. Measurements from a tiltable specimen stage, that are highly sensitive to noise, extract information, which allows drawing conclusions about the true inclination sign. In order to reduce noise, we propose a global classification of the inclination sign, which combines measurements with spatial coherence constraints. The problem is formulated as a second order Markov random field and solved efficiently with graph cuts. We evaluate our approach on synthetic and human brain data. The results of global optimization are compared to independent pixel classification with subsequent edge-preserving smoothing.

Automatic identification of gray and white matter components in polarized light imaging.

Polarized light imaging (PLI) enables the visualization of fiber tracts with high spatial resolution in microtome sections of postmortem brains. Vectors of the fiber orientation defined by inclination and direction angles can directly be derived from the optical signals employed by PLI analysis. The polarization state of light propagating through a rotating polarimeter is varied in such a way that the detected signal of each spatial unit describes a sinusoidal signal. Noise, light scatter and filter inhomogeneities, however, interfere with the original sinusoidal PLI signals, which in turn have direct impact on the accuracy of subsequent fiber tracking. Recently we showed that the primary sinusoidal signals can effectively be restored after noise and artifact rejection utilizing independent component analysis (ICA). In particular, regions with weak intensities are greatly enhanced after ICA based artifact rejection and signal restoration. Here, we propose a user independent way of identifying the components of interest after decomposition; i.e., components that are related to gray and white matter. Depending on the size of the postmortem brain and the section thickness, the number of independent component maps can easily be in the range of a few ten thousand components for one brain. Therefore, we developed an automatic and, more importantly, user independent way of extracting the signal of interest. The automatic identification of gray and white matter components is based on the evaluation of the statistical properties of the so-called feature vectors of each individual component map, which, in the ideal case, shows a sinusoidal waveform. Our method enables large-scale analysis (i.e., the analysis of thousands of whole brain sections) of nerve fiber orientations in the human brain using polarized light imaging.

High-resolution fiber tract reconstruction in the human brain by means of three-dimensional polarized light imaging.

Functional interactions between different brain regions require connecting fiber tracts, the structural basis of the human connectome. To assemble a comprehensive structural understanding of neural network elements from the microscopic to the macroscopic dimensions, a multimodal and multiscale approach has to be envisaged. However, the integration of results from complementary neuroimaging techniques poses a particular challenge. In this paper, we describe a steadily evolving neuroimaging technique referred to as three-dimensional polarized light imaging (3D-PLI). It is based on the birefringence of the myelin sheaths surrounding axons, and enables the high-resolution analysis of myelinated axons constituting the fiber tracts. 3D-PLI provides the mapping of spatial fiber architecture in the postmortem human brain at a sub-millimeter resolution, i.e., at the mesoscale. The fundamental data structure gained by 3D-PLI is a comprehensive 3D vector field description of fibers and fiber tract orientations - the basis for subsequent tractography. To demonstrate how 3D-PLI can contribute to unravel and assemble the human connectome, a multiscale approach with the same technology was pursued. Two complementary state-of-the-art polarimeters providing different sampling grids (pixel sizes of 100 and 1.6 µm) were used. To exemplarily highlight the potential of this approach, fiber orientation maps and 3D fiber models were reconstructed in selected regions of the brain (e.g., Corpus callosum, Internal capsule, Pons). The results demonstrate that 3D-PLI is an ideal tool to serve as an interface between the microscopic and macroscopic levels of organization of the human connectome.