[Results of vagus nerve stimulator implantation in children and adolescents with treatment-refractory epilepsy]. / Ergebnisse der Vagusnervstimulatorimplantation bei Kindern und Jugendlichen mit therapierefraktärer Epilepsie.

Vagus nerve stimulation (VNS) is a therapeutic procedure that can be applied in a palliative setting in patients with treatment-refractory epilepsy who are not suitable for epilepsy surgery. The mechanism of action of VNS is currently not completely understood but appears to depend on a modification of neurotransmitter metabolism. Data of 25 patients with treatment-refractory epilepsy who underwent implantation of a vagus nerve stimulator were retrospectively analyzed in a monocentric study. A reduction in epileptic seizure rate of 28% was observed 3 months after initial activation and of 32.9% after 6-12 months. The responder rate (reduction in seizure rate of more than 50% compared to before implantation) was 40% 6-12 months after initial activation. In one third of patients, a reduction in epileptic seizure rate of at least 75% occurred. Adverse effects of surgery or the stimulation were rare.

[Granulomatosis with polyangiitis - manifestations in the head and neck area]. / Granulomatose mit Polyangiitis ­ Manifestationen im Kopf-Hals-Bereich.

Granulomatosis with polyangiitis is a rare chronic rheumatologic systemic disease with a vasculitis of small- and medium-size vessels. Mostly the upper airways, lung and kidneys are affected. Symptoms are unspecific. Patients complain about stuffy nose, crustiness of nasal secretions, ulcera of the oral mucosa or epistaxis. The otorhinolaryngologist may be the first one to evaluate the patient's health condition. Long term complications may be cardial, renal or pulmonal failure. To this day the aetiology is still unknown. Severe disease is treated with a combination of immunosuppressive medications. Clinic examinations and laboratory tests should be carried out for life-time.

Human CLC-K Channels Require Palmitoylation of Their Accessory Subunit Barttin to Be Functional.

CLC-K/barttin chloride channels are essential for NaCl re-absorption in Henle's loop and for potassium secretion by the stria vascularis in the inner ear. Here, we studied the posttranslational modification of such channels by palmitoylation of their accessory subunit barttin. We found that barttin is palmitoylated in vivo and in vitro and identified two conserved cysteine residues at positions 54 and 56 as palmitoylation sites. Point mutations at these two residues reduce the macroscopic current amplitudes in cells expressing CLC-K/barttin channels proportionally to the relative reduction in palmitoylated barttin. CLC-K/barttin expression, plasma membrane insertion, and single channel properties remain unaffected, indicating that these mutations decrease the number of active channels. R8W and G47R, two naturally occurring barttin mutations identified in patients with Bartter syndrome type IV, reduce barttin palmitoylation and CLC-K/barttin channel activity. Palmitoylation of the accessory subunit barttin might thus play a role in chloride channel dysfunction in certain variants of Bartter syndrome. We did not observe pronounced alteration of barttin palmitoylation upon increased salt and water intake or water deprivation, indicating that this posttranslational modification does not contribute to long term adaptation to variable water intake. Our results identify barttin palmitoylation as a novel posttranslational modification of CLC-K/barttin chloride channels.

Rare Differential Diagnosis of Dyspnea: Extramedullary Plasmocytoma (EMP) of the Larynx-Case Report and Review of the Latest Literature of Laryngeal EMP and Laryngeal Involvement of Multiple Myeloma.

Multiple myeloma (MM) of the larynx is extremely rare. It can be either a laryngeal manifestation of a general multiple myeloma or it can occur as a primary laryngeal mass, which is then called extramedullary plasmocytoma (EMP). We present the case of an 81-year-old male patient who was admitted for dyspnea. He had a history of multiple myeloma but was in complete remission since some years. Histological and immunohistological examination of tissue samples revealed an EMP. The patient was first treated by laser surgery in order to reduce the tumor mass and secure the airway. Afterwards, he was systematically treated by radiation therapy with 60 Gy, which achieved a good response and complete remission proven by control laryngoscopy and histological examination of tissue samples taken from the former tumor area three months after laser excision. The latest literature in the field is reviewed. There were only ten cases of EMP in the larynx or laryngeal involvement of MM published within the last five years (Pubmed was searched for "larynx," "laryngeal" and "EMP," "Extramedullary Myeloma," "Multiple Myeloma," and "MM"). Due to its rarity, there are currently no evidence-based therapeutic guidelines available. For their development, multicenter studies are required.