6 Ratge et al. had similar findings but showed an initial prompt restoration (within hours to a few days) and then a one- to two-month improvement in the beta-2 adrenergic system on lymphocytes.7 Other work has shown down-regulation of adrenoreceptors in phaeochromacytoma as a consequence of catecholamines in rat renal cortices8 and 9 and rat
hearts.10, 11 and 12 In phaeochromocytoma there are often extremely high levels of catecholamines. However, endogenous down-regulation has been seen in humans at more normal physiological levels. Beta-2 adrenergic receptor down-regulation has been documented in the muscle biopsy of healthy individuals who are overtrained (they had a non-significant ALK inhibitor increase in nocturnal urinary epinephrine).13 Alpha-2 and beta-2 adrenoreceptor down-regulation has been demonstrated on platelets and lymphocytes of marathon runners in the presence of increased catecholamine levels.14 Catecholamine and beta-adrenergic receptor levels have not been studied in patients with ALS before and after initiation of NIV. Sudden circulatory collapse has been reported in invasively ventilated patients with amyotrophic lateral sclerosis,15 which may have been related to autonomic dysfunction. In these patients
the blood pressure response to noradrenaline infusion was poor, consistent with down-regulation of adrenoreceptors induced by the constant sympathetic hyperactivity. Shimizu et al. have shown down-regulation of alpha adrenoreceptors in the peripheral blood vessels of ventilated ALS patients, buy MS-275 whilst examining blood pressure dysfunction. Of note, these cases differ from our own observation as our patient only
suffered episodes of profound bradycardia when NIV was interrupted. Whilst this appears to be a relatively uncommon phenomenon, it settled with conservative management. Awareness of this occurrence and its natural history may avoid unnecessary pacemaker insertion and is relevant to respiratory Selleckchem Verteporfin physicians, cardiologists, neurologists and intensivists alike. No authors have any actual or potential conflict of interest including any financial, personal or other relationships that can influence or bias this case report. “
“Generalised Lymphatic Dysplasia is a rare condition affecting 1.15/100,000 people aged <20 years.1 Historically patients have been divided according to age of onset, however an improved classification based on phenotype has recently been published.2 Clinical presentation is variable and may include systemic involvement such as pleural effusions.2 and 3 In this context pleural effusions are recognised to be difficult to manage and are often refractory to conventional treatment approaches.4 A 15-year-old girl was referred to tertiary paediatric respiratory services following identification of bilateral pleural effusions during investigation of delayed puberty.