Effectiveness and safety profile of greater occipital nerve blockade in cluster headache: a systematic review.

BACKGROUND: Greater occipital nerve (GON) blockade is a short-term preventive therapy for cluster headache (CH). We conducted a systematic review to evaluate the effectiveness and safety of GON blockade in patients with CH. METHODS: On 23 October 2020, we searched MEDLINE, Embase, Embase Classic, PsycINFO, CINAHL, CENTRAL and Web of Science databases from their inception date. Studies included participants with a CH diagnosis who received corticosteroid and local anaesthetic suboccipital region injections. Outcomes were change in the frequency/severity/duration of attacks; proportion of participants responding to treatment, time to attack freedom from an attack, change in attack bout length and/or the presence of adverse effects after GON blockade. Risk of bias was assessed with the Cochrane Risk of Bias V.2.0 (RoB2)/Risk of Bias in Non-randomized Studies - of Interventions (ROBINS- I) tools and a specific tool for case reports/series. RESULTS: Two RCTs, eight prospective and eight retrospective studies, and four case reports were included in the narrative synthesis. Every effectiveness study found a significant response in one or more of frequency/severity/duration of individual attacks or proportion of patients responding to treatment (47.8%-100.0%). There were five instances of potentially irreversible adverse effects. A higher injectate volume and use of concurrent prophylaxis may be associated with an increased likelihood of response. Methylprednisolone may have the best safety profile of available corticosteroids. DISCUSSION: GON blockade is safe and effective for CH prevention. Higher injectate volumes may improve likelihood of response, and the likelihood of serious adverse events may be reduced by using methylprednisolone. PROSPERO REGISTRATION NUMBER: CRD42020208435.

Endocrine dysregulation in aneurysmal subarachnoid haemorrhage.

INTRODUCTION: Aneurysmal Subarachnoid haemorrhage (aSAH) is one of the most common causes of neurocritical care admission. Consistent evidence has been suggestive of endocrine dysregulation in aSAH. This review aims to provide an up-to-date presentation of the available evidence regarding endocrine dysregulation in aneurysmal subarachnoid haemorrhage. METHODS: A comprehensive literature search was performed using PubMed database. All available evidence related to endocrine dysregulation in hypothalamic-pituitary hormones, adrenal hormones and natriuretic peptides after aSAH, published since 2010, were reviewed. RESULTS: There have been reports of varying prevalence of dysregulation in hypothalamic-pituitary and adrenal hormones in aSAH. The cause of this dysregulation and its pattern remain unclear. Hypothalamic-pituitary and adrenal dysregulation have been associated with higher incidence of poor neurological outcome and increased mortality. Whilst there is evidence that long-term dysregulation of these axes may also develop, it appears to be less frequent than the acute-phase dysregulation and transient in pattern. Increased levels of catecholamines have been reported in the hyper-acute phase of aSAH with reported inconsistent correlation with the outcomes and the complications of the disease. There is growing evidence that of a causal link between the endocrine dysregulation and the development of hyponatraemia and delayed cerebral ischaemia, in the acute phase of aSAH. However, the pathophysiological mechanism and pattern of endocrine dysregulation which could be causally associated with these complications still remain debatable. CONCLUSION: The evidence, mainly from small observational and heterogeneous in methodology studies, is suggestive of adverse effects of the endocrine dysregulation on the outcome and the incidence of complications of the disease. However, the cause of this dysregulation and a pathophysiological mechanism that could link its presence with the development of acute complications and the outcome of the aSAH remain unclear. Further research is warranted to elucidate the clinical significance of endocrine dysregulation in subarachnoid haemorrhage.

Particles in Exhaled Air (PExA): Clinical Uses and Future Implications.

Access to distal airway samples to assess respiratory diseases is not straightforward and requires invasive procedures such as bronchoscopy and bronchoalveolar lavage. The particles in exhaled air (PExA) device provides a non-invasive means of assessing small airways; it captures distal airway particles (PEx) sized around 0.5-7 µm and contains particles of respiratory tract lining fluid (RTLF) that originate during airway closure and opening. The PExA device can count particles and measure particle mass according to their size. The PEx particles can be analysed for metabolites on various analytical platforms to quantitatively measure targeted and untargeted lung specific markers of inflammation. As such, the measurement of distal airway components may help to evaluate acute and chronic inflammatory conditions such as asthma, chronic obstructive pulmonary disease, acute respiratory distress syndrome, and more recently, acute viral infections such as COVID-19. PExA may provide an alternative to traditional methods of airway sampling, such as induced sputum, tracheal aspirate, or bronchoalveolar lavage. The measurement of specific biomarkers of airway inflammation obtained directly from the RTLF by PExA enables a more accurate and comprehensive understanding of pathophysiological changes at the molecular level in patients with acute and chronic lung diseases.

Multiple Organ Dysfunction Secondary to Herpes Simplex Virus -1 Reactivation After Treatment With Dexamethasone and Sarilumab for Covid-19 Disease.

Introduction: The immunological response to the SARS-CoV-2 virus and the treatment of COVID-19 disease present a potential susceptibility to viral reactivation, particularly Herpes simplex virus-1 (HSV-1). Case Presentation: A 49-year-old female presented to hospital with severe COVID-19 pneumonitis and was given sarilumab and dexamethasone. She was intubated and ventilated in the intensive care unit (ICU) and initially demonstrated biochemical and clinical evidence of improvement. This was followed by a severe acute deterioration in respiratory, renal, and cardiovascular function, accompanied by a vesicular rash on the face. Polymerase chain reaction confirmed HSV-1 reactivation and treatment with acyclovir was commenced. After 49 days in ICU the patient was successfully weaned from all organ support, and she made a satisfactory recovery. Conclusions: HSV-1 reactivation is common in COVID-19 and likely contributes to poorer clinical outcomes. The mechanism causing susceptibility to viral reactivation is not clearly defined, however, the development of critical illness induced immunosuppression via dysfunction of interferon and interleukin pathways is a likely mechanism. This effect could be perpetuated with immunosuppressant medications, although further research is needed to characterise this phenomenon.

Retrospective cause analysis of troponin I elevation in non-CAD patients: Special emphasis on sepsis.

BACKGROUND: Troponin I is one of the most commonly tested biochemical markers in the emergency room (ER) and in the hospital setting. Besides coronary artery disease (CAD), demand ischemia with underlying tachycardia, anemia, hypertensive emergency, congestive heart failure, kidney disease, sepsis, and pulmonary embolism have also been reported to cause troponin I elevations. Few reports have excluded patients with CAD, and no study has summarized the proportion of these factors relative to an increased troponin I level. METHODS: The aim of this retrospective study was to investigate the level of contribution of causative factors in troponin I elevation. Charts of patients tested for troponin I during an ER visit or during hospitalization were collected. Patients with known CAD, abnormal stress tests, cardiac catheterizations, or discharge without an adequate cardiac evaluation were excluded. Logistic regression was used to identify predictors of elevated troponin I levels. RESULTS: A total of 586 patients were investigated in this study. Age, hemoglobin (Hb), heart rate (HR), glomerularfiltration rate, atrial fibrillation, congestive heart failure (CHF), and sepsis were significant predictors of elevated troponin I by analysis in univariate logistic regression (all P < .001). In multivariate logistic regression, sepsis, CHF, age, Hb, and HR were independent predictors of troponin I (all P < .01). A simple clinical scoring system was generated with 1 score on patients with age ≥ 60, Hb < 10 g/dL, and HR ≥ 100 beats per minute (bpm). The prevalence of elevated troponin I was 4%, 16%, 38%, and 50% for patients with scores of 0, 1, 2, and 3, respectively. In patients without sepsis and CHF, the chances of elevated troponin I were 2%, 11%, 28%, and 43%. CONCLUSIONS: Sepsis was found to be the strongest independent cause of elevated troponin I levels in non-CAD patients. The scoring system composed of age, hemoglobin (Hb), and heart rate (HR) can assist clinical evaluation of elevated troponin I test in non-CAD patients.

Laparoscopic cholecystectomy in a patient with erythropoietic protoporphyria.

Erythropoietic protoporphyria (EPP) is an inherited defect in haem synthesis causing dangerous phototoxic reactions following exposure to wavelengths of light around 400nm. It can cause catastrophic post-operative complications following open surgery, in which environment various safety measures are now routinely employed. The dangers at laparoscopy have never been discussed in the literature, and nor have any specific precautions been recommended. We describe a 35 year old woman with gallstones undergoing prophylactic laparoscopic cholecystectomy to prevent future cholestasis precipitating porphyric liver failure. A pre-operative trial of the cutaneous effects of the laparoscopic light source was performed to assess the potential risk of use within the peritoneal cavity. The procedure was uneventful and the patient suffered no adverse reaction. We suggest that a trial of the effects of the laparoscopic light source on the skin of EPP patients provides valid reassurance regarding the safety of the laparoscopy for short surgical procedures.

Family medicine patients' use of the Internet for health information: a MetroNet study.

We explored a diverse sample of family medicine patients' use of the internet for health information. Primary objectives were to determine the extent of access to the Internet, and among those with access, the types of health information sought; how they search for that information; and how they assess the accuracy of the information. We also surveyed the physicians' perceptions of their patients' use of the Internet for health information. Of 1289 patients participating, 65% reported access to the internet; age, sex, race, education, and income were each significantly associated with internet access. A total of 74% of those with access had used the Internet to find health information for themselves or family members. Disease-specific information was most frequently sought, followed by medication information, and then information about nutrition and exercise. Patients determine website accuracy by the endorsement of the site by a government agency or a professional organization, their own perception of reliability of the website source, and the understandability of the information. Almost 90% attempted to verify the information they obtained. A majority had discussed website information with their physicians. The physicians (n = 92) underestimate the proportion of their patients who used the Internet for health information. A total of 36% of physicians said at least one patient per week brought in Internet health information, and 63% said they had suggested a specific website to their patients. Physicians need critical appraisal skills to determine whether information found by a patient is relevant to that patient's condition and is based on the best available evidence. In addition, physicians directing patients to websites for health information must be confident that the site is maintained and updated by a reliable and credible source.

Measurement practices: methods for developing content-valid student examinations.

Measurement experts generally agree that a systematic approach to test construction will probably result in an instrument with sound psychometric properties. One fundamental method is called the blueprint approach to test construction. A test blueprint is a tool used in the process for generating content-valid exams by linking the subject matter delivered during instruction and the items appearing on the test. Unfortunately, this procedure as well as other educational measurement practices is often overlooked A survey of curriculum administrators at 144 United States and international medical schools was conducted to assess the importance and prevalence of test blueprinting in their school. Although most found test blueprinting to be very important, few require the practice. The purpose of this paper is to review the fundamental principals associated with achieving a high level of content validity when developing tests for students. The short-term efforts necessary to develop and integrate measurement theory into practice will lead to long-term gains for students, faculty and academic institutions.

Impaired glucose homeostasis, neutrophil trafficking and function in mice lacking the glucose-6-phosphate transporter.

Glycogen storage disease type Ib (GSD-Ib) is caused by a deficiency in the glucose-6-phosphate transporter (G6PT). In addition to disrupted glucose homeostasis, GSD-Ib patients have unexplained and unexpected defects in neutrophil respiratory burst, chemotaxis and calcium flux, in response to the bacterial peptide f-Met-Leu-Phe, as well as intermittent neutropenia. We generated a G6PT knockout (G6PT-/-) mouse that mimics all known defects of the human disorder and used the model to further our understanding of the pathogenesis of GSD-Ib. We demonstrate that the neutropenia is caused directly by the loss of G6PT activity; that chemotaxis and calcium flux, induced by the chemokines KC and macrophage inflammatory protein-2, are defective in G6PT-/- neutrophils; and that local production of these chemokines and the resultant neutrophil trafficking in vivo are depressed in G6PT-/- ascites during an inflammatory response. The bone and spleen of G6PT-/- mice are developmentally delayed and accompanied by marked hypocellularity of the bone marrow, elevation of myeloid progenitor cell frequencies in both organs and a corresponding dramatic increase in granulocyte colony stimulating factor levels in both GSD-Ib mice and humans. So, in addition to transient neutropenia, a sustained defect in neutrophil trafficking due to both the resistance of neutrophils to chemotactic factors, and reduced local production of neutrophil-specific chemokines at sites of inflammation, may underlie the myeloid deficiency in GSD-Ib. These findings demonstrate that G6PT is not just a G6P transport protein but also an important immunomodulatory protein whose activities need to be addressed in treating the myeloid complications in GSD-Ib patients.