Serious infections in patients with myasthenia gravis: population-based cohort study.

BACKGROUND AND PURPOSE: To characterize the frequency and risk of serious infections in patients with myasthenia gravis (MG) relative to age/sex/area-matched comparators. METHODS: This was a population-based cohort study in Ontario, Canada of patients with newly-diagnosed MG and 1:4 age/sex/area-matched general population comparators accrued from 1 April 2002 to 31 December 2015. The main outcome was a serious infection, defined by a primary diagnosis code on a hospitalization or emergency department record. We computed crude overall and sex-specific rates of infection among patients with MG and comparators, and the frequency of specific types of infection. Adjusted hazard ratios and 95% confidence intervals were estimated using Cox regression. RESULTS: Among 3823 patients with MG, 1275 (33.4%) experienced a serious infection compared with 2973/15 292 (19.4%) of comparators over a mean follow-up of over 5 years. Crude infection rates among patients with MG were twice those in comparators (72.5 vs. 35.0 per 1000 person-years, respectively). The most common infection types were respiratory infections, particularly bacterial pneumonia. After adjustment for potential confounders, MG was associated with a 39% increased infection risk (adjusted hazard ratio, 1.39; 95% confidence intervals, 1.28-1.51). CONCLUSIONS: Patients with MG are at a significantly higher absolute and relative risk of serious infections compared with age/sex/area-matched comparators. This needs to be considered when selecting MG treatments and when planning vaccination/prophylaxis. Determining whether this risk is due to the use of immunosuppressive medications (vs. MG itself) is an important area for future research.

The impact of CT head scans on ED management and length of stay in bizarre behavior patients.

METHODS: A 5-year retrospective chart review was conducted at 3 EDs. Inclusion criteria were patients ≥18years old triaged as "mental health - bizarre behavior" (deviation from normal cognitive behaviour with no obvious cause) with a CT head scan ordered in the ED. Exclusion criteria were focal neurologic deficits on exam, alternative medical etiology (i.e. delirium, trauma) and/or pre-existing CNS disease. Clinical, demographic and administrative data were extracted with 10% of charts independently reviewed by an Emergency Physician for inter-rater reliability. RESULTS: 266 cases met study criteria. Population demographics: 49% percent female, average age 51years old, 28% homeless, 58% arrived by police or ambulance. CT head results: 1 (0.4%) case with possible acute findings, 105 (39%) with incidental findings (i.e. cerebral atrophy) that did not impact clinical management. Average time to physician assessment was 1:48 (hour:min) (sd 1:11), time to CT completion was 5:05 (sd 7:28) and an average delay of 3:17 awaiting results. Subgroup analysis revealed a net increase in ED length of stay (ED LOS) of 5:02 from obtaining neuroimaging. 85% of patients were referred to a consultant, 92% were to psychiatry. CONCLUSIONS: CT head results prolonged ED LOS, delayed patient disposition and did not change the patient's clinical management. A prospective trial for ordering CT head scans in these patients is warranted.

Does prediabetes cause small fiber sensory polyneuropathy? Does it matter?

BACKGROUND AND OBJECTIVES: The association between prediabetes and distal polyneuropathy (DPN) remains controversial. Here we test whether the prevalence of small fiber sensory distal polyneuropathy is increased in prediabetes. METHODS: Prospectively recruited cohorts of healthy subjects and those with prediabetes from Olmsted County, Minnesota, were assessed for positive neuropathic sensory symptoms, or pain symptoms characteristic of small fiber sensory DPN. Hyperalgesia and hypoalgesia were assessed by "smart" quantitative sensation testing (QST). The prevalence of symptoms and QST abnormalities were compared among the groups. RESULTS: There was no significant increase in the prevalence of positive neuropathic sensory or pain symptoms, nor of hyper- or hypoalgesia in the prediabetes group. There was an increased prevalence of hypoalgesia of the foot only in newly diagnosed diabetes. CONCLUSIONS: Based on positive sensory and pain symptoms and QSTs, we did not find an increase in small fiber sensory DPN in prediabetes. Recognizing that obesity and diabetes mellitus are implicated in macro- and microvessel complications, physicians should encourage healthy living and weight loss in patients with prediabetes. In medical practice, alternate causes should be excluded before concluding that small fiber sensory distal neuropathy is secondary to prediabetes.

Excessive Daytime Sleepiness in Patients with Myasthenia Gravis.

Excessive daytime sleepiness (EDS) has not been investigated using objective tests in myasthenia gravis (MG). We investigated whether objective measurements of somnolence better detected abnormalities compared with sleepiness questionnaires in MG, and determine if MG patients have EDS. Eight patients with mild-to-moderate MG were recruited. Patients completed maintenance of wakefulness, overnight polysomnography, multiple sleep latency tests, Epworth Sleepiness Scale, and fatigue questionnaires. Seven patients demonstrated EDS on objective testing, while Epworth scores were abnormal in two, and the measures showed poor correlation. Our findings highlight that the ESS may be inadequate to diagnose EDS and lead to under-reporting of daytime somnolence in patients with MG.