Neuroimaging findings in headache with normal neurologic examination: Systematic review and meta-analysis.

OBJECTIVE: To determine if pooled estimates of the prevalence of unexpected findings in patients with headache and normal neurologic examination support current expert opinion-based neuroimaging guidelines. METHODS: We searched PubMed and EMBASE for studies reporting neuroimaging findings in patients with headache and normal neurologic examination up to September 30, 2017. The overall and disease-specific prevalence of unexpected findings were pooled through random-effects meta-analysis. This study is registered with PROSPERO, registration number CRD42017079714. RESULTS: In forty-one studies including 15,760 participants, the overall prevalence of unexpected findings and normal variants was 17.5% (95% CI: 13.1-22.3). The prevalence was 26.6% (95% CI: 15.5-39.4) in studies using MRI only. The prevalence of vascular, neoplastic, and non-neoplastic findings was 6.6%, 1.4%, and 9.6%. The pooled disease-specific prevalence was 2.0% for stroke, 1.8% for aneurysms, 0.8% for subdural hematoma, 0.7% for hydrocephalus, 0.2% for glioma, and 0.1% for meningioma. In secondary analysis, there was 0.4% increase in the prevalence of vascular unexpected findings with each 1% increase in the proportion of migraine with aura (p-value for meta-regression = 0.005). CONCLUSIONS: In patients with headache and normal neurologic examination, important vascular and neoplastic unexpected findings are rare and better detected with MRI. This supports current American College of Radiology and European Headache Federation recommendations to avoid systematic imaging in such patients and prefer MRI when imaging is needed.

Rate of Recurrence of Adverse Events Following Immunization: Results of 19 Years of Surveillance In Quebec, Canada.

BACKGROUND: While adverse events following immunization (AEFI) are frequent, there are limited data on the safety of reimmunizing patients who had a prior AEFI. Our objective was to estimate the rate and severity of AEFI recurrences. METHODS: We analyzed data from the AEFI passive surveillance system in Quebec, Canada, that collects information on reimmunization of patients who had a prior AEFI. Patients with an initial AEFI reported to the surveillance system between 1998 and 2016 were included. Rate of AEFI recurrence was calculated as number of patients with recurrence/total number of patients reimmunized. RESULTS: Overall, 1350 patients were reimmunized, of which 59% were 2 years of age or younger. The AEFI recurred in 16% (215/1350) of patients, of whom 18% (42/215) rated the recurrence as more severe than the initial AEFI. Large local reactions extending beyond the nearest joint and lasting 4 days or more had the highest recurrence rate (67%, 6/9). Patients with hypotonic hyporesponsive episodes had the lowest rate of recurrence (2%, 1/50). Allergic-like events recurred in 12% (76/659) of patients, but none developed anaphylaxis. Of 33 patients with seizures following measles mumps rubella with/without varicella vaccine, none had a recurrence. Compared with patients with nonserious AEFIs, those with serious AEFIs were less often reimmunized (60% versus 80%; rate ratio: 0.8; 95% confidence interval: 0.66-0.86). CONCLUSIONS: Most patients with a history of mild or moderate AEFI can be safely reimmunized. Additional studies are needed in patients with serious AEFIs who are less likely to be reimmunized.

Investigation of an increase in large local reactions following vaccine schedule change to include DTaP-HB-IPV-Hib (Infanrix-hexa®) and MMRV (ProQuad®) at 18 months of age.

CONTEXT: In 2015 in Quebec, Canada, the passive vaccine adverse event reporting system detected an increase in large local reactions associated with vaccines recommended at the 18-month visit. This followed changes to the pediatric vaccine schedule to include hexavalent diphtheria-tetanus-acellular-pertusis-inactivated polio-Haemophilus influenzae type b-hepatitis B vaccine (DTaP-IPV-Hib-HB, Infanrix-hexa®, GSK) and quadrivalent measles-mumps-rubella-varicella vaccine (MMRV, ProQuad®, Merck) as 18-month booster doses. OBJECTIVES: To determine if the excess of large local reactions was caused by a specific vaccine or their co-administration in the same limb or during the same visit. METHODS: A case-control study was conducted among cases born between January 2012 and April 2015 with a large local reaction following MMR ±â€¯V or DTaP-IPV-Hib ±â€¯HB vaccines administered between 16 and 23 months of age. Controls were randomly selected from the provincial medicare database among children born during the same period. RESULTS: Our analysis included 96 cases and 494 controls vaccinated with MMRV or DTaP-IPV-Hib ±â€¯HB vaccines. Among the 96 cases, 46% had a cellulitis and 54% had an injection site reaction extending beyond the nearest joint and/or lasting ≥ 4 days. Among the 39 cases who were immunized in different limbs, 77% of the large local reactions were located at the Infanrix-hexa® site, 5% at the DTaP-IPV-Hib site and 18% at the ProQuad® site. Large local reactions were significantly more frequent with Infanrix-hexa® than with DTaP-IPV-Hib vaccine (OR 5.9 95% CI: 1.4-25.7). Administration of ProQuad® and Infanrix-hexa® in the same limb did not increase the risk of large local reactions. CONCLUSION: This investigation suggested that most large local reactions were causally associated with the Infanrix-hexa® vaccine and that the risk was not greater when ProQuad® and Infanrix-hexa® were administered in the same limb. Given the improved vaccine coverage for hepatitis B, benefit-risk analysis likely still favours ongoing use of Infanrix-hexa® with informed parental consent.

Neuroimaging of headaches in patients with normal neurological examination: protocol for a systematic review.

INTRODUCTION: Headache disorders (HD) are among the most frequent neurological disorders seen in neurology practice. Because secondary HD are rare, patients' examination is most often unremarkable. However, the will to relieve patients' anxiety and the fear of prosecutions lead to overuse of neuroimaging thus resulting in the discovery of incidental findings (IF) or normal variants that can lead to futile or harmful procedures. Knowing the probability of identifying a potentially clinically significant lesion in patients with isolated headache could facilitate decision-making and reduce health costs. This review aims to determine the prevalence of incidental findings and normal anatomic variants (NAV) on neuroimaging studies performed in patients presenting with headache and normal neurological examination. METHOD AND ANALYSIS: Studies reporting neuroimaging findings in patients with headache and normal neurological examination and published before the 30 September 2017 will be identified by searching PubMed, Medline and EMBASE (Excerpta Medica Database). Relevant unpublished papers and conference proceedings will also be checked. Full texts of eligible studies will then be accessed and data extracted using a standard data extraction sheet. Studies will be assessed for quality and risk of bias. Heterogeneity of studies will be evaluated by the χ2 test on Cochrane's Q statistic. The prevalence of NAV and IF across studies and in relevant subgroups will be estimated by pooling the study-specific estimates using a random-effects meta-analysis. Visual analysis of funnel plot and Egger's test will be used to detect publication bias. The report of this systematic review will be compliant with the Meta-analysis of Observational Studies in Epidemiology guidelines. ETHICS AND DISSEMINATION: The current study is based on published data; ethical approval is, therefore, not required. The final report of this systematic review will be published in a peer-reviewed journal. Furthermore, findings will be presented at conferences and submitted to relevant health authorities. TRIAL REGISTRATION NUMBER: CRD42017079714.

Clinical Approach Used in Medical Consultations for Allergic-Like Events Following Immunization: Case Series Report in Relation to Practice Guidelines.

BACKGROUND: The Joint Task Force on Practice Parameters (JTFPP) guidelines for the investigation and reimmunization of patients who experienced allergic-like events (ALEs) after immunization are predicated on the likelihood of anaphylaxis, assessed through the time to symptom onset (≤ or >4 hours) and number of systems involved. OBJECTIVE: The objectives of this study were to compare the management of a series of patients with ALE in actual practice relative to JTFPP guidelines and to discuss key concepts and considerations in their use. METHODS: This retrospective study was based on a chart review of patients who consulted for suspected vaccine-associated ALEs at a large allergy department in Canada. RESULTS: Only 3 of the 135 patients who presented ALEs after immunization were referred for suspected anaphylaxis. There was no significant difference in the frequency of skin testing or reimmunization of patients whatever the time to symptom onset or number of systems involved in the ALE. Eight patients whose initial ALE occurred within 1 hour after immunization had a recurrence on reimmunization. Another patient whose initial ALE occurred 10 hours after influenza immunization had throat tightening and difficulty swallowing without objective signs. CONCLUSIONS: Most ALEs after immunization are not suggestive of anaphylaxis and should not be managed as such. The definition of anaphylaxis in the JTFPP guidelines is nonspecific and may need to be revisited. Restricting skin testing and graded dose reimmunization to patients whose ALE onset is ≤1 hour (compatible with IgE-mediated reaction) and to those meeting specific clinical criteria for anaphylaxis (whatever the timing) is likely a sufficiently sensitive and cautious approach.