The incidence and predictors of antibiotic-associated encephalopathy: a multicenter hospital-based study.

This study aimed to evaluate the incidence and likelihood of antibiotic-associated encephalopathy (AAE), comparing rates among the classes of antibiotics in monotherapy or in combination therapy. We also investigated the associations between the incidence of AAE and the glomerular filtration rate (GFR) and electroencephalogram features. Consecutive admissions that used any kind of antibiotics to treat infectious diseases were identified from six hospitals. We classified antibiotics according to three distinct pathophysiologic mechanisms and clinical subtypes. We searched for the incidence of AAE as the primary outcome. A total of 97,433 admission cases among 56,038 patients was identified. Cases that received type 1 antibiotics had significantly more frequent AAE compared to those that received type 2 antibiotics (adjusted odds ratio [OR], 2.62; 95% confidence interval [CI] 1.15-5.95; P = 0.021). Combined use of type 1 + 2 antibiotics was associated with a significantly higher incidence of AAE compared to the use of type 2 antibiotics alone (adjusted OR, 3.44; 95% CI 1.49-7.93; P = 0.004). Groups with GFR < 60 mL/min/1.73 m2 had significantly higher incidence rates of AAE compared to those with GFRs ≥ 90 mL/min/1.73 m2 among cases that received type 1 + 2 antibiotics. Detection of spike-and-wave or sharp-and-wave patterns on electroencephalogram was significantly more common in the combination therapy group. Combination use of antibiotics was associated with a higher incidence of AAE compared to monotherapy. The incidence of AAE significantly increased as renal function decreased, and epileptiform discharges were more likely to be detected in cases receiving combined antibiotics.

Clinical pitfalls and serological diagnostics of MuSK myasthenia gravis.

BACKGROUND: We aimed to evaluate the diagnostic accuracy of enzyme-linked immunosorbent assay (ELISA) for anti-muscle specific tyrosine kinase (MuSK) antibody (Ab) in a large cohort of anti-acetylcholine receptor (AChR) Ab-negative generalized myasthenia gravis (MG), and also to investigate clinical contexts for the diagnosis of MuSK MG. METHODS: A retrospective study of 160 patients with a clinical suspicion of AChR Ab-negative generalized MG was performed. The serum samples were tested for anti-clustered AChR Ab by cell-based assay (CBA), anti-MuSK Ab by ELISA, CBA and/or radioimmunoprecipitation assay (RIPA). Clinical data were compared between anti-MuSK Ab-positive MG and double seronegative (AChR and MuSK) MG groups. RESULTS: After excluding non-MG and clustered AChR Ab-positive patients, we identified 89 patients as a cohort of AChR Ab-negative generalized MG. Anti-MuSK Ab was positive by ELISA in 22 (24.7%) patients. While CBA identified five additional anti-MuSK Ab-positive patients, the results of ELISA were mostly consistent with CBA and RIPA with Cohen's kappa of 0.80 and 0.90, respectively (p < 0.001). The most frequent differential diagnosis was motor neuron disease particularly of bulbar onset which showed remarkably overlapping clinical and electrophysiological features with MuSK MG at presentation. CONCLUSION: While confirming the highest sensitivity of CBA for detecting anti-MuSK Ab, our results highlight the clinical pitfalls in making a diagnosis of MuSK MG and may support a diagnostic utility of MuSK-ELISA in clinical practice.

Smoking History and Clinical Features of Cluster Headache: Results from the Korean Cluster Headache Registry.

BACKGROUND AND PURPOSE: Epidemiologic data suggest that cluster headache (CH) is significantly associated with cigarette smoking. The aim of this study was to determine differences in features between patients with a smoking history and those who are never-smokers, using data from a prospective multicenter registry. METHODS: Data used in this study were obtained from the Korean Cluster Headache Registry that collected data from consecutive patients diagnosed with CH. We compared clinical and demographic features between ever-smokers (current or former smokers) and never-smokers. RESULTS: This study enrolled 250 patients who were diagnosed with CH, of which 152 (60.8%) were ever-smokers and 98 (39.2%) were never-smokers. The age at CH onset was significantly lower in the never-smoker group than in the ever-smoker group [27.1±12.9 years vs. 30.6±10.9 years (mean±standard deviation), p=0.024]. Seasonal rhythmicity (58.1% vs. 44.7%, p=0.038) and triptan responsiveness (100% vs. 85.1%, p=0.001) were higher in never-smokers, while other clinical features such as pain severity, duration, attack frequency, and associated autonomic symptoms did not differ significantly between the groups. The male-to-female ratio was markedly higher in ever-smokers (29.4:1) than in never-smokers (1.7:1). CONCLUSIONS: Most of the clinical features did not differ significantly between patients with a smoking history and never-smokers. However, the age at CH onset, sex ratio, and seasonal rhythmicity were significantly associated with smoking history.

Clinical features of chronic cluster headache based on the third edition of the International Classification of Headache Disorders: A prospective multicentre study.

The criterion for the remission period of chronic cluster headache (CCH) was recently revised from < 1 month to < 3 months in the third edition of the International Classification of Headache Disorders (ICHD-3). However, information on the clinical features of CCH based on the ICHD-3 criteria is currently limited. The present study aimed to investigate the clinical features of CCH based on ICHD-3 using data from the Korean Cluster Headache Registry (KCHR). The KCHR is a multicentre prospective registry of patients with cluster headache (CH) from 15 hospitals. Among the 250 participants with CH, 12 and 176 participants were classified as having CCH and episodic cluster headache (ECH), respectively. Among 12 participants with CCH, 6 (50%) had remission periods of < 1 month, and the remaining 6 (50%) had a remission period of 1-3 months. Six participants had CCH from the time of onset of CH, and in the other 6 participants, CCH evolved from ECH. CCH subjects had later age of onset of CH, developed the condition after a longer interval after CH onset, and had more migraine and less nasal congestion and/or rhinorrhoea than ECH subjects. Clinical features of CCH with remission periods < 1 month were not significantly different from those of CCH with remission periods of 1-3 months, except for the total number of bouts. More current smoking and less diurnal rhythmicity were observed in participants with CCH evolved from ECH compared to those with ECH. In conclusion, the number of subjects with CCH doubled when the revised ICHD-3 criteria were used. Most of clinical characteristics of CCH did not differ when the previous and current version of ICHD was applied and compared. Some clinical features of CCH were different from those of ECH, and smoking may have a role in CH chronification.