Causal association between blood metabolites and vertigo: A Mendelian randomization study.

Metabolic disorders have been identified as an important factor causing nervous system diseases. However, due to the interference of confounding factors, the causal relationship between them has not been clearly elucidated, so it is necessary to study the causal relationship between them. To explore the causal relationship between blood metabolites and vertigo by Mendelian randomization. To assess causality, the inverse variance weighting method was employed as the primary analytical approach, complemented by additional sensitivity analyses. Metabolic pathway enrichment analysis and genetic correlation analysis were employed to further assess the metabolites. All statistical analyses were conducted using the R software. The study employed metabolite Genome Wide Association Study and vertigo diseases summary data sets to examine the causal relationship between 486 blood metabolites and 3 types of vertigo. A total of 55 potential metabolites associated with the 3 types of vertigo were identified, with 22, 16, and 13 candidate metabolites showing relatively reliable MR Evidence for Vestibular Dysfunction, Peripheral Vertigo, and Central Vertigo, respectively. Enrichment analysis was conducted to investigate the biological significance of these candidate metabolites, resulting in the identification of 7 key metabolic pathways across the 3 diseases, the metabolic pathway known as "Valine, leucine, and isoleucine biosynthesis" was found to be associated with all 3 types of vertigo, suggesting its potential influence on the vestibular system. Genetic correlation analysis revealed a genetic correlation between X-10510 and dodecanedioate with Vestibular Dysfunction. This study offers novel perspectives on the causal impact of blood metabolites on vertigo through the integration of genomics and metabolomics. Identifying metabolites that contribute to vertigo could serve as potential biomarkers and contribute to a better understanding of the underlying biological mechanisms associated with vertigo.

Serum miRNA125a-5p, miR-125b-5p, and miR-433-5p as biomarkers to differentiate between posterior circulation stroke and peripheral vertigo.

BACKGROUND: Acute vertigo is a common presentation of inner ear disease. However, it can also be caused by more serious conditions, especially posterior circulation stroke. Differentiating between these two conditions by clinical presentations and imaging studies during the acute phase can be challenging. This study aimed to identify serum microRNA (miRNA) candidates that could differentiate between posterior circulation stroke and peripheral vertigo, among patients presenting with acute vertigo. METHODS: Serum levels of six miRNAs including miR-125a-5p, miR-125b-5p, miR-143-3p, miR-342-3p, miR-376a-3p, and miR-433-5p were evaluated. Using quantitative reverse-transcription polymerase chain reaction (RT-qPCR), the serum miRNAs were assessed in the acute phase and at a 90 day follow-up visit. RESULTS: A total of 58 patients with posterior circulation stroke (n = 23) and peripheral vertigo (n = 35) were included in the study. Serum miR-125a-5p (P = 0.001), miR-125b-5p (P <  0.001), miR-143-3p (P = 0.014) and miR-433-5p (P = 0.0056) were present at significantly higher levels in the acute phase, in the patients with posterior circulation infarction. Based on the area under the receiver operating characteristic curve (AUROC) only miR-125a-5p (0.75), miR-125b-5p(0.77), and miR-433-5p (0.71) had an acceptable discriminative ability to differentiate between the central and peripheral vertigo. A combination of miRNAs revealed no significant improvement of AUROC when compared to single miRNAs. CONCLUSION: This study demonstrated the potential of serum miR-125a-5p, miR-125b-5p, and miR-433-5p as biomarkers to assist in the diagnosis of posterior circulation infarction among patients presenting with acute vertigo.

[Preliminary analysis of central paroxysmal positional vertigo].

Objective: To explore the possible pathogenesis of central paroxysmal positional vertigo (CPPV) by analyzing its clinical manifestations and characteristics. Methods: The clinical data of 3 patients with CPPV, including 1 male and 2 females, aged 36, 14 and 70 years old respectively, were collected from the Department of Otorhinolaryngology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences from June 2014 to June 2018. The clinical symptoms, nystagmus, other central ocular motor abnormalities, MRI, PET-CT, and laboratory findings were analyzed retrospectively. Results: All patients showed transient vertigo and nystagmus induced by head changes relative to gravity, but the characteristics of nystagmus did not conform to the typical characteristics of nystagmus in benign paroxysmal positional vertigo. None of patients response to repositioning maneuvers, and all patients presented with the signs of abnormal visual oculomotor system or other symptoms of central system. MRI, PET-CT and blood biochemical tests confirmed that the causes of CPPV in the patients were chronic hemorrhage, inflammation and paraneoplastic cerebellar degeneration. Although the etiology of the three cases is different, the lesion site is involved in the central velocity storage mechanism. Conclusion: The damage of central velocity storage mechanism may lead to the damage of feedback rotation signal correction pathway, and CPPV appears when the head position changes relative to gravity.

Effects of Peripheral Vertigo on Inflammatory and Immunologic Laboratory Markers.

The neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and mean platelet volume (MPV) are markers of subclinical inflammation and atherothrombosis. We investigated whether these easily accessible blood count parameters are affected by peripheral vertigo (PV). We studied 142 patients who were diagnosed with PV and referred to our hospital along with 135 healthy patients who were free of inflammation as a control group. The patient group was divided into 3 study groups depending on the presence of benign paroxysmal positional vertigo (BPPV): BPPV, vestibular dysfunction (VD), and BPPV + VD. The total patient group and 3 subgroups were compared to the control group with respect to the NLR, PLR, and MPV. The NLR and PLR were calculated by dividing the neutrophil and platelet values by the lymphocyte value. Of 142 patients, 43, 71, and 28 patients comprised the BPPV, VD, and BPPV + VD groups, respectively. There was no statistically significant difference (P > .05) in the NLR, PLR, or MPV between the main patient group or the individual patient subgroups and the control group. Our findings suggest that NLR, PLR, and MPV do not change significantly either in BPPV or in other peripheral vestibular disorders.

Plasma levels of inflammatory mediators in vestibular migraine.

Objectives: Vestibular migraine (VM) is an under-recognized entity with substantial burden for the individual and society. The underlying mechanism of VM and its distinction from other migraine mechanisms still remain unclear. Inflammatory pathways have been suggested to contribute to vestibular migraine. Our aim was to further investigate the possible role of inflammation in the pathophysiology of VM.Methods: We recruited 30 patients with VM diagnosed according to ICHD-3 criteria and 50 gender- and age-matched controls. Blood samples were obtained from 11 VM patients during an attack and from 13 VM patients under prophylactic treatment. Plasma levels of calcitonin gene related peptide (CGRP), neurokinin A (NKA), substance P (SP), NLRP1, NLRP3, caspase-1, IL-1ß, IL-6, TNF-α and NFκB were measured by ELISA.Results: IL-6 levels were significantly reduced in VM patients, whereas levels of other inflammation parameters were comparable to those of healthy controls. Levels of inflammatory mediators were not correlated with clinical parameters. Likewise, there were no significant differences among VM patients with and without headache attack and prophylactic treatment.Conclusion: Our results argue against involvement of systemic inflammation in the pathophysiology of VM.

Diagnostic Values of Neutrophil and Neutrophil to Lymphocyte Ratio in Distinguishing between Acute Cerebral Infarction and Vertigo.

BACKGROUND: Vertigo and acute cerebral infarction (ACI) patients show similar symptoms such as dizziness and imbalance. This study was to investigate the diagnostic values of neutrophil counts and neutrophil to lymphocyte ratio (NLR) in distinguishing patients with ACI from those with vertigo. METHODS: This retrospective study was performed and data were gathered from medical records of patients with vertigo symptoms from the Department of Emergency and Neurology Clinics who were admitted to the Fourth Affiliated Hospital Zhejiang University School of Medicine between August 2017 and January 2019. Of the 173 patients with vertigo symptoms, 111 non-ACI vertigo patients (vertigo group) and 62 cases diagnosed with ACI (ACI group) were enrolled in this study. The neutrophil counts, lymphocyte counts, platelet counts, NLR, and PLT to lymphocyte ratio (PLR) within 24 hours after admission were compared between the two groups. Student's t-test of independent samples was adopted for the comparison of the mean between two groups. The neutrophil counts and NLR were evaluated by comparing the areas under the receiver operating characteristic curve (AUC) in distinguishing patients with ACI from those with vertigo. Comparison of AUC was performed using the Z-test. RESULTS: The neutrophil counts and NLR were significantly increased in the ACI group compared with the vertigo group (all p < 0.05), while there were no significant statistical differences of the lymphocyte counts, platelet counts, and PLR (all p > 0.05); moreover, AUC in distinguishing patients with ACI from those with vertigo was 0.647 (95% confidence interval (CI), 0.570 to 0.718) for neutrophil counts and 0.639 (95% CI, 0.562 to 0.710) for NLR, but there was no significant statistical difference (p > 0.05); finally, the cutoff values were 3.1 x 109/L in distinguishing patients with ACI from those with vertigo (specificity 41.44% and sensitivity 83.87%) for neutrophil counts and 2 (specificity 55.86% and sensitivity 67.74%) for NLR. CONCLUSIONS: As easy-to-obtain inflammatory biomarkers, both neutrophil counts and NLR could demonstrate diagnostic values in distinguishing between ACI and vertigo.

Serum oxidative stress, inflammatory response and platelet activation in patients with vascular vertigo.

The aim of this study was to investigate the correlation and clinical significance of oxidative stress and inflammatory response in vascular vertigo (VV). The subjects were divided into three groups: vascular vertigo (group A), non-vascular vertigo (group B) and controls (group C). The serum levels of IL-6 (interleukins-6), SOD (superoxide dismutase), MDA (malondialdehyde) and TNF-α (tumor necrosis factor-α) and CD62P (also called P-Selectin) activation rates were determined and compared among the three groups. The levels of IL-6, TNF-α, MDA and CD62P in group A were significantly higher than those of group B and group C (P less than 0.05). The SOD level of group A was lower than that of group B and group C (P less than 0.05). There was no significant difference between groups B and C in IL-6, TNF- αMDA, SOD and CD62P (P>0.05). In patients with vascular vertigo, TNF-α levels had a weak linear correlation with those of low-density lipoprotein (P = 0.025, r = 0.312). There was no linear correlation between TNF-α and SOD in patients with VV and non-VV. The occurrence of inflammatory reaction and oxidative stress may cause abnormal lipid metabolism in the body and promote the occurrence of VV, and platelet activation may be involved in its formation.

Clinical and laboratory factors related to acute isolated vertigo or dizziness and cerebral infarction.

OBJECTIVE: To clarify the relationship of clinical factors with isolated vertigo or dizziness of cerebrovascular origin. METHODS: Clinical data of patients admitted in East Hospital from Jan. 2015 to Apr. 2016, whose complaint were acute vertigo or dizziness were retrospectively collected. All patients arrived at the emergency department within 24 hr of symptom onset, had no acute ischemic lesion first CT and NIHSS score of 0. Patients were divided into cerebral infarction group and noncerebral infarction group according to subsequent cerebral imaging results and clinical and laboratory factors related to cerebral infarction were analyzed. RESULT: 51.6% of patients were female (n = 141). 46 patients (16.8%) were diagnosed with acute cerebral infarction. Baseline demographic data of the two groups was not significantly different. Univariate analysis found that history of smoking (p = 0.009), headache (p = 0.028), unsteadiness (p = 0.009), neuron specific enolase (p = 0.001), and vertebral artery abnormalities found on imaging (p = 0.009) were the significant difference between two groups. Increased neuron specific enolase (p = 0.005) and an abnormal vertebral artery (p = 0.044) were significant on multivariate analysis. CONCLUSIONS: 16.8% of acute isolated vertigo or dizziness presentations were diagnosed with acute cerebral infarction. Increased serum neuron specific enolase and vertebral artery abnormalities were the strongest indicators of acute cerebral infarction.

Utility of Neutrophil-to-Lymphocyte Ratio (NLR) as a Predictor of Acute Infarction in New-Onset Acute Vertigo Patients Without Neurologic and Computed Tomography Abnormalities.

BACKGROUND: Neutrophil-to-lymphocyte ratio (NLR) has been used as a predictive marker for various conditions. However, there are no previous studies about NLR as a prognostic marker for acute infarction. OBJECTIVE: To evaluate the potential utility of NLR as a predictor of acute infarction in acute vertigo patients without neurologic and computed tomography (CT) abnormalities. METHODS: We conducted a prospective, observational study in the Emergency Department (ED) between January 2015 and December 2016. All patients underwent physical examination, laboratory tests, CT, and magnetic resonance imaging (MRI). Results of the initial and follow-up MRI with clinical progress note were considered as the reference standard. Statistically, multivariate logistic regression analysis and receiver operating characteristic (ROC) curve were used. RESULTS: Thirty-five (25.9%) patients were diagnosed with acute infarction and 100 (74.1%) patients were diagnosed with peripheral vertigo. Horizontal nystagmus (p = 0.03; odds ratio 0.22) and NLR (p = 0.03; odds ratio 5.4) were significant factors for the differential diagnosis of acute infarction and peripheral vertigo. NLR > 2.8 showed the greatest area under the ROC curve (AUC; 0.819), optimal sensitivity (85.7%), and specificity (78.0%). NLR > 1.4 showed the highest sensitivity (97.1%) and relatively low specificity (41%). The absence of horizontal nystagmus increased the specificity (81.0%) and AUC (0.844). CONCLUSIONS: A combination of NLR > 2.8 and the absence of horizontal nystagmus is sufficiently specific for acute infarction in an ED patient with acute vertigo; thus, further testing with MRI is indicated. NLR < 2.8 by itself or combined with the presence of horizontal nystagmus is not sufficiently sensitive to rule out the need for further testing.

Accompanying migrainous features in pediatric migraine patients with restless legs syndrome.

The present study aimed to examine the frequency of restless legs syndrome (RLS) in pediatric patients with migraine and tension-type headache (TTH) and to investigate accompanying migrainous symptoms, sleep characteristics, as well as levels of serum ferritin between the pediatric migraine patients with RLS and those without RLS. We included 65 consecutive patients diagnosed with migraine, 20 patients with TTH, and 97 headache-free children in our study. Demographic, clinical, and laboratory data were noted. The presence of a primary headache was diagnosed using the ICHD-II criteria, and RLS was determined with face-to-face interviews conducted by an experienced neurologist based on the revised International RLS Study Group criteria for pediatrics. The frequency of RLS in pediatric migraine and TTH patients was significantly higher than in the controls (p = 0.0001 and p = 0.025, respectively). The frequencies of allodynia, vertigo/dizziness, and self-reported frequent arousals were significantly higher, and serum ferritin levels were significantly lower in migraine patients with RLS compared to those without RLS (p = 0.05, p = 0.028, p = 0.02, and p = 0.038, respectively). Our study suggests that the frequency of RLS is higher in pediatric migraine and TTH patients compared to controls. Therefore, pediatric headache patients should be questioned about the presence of RLS, as this co-occurrence may lead to more frequent accompanying migrainous symptoms and sleep disturbances.

Vertigo with a Vestibular Dysfunction in Children During Respiratory Tract Infections.

Sudden balance disorders with violent vegetative symptoms (nausea and vomiting) pose a diagnostic and therapeutic problem. In children vertigo/dizziness with symptoms of vestibular dysfunction is rare, but as vascular etiology is unlikely in children such symptoms arouse concern. This article presents two cases of this type of vertigo. The patients were two boys (6 and 9 years old). They came down with similar symptoms: sudden dizziness, disabled walking, nausea and vomiting, spontaneous nystagmus, and a positive Romberg test. The onset of the balance disorder was preceded by respiratory infection: common cold with symptoms of inflammation of the mucous membrane in the nose and throat. Laboratory tests revealed increased levels of C-reactive protein only in the older boy. Neuroinfection and a displacement process were ruled out. Videonystagmography revealed vestibular dysfunction and vestibular neuronitis on the left side.

Serum protein S100ß is a diagnostic biomarker for distinguishing posterior circulation stroke from vertigo of nonvascular causes.

BACKGROUND: In patients presenting with acute vertigo or dizziness, identifying the posterior fossa stroke as the underlying cause can be a major challenge. We therefore evaluated the serum biomarkers for the differential diagnosis of nonvascular vertigo and posterior circulation stroke. METHODS: Of a total of 80 patients, 31 patients had an ischemic stroke in the posterior circulation and 12 infratentorial hemorrhage. Findings in these patients were compared with those in 22 patients with vertigo of nonvascular origin and 15 matched control patients without neurological symptoms. Blood samples drawn <24 h after symptom onset were analyzed for S100 calcium-binding protein B (S100ß), matrix metalloproteinase 9 (MMP-9), soluble vascular cellular adhesion molecule-1 (sVCAM-1), and glial fibrillary acidic protein (GFAP). RESULTS/CONCLUSION: Serum levels of S100ß were significantly higher in stroke patients than in nonvascular vertigo patients. Serum concentrations of MMP-9 tended to be higher in stroke patients, whereas no significant differences among groups were found for sVCAM-1 and GFAP. Receiver-operating characteristic analysis revealed a sensitivity of 94.4% and a specificity of 31.8% for detecting stroke in patients presenting with vertigo for S100ß. S100ß may serve as a biomarker for distinguishing between vertigo of vascular causes and nonvascular, acute vertigo.

Neutrophil-to-lymphocyte ratio in patients with peripheral vertigo: a prospective controlled clinical study.

We aimed to investigate the relationship between peripheral vertigo and inflammation by using the neutrophil-to-lymphocyte ratio (NLR) as an inflammatory marker. We recruited 103 patients with peripheral vertigo (71 women, 32 men; mean age, 39.8 ± 14.7 years) who presented to the Otolaryngology Department of Dumlupinar University Hospital. Vertigo patients with systemic diseases, neurological disorders, malignancy or any inflammatory disease that could alter the NLR were excluded from the study. We also enrolled 103 age- and sex-matched healthy subjects (controls; 82 women, 21 men; mean age, 36.7 ± 13.5 years) who underwent routine checkups in our hospital. The vertigo patients underwent full otolaryngologic and neurologic examinations and audiometric tests to rule out any other pathology causing the peripheral vertigo. NLR was calculated in all subjects and was compared between the patient and control groups. There were no significant differences between the study and control groups in terms of lipid profiles, liver-function tests, white blood cell (WBC) count, hemoglobin level, mean platelet volume, and vitamin B12 and folate levels. The mean NLR was significantly higher in the patients than in the controls (P<0.05). In conclusion, this study, which was the first to investigate the relationship between the NLR and peripheral vertigo, found that the NLR is significantly higher among peripheral vertigo patients than among healthy controls. This result suggests that the NLR is a novel potential marker of stress in peripheral vertigo patients.

Interference from heterophilic antibodies in D-dimer assessment. A case report.

We describe the case of a 3-year-old girl, admitted to the pediatric ward for three repeated episodes of severe migraine associated with vertigo, with onset 1 week after complete remission from an episode of chicken pox (i.e., varicella-zoster virus infection). All radiological and laboratory examinations were normal, except for a markedly elevated value of D-dimer (i.e. 8998 ng/ml; local reference range: < 243 ng/ml), measured with a commercial latex-enhanced immunoturbidimetric assay. After physical and Doppler ultrasound examination, possible presence of thrombosis was ruled out, and the patient was discharged. In the following year, however, her plasma D-dimer values always remained frankly elevated, so that an analytical interference was suspected. A plasma sample was treated with a specific heterophilic antibodies blocking reagent and then assayed along with the untreated sample, with these showing a marked discrepancy of D-dimer values, that is 232 versus 2877 ng/ml. These results, highly indicative for the presence of heterophilic antibodies, are discussed in the light of the serious challenges that this type of analytical interference may pose on quality and reliability of D-dimer testing.

Serum uric acid levels correlate with benign paroxysmal positional vertigo.

BACKGROUND AND PURPOSE: Benign paroxysmal positional vertigo (BPPV) is a frequently encountered condition that can severely affect the quality of life. In this study, we aimed to assess the possible relations between serum uric acid (SUA) levels and BPPV. METHODS: Fifty patients with BPPV, and 40 age- and sex-matched control subjects were enrolled in the study. All the patients and controls underwent a complete audio-vestibular test battery including the Dix-Hallpike maneuver and supine roll test for posterior semicircular canal (PSC) and horizontal semicircular canal, respectively. Routine hematological and biochemical analyses were performed in both groups. In the BPPV group, measurements of SUA levels were repeated 1 month after the vertigo attack. RESULTS: The lipid profiles and SUA levels were higher in patients with BPPV than detected in controls (P < 0.05 and P < 0.001, respectively). Albumin and SUA values were independently associated with BPPV in multiple logistic regression models (P < 0.05 and P < 0.001, respectively). A cutoff value of 4 for SUA level with a sensitivity of 0.72 (0.58-0.84) and a specificity of 0.60 (0.43-0.75) was obtained in the receiver operating characteristic analyses. There was a significant decrement in SUA level 1 month after the vertigo attack compared with the values obtained during the attack (P < 0.001). Among the most involved type of BPPV (PSC BPPV), the right side was affected in 26 patients (57.8%) and the left side in 19 patients (42.2%). SUA levels did not differ statistically in patients with PSC BPPV for either the right or left sides (P > 0.05). CONCLUSIONS: Elevated SUA is positively correlated with BPPV, requiring further efforts to clarify the exact mechanism.

Decreased serum vitamin D in idiopathic benign paroxysmal positional vertigo.

Previous studies have demonstrated an association of osteopenia/osteoporosis with idiopathic benign paroxysmal positional vertigo (BPPV). Since vitamin D takes part in the regulation of calcium and phosphorus found in the body and plays an important role in maintaining proper bone structure, decreased bone mineral density in patients with BPPV may be related to decreased serum vitamin D. We measured the serum levels of 25-hydroxyvitamin D in 100 patients (63 women and 37 men, mean age ± SD = 61.8 ± 11.6) with idiopathic BPPV and compared the data with those of 192 controls (101 women and 91 men, mean age ± SD = 60.3 ± 11.3) who had lived in the same community without dizziness or imbalance during the preceding year. The selection of the controls and acquisition of clinical information were done using the data from the Fourth Korean National Health and Nutrition Examination Survey, 2008. The serum level of 25-hydroxyvitamin D was lower in the patients with BPPV than in the controls (mean ± SD = 14.4 ± 8.4 versus 19.1 ± 6.8 ng/ml, p = 0.001). Furthermore, patients with BPPV showed a higher prevalence of decreased serum vitamin D (<20 ng/ml, 80.0 vs. 60.1 %, p < 0.001) than the controls. Multiple logistic regression analyses adjusted for age, sex, body mass index, hypertension, diabetes, proteinuria, regular exercise and the existence of decreased bone mineral density demonstrated that vitamin D insufficiency (10-20 ng/ml) and deficiency (<10 ng/ml) were associated with BPPV with the odds ratios of 3.8 (95 % confidence interval = 1.51-9.38, p = 0.004) and 23.0 (95 % confidence interval = 6.88-77.05, p < 0.001). Our study demonstrated an association between idiopathic BPPV and decreased serum vitamin D. Decreased serum vitamin D may be a risk factor of BPPV.

The relationship of homocysteine, vitamin B12, folic acid levels with vertigo.

OBJECTIVES: In this study the relationship of serum homocysteine, vitamin B12, folic acid levels and peripheral vestibular dysfunction (PVD) was investigated. PATIENTS AND METHODS: Forty-one patients (31 females, 10 males; mean age 57.34±14.3 years; range 12 to 80 years) who admitted to Baskent University Hospital Ear Nose and Throat Department between the dates of April 2005 - December 2007 with complaint of vertigo were prospectively analyzed and diagnosed using audio-vestibular test, at the same time serum homocysteine, vitamin B12, folic acid measurements was done from the blood samples of patients. The patients were divided into three groups as Meniere's disease, vestibular neurinitis, and benign paroxismal positional vertigo (BPPV) according to the diagnoses and serum homocysteine, vitamin B12, folic acid levels of patients were compared to normal values in and between groups. RESULTS: Of the patients, 29.3% (n=12) were diagnosed with Meniere's disease, 36.6% (n=15) with vestibular neurinitis, and 34.1% (n=14) with BPPV. Serum homocysteine leves of patients were 12.42±3.56 umol/L, 11.32±4.14 umol/L and 10.72±2.95 umol/L (p>0.05) in Meniere's disease, vestibular neurinitis, and BPPV respectively; vitamin B12 levels were 371.58±141.35 pg/ml, 288.13±139.51 pg/ml, 352.14±150.41 pg/ml (p>0.05) respectively and folic acid levels were 8.76±3.2 umol/L, 10.63±6.59 umol/L, 8.8±3.18 umol/L (p>0.05) respectively. The values were similar in all patients. No statistically significant difference was found in and between groups comparing with normal values. CONCLUSION: This is the first prospective study investigating the relationship of serum homocystein, vitamin B12 and folic acid levels with PVD. We found that there is no relationship of homocysteine, vitamin B12, folic acid levels with PVD.

High prevalence of systemic autoimmune diseases in patients with Menière's disease.

BACKGROUND: Autoimmunity appears to be associated with the pathophysiology of Meniere's disease (MD), an inner ear disorder characterized by episodes of vertigo associated with hearing loss and tinnitus. However, the prevalence of autoimmune diseases (AD) in patients with MD has not been studied in individuals with uni or bilateral sensorineural hearing loss (SNHL). METHODS AND FINDINGS: We estimated the prevalence of AD in 690 outpatients with MD with uni or bilateral SNHL from otoneurology clinics at six tertiary referral hospitals by using clinica criteria and an immune panel (lymphocyte populations, antinuclear antibodies, C3, C4 and proinflammatory cytokines TNFα, INFγ). The observed prevalence of rheumatoid arthritis (RA), systemic lupus erythematosus (SLE) and ankylosing spondylitis (AS) was higher than expected for the general population (1.39 for RA, 0.87 for SLE and 0.70 for AS, respectively). Systemic AD were more frequently observed in patients with MD and diagnostic criteria for migraine than cases with MD and tension-type headache (p = 0.007). There were clinical differences between patients with uni or bilateral SNHL, but no differences were found in the immune profile. Multiple linear regression showed that changes in lymphocytes subpopulations were associated with hearing loss and persistence of vertigo, suggesting a role for the immune response in MD. CONCLUSIONS: Despite some limitations, MD displays an elevated prevalence of systemic AD such as RA, SLE and AS. This finding, which suggests an autoimmune background in a subset of patients with MD, has important implications for the treatment of MD.

Frecuencia y pertinencia del perfil lipídico como examen inicial en vértigo periférico / Lipid profile frequency and relevancy as an initial test for peripheral vertigo

Objetivos Determinar la prevalencia de la solicitud del perfil lipídico como ayuda diagnóstica de primera línea en pacientes con impresión clínica de vértigo periférico, así como un análisis de la relación costo-beneficio de dicha solicitud. Métodos Estudio de tipo corte transversal retrospectivo. Revisión de 201 historias de pacientes atendidos en la consulta externa tanto de especialistas como de médicos generales de la Clínica Universitaria Teletón y Casa chía, con diagnóstico de vértigo periférico, en el periodo comprendido entre enero de 2005 y julio de 2008. Resultados Las edades de los pacientes oscilaron entre 6 y 87 años, el 36 % de sexo masculino y el 64 % femenino. El perfil lipídico fue solicitado como prueba diagnóstica inicial para el manejo de vértigo a un 76 % de los pacientes. Los perfiles lipídicos hallados fueron normales en el 80 % de los pacientes a quienes se les solicitó. Se presenta el análisis de la relación costo-beneficio de esta prueba. Conclusiones Existe una alta prevalencia de solicitud de perfil lipídico como estudio de primera línea en el abordaje de pacientes con vértigo periférico, aunque no existe evidencia que avale esta solicitud, se requiere retroalimentación al cuerpo médico tanto de atención primaria como especialistas.

Objective Determining the prevalence of requesting lipid profile as a first-line diagnostic method in patients having a clinical impression of peripheral vertigo and also determining such request's cost- benefit ratio. Methods This was a retrospective cross-sectional study of 201 clinical charts regarding patients diagnosed as having peripheral vertigo at the Teletón teaching hospital's outpatient services in Chía between January 2005 and July 2008. Clinical charts drawn up by both general practitioners and medical specialists at first-time visit were compiled and analyzed Results The patients were aged 6 to 87 years old; 36 % were males and 64 % females. Lipid profile was requested for 76 % of the patients as initial diagnostic method; it was found that 80 % of the results revealed no abnormality. Conclusion Although a high prevalence regarding a request for lipid profile first-line study was found for patients having peripheral vertigo, there was no scientific evidence supporting such requirement. Ordering this kind of study not only increases unnecessary costs concerning diagnostic methods but also involves unjustified treatment. Feedback is needed for both doctors and first attention staff to ensure that this type of practice becomes changed.