What does the video head impulse test tell us about post-caloric vestibular recruitment?

Abstract Objective: The vestibular recruitment observed in caloric testing is a new tool in the study of the vestibulo-ocular reflex. This study aimed to determine the sensitivity and specificity of the video head impulse test to detect post-caloric vestibular recruitment. Method: In this cross-sectional study, all participants underwent the standard otoneurological assessment of the service, caloric test, and video head impulse test. A non-linear mixed model was used to test for associations. Results: The study group consisted of 250 (89 male and 161 female) patients, with a mean age of 54.84 years. The control group comprised 35 participants, 18 men and 17 women, with a mean age of 40.42 years. Sex and age had no effect on group responses. There was no difference between the study and control groups regarding the interaction between recruitment and gain (p = 0.7487); recruitment and overt (p = 0.7002) and covert saccades (p = 1.0000); and recruitment and anti-compensatory saccades in the contralateral ear (p = 0.3050). The video head impulse test had a sensitivity of 51% and a specificity of 50% as a predictor of post-caloric recruitment. Conclusion: The video head impulse test results showed no relevance in predicting post-caloric vestibular recruitment.

What does the video head impulse test tell us about post-caloric vestibular recruitment?

OBJECTIVE: The vestibular recruitment observed in caloric testing is a new tool in the study of the vestibulo-ocular reflex. This study aimed to determine the sensitivity and specificity of the video head impulse test to detect post-caloric vestibular recruitment. METHOD: In this cross-sectional study, all participants underwent the standard otoneurological assessment of the service, caloric test, and video head impulse test. A non-linear mixed model was used to test for associations. RESULTS: The study group consisted of 250 (89 male and 161 female) patients, with a mean age of 54.84 years. The control group comprised 35 participants, 18 men and 17 women, with a mean age of 40.42 years. Sex and age had no effect on group responses. There was no difference between the study and control groups regarding the interaction between recruitment and gain (p = 0.7487); recruitment and overt (p = 0.7002) and covert saccades (p = 1.0000); and recruitment and anti-compensatory saccades in the contralateral ear (p = 0.3050). The video head impulse test had a sensitivity of 51% and a specificity of 50% as a predictor of post-caloric recruitment. CONCLUSION: The video head impulse test results showed no relevance in predicting post-caloric vestibular recruitment.

Antigen-triggered interferon-γ and interleukin-10 pattern in cured mucosal leishmaniasis patients is shaped during the active phase of disease.

An exacerbated type 1 response to leishmanial antigens is the basis of tissue destruction observed in mucosal leishmaniasis (ML). After therapy, a persistent production of high levels of inflammatory cytokines can confer a poor prognosis. Herein we investigated whether the clinical conditions defined during the active phase of ML affect the magnitude of long-term anti-Leishmania immune response. Twenty clinically cured ML cases were studied. Peripheral blood mononuclear cells (PBMC) were cultured with L. braziliensis antigens (Lb-Ag), Toxoplasma gondii antigens (Tg-Ag), concanavalin-A (Con-A) or medium alone, and the lymphocyte proliferative response and cytokine secretion were quantified. Medical records were reviewed for Montenegro skin test (MST) during diagnosis, duration of ML disease or time elapsed after clinical cure. The duration of disease was correlated positively with MST (r = 0·61). Lb-Ag induced interferon (IFN)-γ was correlated positively with duration of illness (r = 0·69) as well as the frequency of secreting cells [enzyme-linked immunospot (ELISPOT)] assay. No association was observed for Tg-Ag or Con-A. Disease duration was correlated negatively with interleukin (IL)-10 production (r = -0·76). Moreover, a negative correlation between length of time after clinical cure and TNF levels (r = -0·94) or the IFN-γ : IL-10 ratio (r = -0·89) were also seen. We suggest that the magnitude of the IFN-γ inflammatory response triggered by ML can be driven by the time of leishmanial antigens exposition during the active phase of the disease. This pattern could persist even long-term after cure. However, despite IFN-γ levels, the decrease of the TNF and IFN-γ : IL-10 ratio reflects the control of proinflammatory responses achieved by cure of ML, possibly preventing disease relapses.

Hypersensitivity to inhalants and food in balance disturbances.

INTRODUCTION: The prevalence of allergy in patients with Menière's disease was established as approximately 41.6% for inhalants and 26.6% for food. These are elevated values in relation to the prevalence of allergy in the general population, which varies from 9% to 30% for inhalants (in Brazil) and from 1% to 3% for food. OBJECTIVES: To evaluate the prevalence of type I hypersensitivity reactions to inhalants and food in the patients of the Neurotology Sector of the 'Hospital das Clinicas' of the University of São Paulo Medical School and to describe vestibular symptoms of these patients. METHOD: Seventy-five patients with imbalance due to peripheral origin were evaluated by a questionnaire for the clinical characterization of the cochleo-vestibular symptoms and underwent the prick test for 13 inhalants and 5 food stuffs. RESULTS: Twenty-five (33.3%) patients presented positive prick tests and, at least, one food allergen. Four patients presented positive prick tests without allergy symptoms. The prevalence of the complaint of rotatory dizziness was similar among the patients with positive and negative prick tests. CONCLUSION: The prevalence of Type I hypersensitivity reactions to inhalants and food in the population evaluated was greater than in the general population. The vestibular symptoms did not differ among the patients with either positive or negative prick tests. However, a larger sample size should be obtained for the data to be more reliable.

Can interferon-gamma and interleukin-10 balance be associated with severity of human Leishmania (Viannia) braziliensis infection?

Suitable levels of interferon (IFN)-gamma and interleukin (IL)-10 seem to favour the outcome of cutaneous leishmaniasis (CL), while high IFN-gamma and low IL-10 production are associated with severity of mucosal leishmaniasis (ML). Considering that cytokine balance is important for the maintenance of protective responses in leishmaniasis, our aim was to investigate leishmanial antigens-induced IFN-gamma and IL-10 levels maintained in healed individuals who had different clinical outcomes of Leishmania infection. Thirty-three individuals who recovered from L. braziliensis infection were studied: cured CL (CCL), cured ML (CML), spontaneous healing of CL (SH) or asymptomatic individuals (ASY). Cytokines were quantified by enzyme-linked immunosorbent assay (ELISA) in culture supernatants of L. braziliensis-stimulated peripheral blood mononuclear cells (PBMC). IFN-gamma levels were higher in CML (7593 +/- 5994 pg/ml) in comparison to SH (3163 +/- 1526 pg/ml), ASY (1313 +/- 1048 pg/ml) or CCL (1897 +/- 2087 pg/ml). Moreover, cured ML cases maintained significantly lower production of IL-10 (127 +/- 57.8 pg/ml) in comparison to SH (1373 +/- 244 pg/ml), ASY (734 +/- 233 pg/ml) or CCL (542 +/- 375 pg/ml). Thus, a high IFN-gamma/IL-10 ratio observed in CML can indicate unfavourable cytokine balance. On the other hand, no significant difference in the IFN-gamma/IL-10 ratio was observed when CCL individuals were compared to SH or ASY subjects. In conclusion, even after clinical healing, ML patients maintained a high IFN-gamma/IL-10 secretion profile in response to leishmanial antigens. This finding can explain a delayed down-modulation of exacerbated inflammatory responses, which can be related in turn to the necessity of prolonged therapy in ML management. Conversely, lower IFN-gamma/IL-10 balance observed in CCL, SH and ASY individuals can represent a better-modulated immune response associated with a favourable prognosis.

Predicting preterm delivery in asymptomatic patients with prior preterm delivery by measurement of cervical length and phosphorylated insulin-like growth factor-binding protein-1.

OBJECTIVE: To evaluate the efficacy of cervical length measurement in combination with a bedside assessment of phosphorylated insulin-like growth factor-binding protein-1 (phIGFBP-1) as a predictor of preterm delivery in asymptomatic pregnant women with a history of preterm birth. METHODS: Cervical length was measured using transvaginal sonography at 22-24 weeks of gestation in 105 singleton pregnancies and a rapid strip test was performed to detect phIGFBP-1 in cervical secretions from 24 to 34 weeks. Receiver-operating characteristics (ROC) curves were constructed to compare the performance of phIGFBP-1 at different gestational ages, and cervical length at 22-24 weeks, in predicting preterm delivery. RESULTS: The rate of spontaneous delivery before 37 and 34 weeks was 23.8% and 11.4%, respectively. Women with cervical lengths less than 20 mm had a risk of spontaneous preterm delivery before 34 and 37 weeks of 43.5% and 69.6%, respectively. The performance of phIGFBP-1 levels as a predictor of preterm delivery was significantly higher when the test was carried out at 30 weeks' gestation. Cervical assessment in combination with phIGFBP-1 at 30 weeks had the steepest ROC curve (area under the curve=0.93; 95% CI, 0.88-0.98, P<0.001). CONCLUSION: Both cervical length and phIGFBP-1 measurement are useful in the prediction of preterm delivery in patients with a history of preterm birth and the combined method of measuring cervical length at 22-24 weeks and phIGFBP-1 at 30 weeks improves upon either method used alone.

Use of hyaluronidase for cervical ripening: a randomized trial.

OBJECTIVE: To investigate the action of intracervical administration of hyaluronidase (HAase) as an inductor of cervical ripening on an outpatient basis. METHODS: A randomized double-blind trial was conducted with 168 pregnant women at term, Bishop score (BS)<5, normal fetal vitality and no uterine contractions. An evaluation was performed at the first visit, when either 20,000 UI of lyophilized HAase (5 ml) or placebo was administered via cervical injection. After 48 h, if the BS remained<5, a second dose was administered. The primary outcome was the BS after 48 h or 96 h. The outcome was considered positive when BS>/=5. RESULTS: The results indicate that the proportion of positive response for the HAase group (55%) after 48 h is significantly higher (p<0.0001) than the corresponding proportion for the placebo group (7%) with an absolute risk reduction (ARR) of 48%=55-7% (95%CI=40-56%). After 96 h, these proportions are 93% in the Haase group and 22% in the placebo group (p<0.0001, ARR=71%, 95%CI=61-81%). The average duration of labour for the nulliparae in the HAase group (6.5h) is significantly smaller (p<0.0001) than for those under placebo (12.0 h) with an absolute difference of 5.5h (95%CI=4.6-6.4h). For the multiparae, the results are 4.3h for the HAase patients versus 9.5h for the placebo patients (p<0.0001) with an absolute difference of 5.2h (95%CI=4.1-6.3h). The proportion of vaginal deliveries for women who received HAase was 82% versus 51% for the placebo group (p=0.0007, ARR=31%, 95%CI=19-44%). The proportion of vaginal deliveries for patients with prior cesareans in the HAase group (69%) was also significantly higher (p<0.0001) than that corresponding to the placebo group (13%) with ARR=56% (95%CI=26-86%). No uterine hyper stimulation occurred in the study. CONCLUSION: We detected significant associations between intracervical injection of HAase and ripening of the cervix, as well as with shorter duration of labour and larger chance of vaginal delivery, suggesting that this is a simple, effective and safe method even for women with prior cesarean.

Bilateral vestibular loss after caloric irrigation: clinical application of vestibular rehabilitation.

UNLABELLED: Bilateral vestibular loss is a rare diagnosis among patients with dizziness and imbalance. Nevertheless, symptoms are often disabling and therapy has yet to be established. AIM: To evaluate and describe the clinical outcome of patients with imbalance due to bilateral vestibular loss after a caloric test treated with vestibular rehabilitation. STUDY DESIGN: Retrospective case report. METHOD: Pre- and post-treatment outcomes were evaluated in 8 individuals suffering from post-caloric bilateral vestibular paresis who were submitted to vestibular rehabilitation. RESULTS: Clinical improvement after vestibular rehabilitation was observed in 7 (87.5%) of the 8 patients. CONCLUSION: Although complete compensation for bilateral vestibular loss is not expected, vestibular rehabilitation may be used as a therapeutic method in these patients.

Cervical length at 11-14 weeks' and 22-24 weeks' gestation evaluated by transvaginal sonography, and gestational age at delivery.

OBJECTIVE: To compare cervical length measurements obtained at 11 to 14 weeks and 22 to 24 weeks of gestation in an unselected group of pregnant women and to correlate the measurements with time of delivery. METHODS: This was a prospective study involving 529 pregnant women attending for routine antenatal care who underwent transvaginal scans at 11-14 weeks and 22-24 weeks for evaluation of cervical length. The mean cervical length was calculated at both stages of gestation and lengths were compared between groups which delivered at term or prematurely, this being defined as delivery before 37 completed weeks of gestation. RESULTS: The mean cervical lengths at 11-14 and 22-24 weeks were, respectively, 42.4 mm and 38.6 mm. Cervical length at 11-14 weeks was not significantly different between the groups which delivered at term (42.7 mm) and preterm (40.6 mm). However, at the 22-24-week evaluation, cervical length was significantly shorter in the group which had a preterm delivery than in that which had a term delivery (26.7 mm and 39.3 mm, respectively; P = 0.0001). In the group of women with a previous history of one or more preterm deliveries, there was a greater shortening in cervical length from the first to the second evaluation than there was in the group of women with no previous history of preterm delivery. This shortening was also more pronounced in the group which delivered prematurely (from 40.6 mm to 26.7 mm) than in that which delivered at term (from 42.7 mm to 39.3 mm). CONCLUSION: There is a spontaneous shortening in the pregnant cervix from the first to the second trimester of pregnancy. The shortening is more rapid in pregnant women who deliver prematurely and who have a history of previous preterm delivery.

Treating vertigo with vestibular rehabilitation: results in 155 patients.

Balance is fundamental to our daily activities and the vestibular system, together with vision and proprioceptive functions, are the main structures involved in this process. Dizziness is the main clinical manifestation of malfunction of these systems. The mechanisms of vestibular compensation are one of the most studied aspects since they play an important role in the patient's everyday activities. In this retrospective description of a series of cases the authors present their results in 155 patients that underwent a program of vestibular rehabilitation (VR). The program, first described by Cawthorne and Coosey, is based on mechanisms of potentiation of the cervico-ocular reflex and substitution of the lost vestibular cues for visual and somatosensory cues. The results were satisfactory (remission or partial cure) in 75.5% of the patients, with an average treatment time of up to 2 months and 5 or fewer sessions performed in most of the cases. The results were somewhat inferior in those cases in which a central vestibular lesion or more than one etiologic factor was present. The results of a subgroup of elderly patients (age > 65 years) were similar to those of the total number of studied subjects. Vestibular rehabilitation, associated to the specific etiological treatment, appears to be a very useful tool in the management of patients suffering from dizziness of all ages, although different clinical responses to the therapy may vary according to the presence of a central or a peripheral vestibular lesion or multiple etiological factors.

Morphological and functional study of the cochlea after administration of estrogen and progesterone in the guinea pig.

The aim of this study was to analyze the morphological cochlear changes and auditory function observed after the administration of estrogen or progesterone or both. Sixty-two guinea pigs were divided into four groups that received estrogen (group 1), progesterone (group 2), estrogen and progesterone (group 3), and saline solution (controls, group 4), respectively. The auditory evaluation consisted of brainstem evoked response audiometry, performed before and after drug administration. Structural analysis was based on histological hematoxylin and eosin staining preparations. Our results showed changes in latency and amplitude of waves in the study groups that received estrogen or progesterone. The main histological changes observed were inflammatory infiltrate and vacuolization of the stria vascularis. Our results suggest that both estrogen and progesterone lead to morphological and physiological lesions of the cochlea, the degree of the observed lesions depending not only on the presence of these hormones but also on the proportion between them.

Lidocaine test in patients with tinnitus: rationale of accomplishment and relation to the treatment with carbamazepine.

OBJECTIVES: There is strong evidence in the literature about the effect of local anesthetics such as lidocaine in controlling tinnitus; these agents act by stabilizing hair cell membrane and cochlear nerve fibers. However, the effect of intravenous lidocaine is transient, and its oral analog (tocainide) does not have the same efficacy for long-term treatment in patients with tinnitus. Some oral anti-epileptic drugs (carbamazepine, for instance) have been used alternatively in several studies. The aim of this work is to evaluate the response to intravenous lidocaine in patients with intractable tinnitus and the effect of oral carbamazepine in long-term maintenance of tinnitus relief. PATIENTS AND METHODS: We studied prospectively 50 patients (28 females and 22 males; mean age 50.9 years) who underwent the lidocaine test, performed by a 3-min intravenous infusion of 2% lidocaine chloridrate. The patients who experienced any relief after the test started treatment with oral carbamazepine in ascending dosages (50-600 mg/day). RESULTS: The results were classified as tinnitus abolition (18%), marked relief (32%), partial relief (26%), unchanged (22%), or worsening (2%). The lidocaine test showed favorable results in 76% of patients, especially those with bilateral tinnitus (P < 0.001). Afterwards, 50% of patients treated with carbamazepine maintained the improvement of tinnitus (P = 0.0034). CONCLUSION: The authors conclude that intravenous lidocaine is effective in reducing intractable tinnitus and that there is a close association between lidocaine and oral carbamazepine effects. Therefore, carbamazepine can be used for the treatment of tinnitus when the patient achieves improvement of symptom after the lidocaine test.

Cervical fetal fibronectin in patients at increased risk for preterm delivery.

OBJECTIVE: This study aimed to evaluate fetal fibronectin concentrations in cervical secretions measured by either a rapid immunoassay or an enzyme-linked immunosorbent assay as a tool for the screening of premature delivery in otherwise asymptomatic pregnant women at high risk for prematurity. STUDY DESIGN: One hundred two pregnant women at high risk for premature delivery were followed up. Samples of the cervical secretion were taken every 2 weeks between the twenty-fourth and the thirty-fourth weeks of pregnancy. The samples were obtained from the ectocervix with two swabs. One cervical sample was used for the immediate-reading membrane test, and the other one for the immunoenzyme test. The correlation between the presence of fetal fibronectin in the cervical secretions and preterm birth was evaluated. In addition, a comparison between tests was made. RESULTS: The rate of preterm birth was 37.25% (38/102). Membrane tests revealed a sensitivity of 73.68% and a specificity of 92.18%; its positive predictive value was 84.84% and the negative predictive value was 85.50%. The enzyme-linked immunosorbent assays revealed a sensitivity of 78.94% and a specificity of 85.93%; its positive predictive value was 76.92%, and the negative predictive value was 87.30%. When compared with each other, the tests were found essentially concordant (p < 0.05). The elapsed time between the last sampling and the occurrence of preterm birth was 2.9 +/- 1.8 weeks. CONCLUSION: The rapid result membrane test is comparable to the standard fetal fibronectin enzyme-linked immunosorbent assays for the detection of fetal fibronectin in cervical secretions between the twenty-fourth and thirty-fourth weeks of gestation. Moreover, both assays were found to be good tools for the prediction of premature delivery in asymptomatic pregnant women at high risk for prematurity. The availability of a rapid search for the presence of cervical fetal fibronectin should improve our ability to efficiently identify patients at risk for preterm delivery to discriminate between such patients and those with benign Braxton Hicks contractions.

PIP: Researchers evaluated the comparative effectiveness of measuring fetal fibronectin concentrations in cervical secretions by either a rapid immunoassay or an enzyme-linked immunosorbent assay as a tool for the screening of premature delivery in otherwise asymptomatic pregnant women at high risk for prematurity. Cervical secretion samples from the ectocervix were taken every two weeks between the 24th and the 34th week of pregnancy from 102 pregnant women at high risk for premature delivery. The samples were obtained with two swabs. One sample was used for the immediate-reading membrane test while the other was used for the immunoenzyme test. There was a 37.25% rate of preterm birth. Membrane tests yielded a 73.68% sensitivity and a 92.18% specificity, with a positive predictive value of 84.84% and a negative predictive value of 85.50%. The enzyme-linked immunosorbent assays were 78.94% sensitive and 85.93% specific, with a positive predictive value of 76.92% and a negative predictive value of 87.30%. The two tests were concordant with each other. There was a mean of 2.9 weeks between the last sampling and the occurrence of preterm birth. The rapid result membrane test is comparable to the standard fetal fibronectin enzyme-linked immunosorbent assays for the detection of fetal fibronectin in cervical secretions between the 24th and the 34th weeks of pregnancy.