Effectiveness of the BDProbeTec ET system for detection of Mycobacterium tuberculosis complex in sputum and bronchoalveolar lavage specimens

ObjectiveThe diagnostic efficacy of the BDProbeTEC ET Mycobacterium tuberculosis (MTB) complex direct detection assay (DTB) performed on bronchoalveolar lavage (BAL) specimens and sputum smears was compared with acid-fast bacilli (AFB) smear microscopy.MethodAFB smear microscopy, DTB and culture results of 286 patients with pulmonary tuberculosis were retrospectively reviewed. A total of 120 patients provided expectorated sputum samples, and 166 patients provided BAL specimens. Culture results and clinical diagnosis were used as gold standards.ResultsThe sensitivity and specificity of the DTB assay in detecting MTB in sputum specimens was significantly higher compared to AFB smear microscopy (83.7% and 82.4%, vs. 75.6%, and 41.2%, respectively). The sensitivity and specificity of the DTB assay in detecting MTB in sputum samples was 77.2% and 100% compared to clinical diagnosis, while AFB smear had a sensitivity and specificity of 70.3% and 26.3%, respectively. Compared to culture, DTB had a sensitivity and specificity of 82.8% and 93.2%, respectively, in detecting MTB from BAL specimens; AFB smear had a sensitivity and specificity of 41.9% and 87.7%, respectively. Compared to clinical diagnosis, DTB had a sensitivity and specificity of 67.2% and 100%, respectively, in detecting MTB from BAL specimens; AFB smear had a sensitivity and specificity of 34.8% and 79.5%, respectively.ConclusionsThe superior performance of the DTB assay relative to AFB smear microscopy makes it a valuable tool to enable early diagnosis of MTB, thereby improving patient care and reducing transmission.     

Predicted outcomes of vaccinating wildlife to reduce human risk of Lyme disease

Vaccination efforts for Lyme disease prevention in humans have focused on wildlife reservoirs to target the causative agent, Borrelia burgdorferi, for elimination in vector ticks. Multiple host species are involved in the transmission and maintenance of the bacterium, but not all host species can be vaccinated effectively. To evaluate vaccinating a subset of hosts in the context of host-tick interactions, we constructed and evaluated a dynamic model of B. burgdorferi transmission in mice. Our analyses indicate that on average, a mouse-targeted vaccine is expected to proportionally reduce infection prevalence among ticks by 56%. However, relative to mouse vaccination, human risk of exposure is dominated by the number of tick bites received per person, the proportion of tick blood meals taken from the highly reservoir-competent white-footed mouse relative to other hosts, and the average number of tick bites per mouse. Variation in these factors reduces the predictability of vaccination outcomes. Additionally, contributions of nonmouse hosts to pathogen maintenance preclude elimination of B. burgdorferi through mouse vaccination alone. Our findings indicate that to increase the impact of wildlife vaccination, reducing tick populations by acaricide application, in addition to targeting additional reservoir-competent host species, should be employed.     

Large parietal midline defect with unusual ridge-like structure at the rim and persistent falcine sinus

Background

Midline cranial defects can be divided into lesions with intracranial tissue herniation (cranium bifidum cysticum) and lesions mainly with ossification failure (cranium bifidum occultum). Herniated cephaloceles mostly require surgical resection, while persisted parietal foramina might become smaller with age.

Clinical case

Here, we report a neonate with large symmetric midline skull defect at high parietal area. A mild bulging mass was noticed. Interestingly, unlike sac herniation, it was surrounded by bony ridges extended from the rim of the calvarial defect, which suggests aberrant ossification. Persistent falcine sinus was also detected. At the corrected age of 11 months, the size of the skull defect had decreased spontaneously, favoring the diagnosis of parietal bone ossification defect. Potential mechanisms resulting in the special appearance of skull bone were discussed.

Conclusion

Incomplete closing of the parietal foramina might be expected due to the aberrant ridge formation. We suggest protective measures for the calvarial defect.     

Sex differences in pain-related symptoms and self-initiated school nurse visits among pre-adolescents

We examined sex differences in self-initiated school nurse visits and pain-associated symptoms in 57 pre-adolescents (36 girls), aged 9-11, with a brief, pain-focused version of the Children's Somatization Inventory (CSI). Using sequential multiple regression, pain symptom scores, sex, and their interaction were analyzed in relation to nurse visits prospectively collected for 1 year. Neither sex, nor pain scores alone, predicted total nurse visits. For girls only, higher pain symptom scores predicted increased total visits and increased visits for complaints with documented physical findings. For both sexes, higher pain symptom scores predicted more visits for complaints without documented physical findings. A complex relationship between sex, pain-related symptoms, and self-initiated nurse visits was found in this pre-adolescent sample. Our findings suggest pain-focused symptom measures may be useful in studies of early predictors of adult pain-related healthcare utilization.     

Immediate changes in feedforward postural adjustments following voluntary motor training

There is limited evidence that preprogrammed feedforward adjustments, which are modified in people with neurological and musculoskeletal conditions, can be trained and whether this depends on the type of training. As previous findings demonstrate consistent delays in feedforward activation of the deep abdominal muscle, transversus abdominis (TrA), in people with recurrent low back pain (LBP), we investigated whether training involving voluntary muscle activation can change feedforward mechanisms, and whether this depends on the manner in which the muscle is trained. Twenty-two volunteers with recurrent LBP were randomly assigned to undertake either training of isolated voluntary activation of TrA or sit-up training to activate TrA in a non-isolated manner to identical amplitude. Subjects performed a trunk perturbation task involving arm movement prior to and after training, and surface and fine-wire electromyography (EMG) recordings were made from trunk and arm muscles. Following a single session of training of isolated voluntary activation of TrA, onset of TrA EMG was earlier during rapid arm flexion and extension, to more closely resemble the responses in pain-free individuals. The magnitude of change in TrA EMG onset was correlated with the quality of isolated training. In contrast, all of the abdominal muscles were recruited earlier during arm flexion after sit-up training, while onset of TrA EMG was further delayed during arm extension. The results provide evidence that training of isolated muscle activation leads to changes in feedforward postural strategies, and the magnitude of the effect is dependent on the type and quality of motor training.