Osteomyelitis in the neonate. Clinical aspects and the role of radiography and scintigraphy in diagnosis and management

Based on experience with 22 cases of neonatal osteomyelitis in 10 years, the authors suggest these patients can be divided into two groups depending on severity of disease. Premature infants requiring umbilical catheterization and severely ill full-term infants constitute a high-risk group; signs are more overt, multifocal infection and joint involvement more frequent, and severe skeletal deformities more common. The patients in the low-risk group had much milder disease but also presented more difficulty in diagnosis because of the vagueness of the presenting signs. Radiographic examination is essential for diagnosis and follow-up of osteomyelitis, particularly limb deformities. Bone scans should be reserved for situations in which the clinical and radiographic findings are equivocal.     

Carpal avascular necrosis: MR imaging

The authors evaluated the use of magnetic resonance (MR) imaging in diagnosis of avascular necrosis (AVN) of carpal bones by examining 21 patients with wrist pain and two healthy volunteers. MR images were compared with conventional radiographs in every case and with bone scintigrams in 18 cases. MR imaging was slightly less sensitive than bone scintigraphy in depicting AVN, but in patients who were imaged with long repetition time (TR)/long echo time (TE) sequences in addition to short TR/short TE sequences, MR imaging was found to be more specific. While the authors believe that bone scintigraphy remains the screening test of choice for patients with wrist pain and normal plain radiographs, MR imaging promises to add significant diagnostic information in cases in which bone scans are abnormal.     

Carcinomatous involvement of the hilum and mediastinum: computed tomographic and magnetic resonance evaluation

Magnetic resonance (MR) imaging and computed tomography (CT) were compared in 20 patients who had primary lung tumors, and the results were correlated with findings at surgery and pathologic evaluation. Both studies demonstrated a similar ability to detect hilar and mediastinal tumor. MR imaging detected more enlarged nodes in the mediastinum, but in several patients these enlarged nodes did not contain tumor. Consequently, MR imaging has a slightly higher false-positive rate in the evaluation of the mediastinum. Both modalities were highly sensitive, with specificity limited by the presence of enlarged benign lymph nodes in this series of patients.     

The link between allergic rhinitis and asthma: A role for antileukotrienes?

Allergic rhinitis and asthma are both chronic heterogeneous disorders, with an overlapping epidemiology of prevalence, health care costs and social costs in quality of life. Both are inflammatory disorders with a similar pathophysiology, and both share some treatment approaches. However, each disorder has an array of treatments used separately in controlling these atopic disorders, from inhaled corticosteroids, beta₂-agonists and antihistamines to newer monoclonal antibody-based treatments. The present article reviews the shared components of allergic rhinitis and asthma, and examines recent evidence supporting antileukotrienes as effective agents in reducing the symptoms of both diseases.     

Rilmenidine activates postjunctional alpha1- and alpha2-adrenoceptors in the canine saphenous vein

Summary— Experiments were performed to determine the subtypes of alpha-adrenoceptors involved in the contraction induced by rilmenidine in isolated canine cutaneous veins. Rings of saphenous vein (without endothelium) were suspended for the recording of isometric force in physiological salt solution. All experiments were performed in the presence of propranolol (to antagonize betaadrenoceptors), cocaine (to inhibit neuronal uptake) and hydrocortisone (to inhibit extraneuronal uptake). In the presence of rauwolscine (an alpha₂-adrenergic blocker), rilmenidine caused concentration-dependent contractions which were inhibited by prazosin (nonselective alpha₁-antagonist) and by (+)niguldipine (selective alpha_1A-adrenergic antagonist), but not by (-)niguldipine. After treatment with phenoxybenzamine (to alkylate alpha₁-adrenoceptors), rilmenidine evoked contractions of the canine saphenous vein which were antagonized competitively by rauwolscine. The combination of rauwolscine and prazosin did not abolish contractions evoked by the highest concentrations of rilmenidine. Although binding experiments using ³H-idazoxan suggested the existence of a nonadrenergic binding site (around 20% of the total binding), contractile studies failed to demonstrate their involvement in the increases in tension evoked by rilmenidine. These experiments suggest that the contractions evoked by rilmenidine in isolated canine veins are mediated by both alpha_1A- and alpha₂-adrenoceptors.     

An Internet-based store-and-forward video home telehealth system for improving asthma outcomes in children.

The adherence and disease-control outcomes associated with the use of an Internet-based store-and-forward video home telehealth system to manage asthma in children were studied. Pediatric patients with persistent asthma were provided with home computers and Internet access and monitored biweekly over the Internet. All patients were seen in the pediatric clinic at 0, 2, 6, 12, and 24 weeks. Half of the patients received asthma education in person and half via an interactive Web site. Adherence measures were assessed by therapeutic and diagnostic monitoring. Therapeutic monitoring included digital videos of patients using their controller medication inhaler. Diagnostic monitoring included an asthma symptom diary and a video of peak flow meter use. Videos were submitted electronically twice a week by using in-home telemonitoring with store-and-forward technology. Feedback was provided electronically to each patient. Disease control was assessed by examining quality of life, utilization of services, rescue-therapy use, symptom control, satisfaction with home telemonitoring, and retention of asthma knowledge. Patients were randomly assigned to an asthma education group (Internet versus office), and the data were analyzed by comparing results for study days 0-90 and 91-180. Ten children participated. A total of 321 videos of inhaler use and 309 videos of peak flow meter use were submitted. Inhaler technique scores improved significantly in the second study period. Submission of diagnostic monitoring videos and asthma diary entries decreased significantly. Peak flow values as a percentage of personal best values increased significantly. Overall, there was no change in quality of life reported by patients. However, the caregivers in the virtual-education group reported an increase in the patients' quality-of-life survey scores. Emergency department visits and hospital admissions for asthma were avoided. Rescue therapy was infrequent. A high rate of satisfaction with home telemonitoring was reported. Internet-based, store-and-forward video assessment of children's use of asthma medications and monitoring tools in their homes appeared effective and well accepted.     

Chronically obstructed sinonasal secretions: observations on T1 and T2 shortening

Clinically assessed chronic proteinacious sinonasal secretions usually have long T1 and T2 relaxation times reflecting their high water content. However, in some cases variable combinations of short and long T1 and T2 relaxation times are found. To study the causes of these findings, the magnetic resonance (MR) images of 41 patients with surgically proved, chronically obstructed sinonasal secretions were studied. The relative signal intensities on both T1- and T2-weighted sequences of the sinus specimens were correlated with the gross viscosity of the specimens at surgery. Ten specimens were collected that were not contaminated with either blood or saline. UV spectrophotometric analysis of four of these samples excluded the presence of methemoglobin. Total protein content was determined in five samples, and in vitro T1 and T2 values were measured in one sample. These T1 and T2 relaxation times were accurately predicted with use of a standard pure lysozyme protein solution with the same concentration as the specimen. In addition, the observed T1- and T2-weighted signal intensities on the 41 MR images were predicted from an analysis of pure protein solutions. This study concludes that the primary causes of the variable T1 and T2 relaxation times of chronic sinonasal secretions are the macromolecular protein concentration, the amount of free water, and the specimen viscosity. Furthermore, an orderly and predictable transition of these signal intensities occurs over time.