MRI of Suspected Lower Extremity Musculoskeletal Infection in the Pediatric Patient: How Useful Is Bilateral Imaging?

322 and electrocution in pregnancy, data were sparse. Some studies have suggested that maternal and fetal mortality approach 100% for burns $ 40% of total body surface area, with any associated smoke inhalation injury increasing mortality risk. Likewise, case series of electrocutions in pregnancy suggested that fetal mortality rates approach 75% in severe electrocution, though minor electrocutions in the home have no effect on birth outcomes. In penetrating trauma, entrance wounds anterior and inferior to the uterine fundus were noted to have lower risk of maternal visceral injury but higher risk of fetal injury. [Jasmeet Dhaliwal, MD, MPH Denver Health Medical Center, Denver, CO] Comment: This review article summarizes a broad range of literature on trauma in pregnancy. One of the sobering findings, and one that emergency physicians must keep in mind whenever caring for pregnant trauma patients, is the high incidence of domestic violence. There are many other salient points for emergency physicians, including the importance of early multispecialty involvement, prioritization of maternal resuscitation, and the safe use of limited workups in minor trauma.

, LITHIUM IN THE PREVENTION OF SUICIDE IN MOOD DISORDERS: UPDATED SYSTEMATIC REVIEW AND META-ANALYSIS. Cipriani A, Hawton K, Stockton S, et al. BMJ 2013;346:f3646 This meta-analysis evaluated whether or not lithium, when compared to placebo or other psychotropic drugs, reduced the incidence of self-harm, suicide events, or allcause mortality in individuals with mood disorders. Mood disorders included were unipolar depression, bipolar disorder, schizoaffective disorder, dysthymia, and rapid cycling. To be included, patients must have been treated ‘‘long term,’’ which was defined as at least 12 weeks. All ages (pediatric and adult) were included. When comparing lithium to placebo, lithium was more successful at preventing suicides (odds ratio [OR] 0.13, 95% confidence interval [CI] 0.03– 0.66), and reducing all-cause mortality (OR 0.38, 95% CI 0.15–0.95), but did not show statistically significant benefits in preventing self-harm. When comparing lithium to other mood-stabilizing drugs, the only statistically significant result was that lithium was associated with less self-harm than carbamazepine (OR 0.14, 95% CI 0.02–0.83). There was no difference between lithium and any other drug in reducing death or suicide. [Jenelle Holst, MD Denver Health Medical Center, Denver, CO] Comment: Although limited by the quality of the studies included in the larger analysis, this meta-analysis suggests that the use of lithium is still warranted in the management of patients with serious mood disorders. This is an important finding, as the drug does have a narrow therapeutic window and if other less toxic agents were equally efficacious, they might be preferred.

Abstracts , MRI OF SUSPECTED LOWER EXTREMITY MUSCULOSKELETAL INFECTION IN THE PEDIATRIC PATIENT: HOW USEFUL IS BILATERAL IMAGING? Metwalli ZA, Kan JH, Munjal KA, et al. AJR Am J Roentgenol 2013;201:427–32 Magnetic resonance imaging (MRI) is widely utilized for the evaluation of suspected musculoskeletal infections in children, as limitations in the physical examination of children make accurate localization of suspected infection site challenging. Up to two-thirds of cases of osteomyelitis in children occur in the lower extremities. This study sought to identify the frequency of bilateral infections and the impact on management that resulted from having such information available to clinicians. The authors retrospectively identified 165 pediatric patients (average age 7.5 years, range 0–18 years), 65% of whom were male, at a single children’s hospital, over a 1-year period in 2010, that underwent MRI imaging of the bilateral lower extremities. The primary indication for imaging in this study was to evaluate for infection, and studies of children imaged for other reasons were excluded. MRI identified ipsilateral osteomyelitis in 54/165 patients (33%), with 6/54 patients (11%) having contralateral findings, including bilateral osteomyelitis (1/54, 2%), and contralateral myositis (3/54, 6%). Clinical correlation with the patient’s hospital course was evaluated and in no case did contralateral/bilateral findings on MRI change surgical or medical management of the patient. Of the 111 patients that had MRI negative for osteomyelitis, the most frequently encountered alternative diagnoses were septic arthritis (12/ 111, 11%), myositis (25/111, 23%), occult fracture (10/111, 9%), and stress reaction (12/111, 11%). Importantly, no cases of contralateral septic arthritis were identified either with MRI or surgically, and medical or surgical management of MRI findings of the ipsilateral lower extremity did not result in any adverse outcomes to the contralateral lower extremity. Overall, the authors demonstrated a relatively high rate of contralateral findings on MRI in patients both with and without osteomyelitis, but these findings did not alter patient management. [Brian Jekich, MD Denver Health Medical Center, Denver, CO] Comment: Osteomyelitis in children is a challenging diagnosis that cannot be missed. Performing MRI with a wide field of view to include the bilateral lower extremities is technically feasible and may provide additional clinical information. However, screening for bilateral osteomyelitis is of low yield and unlikely to impact clinical management of the patient. This study was limited by its small size and retrospective design. , INDIVIDUALIZATION OF ABDOMINOPELVIC CT PROTOCOLS WITH LOWER TUBE VOLTAGE TO REDUCE I.V. CONTRAST DOSE OR RADIATION DOSE. Hough DM, Yu L, Shiung MM, et al. AJR Am J Roentgenol 2013;201:147–53 The dose of radiation from a computed tomography (CT) scan has decreased with newer scanners and lower tube potential. Lower tube potential allows for patient-specific doses of radiation due to the increased iodine signal with this technology. This study developed a protocol to further reduce the dose of