Faculty Bibliography

BACKGROUND:Primary spontaneous pneumothorax is a common disorder occurring in young adults without underlying lung disease. Although tobacco smoking is a well-documented risk factor for spontaneous pneumothorax, an association between electronic cigarette use (that is, vaping) and spontaneous pneumothorax has not been noted. We report a case of spontaneous pneumothoraces correlated with vaping. CASE PRESENTATION/METHODS:An 18-year-old Caucasian man presented twice with recurrent right-sided spontaneous pneumothoraces within 2 weeks. He reported a history of vaping just prior to both episodes. Diagnostic testing was notable for a right-sided spontaneous pneumothorax on chest X-ray and computed tomography scan. His symptoms improved following insertion of a chest tube and drainage of air on each occasion. In the 2-week follow-up visit for the recurrent episode, he was asymptomatic and reported that he was no longer using electronic cigarettes. CONCLUSIONS:Providers and patients should be aware of the potential risk of spontaneous pneumothorax associated with electronic cigarettes.

BACKGROUND:Although the causes of falls are legion, infectious disease-related factors are not commonly reported in the published literature. We investigated the characteristics of patients presenting to the hospital because of a fall and who were subsequently found to have a coexisting systemic infection (CSI). MATERIALS AND METHODS/METHODS:This was a retrospective study performed at Massachusetts General Hospital, using the electronic database of adult patients receiving care during the period January 1, 2000 through December 31, 2014. Cases were initially screened by using billing codes for "fall," "sepsis," "bacteremia" and "systemic inflammatory response syndrome" (SIRS). Evaluable patients had documented CSI in the setting of a fall. RESULTS:Of 161 evaluable patients, 84 (52.2%) were female. The mean age was 75. 2 years (range: 35-102 years, median = 78 years). Fall was considered "mechanical" (e.g., tripped by a rug) in 106 (65.8%) cases, with 126 (78.3%) patients living at home. SIRS criteria were met on initial healthcare encounters of 66 (40.1%) patients. Urinary and lower respiratory tract infections were the most common infectious disease conditions (71 [44.1%] and 37 [23.0%] cases, respectively). Bacteremia was seen in 64 (39.8%) cases. Staphylococcus aureus was the most common cause of bacteremia (21 cases, 31.3% of bloodstream isolates). CSI was not initially suspected by providing clinicians in 64 (39.8%) patients. CONCLUSIONS:Falls associated with CSIs are often considered "mechanical" in nature, and they frequently fail to meet the SIRS criteria on initial presentation. Aside from its commonly recognized causes, falls may be an atypical manifestation of a systemic infection.

BACKGROUND:Myocardial extravascular extracellular volume fraction (Ve) measures quantify diffuse fibrosis not readily detectable by conventional late gadolinium (Gd) enhancement (LGE). Ve measurement requires steady state equilibrium between plasma and interstitial Gd contrast. While a constant infusion produces steady state, it is unclear whether a simple bolus can do the same. Given the relatively slow clearance of Gd, we hypothesized that a bolus technique accurately measures Ve, thus facilitating integration of myocardial fibrosis quantification into cardiovascular magnetic resonance (CMR) workflow routines. Assuming equivalence between techniques, we further hypothesized that Ve measures would be reproducible across scans. METHODS:In 10 volunteers (ages 20-81, median 33 yr, 3 females), we compared serial Ve measures from a single short axis slice from two scans: first, during a constant infusion, and second, 12-50 min after a bolus (0.2 mmol/kg gadoteridol) on another day. Steady state during infusion was defined when serial blood and myocardial T1 data varied <5%. We measured T1 on a 1.5 T Siemens scanner using a single-shot modified Look Locker inversion recovery sequence (MOLLI) with balanced SSFP. To shorten breath hold times, T1 values were measured with a shorter sampling scheme that was validated with spin echo relaxometry (TR = 15 sec) in CuSO4-Agar phantoms. Serial infusion vs. bolus Ve measures (n = 205) from the 10 subjects were compared with generalized estimating equations (GEE) with exchangeable correlation matrices. LGE images were also acquired 12-30 minutes after the bolus. RESULTS:No subject exhibited LGE near the short axis slices where Ve was measured. The Ve range was 19.3-29.2% and 18.4-29.1% by constant infusion and bolus, respectively. In GEE models, serial Ve measures by constant infusion and bolus did not differ significantly (difference = 0.1%, p = 0.38). For both techniques, Ve was strongly related to age (p < 0.01 for both) in GEE models, even after adjusting for heart rate. Both techniques identically sorted older individuals with higher mean Ve values. CONCLUSION/CONCLUSIONS:Myocardial Ve can be measured reliably and accurately 12-50 minutes after a simple bolus. Ve measures are also reproducible across CMR scans. Ve estimation can be integrated into CMR workflow easily, which may simplify research applications involving the quantification of myocardial fibrosis.