The Poisoned Heart: A Case of Takotsubo Cardiomyopathy Induced by Carbon Monoxide Poisoning.

BACKGROUND: Carbon monoxide is a common environmental toxin, and some patients present with features of cardiac injury in addition to the noxious effects of carbon monoxide poisoning. A very small fraction of those have a transient left ventricular apical ballooning syndrome or Takotsubo cardiomyopathy, both terms are used to define a syndrome that affects the systolic function of the heart. It usually presents with elevated troponin levels with or without electrocardiographic changes. Cardiac angiograms generally illustrate coronary arteries without significant obstruction. CASE REPORT: Here we report the curious case of a 37-year-old Hispanic man brought in for carbon monoxide poisoning, but found to have significantly elevated troponin levels. Echocardiogram demonstrated decreased ejection fraction of 35%. Left heart catheterization 2 days after admission revealed patent coronary arteries, improved ejection fraction to 45%, and wall motion abnormalities plus apical ballooning compatible with Takotsubo cardiomyopathy. The case is unusual because our patient differs from the classically defined elderly, postmenopausal female demographic, and did not experience an emotional crisis that could have provoked this series of events. It is also noteworthy for the fact that the only identifiable trigger was exposure to carbon monoxide. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Carbon monoxide poisoning is a common occurrence resulting in a multitude of annual emergency department visits. Given the known toxic effects of carbon monoxide poisoning on the heart, prompt cardiac workup is important to prevent overlooking a major, although rare, manifestation of carbon monoxide exposure.

A Single-Center Experience and Literature Review of Management Strategies for Clostridium difficile Infection in Hematopoietic Stem Cell Transplant Patients.

INTRODUCTION: The aim of our study is to evaluate risk factors associated with the development of C. difficile infection (CDI) in hematopoietic stem cell transplant (HSCT) patients, determine its incidence and report outcomes of CDI in our patient population. METHODS: We performed a retrospective review of medical records of adult HSCT recipients diagnosed between 2013 and 2016 at our center. Logistic regression models were used to determine the relationship between risk factors and the odds of CDI. RESULTS: The overall incidence of CDI in HSCT patients was 9.4%. The incidence of CDI was higher in allogeneic HSCT (20%) versus autologous HSCT (4.8%). No statistically significant differences in age, gender, cancer type, transplant type were found between those who developed CDI and those who did not. However, patients with CDI had a longer length of stay (25 days) and used more antibiotics (30 days prior to and during admission for HSCT) than non-CDI patients (19 days). Only two of 17 patients (11.8%) with CDI experienced recurrence among 180 patients after HSCT. No patient suffered from toxic megacolon or ileus and no patient underwent colectomy. There was no mortality associated with CDI at our center. CONCLUSION: CDI has an incidence rate of 9.4% in HSCT recipients. Established risk factors including age, gender, cancer type, and transplant type were not identified as risk factors in our population. However, longer LOS and use of greater than four lines of antibiotics were observed among those with CDI compared to those without CDI.

Pomalidomide-Based Regimens for Treatment of Relapsed and Relapsed/Refractory Multiple Myeloma: Systematic Review and Meta-analysis of Phase 2 and 3 Clinical Trials.

INTRODUCTION: Pomalidomide (Pom) has demonstrated synergistic antiproliferative activity in combination regimens as a result of its distinct anticancer, antiangiogenic, and immunomodulatory effects. This review aimed to compare outcome measures of different Pom regimens for relapsed/refractory multiple myeloma. METHODS: A comprehensive literature search identified a total of 1374 studies. Thirty-five studies assessing 4623 subjects met the inclusion criteria: phase 2/3 trial, ≥ 2 prior lines of therapy, and clearly documented efficacy outcomes like overall response rate (ORR), overall survival, and progression-free survival. Statistical analyses for meta-analysis was performed by CMA version 3 and Cochrane Q statistics (P < .05 considered significant, I2 index for heterogeneity). A random effects model was used if there was significant heterogeneity (P ≥ .05 over I2 ≥ 50%). RESULTS: Pooled analysis showed ORR 47.1% across all Pom-based (2- and 3-drug) regimens. Stratified analysis for efficacy outcomes (pooled ORR [%] and mean progression-free survival [months]) are reported. With doublet regimen, Pom with low-dose dexamethasone (LoDex) was the most common regimen (35.7%, 6.1 months), and overall survival was 14.37 months. With triplet regimens, pooled ORR was 61.9% (I2 = 87.3%). These included bortezomib + Pom + LoDex (83.5%, 15.7 months), carfilzomib-Pom + LoDex (77.1%, 15.3 months), Pom + LoDex-bendamustine (74.2%), Pom-dexamethasone-daratumumab (64.5%), Pom + LoDex-cyclophosphamide (59.4%, 9.5 months), and Pom + LoDex-doxorubicin (32%). Leading adverse events were myelosuppression, with mean incidences of grade 3 or higher neutropenia, anemia, and thrombocytopenia of 47.6%, 26.5%, and 20.8%, respectively. Mean incidence of grade 3 or higher nonhematologic adverse events were infections 29.1%, pneumonia 13.8%, and fatigue 10%. CONCLUSION: Three-drug Pom regimens yielded double the response rates compared to Pom + LoDex (pooled ORR, 61.9% vs. 35.7%), with bortezomib + Pom + LoDex and carfilzomib-Pom + LoDex demonstrating better outcomes than other regimens.