Loperamide Toxicity Revealing Apical Hypertrophic Cardiomyopathy.

Loperamide, a µ-opioid receptor agonist, can cause cardiotoxicity by inhibiting the potassium ion channel and slowing cardiomyocyte repolarization. This, in turn, can lead to frequent early afterdepolarizations, the most common mechanism of drug-induced long QT syndrome and torsades de pointes. Apical hypertrophic cardiomyopathy (AHCM) is a nonobstructive hypertrophic cardiomyopathy rarely associated with malignant arrhythmias. We present a case of loperamide-induced malignant ventricular arrhythmia revealing underlying AHCM in a 25-year-old woman with a history of sudden cardiac arrest (SCA) and opioid use. It is important to evaluate for structural heart disease in all patients presenting with SCA, regardless of presumed etiology such as drug-induced cardiotoxicity, to prevent missed opportunities for adequate treatment. Furthermore, the diagnosis of AHCM in SCA warrants further genetic evaluation for variances with a predilection for malignant arrhythmias.

Primary CNS Lymphoma Arising from the 4th Ventricle: A Case Report and Review of the Literature.

A 65-year-old male with a history of ischemic strokes, seizures, and subarachnoid hemorrhage presented with a 4-week history of progressive diplopia, vertigo, nausea, and vomiting. Magnetic resonance imaging (MRI) revealed a 2.5 × 1.8 × 1.7 cm posterior fossa mass arising from the roof of the 4th ventricle extending into the cerebellar vermis. Posterior fossa craniotomy with stereotactic biopsy confirmed a locally invasive diffuse large B-cell lymphoma (DLBCL). Primary central nervous system lymphoma (PCNSL) arising from the 4th ventricle is a rare extranodal manifestation of non-Hodgkin lymphoma (NHL), with few cases documented in the literature. Review of available cases lends support that lymphoma arising from the 4th ventricle has a variable clinical presentation, occurs most commonly in immunocompetent males, and should be on the differential of any immunocompetent adult presenting with a posterior fossa mass. Optimal treatment modalities are based largely on phase 2 clinical trials, and recommended guidelines regardless of anatomic location should be adhered to.

Gastric Siderosis and Ulceration from Intravenous Iron Supplementation Manifesting as Chronic Upper Gastrointestinal Bleeding: A Case Report and Review of the Literature.

Iron deficiency is the most common etiology of anemia worldwide and is often managed with varying methods of iron supplementation. Although rare, oral iron supplementation can perpetuate iron deficiency anemia by causing gastric ulceration and upper gastrointestinal bleeding in high-risk populations. However, this complication has not been previously described with intravenous iron supplementation. We present a case of a 63-year-old male with severe iron deficiency anemia on biweekly intravenous iron infusions and weekly packed red blood cell transfusions who presented with melena over several months. Upper endoscopy demonstrated a clean-based gastric body ulcer and nonbleeding gastric varices. Histology of the gastric ulcer was suggestive of iron-induced gastric mucosal injury. This case demonstrates that frequent utilization of intravenous iron and packed red blood cell transfusions may predispose certain patients to the development of iron-induced gastritis and ulceration.

Selective Enzymatic Digestion of Proteoglycans and Collagens Alters Cartilage T1rho and T2 Relaxation Times.

Our objective was to determine the relationship of T1rho and T2 relaxation mapping to the biochemical and biomechanical properties of articular cartilage through selective digestion of proteoglycans and collagens. Femoral condyles were harvested from porcine knee joints and treated with either chondroitinase ABC (cABC) followed by collagenase, or collagenase followed by cABC. Magnetic resonance images were acquired and cartilage explants were harvested for biochemical, biomechanical, and histological analyses before and after each digestion. Targeted enzymatic digestion of proteoglycans with cABC resulted in elevated T1rho relaxation times and decreased sulfated glycosaminoglycan content without affecting T2 relaxation times. In contrast, extractable collagen and T2 relaxation times were increased by collagenase digestion; however, neither was altered by cABC digestion. Aggregate modulus decreased with digestion of both components. Overall, we found that targeted digestion of proteoglycans and collagens had varying effects on biochemical, biomechanical, and imaging properties. T2 relaxation times were altered with changes in extractable collagen, but not changes in proteoglycan. However, T1rho relaxation times were altered with proteoglycan loss, which may also coincide with collagen disruption. Since it is unclear which matrix components are disrupted first in osteoarthritis, both markers may be important for tracking disease progression.

Septic Shock Caused by Rocky Mountain Spotted Fever in a Suburban Texas Patient with Pet Dog Exposure: A Case Report.

BACKGROUND Rocky Mountain spotted fever (RMSF) is associated with high mortality and requires prompt identification and treatment to ensure better outcomes. CASE REPORT We describe an advanced case of RMSF in a 45-year-old female patient with pet dog exposure who presented with altered mental status, dyspnea, and ataxia progressing to septic shock and acute hypoxic respiratory failure requiring intubation and mechanical ventilation. CONCLUSIONS This case illustrates the importance of keeping RMSF in the differential diagnosis in patient populations outside of the usual geographic areas of incidence in the appropriate clinical setting.

Inhaling Difluoroethane Computer Cleaner Resulting in Acute Kidney Injury and Chronic Kidney Disease.

Difluoroethane is the active ingredient in various computer cleaners and is increasingly abused by teenagers due to its ease of access, quick onset of euphoric effects, and lack of detectability on current urine drug screens. The substance has detrimental effects on various organ systems; however, its effects on the kidneys remain largely unreported. The following case report adds new information to the developing topic of acute kidney injury in patients abusing difluoroethane inhalants. In addition, it is one of the first to show a possible relationship between prolonged difluoroethane abuse and the development of chronic kidney disease in the absence of other predisposing risk factors.

Relationship between T1rho magnetic resonance imaging, synovial fluid biomarkers, and the biochemical and biomechanical properties of cartilage.

Non-invasive techniques for quantifying early biochemical and biomechanical changes in articular cartilage may provide a means of more precisely assessing osteoarthritis (OA) progression. The goals of this study were to determine the relationship between T1rho magnetic resonance (MR) imaging relaxation times and changes in cartilage composition, cartilage mechanical properties, and synovial fluid biomarker levels and to demonstrate the application of T1rho imaging to evaluate cartilage composition in human subjects in vivo. Femoral condyles and synovial fluid were harvested from healthy and OA porcine knee joints. Sagittal T1rho relaxation MR images of the condyles were acquired. OA regions of OA joints exhibited an increase in T1rho relaxation times as compared to non-OA regions. Furthermore in these regions, cartilage sGAG content and aggregate modulus decreased, while percent degraded collagen and water content increased. In OA joints, synovial fluid concentrations of sGAG decreased and C2C concentrations increased compared to healthy joints. T1rho relaxation times were negatively correlated with cartilage and synovial fluid sGAG concentrations and aggregate modulus and positively correlated with water content and permeability. Additionally, we demonstrated the application of these in vitro findings to the study of human subjects. Specifically, we demonstrated that walking results in decreased T1rho relaxation times, consistent with water exudation and an increase in proteoglycan concentration with in vivo loading. Together, these findings demonstrate that cartilage MR imaging and synovial fluid biomarkers provide powerful non-invasive tools for characterizing changes in the biochemical and biomechanical environments of the joint.