Takotsubo Syndrome Presenting as Cardiogenic Shock in Patients With COVID-19: A Case Series and Review of Current Literature.

Takotsubo's syndrome (TTS) is a form of stress cardiomyopathy with a relatively benign long-term course, but may lead to arrhythmias and cardiogenic shock in the acute setting. Despite a recent rise in suspected stress-induced cardiomyopathy, the relationship between the novel coronavirus disease 19 (COVID-19) and TTS is not fully understood. Early recognition of TTS in these patients is important to guide management and treatment. We present 2 cases of TTS arising in the setting of COVID-19 with rapid progression to biventricular heart failure and cardiogenic shock.

A simple colorimetric experiment using mammalian cell culture to study metabolism.

The goal of this laboratory exercise is to give upper-level undergraduate students an introduction to sterile technique in mammalian cell culture and metabolism. The experiment can be completed within a 3-h lab period and can be performed either in conjunction with other biochemistry/metabolism experiments or used as a stand-alone experiment. In this experiment, students are tasked with relating the acidification of cell culture medium to metabolism in order to elucidate the mechanism of action for a compound. Students can relate their experimental results to topics covered on glycolysis and oxidative phosphorylation in upper-level biochemistry classes as well as gain valuable experience relating metabolism to drug discovery.

Atrial Flutter With Exercise-Induced 1:1 Atrioventricular Conduction.

Typical atrial flutter is a common atrial tachyarrhythmia. Symptoms are typically related to the rate of ventricular response. Although atrial flutter with 1:1 atrioventricular conduction is rare, it is important to recognize because it may precipitate rapid hemodynamic compromise. The authors present a case of exercise-induced 1:1 atrioventricular conduction in a patient with typical atrial flutter.

Pauci-Immune Necrotizing and Crescentic Glomerulonephritis with Membranous Lupus Nephritis, Fifteen Years after Initial Diagnosis of Secondary Membranous Nephropathy.

Renal involvement in systemic lupus erythematosus (SLE) is usually immune complex mediated and may have multiple different presentations. Pauci-immune necrotizing and crescentic glomerulonephritis (NCGN) refers to extensive glomerular inflammation with few or no immune deposits that may result in rapid decline in renal function. We report a case of a 79-year-old Hispanic male with a history of secondary membranous nephropathy (diagnosed by renal biopsy 15 years previously) who was admitted with acute kidney injury and active urinary sediment. P-ANCA titers and anti-myeloperoxidase antibodies were positive. The renal biopsy was diagnostic for NCGN superimposed on a secondary membranous nephropathy. A previous diagnosis of SLE based on American College of Rheumatology criteria was discovered via Veteran's Administration records review after the completion of treatment for pauci-immune NCGN. ANCAs are detected in 20-31% of patients with SLE. There may be an association between SLE and ANCA seropositivity. In patients with lupus nephritis and biopsy findings of necrotizing and crescentic glomerulonephritis, without significant immune complex deposition, ANCA testing should be performed. In patients with secondary membranous nephropathy SLE should be excluded.

Sildenafil Induced Acute Interstitial Nephritis.

Acute interstitial nephritis (AIN) is characterized by inflammation of the renal interstitium and usually occurs in a temporal relationship with the medication. We present a case of an Asian male who had nephrotic range proteinuria and presented with acute kidney injury. The patient reported an acute change in physical appearance and symptomatology after the ingestion of a single dose of sildenafil. Renal biopsy was notable for minimal change disease (MCD) with acute and chronic interstitial nephritis. Renal replacement and glucocorticoid therapy were initiated. Renal recovery within six weeks permitted discontinuation of dialysis. AIN superimposed on MCD is a known association of NSAID induced nephropathy. The temporal association and the absence of any new drugs suggest that the AIN was most likely due to the sildenafil. NSAIDs are less likely to have caused the AIN given their remote use. The ease of steroid responsiveness would also suggest another cause as NSAID induced AIN is often steroid resistant. The MCD was most likely idiopathic given the lack of temporal association with a secondary cause. As the number of sildenafil prescriptions increases, more cases of AIN may be identified and physician awareness for this potential drug disease association is necessary.