Dynamic Changes of EKG by Severe Hyperkalemia: Transient Left Bundle Branch Block.

Hyperkalemia is one of the most common electrolyte abnormalities seen in clinical practice and the most common life-threatening electrolyte abnormality seen in the emergency department. It is most often due to impaired renal potassium excretion due to acute on chronic kidney disease or the use of drugs that inhibit the renin-angiotensin-aldosterone axis. The most common clinical presentation is muscle weakness and cardiac conduction abnormalities. In the Emergency Department, ECG can come in handy as the first diagnosis of hyperkalemia before labs are drawn and reported. Early recognition of electrocardiographic (ECG) changes can prompt early correction and reduce mortality. We hereby, present a case of transient left bundle branch block in the setting of hyperkalemia secondary to statin-induced rhabdomyolysis.

Inhibiting ERK5 overcomes breast cancer resistance to anti-HER2 therapy by targeting the G1/S cell cycle transition.

Targeting the human epidermal growth factor receptor 2 (HER2) became a landmark in the treatment of HER2-driven breast cancer. Nonetheless, the clinical efficacy of anti-HER2 therapies can be short-lived and a significant proportion of patients ultimately develop metastatic disease and die. One striking consequence of oncogenic activation of HER2 in breast cancer cells is the constitutive activation of the extracellular-regulated protein kinase 5 (ERK5) through its hyperphosphorylation. In this study, we sought to decipher the significance of this unique molecular signature in promoting therapeutic resistance to anti-HER2 agents. We found that a small-molecule inhibitor of ERK5 suppressed the phosphorylation of the retinoblastoma protein (RB) in HER2 positive breast cancer cells. As a result, ERK5 inhibition enhanced the anti-proliferative activity of single-agent anti-HER2 therapy in resistant breast cancer cell lines by causing a G1 cell cycle arrest. Moreover, ERK5 knockdown restored the anti-tumor activity of the anti-HER2 agent lapatinib in human breast cancer xenografts. Taken together, these findings support the therapeutic potential of ERK5 inhibitors to improve the clinical benefit that patients receive from targeted HER2 therapies.

A Case of Atypical Hemolytic Uremic Syndrome in a Pregnant Patient.

Atypical hemolytic uremic syndrome (HUS) is a rare but severe form of thrombotic microangiopathies (TMAs) that affects both children and adults. The clinical presentation is usually nonspecific, including a broad spectrum of symptoms ranging from abdominal pain, confusion, diarrhea, fatigue, irritability, hypertension, and lethargy. We present a case of a 36-year-old woman with medical comorbidities of asthma and pulmonary embolism who presented to our hospital in the 36th week of her pregnancy for preterm premature rupture of the membranes. The postoperative course was complicated with a sudden onset drop in hemoglobin and acute onset thrombocytopenia. Complements levels were normal while ADAMTS 13 (von Willebrand factor-cleaving protease) activity was 81% which ruled out ADAMTS 13 deficiency. No significant clinical improvement was seen after five cycles of plasmapheresis. She was later started on Eculizumab biweekly with marked improvement in biochemical and clinical status. Prompt diagnosis and treatment of atypical HUS are crucial as the prognosis is poor if untreated. The diagnosis of atypical HUS can be challenging as the classic triad of microangiopathic hemolytic anemia, thrombocytopenia, and acute kidney injury can be seen in all thrombotic microangiopathies, thus careful clinical and laboratory assessment is required to establish the diagnosis. The new treatment modality, Eculizumab, the anti-complement monoclonal antibody, has become the first-line therapy for treating atypical HUS.

Post myocardial infarction left ventricular intramural dissecting hematoma: a case report describing a very rare complication.

BACKGROUND: Dissecting intramural hematoma is a rare complication of acute myocardial infarction (AMI) and has been associated with increased mortality. There has been paucity of literature to establish protocols and guidelines for management in such cases. CASE PRESENTATION: We hereby report the case of a 45-year-old male patient with left ventricular intramural dissecting hematoma (LV-IDH) who presented with chest pain and breathlessness and diagnosed as non-ST-elevation myocardial infarction (NSTEMI). Transthoracic echocardiography (TTE) was performed showing LV-IDH, confirmed with cardiac magnetic resonant imaging (cMRI). Selective coronary arteriography (CAG) was performed showing significant obstructive coronary artery disease (CAD). Further management with conservative approach involved discussion with patient, cardiothoracic surgeon and cardiology team including heart failure specialist and interventional cardiology. CONCLUSIONS: This case describes a rare complication of AMI and also focuses on utility of TTE and cMRI in the diagnosis of this rare complication. Both diagnosis and management are challenging and have to be individualized in similar cases. Multidisciplinary care coordination is important in management of patients with this diagnosis.

Biliary Sphincter of Oddi Dysfunction.

Sphincter of Oddi dysfunction (SOD) is a syndrome caused by either dyskinesia or stenosis of the sphincter of Oddi. It has been categorized into biliary and pancreatic SOD based on clinical features and laboratory findings. We present a case of a 51-year-old female (post-cholecystectomy) who presented with intermittent chronic right upper quadrant pain. Laboratory investigations showed persistently elevated liver function tests and a dilated common bile duct without the presence of any stones. Endoscopic retrograde cholangiopancreatography with manometry showed an elevated sphincter of Oddi pressure, thus confirming the diagnosis of SOD. She underwent endoscopic sphincterotomy and papillotomy with normalization of liver function tests and resolution of her chronic symptoms.

The extracellular-regulated protein kinase 5 (ERK5) enhances metastatic burden in triple-negative breast cancer through focal adhesion protein kinase (FAK)-mediated regulation of cell adhesion.

There is overwhelming clinical evidence that the extracellular-regulated protein kinase 5 (ERK5) is significantly dysregulated in human breast cancer. However, there is no definite understanding of the requirement of ERK5 in tumor growth and metastasis due to very limited characterization of the pathway in disease models. In this study, we report that a high level of ERK5 is a predictive marker of metastatic breast cancer. Mechanistically, our in vitro data revealed that ERK5 was critical for maintaining the invasive capability of triple-negative breast cancer (TNBC) cells through focal adhesion protein kinase (FAK) activation. Specifically, we found that phosphorylation of FAK at Tyr397 was controlled by a kinase-independent function of ERK5. Accordingly, silencing ERK5 in mammary tumor grafts impaired FAK phosphorylation at Tyr397 and suppressed TNBC cell metastasis to the lung without preventing tumor growth. Collectively, these results establish a functional relationship between ERK5 and FAK signaling in promoting malignancy. Thus, targeting the oncogenic ERK5-FAK axis represents a promising therapeutic strategy for breast cancer exhibiting aggressive clinical behavior.

An Unusual Case of Compartment Syndrome of the Upper Extremity Caused by an iPad.

Acute compartment syndrome develops when intracompartmental pressure increases either due to intrinsic or extrinsic causes. Increase in compartment pressure eventually can lead to impaired tissue perfusion followed by tissue death if no urgent intervention is performed. Patients with acute compartment syndrome usually present with pain out of proportion to apparent injury. It can cause rhabdomyolysis, myoglobinuria, and eventually acute renal failure. The definite treatment is fasciotomy in a timely manner. We here report a very interesting case of acute compartment syndrome in a young patient cause by pressure over his axilla by an iPad.

Digital Ischemia as an Initial Presentation in a COVID-19-Positive Patient Without Any Significant Respiratory Symptoms.

Coronavirus disease 2019 (COVID-19) is an evolving situation worldwide, which is associated with a broad range of symptoms from pneumonia/acute respiratory distress syndrome (ARDS) to multiorgan failure. So far, we have also encountered several patients with coagulopathy, including pulmonary embolism and deep vein thrombosis. A few cases of limb ischemia related to COVID-19 have been reported as well, but most of them involve critically ill patients. In this report, we discuss a case of COVID-19 in a patient who presented with right thumb ischemia without any significant respiratory symptoms.

COVID-19 and the Brain: Acute Encephalitis as a Clinical Manifestation.

Central nervous system (CNS) viral infections result in the clinical syndromes of aseptic meningitis or encephalitis. Although the primary target of coronavirus disease 2019 (COVID-19) is the respiratory system, it is increasingly being recognized as a neuropathogen. The hallmark clinical feature is altered mental status, ranging from mild confusion to deep coma. Most patients with encephalopathy or encephalitis are critically ill. We present a case of COVID-19-related encephalitis who presented with acute delirium and new-onset seizures. The patient responded well to treatment with intravenous immunoglobulins and rituximab.

Oxaliplatin-Induced Thrombocytopenia: A Case Report and Review of Pathophysiology of Various Speculative Mechanisms.

Oxaliplatin is one of the most common anti-neoplastic agents used in the treatment of small bowel adenocarcinoma. Peripheral neuropathy is one of the most common side effects of oxaliplatin. Oxaliplatin-induced thrombocytopenia is an extremely rare side effect and can result from various mechanisms. We present a case of a 66-year-old female who presented to the hospital for the ninth cycle of FOLFOX chemotherapy for her small bowel adenocarcinoma. The patient developed severe thrombocytopenia within 24 hours of administration of oxaliplatin. Physicians need to be aware of the sudden onset of severe thrombocytopenia associated with oxaliplatin use as early diagnosis and prompt treatment can prove lifesaving for these patients.

Acute Cytomegalovirus (CMV) Hepatitis in an Immunocompetent Adult.

BACKGROUND Cytomegalovirus (CMV) is a member of Herpesviridae family with its name derived from the fact that it causes enlargement of the infected cell resulting in the characteristic inclusion bodies seen on microscopy. CMV virus has an incubation period of about 4 to 6 weeks. Symptoms of CMV infection vary and depend on factors including the age and immune status of the patient. It usually presents as asymptomatic infection in immunocompetent individuals whereas severe disease is usually seen in immunocompromised patients. Here we present a case of an immunocompetent patient who presented with acute CMV hepatitis. CASE REPORT A 35-year-old male with no significant prior medical history who presented to the Emergency Department with a 2-week history of low-grade fever. Acute CMV infection was diagnosed by positive CMV antibody and polymerase chain reaction (PCR) testing. The patient was treated with valganciclovir that resulted in rapid improvement in clinical status as well as normalization of the liver enzymes. CONCLUSIONS This article presents a rare case of immunocompetent young male with acute CMV hepatitis who responded favorably to antiviral therapy.

A Microbiologist's Mexico Trip Ends with Multiple Tiny Ring-Like Pelvic Abscesses.

BACKGROUND Iliacus muscle abscess is a rare condition that frequently presents with nonspecific clinical symptoms. Abscesses in the iliacus muscle can arise from contiguous spread from adjacent structures or from distant sites via hematogenous or lymphatic routes. CASE REPORT We report a case of iliacus muscle abscess in a 22-year-old female microbiologist who presented to the emergency department with severe back pain and lower-extremity weakness after returning from a trip to Mexico. She was found to have urinary tract infection due to Salmonella. The patient was found to have left iliacus muscle abscess and septic arthritis of the sacroiliac joint. She was initially treated with piperacillin-tazobactam, vancomycin, and metronidazole, which were later switched to intravenous ceftriaxone and oral levofloxacin. She was successfully treated with antibiotics, with a complete resolution of the multiple tiny abscesses. CONCLUSIONS Iliacus muscle abscess presents with nonspecific symptoms that can mimic neurologic diseases such as spinal cord compression. A high index of suspicion is required to make an early diagnosis and initiate prompt treatment with antibiotics and abscess drainage, if accessible. A detailed history is essential to assess risk factors and establish likely causative organisms. Delay in treatment can lead to an increase in morbidity and mortality. Long-term follow-up is crucial, as the incidence of relapse is high.

A Rare Presentation of Angina and Arrhythmia in Absent Left Main Coronary Artery.

Coronary artery anomalies (CAAs) are congenital disorders with multiple variations in the number, shape, and location of the Ostia of the coronary arterial system. The congenitally absent left main coronary artery (LMCA) is a rare anomaly that can present with benign or fatal complications ahead in life. Diagnosis and management of CAAs are sometimes challenging in low-risk patients. We present a unique case report of a 69-year-old Hispanic female who presented to the hospital with exercise-induced arrhythmia and angina symptoms. The patient complained of several episodes of chest pain, dizziness, and palpitations for a duration of two months. Electrocardiogram (EKG) and nuclear stress tests were equivocal. The angiogram revealed the separate origin of the left anterior descending artery (LAD) and left circumflex coronary artery (LCX) from the left coronary sinus. This anomaly should be considered in differentials when evaluating patients with angina symptoms. Congenital absence of LMCA is a rare condition that remains asymptomatic in the majority of the cases. It can present with exertional chest pain, palpitations, syncope, and sudden cardiac death (SCD). Occurrences of angina and arrhythmia should be carefully evaluated, and symptoms should be followed up closely. A coronary angiogram and electrophysiological testing can assist in the diagnosis.