Terbinafine induced fulminant hepatic failure and patient death

A 72 year-old-patient without known past medical history presented to the hospital with worsening cough, dyspnea on exertion, decreased appetite, weight loss for two months. Prior to admission, he was treated with a 10- day course of levofloxacin and prednisone as a case of bronchitis with minimal improvement. Then he started to develop red urine with marked changes in mental status. On physical examination, the patient had notifiable scleral icterus, confusion and abdominal tenderness in the right upper quadrant. On admission his labs were significant for alkaline phosphatase 541, aspartate transaminase 557, alanine transaminase 94, total bilirubin 8.6, lactate 11.7. CT scan of abdomen showed hepatosplenomegaly, mild ascites and trace bilateral pleural effusion. Work up with Viral hepatitis serology, cryptococcal antigen, histoplasma antigen, respiratory virus panel, Epstein Barr virus tests were negative. Anti-nuclear antibodies (ANA) and anti-mitochondrial antibody were also negative. Blood level of amylase, lipase, acetaminophen and alcohol were negative at admission too. The patient was started initially on broad spectrum antibiotics, N-acetyl cysteine empirically and aggressive intravenous fluid hydration. Patient condition rapidly worsened and he developed profound shock requiring mechanical ventilation and started on stress dose steroid and pressor support. Upon further investigation, patient was noted to take terbinafine for toe onychomycosis (day 112). Ferritin level was elevated to 1596 with 93% iron saturation. Ceruloplasmin level was normal. Patient was not a transplant candidate due to multiple organ failure. As per family request, patient was palliatively extubated and died. Terbinafine is a fungicidal drug with activity against dermatophytes including Epidermophyton flccosum and trichophyton rubrum. It works by inhibition of squalene epoxidase with a resultant accumulation of squalene in the fungal cell and killing it as a result. Commonly used orally to treat onychomycosis and other fingernails and toenails infections. Shortly after its introduction to the market, DILI had been reported with elevation with serum aminotransferases elevation that was usually self-limited. Usually presents within first 6 weeks of therapy with either hepatocellular or cholestatic initially with sings of hypersensitivity. Mechanism of injury entails hypersensitivity reaction, though the full pathogenesis was not elucidated yet, but genetic polymorphism is implicated in the variable presentation especially among HLA-A 33:01 allele carriers. Terbinafine DILI resolves usually within 6 months of stopping the medication but can lead to death or need liver transplantation in some cases

COPD exacerbation induced Takotsubo Cardiomyopathy

Introduction: Takotsubo cardiomyopathy or stress cardiomyopathy is a syndrome of transient left ventricular (LV) dysfunction mimicking myocardial infarction, but lacking obstruction of coronary artery disease (CAD) or acute plaque rupture. A characteristic differentiation from CAD is that regional motional abnormality extends beyond a territory perfused with a single epicardial coronary artery. Clinically, it is characterized by apical ballooning of the LV due to due to depression of mid and apical segments, with hyperkinesis of cardiac basal walls. Women are affected more than men, predominantly in the postmenopausal age. Case Report: A 54-year-old Caucasian female with a history of COPD, hypertension, uncontrolled diabetes mellitus, hyperlipidemia, depression and ongoing tobacco use presented with complaints of worsening shortness of breath two days prior to admission. She denied chest pain, worsened cough, palpitations, nausea or vomiting. On examination, she was in distress and anxious, with labored breathing. Upon examining the chest, decreased air entry was present in both lung fields with bibasilar wheezing. Initial lab tests showed mild respiratory acidosis, with pH of 7.24, pCO2 of 47.4 and pO2 of 65. Troponins on the day of admission was Soon after admission, she started complaining of severe right neck pain. Repeat EKG revealed localized lateral J point, anteroseptal q waves and 4mm ST-segment elevation in leads V3 and V4 reciprocal changes and without chest pain. Repeat troponins were slightly elevated to 0.42 ng/ml and CK-MB was elevated to 20.2 ng/ml. A transthoracic echocardiogram showed regional abnormalities in left ventricle with the apex, mid to distal septum and the anterior part of septum was akinetic. Discussion: Takotsubo cardiomyopathy presents in 1 to 2 percent of troponin-positive acute coronary syndrome (ACS) with various clinical manifestations and various outcomes. Some patients have favorable outcomes based on their clinical performance and extent of cardiac muscle involvement. As in the case we presented, this syndrome can be entirely idiopathic, without a definitive underlying cause. Supportive management while hospitalized and early identification of complications improve the prognosis

Role of ribosomal RNA released from red cells in blood coagulation in zebrafish and humans

This article identifies that an rRNA released in hemolysis activates clotting in human and zebrafish plasma. Furthermore, it shows that fish Hgfac plays a role in rRNA-mediated activation of coagulation

Role of MicroRNAs and Their Downstream Targets in Zebrafish Thrombopoiesis

Previous studies have shown that human platelets and megakaryocytes carry microRNAs suggesting their role in platelet function and megakaryocyte development, respectively. However, there is limited information on microRNAs' role in zebrafish thrombopoiesis. Zebrafish thrombocytes could be used as a model to study their role in megakaryocyte maturation and platelet function because thrombocytes have both megakaryocyte features and platelet properties. In our laboratory, I identified 15 microRNAs in thrombocytes using single-cell RNA sequencing. Knockdown of three microRNAs, mir-7148, let-7b, and mir-223, by the piggyback method in zebrafish led to an increase in the percentage of thrombocytes. Functional thrombocyte analysis using plate tilt assay showed no modulatory effect of the three microRNAs on thrombocyte aggregation/agglutination. I then verified these findings in zebrafish larvae after the knockdown of the above microRNAs followed by an arterial laser thrombosis assay. I concluded mir-7148, let-7b, and mir-223 are repressors for thrombocyte production. Furthermore, I explored let-7b downstream genes in thrombocytes detected by RNA-seq analysis and chose 14 targets based on their role in cell differentiation (rorca, tgif1, rfx1a, deaf1, zbtb18, mafba, cebpa, spi1a, spi1b, fhl3b, ikzf1, irf5, irf8, and lbx1b) that are transcriptional regulators. The qRT-PCR analysis of expression levels the above genes following let-7b knockdown showed significant changes in the expression of 13 targets. I then studied the effect of the 14 targets on thrombocytes production and identified 5 genes (irf5, tgif1, irf8, cebpa, and rorca) that showed thrombocytosis and one gene ikzf1 that showed thrombocytopenia. Furthermore, I tested whether mir-223 regulates any of the above 13 transcription factors after mir-223 knockdown using qRT-PCR. Six of the 13 genes showed similar gene expression as observed with let-7b knockdown and 7 genes showed opposing results. Thus, our results suggested a possible regulatory network in common with both let-7b and mir-223. I also identified that tgif1, cebpa, ikzf1, irf5, irf8, and ikzf1 play a role in thrombopoiesis. Since the ikzf1 gene showed a opposite expression profiles following let-7b and mir-223 knockdowns (decreased and increased expression, respectively) and knockdown of ikzf1 resulted in thrombocytopenia I confirmed a definitive role for ikzf1 using an ikzf1 mutant obtained from the Zebrafish International Resource Center (ZIRC). The arterial laser thrombosis assay of ikzf1 mutant progeny confirmed our piggyback hybrid knockdown results. Taken together, these studies shed light on understanding the role and the regulatory effects of zebrafish microRNA on thrombopoiesis and identified novel downstream target transcription factors for let-7b and mir-223

Splenectomy in zebrafish: a new model for immune thrombocytopenia

In humans, splenectomy is performed to treat many clinical disorders, including immune thrombocytopenia. However, the incidence of splenectomies for immune thrombocytopenia as a therapeutic has significantly declined over the past decade due to the availability of new therapies. Infection and sepsis as a result of splenectomies are well documented, but other long-term effects are not well characterized. Evidence suggests that persons who have had a prior splenectomy may be at an increased risk of vascular conditions. Also, elevated levels of cell-derived microparticles appear to contribute to an increased risk of thrombosis and cardiovascular disease. However, in vivo studies on the increased levels of microparticles following splenectomy are limited. In order to understand the effects of splenectomies, we developed a protocol for splenectomy in adult zebrafish. After anesthesia, the spleen was removed under a stereomicroscope after making an incision on the ventral side of the fish. The spleen was removed by pulling with forceps. The incision was closed by Vetbond tissue glue. Blood collected from both splenectomized zebrafish and those that underwent sham surgeries was immunolabeled with polyclonal antisera against αIIb, followed by flow cytometry. We observed elevated levels of thrombocytes and their microparticles in splenectomized zebrafish. Finally, by injecting αIIb antibody intravenously into zebrafish, we found the thrombocyte counts decreased, suggesting the fish developed immune thrombocytopenia like conditions, which were then reversed by splenectomy. In summary, the model developed here should be useful to study molecular changes due to splenectomy. Also, the zebrafish will be useful in modeling treatment of immune thrombocytopenia like conditions

Role of microRNAs and their downstream target transcription factors in zebrafish thrombopoiesis

Abstract Previous studies have shown that human platelets and megakaryocytes carry microRNAs suggesting their role in platelet function and megakaryocyte development, respectively. However, a comprehensive study on the microRNAs and their targets has not been undertaken. Zebrafish thrombocytes could be used as a model to study their role in megakaryocyte maturation and platelet function because thrombocytes have both megakaryocyte features and platelet properties. In our laboratory, we identified 15 microRNAs in thrombocytes using single-cell RNA sequencing. We knocked down each of these 15 microRNAs by the piggyback method and found knockdown of three microRNAs, mir-7148, let-7b, and mir-223 in adult zebrafish led to an increase in the percentage of thrombocytes. Functional thrombocyte analysis using plate tilt assay showed no modulatory effect of the three microRNAs on thrombocyte aggregation/agglutination. We also found enhanced thrombosis using arterial laser thrombosis assay in a group of zebrafish larvae after mir-7148, let-7b, and mir-223 knockdowns. These results suggested mir-7148, let-7b, and mir-223 are repressors for thrombocyte production. We then explored miRWalk database for let-7b downstream targets and then selected those that are expressed in thrombocytes, and from this list based on their role in differentiation selected 14 genes, rorca, tgif1, rfx1a, deaf1, zbtb18, mafba, cebpa, spi1a, spi1b, fhl3b, ikzf1, irf5, irf8, and lbx1b that encode transcriptional regulators. The qRT-PCR analysis of expression levels of the above genes following let-7b knockdown showed changes in the expression of 13 targets. We then studied the effect of the 13 targets on thrombocyte production and identified 5 genes, irf5, tgif1, irf8, cebpa, and rorca that showed thrombocytosis and one gene, ikzf1 that showed thrombocytopenia. Furthermore, we tested whether mir-223 regulates any of the above 13 transcription factors after mir-223 knockdown using qRT-PCR. Six of the 13 genes showed similar gene expression as observed with let-7b knockdown and 7 genes showed opposing results. Thus, our results suggested a possible regulatory network in common with both let-7b and mir-223. We also identified that tgif1, cebpa, ikzf1, irf5, irf8, and ikzf1 play a role in thrombopoiesis. Since the ikzf1 gene showed a differential expression profile in let-7b and mir-223 knockdowns but resulted in thrombocytopenia in ikzf1 knockdown in both adults and larvae we also studied an ikzf1 mutant and showed the mutant had thrombocytopenia. Taken together, these studies showed that thrombopoiesis is controlled by a network of transcription regulators that are regulated by multiple microRNAs in both positive and negative manner resulting in overall inhibition of thrombopoiesis