Arunabh Sekhri

Warfarin use and the risk of valvular calcification.

Summary.  Background: Warfarin affects the synthesis and function of the matrix Gla‐protein, a vitamin K‐dependent protein, which is a potent inhibitor of tissue calcification. Objectives: To investigate the incidence of mitral valve calcium (MVC), mitral annular calcium (MAC) and aortic valve calcium (AVC) in patients with non‐valvular atrial fibrillation (AF) treated with warfarin vs. no warfarin. Patients and methods: Of 1155 patients, mean age 74 years, with AF, 725 (63%) were treated with warfarin and 430 (37%) without warfarin. The incidence of MVC, MAC and AVC was investigated in these 1155 patients with two‐dimensional echocardiograms. Unadjusted logistic regression analysis was conducted to examine the association between the use of warfarin and the incidence of MVC, MAC or AVC. Logistic regression analyses were also conducted to investigate whether the relationship stands after adjustment for confounding risk factors such as age, sex, race, ejection fraction, smoking, hypertension, diabetes, dyslipidemia, coronary artery disease (CAD), glomerular filtration rate, calcium, phosphorus, calcium‐phosphorus product, alkaline phosphatase, use of aspirin, beta blockers, angiotensin‐converting enzyme inhibitors or angiotensin receptor blockers, and statins. Results: There was a significant association between the use of warfarin and the risk of calcification [unadjusted odds ratio = 1.71, 95% CI = (1.34–2.18)]. The association still stands after adjustment for confounding risk factors. MVC, MAC or AVC was present in 473 of 725 patients (65%) on warfarin vs. 225 of 430 patients (52%) not on warfarin (P < 0.0001). Whether this is a causal relationship remains unknown. Conclusions: Use of warfarin in patients with AF is associated with an increased prevalence of MVC, MAC or AVC.

Selective inhibitors of nuclear export (SINE)- a novel class of anti-cancer agents

Dysregulation of the nucleo-cytoplasmic transport of proteins plays an important role in carcinogenesis. The nuclear export of proteins depends on the activity of transport proteins, exportins. Exportins belong to the karyopherin β superfamily. Exportin-1 (XPO1), also known as chromosomal region maintenance 1 (CRM1), mediates transport of around 220 proteins. In this review, we summarized the development of a new class of antitumor drugs, collectively known as selective inhibitors of nuclear export (SINE). KPT-330 (selinexor) as an oral agent is showing activities in early clinical trials in both solid tumors and hematological malignancies.

Association of warfarin use with valvular and vascular calcification: a review.

Vitamin K is required for the activity of various biologically active proteins in our body. Apart from clotting factors, vitamin K–dependent proteins include regulatory proteins like protein C, protein S, protein Z, osteocalcin, growth arrest‐specific gene 6 protein, and matrix Gla protein. Glutamic acid residues in matrix Gla protein are γ‐carboxylated by vitamin K–dependent γ‐carboxylase, which enables it to inhibit calcification. Warfarin, being a vitamin K antagonist, inhibits this process, and has been associated with calcification in various animal and human studies. Though no specific guidelines are currently available to prevent or treat this less‐recognized side effect, discontinuing warfarin and using an alternative anticoagulant seems to be a reasonable option. Newer anticoagulants such as dabigatran and rivaroxaban offer promise as future therapeutic options in such cases. Drugs including statins, alendronate, osteoprotegerin, and vitamin K are currently under study as therapies to prevent or treat warfarin‐associated calcification. Copyright

Interstitial lung disease associated with azacitidine use: a case report.

Azacitidine is a pyrimidine nucleoside analog licensed for treatment of adult patients with myelodysplastic syndrome. Azacitidine acts as an inducer of cell differentiation by causing demethylation and re-expression of genes silenced by hypermethylation. We report a 56-year-old man with myelodysplastic syndrome who developed interstitial lung disease after azacitidine therapy. Open lung biopsy revealed a nonresolving organizing pneumonia pattern and bronchocentric granulomatous pattern suggestive of drug-induced lung injury. Treatment with steroids and discontinuation of azacitidine led to resolution of interstitial lung disease. The Naranjo adverse drug reaction probability scale score indicated that the association between azacitidine and interstitial lung disease was probable. Interstitial lung disease is a serious but uncommon side effect of this relatively safe drug. The mechanism underlying this is still unclear. The patient was subsequently treated with decitabine with no recurrence of interstitial lung disease.

Mobile physician reporting of clinically significant events-a novel way to improve handoff communication and supervision of resident on call activities.

Objectives Reporting of clinically significant events represents an important mechanism by which patient safety problems may be identified and corrected. However, time pressure and cumbersome report entry procedures have discouraged the full participation of physicians. To improve the process, our internal medicine training program developed an easy-to-use mobile platform that combines the reporting process with patient sign-out. Methods Between August 25, 2011, and January 25, 2012, our trainees entered clinically significant events into i-touch/i-phone/i-pad based devices functioning in wireless-synchrony with our desktop application. Events were collected into daily reports that were sent from the handoff system to program leaders and attending physicians to plan for rounds and to correct safety problems. Results Using the mobile module, residents entered 31 reportable events per month versus the 12 events per month that were reported via desktop during a previous 6-month study period. Conclusions Advances in information technology now permit clinically significant events that take place during “off hours” to be identified and reported (via handoff) to next providers and to supervisors via collated reports. This information permits hospital leaders to correct safety issues quickly and effectively, while attending physicians are able to use information gleaned from the reports to optimize rounding plans and to provide additional oversight of trainee on call patient management decisions.

Warfarin use and prevalence of coronary artery calcification assessed by multislice computed tomography.

Warfarin inhibits the synthesis and function of matrix Gla protein, a vitamin K–dependent protein, which is a potent inhibitor of tissue calcification. We had earlier reported the association of warfarin use with valvular calcification in patients with nonvalvular atrial fibrillation. The aim of our present study was to investigate the association of warfarin use with the presence and severity of coronary artery calcification. A total of 233 patients underwent computed tomography scan (CT) at our institution for the assessment of coronary artery calcium score (CACS). Of 233 patients, the mean age was 63 years, 28 patients (12%) were treated with warfarin, and 205 patients (88%) were not on warfarin. Based on their total CACS, the patients were subsequently stratified into 59 with no coronary calcium (CACS = 0), 63 with low CACS (1–100), 49 with moderate CACS (101–400), 33 with severe CACS (410–1000), and 29 with very severe CACS (>1000). The &khgr;2 test and Student t-test were used for the comparison of categorical and continuous variables, respectively, between warfarin users and nonusers. Using the variables age, gender, race, smoking, hypertension, diabetes, dyslipidemia, glomerular filtration rate, calcium–phosphorus product, alkaline phosphatase, use of aspirin, beta blockers, angiotensin-converting enzyme inhibitors or angiotensin receptor blockers, and statins, stepwise logistic regression analysis did not show any association of coronary calcification with use of warfarin. In our study, warfarin use was not associated with a higher prevalence or severity of CACS assessed by coronary computed tomography.

Very late relapse of chronic myelogenous leukemia after allogeneic bone marrow transplantation

Allogeneic stem cell transplantation is considered to be a curative treatment modality in patients with chronic myelogenous leukemia. However patients are at risk for relapse years after transplantation. Currently we present two patients who relapsed 16 and 24 years after allogeneic bone marrow transplantation, respectively. These patients emphasize the need for long term follow-up of such patients.

The Conundrum of "Warfarin Hypersensitivity": Prolonged Partial Thromboplastin Time From Factor IX Propeptide Mutation.

Carboxylation of glutamic acid residues of vitamin K dependent clotting factors (II, VII, IX, and X) is essential to their biological functioning. Binding of these factors to &ggr;-glutamyl carboxylase enzyme for carboxylation reaction is mediated by wild-type propeptide, a small sequence of amino acids that precede the actual polypeptide. Missense mutations at certain residue severely decrease the affinity of mutated propeptide for the enzyme. Such mutations are reported to occur at codon-10 of factor IX propeptide, a clinically silent metabolic event in normal conditions. However in the presence of warfarin, such mutations and resultant decrease affinity of factor IX propeptide for the enzyme that causes severe selective decrease in factor IX activity. This can potentially leads to life-threatening bleeding complications and known as one of the causes of warfarin hypersensitivity. It is imperative to recognize such cases early on to avoid additional warfarin therapy. Recurrent bleeding episodes, subtherapeutic to therapeutic range international normalized ratio values with relatively prolong partial thromboplastin time should raise the suspicion of underlying factor IX propeptide mutations.

Multiple myeloma with leptomeningeal involvement and positive CSF

A 50-year-old female with multiple myeloma was initially treated with lenalidomide/bortezomib/dexamethasone. She had progression of disease after three cycles. She was then treated with DB-PACE (dexamethasone, bortezomib, cisplatin, doxorubicin, cyclophosphamide, etoposide) ×3 cycles.