Troponin in hematologic oncology

Loeffler's Endocarditis and Hypereosinophilic Syndrome

Loeffler's endocarditis and hypereosinophilic syndromes are a unique group of infiltrative disorders characterized by hypereosinophilia, inflammatory thrombotic, and ultimately, fibrotic involvement of the heart leading to multiple complications including valve involvement, thromboembolic phenomena, heart failure. Clinical recognition, comprehensive laboratory and multimodality imaging diagnostic workup, and early initiation of treatment have been shown to slow down the progression and promote remission. This review addresses a detailed analysis of Loeffler's endocarditis and hypereosinophilic syndromes.

Missed opportunity for anticoagulation in a patient with AL cardiac amyloidosis and rapidly progressive heart failure

A previously healthy 65-year-old woman presented with progressive symptoms of heart failure. Low-voltage ECG and findings on echocardiography were concerning for infiltrative cardiomyopathy. Cardiac MRI showed biventricular late gadolinium enhancement, and endomyocardial biopsy confirmed monoclonal immunoglobulin light-chain (AL) amyloidosis. Bortezomib-based chemotherapy was initiated, but the patient continued to clinically deteriorate. She required hospital readmission after resuscitated out-of-hospital cardiac arrest attributed to progressive conduction disease, and a permanent pacemaker was implanted. Chest CT angiography showed a small subsegmental pulmonary embolism (PE), but anticoagulation was withheld as her lower extremity Doppler was negative. One month later, another pulseless electrical arrest occurred, due to massive PE. Thereafter, she had refractory class IV congestive heart failure with severe right ventricular dysfunction, and was deemed unsuitable for stem-cell or heart transplantation. This case highlights the predilection for thromboembolism in AL cardiac amyloidosis.

Hypereosinophilic syndrome associated with ulcerative colitis presenting with recurrent Loeffler's endocarditis and left ventricular thrombus treated successfully with immune suppressive therapy and anticoagulation

We reported a case of a 28-year-old Caucasian woman with hypereosinophilic syndrome (HES) associated with ulcerative colitis who presented on separate occasions with Loeffler's endocarditis. She was admitted in 2008 with fever, headache, confusion and visual loss. Diagnostic workup uncovered an eosinophilia of 3.1×10⁹/L and major ECG abnormalities. Subsequent echocardiography revealed left ventricular wall motion abnormalities with mural thrombus. MRI brain scan showed multiple white matter lesions consistent with acute infarcts. She recovered rapidly with corticosteroids and anticoagulation. Four years later she re-presented with headache, fatigue and an eosinophilia of 13.4×10⁹/L. This occurred 3 months after cessation of immunosuppression and within 12 months of total colectomy for fulminant ulcerative colitis. Echocardiography was suggestive of hypereosinophilic endomyocardial fibrosis with left ventricular thrombus. Anticoagulation and corticosteroids were resumed with good effect. This report highlights the findings, treatment and outcome of ulcerative colitis-associated HES manifesting as recurrent Loeffler's endocarditis.

Current applications of cardiac troponin T for the diagnosis of myocardial damage

Biochemical markers of myocardial injury play an important role in the diagnosis of cardiovascular diseases. Measurement of cardiac biomarkers is one of the most important diagnostic tests in acute myocardial infarction (AMI), heart failure, and other cardiovascular disorders. Recently, the European Society of Cardiology, the American College of Cardiology Foundation, the American Heart Association, and the World Heart Federation have published a consensus definition of AMI that includes a detailed guideline for the assessment of biochemical markers in suspected disease. The cardiac troponins (cTI and cTnT) were recommended as preferred markers of myocardial necrosis in this setting. Herein, we review cardiac troponin biochemistry, the performance characteristics of cTnT assays, and optimal utilization of troponin in patients with proven or possible cardiovascular disease. We also discuss the use of troponin tests, with emphasis on cTnT, in different clinical situations in which its levels may be elevated.

Advances in diagnosis and treatment of eosinophilia

PURPOSE OF REVIEW

Hypereosinophilic syndromes (HESs) are disorders characterized by sustained blood or tissue hypereosinophilia or both with subsequent damage to various organs due to eosinophilic infiltration and release of mediators. HES are now recognized to include varied eosinophilic disorders for some of which there are recent insights into their pathogenesis and targeted treatment.

RECENT FINDINGS

Studies have helped delineate two subtypes of HES: the myeloproliferative variants of HES and the lymphocytic variants of HES. Many, but not all, myeloproliferative-HES patients have interstitial deletions on chromosome 4q12 that lead to fusion of the FIP1-like 1 and platelet-derived growth factor receptor alpha genes, with the fusion product encoding a protein that has constitutive tyrosine kinase activity. Lymphocytic-HES is a primary lymphoid disorder characterized by nonmalignant expansion of a T-cell population able to produce eosinophilopoietic cytokines, with the T-cell population being identified by flow cytometry or reverse transcriptase-PCR for T-cell receptor usage or both. Other HES subtypes are of uncertain causes and are included in recent diagnostic algorithms for the spectrum of HES.

SUMMARY

The contemporary definition of the hypereosinophilic syndromes encompasses a range of eosinophilic disorders characterized by chronic blood hypereosinophilia often with eosinophil-mediated damage to various organs.