Diagnosing Cardiac Amyloidosis: From Heart Failure to Electrical Storm.

Cardiac amyloidosis is a condition when amyloid fibers are deposited in the extracellular space of the heart causing tachyarrhythmias, heart failure, or sudden cardiac death. We present a 71-year-old woman presenting with dyspnea on admission. Echocardiogram revealed diastolic heart failure and left ventricular hypertrophy with strain pattern concerning for an infiltrative process. She was discharged with diuretic therapy and scheduled for a cardiac magnetic resonance imaging. One week after discharge, she was readmitted with progressive shortness of breath and syncope. She was found to be in shock and had multiple episodes of cardiac arrest with both ventricular tachycardia and pulseless electrical activity. She developed electrical storm and eventually passed within 24 hours. Autopsy revealed gross cardiomegaly and left ventricular hypertrophy with Congo red staining revealing amyloid fibrils with apple-green birefringence. This case demonstrates the rapid progression of cardiac amyloidosis from acute-onset diastolic heart failure to uncontrollable ventricular tachycardia, and eventually death. We review the literature regarding multiple diagnostic modalities that facilitate the confirmation of cardiac amyloidosis.

A practical approach to diagnose soft tissue myeloid sarcoma preceding or coinciding with acute myeloid leukemia.

Myeloid sarcoma involving soft tissue is rare and may present a pathologic diagnostic challenge, particularly when it precedes or coincides with hematological malignancies. Furthermore, it may mimic non-Hodgkin lymphoma, poorly differentiated carcinoma, melanoma, or round blue cell tumors, which is a potential diagnostic pitfall. In addition to a retrospective review of myeloid sarcoma (MS) cases seen at our institution, we describe differential diagnoses, diagnostic pitfalls, and practical approaches to diagnosing soft tissue MS preceding or coinciding with acute myeloid leukemia. Our institutional retrospective review (1999-2011) of MSs identified 12 cases of MS in which there was no known blood or bone marrow involvement at diagnosis. A panel of immunohistochemical stains and/or flow cytometry was reviewed; marker selection was subject to the pathologist's discretion. These tumors were consistently positive for CD117 (9/9), CD43 (7/7), myeloperoxidase (8/10), CD68 (4/5), and CD34 (5/9) by flow cytometry and/or immunohistochemistry. We also described a referral case, which had classic MS morphology and a myelomonocytic immunophenotype including positivity for CD45, lysozyme, and CD117 with supporting molecular information. Based on our institution's experience and review of the literature, we recommend that when the index of suspicion for MS is high, an immunohistochemical stain and/or flow cytometry panel should include CD43, lysozyme, CD117, CD68, CD33, Human Leukocyte Antigen DR (HLA-DR), and myeloperoxidase, in addition to thorough review of the patient's history, cytogenetic studies, and proper discussion with the clinician.

Osteolipoma of the parapharyngeal space mimicking liposarcoma: a case report.

BACKGROUND: Lipomas are the most common benign neoplasm of the head and neck. However, osteolipomas, a rare variant of lipoma, are uncommon in this location. When they occur, variations in location and radiographic presentation may obscure the diagnosis. METHODS AND RESULTS: A 68-year-old man presented with left jaw pain and numbness in the maxillary (V-1) distribution. A CT angiography of the neck revealed a possible liposarcoma. Embolization of the mass was determined to be unfeasible. Consequently, surgical resection was performed revealing a benign osteolipoma. CONCLUSION: We report a rare case of osteolipoma of the parapharyngeal space. Clinicians should be aware that the clinical and radiological features of patients with head and neck osteolipomas may mimic malignant neoplasms. When given deserved consideration, inappropriate treatment of an otherwise benign lesion may be avoided.

Hematopoietic stem cell origin of human fibroblasts: cell culture studies of female recipients of gender-mismatched stem cell transplantation and patients with chronic myelogenous leukemia.

OBJECTIVE: Our series of studies using transplantation of single hematopoietic stem cells (HSCs) demonstrated that mouse fibroblasts/myofibroblasts are derived from HSCs. In order to determine the origin of human fibroblasts, we established a method for culturing fibroblasts from human peripheral blood (PB) mononuclear cells and studied fibroblasts from gender-mismatched HSC transplant recipients and patients with untreated Philadelphia chromosome-positive chronic myelogenous leukemia (CML). MATERIALS AND METHODS: We cultured PB cells from three female subjects who showed near-complete hematopoietic reconstitution from transplantation of granulocyte-colony stimulating factor-mobilized male PB cells and examined the resulting fibroblasts using fluorescent in situ hybridization for Y chromosome. Because the mobilized PB cells may contain mesenchymal stem cells, we could not determine the HSC or mesenchymal stem cell origin of the fibroblasts seen in culture. To further document the HSC origin of human fibroblasts, we next examined fibroblasts from two patients with untreated CML, a known clonal disorder of HSCs. RESULTS: All cultured fibroblasts from female recipients of male cells showed the presence of Y chromosome, indicating the donor origin of fibroblasts. Cultured fibroblasts from the CML patients revealed the presence of BCR-ABL translocation. This demonstration provided strong evidence for the HSC origin of human fibroblasts because CML is a clonal disorder of the HSC. CONCLUSIONS: These studies strongly suggest that human fibroblasts are derived from HSCs. In addition, the results suggest that fibrosis seen in patients with CML may be a part of the clonal process.