Differentiating fulminant EBV infection complicated by HLH from Lymphoma: report of a case and a brief literature review.

Epstein-Barr virus (EBV) infection may present with fulminant constitutional symptoms, cytopenia(s), and systemic lymphadenopathy, raising clinical suspicion for lymphoma and prompting lymph node and bone marrow biopsies. At the microscopic level, the histopathologic findings in cases of acute EBV lymphadenitis may mimic certain lymphoid neoplasms, creating a range of differential diagnoses and diagnostic pitfalls.We present a case of fulminant EBV infection in an adolescent whose clinical and radiographic findings led to lymph node and bone marrow biopsies to rule out lymphoma. One week after being diagnosed with acute EBV infection (infectious mononucleosis), a 17-year-old Caucasian male presented with worsening symptoms including persistent fever, progressive, painful lymphadenopathy, and splenomegaly. A peripheral blood smear showed lymphocytosis with many reactive lymphocytes, anemia, and thrombocytopenia. Laboratory studies showed elevated ferritin, triglycerides, and soluble IL-2/CD25. A cervical lymph node biopsy demonstrated an EBV-positive, reactive B-immunoblast proliferation with large atypical lymphoid cells mimicking Reed-Sternberg cells of Hodgkin lymphoma, in addition to patchy vasculitis, coagulative necrosis, and prominent hemophagocytic activity. Bilateral bone marrow biopsies showed a hypercellular marrow with patchy infiltrates of similar EBV-positive, large atypical lymphoid cells, as well as prominent hemophagocytic activity. The diagnosis of acute EBV associated lymphoproliferation with concurrent hemophagocytic lymphohistiocytosis (HLH) was rendered.Recognition of common and uncommon clinical presentations of acute EBV infection is essential, particularly when histopathologic findings raise suspicion for a possible hematolymphoid neoplasm. Both the lymph node architectural and viral cytopathic changes observed in EBV lymphadenitis exhibit significant morphologic overlap with classic Hodgkin lymphoma (cHL) and several other lymphomas, including anaplastic large cell lymphoma, diffuse large B cell lymphoma, and angioimmunoblastic T cell lymphoma. Recognition of immunohistochemical staining patterns in EBV lymphadenitis is critical to avoid misdiagnosis. Conversely, bona fide lymphoma, particularly cHL, can masquerade as EBV infection. We provide a concise discussion and tables of the histopathologic differential diagnosis of EBV lymphadenitis, including cHL and other lymphomas. Pathologists should include acute EBV infection within the differential diagnosis when confronted with clinical and pathologic findings concerning for lymphoma, particularly in adolescents and young adults.

Formalin pre-fixation improves autopsy histology.

Microscopic findings in key tissues are often critical to determine the cause of death in medical autopsies. The overall quality of histologic sections depends on numerous pre-analytic factors, among which are tissue section size and thickness. We designed a prospective quality improvement study to determine whether a simple intervention of formalin pre-fixation of myocardium, liver, and kidney tissues could improve the ease of cutting and quality of autopsy histologic sections as assessed by histotechnicians and pathologists. Of 46 autopsies included in the study, 21 were randomly assigned to formalin pre-fixation, and 25 underwent routine sectioning without formalin pre-fixation. A significant improvement in overall quality score by histotechnicians was detected in the sections from pre-fixed autopsy tissues compared to the control group (p=0.0327). There was no significant difference in quality score between the two groups as assessed by pathologists. Our autopsy quality improvement study demonstrates that a simple, low-cost intervention of formalin pre-fixation of fresh autopsy tissues for 90 minutes could significantly improve the overall quality of sections submitted for histologic processing.

An unexpected paradox: wall shear stress in the aorta is less in patients with severe atherosclerosis regardless of obesity.

BACKGROUND: Obesity is a widespread condition that is more prevalent in Western countries compared to others. Aortic atherosclerosis (AA) is a condition that frequently has been associated with obesity. An obesity paradox, where morbidly obese decedents had either no or minimal AA compared to nonobese decedents, recently has been described by some of us. The explanation for this almost counterintuitive paradox has yet to be determined, but a number of hypotheses were advanced, including hemodynamic factors producing aortic wall shear stress (WSS). The purpose of the present study was to determine if there was a relationship between AA and WSS, as determined by postmortem measurement of aortic wall diameters. METHODS: Circumferences of the aorta at the levels of the ascending, thoracic and abdominal aorta were measured in 274 consecutive autopsies over 2-year period of time. AA was assessed using a previously described grading scale as either mild or severe. Circumferences were mathematically converted to diameters and WSS was calculated using the Hagen-Poiseuille formula. Two different methods to estimate cardiac output were used, both based on literature methods, one of which was body mass index (BMI) dependent, and the other BMI independent. Univariate and multivariable analyses of the relationship between WSS, age, BMI, gender, race and severity of AA were performed. RESULTS: Of the 274 decedents, 140 had mild and 134 had moderate to severe AA. BMI <35 was associated with moderate to severe AA. WSS was inversely correlated with AA in all these segments of the aorta in each BMI subgroup with the exception of the ascending aorta for decedents with BMI ≤35 kg/m2. Contrary to what we had hypothesized, WSS was not a determinant of the obesity paradox. However, among all the variables analyzed, a history of hypertension, diabetes mellitus and age were significant factors for developing AA (relative risk [RR] 0.35, P = .039; RR 1.51, P = .0006, RR 1.19, P = .0001, respectively). CONCLUSIONS: Our data demonstrate that WSS was unexpectedly lower in decedents with moderate and severe AA as compared to those with mild AA. This observation, which requires further investigations, was seen in all BMI ranges and was confirmed by 2 methods to calculate WSS.

Formalin pre-fixation improves autopsy histology

Microscopic findings in key tissues are often critical to determine the cause of death in medical autopsies. The overall quality of histologic sections depends on numerous pre-analytic factors, among which are tissue section size and thickness. We designed a prospective quality improvement study to determine whether a simple intervention of formalin pre-fixation of myocardium, liver, and kidney tissues could improve the ease of cutting and quality of autopsy histologic sections as assessed by histotechnicians and pathologists. Of 46 autopsies included in the study, 21 were randomly assigned to formalin pre-fixation, and 25 underwent routine sectioning without formalin pre-fixation. A significant improvement in overall quality score by histotechnicians was detected in the sections from pre-fixed autopsy tissues compared to the control group (p=0.0327). There was no significant difference in quality score between the two groups as assessed by pathologists. Our autopsy quality improvement study demonstrates that a simple, low-cost intervention of formalin pre-fixation of fresh autopsy tissues for 90 minutes could significantly improve the overall quality of sections submitted for histologic processing.

ThyroSeq v2 Testing: Impact on Cytologic Diagnosis, Management, and Cost of Care in Patients with Thyroid Nodule.

Background: Novel molecular tests (MTs), such as ThyroSeq, may improve the management of thyroid nodules with indeterminate cytologic diagnoses; however, the impact of these tests on cost and outcome of management is unknown. Here, we evaluated the impact of ThyroSeq testing on the cytopathologic diagnosis, management, and cost of care in patients with thyroid nodules. Methods: In a retrospective study, using actual patient cohorts, the outcome and cost of management of patients with thyroid nodules seen before the introduction of ThyroSeq v2 at our institution (standard of care [StC] cohort) were compared with those seen after the introduction of this test (MT cohort). Results: A total of 773 consecutive patients entered the study (393 StC, 380 MT). The incidence of cytologically benign nodules decreased from 71.0% (StC) to 53.2% (MT) and those of atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS) and follicular neoplasm/suspicious for follicular neoplasm (FN/SFN) increased from 8.9% (StC) to 21.3% (MT) and from 3.1% (StC) to 6.3% (MT), respectively. The overall rate of surgery did not change significantly (23.4% in StC vs. 23.2% in MT). Among patients who underwent surgery, the rate of overtreatment (surgeries performed on histologic benign nodules without clinical indication: compressive symptoms, hyperthyroidism resistant to medication, and nodule size >4 cm) slightly decreased from 18.8% (StC) to 16.7% (MT). The rate of malignancy decreased from 45.5% (StC) to 37.9% (MT) in AUS/FLUS and increased from 40.0% to 53.8% in FN/SFN. However, the overall rate of malignancy remained equal (47.8% in StC vs. 47.7% in MT). The average cost of care per patient in the AUS/FLUS and FN/SFN categories increased from $6,566 (StC) to $8,444 (MT) and from $9,313 (StC) to $10,253 (MT), respectively. Similarly, the overall average cost of care of a patient who underwent thyroid fine-needle aspiration increased from $3,088 (StC) to $4,282 (MT). Finally, the average cost per thyroid cancer detected increased from $26,312 (StC) to $38,746 (MT). Conclusions: Introduction of ThyroSeq v2 resulted in a shift toward indeterminate cytology results. The institutional rate of surgery, overtreatment, and malignancy did not change significantly. Lack of decrease in the rate of surgery along with the additional cost of ThyroSeq v2 increased the overall cost of care of patients including those with indeterminate cytology results.

Clinicopathological complexity in the application of the universal definition of myocardial infarction.

A universal definition of myocardial infarction (UDMI) has been established, periodically updated, and refined over the past twenty years. The primary purpose of the UDMI is to bring uniformity and accuracy to clinical diagnosis. Herein, a review and analysis of the UDMI is presented with emphasis on clinicopathological correlation. Determination of the presence of myocardial injury is based on the detection of abnormal serum cardiac biomarkers, particularly cardiac troponin (cTn), and in the current fourth iteration of the UDMI, high sensitivity (hs)-cTn. Differentiation of myocardial infarction from other causes of myocardial injury requires the documentation of clinical evidence of myocardial ischemia. In this review, difficulties in applying the UDMI in actual practice are discussed, based on the experience and perspective of those of us who face these problems as part of our own practice of pathology. The complexity in application of the UDMI is highlighted by the presentation of five illustrative cases involving the differential diagnosis of myocardial injury and myocardial infarction due to atherothrombotic and nonatherothrombotic coronary artery disease. The cases include myocardial infarction due to severe coronary atherosclerosis, supply-demand mismatch, coronary artery dissection associated with an eosinophilic coronary periarteritis, and coronary thromboembolism, and a case with a differential diagnosis of myocarditis and myocardial infarction. These cases illustrate how pathological findings can contribute to more accurate application of the UDMI and how, when critically applied, the UDMI can be used to better characterize myocardial infarcts in clinical practice.

Limb salvage with CryoVein cadaver saphenous vein allografts used for peripheral arterial bypass: role of blood compatibility.

Patients suffering from limb-threatening ischemia often have scarce or inadequate autogenous veins for complex lower limb revascularization. One option for such patients is to use conduit consisting of cadaver saphenous vein allograft (CSVA) as a final surgical option before limb amputation. This study reviewed retrospectively the patency of CryoVein CSVA allografts, processed by CryoLife, Inc., in 54 implant cases of lower extremity arterial bypass over a span of 6 years. Patient demographics, graft patency, limb salvage, and blood type matching of donor to recipient were analyzed. Kaplan-Meier analysis showed postoperative primary patency rates of 89, 63%, 30%, 17%, and 9% at 1, 3, 6, 12, and 18 months, respectively. Secondary patency rates were 89%, 74%, 63%, 63%, and 54% at 1, 3, 6, 12, and 18 months, respectively. Limb salvage rates were 67% at 12 months and 54% at 18 months. Median follow-up was 467 days. Of the 34 cases where the patient received a blood-group compatible CSVA, 30 had limb salvage and only six of 20 noncompatible grafts offered limb salvage (p = 0.05). Although primary patency rate was poor at 1 year, high secondary patency and limb salvage rates support the use of CSVA as a peripheral bypass conduit alternative. Cases with donor-recipient ABO blood type compatibility had significantly better limb salvage.