Serum Neurofilament to Magnetic Resonance Imaging Lesion Area Ratio Differentiates Spinal Cord Infarction From Acute Myelitis.

BACKGROUND AND PURPOSE: The diagnosis of spontaneous spinal cord infarction (SCI) is limited by the lack of diagnostic biomarkers and MRI features that often overlap with those of other myelopathies, especially acute myelitis. We investigated whether the ratio between serum neurofilament light chain levels and MRI T2-lesion area (neurofilament light chain/area ratio-NAR) differentiates SCI from acute myelitis of similar severity. METHODS: We retrospectively identified Mayo Clinic patients (January 1, 2000-December 31, 2019) with (1) SCI, (2) AQP4 (aquaporin 4)-IgG or MOG (myelin oligodendrocyte glycoprotein)-IgG-associated myelitis at disease clinical presentation, or (3) idiopathic transverse myelitis from a previously identified population-based cohort of patients seronegative for AQP4-IgG and MOG-IgG. Serum neurofilament light chain levels (pg/mL) were assessed at the Verona University (SIMOA, Quanterix) in a blinded fashion on available stored samples obtained ≤3 months from myelopathy presentation. For each patient, the largest spinal cord lesion area (mm2) was manually outlined by 2 independent raters on sagittal T2-weighted MRI images, and the mean value was used to determine NAR (pg/[mL·mm2]). RESULTS: Forty-eight patients were included SCI, 20 (definite, 11; probable, 6; possible, 3); acute myelitis, 28 (AQP4-IgG-associated, 17; MOG-IgG-associated, 5; idiopathic transverse myelitis, 6). The median expanded disability status scale score (range) at myelopathy nadir were 7.75 (2-8.5) and 5.5 (2-8), respectively. Serum neurofilament light chain levels (median [range] pg/mL) in patients with SCI (188 [14.3-2793.4]) were significantly higher compared with patients with AQP4-IgG-associated myelitis (37 [0.8-6942.9]), MOG-IgG-associated myelitis (45.8 [4-283.8]), and idiopathic transverse myelitis (15.6 [0.9-217.8]); P=0.01. NAR showed the highest accuracy for identification of SCI versus acute myelitis with values ≥0.35 pg/(mL·mm2) yielding 86% specificity and 95% sensitivity (area under the curve=0.93). The positive and negative likelihood ratios were 6.67 and 0.06, respectively. NAR remained independently associated with SCI after adjusting for age, gender, immunotherapy before sampling, and days from myelopathy symptoms onset to sampling (P=0.0007). CONCLUSIONS: NAR is a novel and promising clinical biomarker for differentiation of SCI from acute myelitis.

PR3 vasculitis presenting with symptomatic splenic and renal infarction: a case report and literature review.

BACKGROUND: ANCA-associated vasculitis is a life-threatening, systemic autoimmune disease. There is an increased risk of organ infarction but in many cases this is asymptomatic. We described here the first reported case of PR3 vasculitis presenting with symptomatic bilateral renal wedge infarction. CASE PRESENTATION: A 19-year old Caucasian woman with no past medical history presented on a number of occasions over a number of weeks with progressively more severe back pain, fevers and arthralgia. On the final presentation she was noted to have developed splinter haemorrhages and her blood tests revealed impaired renal function along with elevated inflammatory markers. She was subsequently found to have high titres of serum PR3 antibodies and focal necrotising glomerulonephritis on renal biopsy, consistent with a diagnosis of PR3 ANCA-associated vasculitis. Cross-sectional imaging revealed multiple wedge infarcts of her spleen and both kidneys, confirmed on contrast-enhanced ultrasound. Large vessel, cardiac and thrombophilic causes of thromboembolism were excluded. She was treated with high-dose corticosteroids and CD20 monoclonal antibodies (rituximab) and at time of writing, 4 months after initial presentation, has entered clinical remission. CONCLUSIONS: Here we describe the first reported case of PR3 vasculitis presenting with symptomatic renal wedge infarction. In patients with vasculitis who present with flank or back pain, infarction of abdominal organs should be considered in the differential. Both splenic and renal infarctions are likely underdiagnosed in the setting of ANCA-associated vasculitis but may have clinical impact in contributing to infection risk and the degree or renal recovery, respectively.

Association Between Troponin Levels and Visceral Infarction in Patients with Acute Ischemic Stroke.

BACKGROUND: Visceral infarctions appear to be more common in patients with embolic stroke subtypes, but their relation to troponin elevation remains uncertain. METHODS: Among patients with acute ischemic stroke enrolled in the Cornell AcutE Stroke Academic Registry (CAESAR) from 2011 to 2016, we included those with troponin measured within 24 hours from stroke onset and a contrast-enhanced abdominal computed tomographic scan within 1 year of admission. A troponin elevation was defined as a value exceeding our laboratory's upper limit of normal (.04 ng/ mL) in the absence of a clinically recognized acute ST-segment elevation myocardial infarction. Visceral infarction was defined as a renal or splenic infarction as ascertained by a single radiologist blinded to patients' other characteristics. Multivariable logistic regression was used to evaluate the association between elevated troponin and visceral infarction. RESULTS: Among 2116 patients registered in CAESAR from 2011 to 2016, 153 patients had both a troponin assay and a contrast-enhanced abdominal computed tomographic scan, of whom 33 (21%) had an elevated troponin and 22 (14%) had a visceral infarction. The prevalence of visceral infarction was higher among patients with an elevated troponin (30%; 95% confidence interval [CI], 16%-49%) than among patients without an elevated troponin (10%; 95% CI, 5%-17%) (P = .003). After adjustment for demographics and comorbidities, we found a significant association between elevated troponin and visceral infarction (odds ratio, 3.9; 95% CI, 1.5-10.4). CONCLUSIONS: Among patients with acute ischemic stroke, elevated troponin was associated with visceral infarction. Our results demonstrate that poststroke troponin elevation may indicate the presence of underlying embolic sources.

Serum Troponin Level in Acute Ischemic Stroke Identifies Patients with Visceral Infarcts.

BACKGROUND AND PURPOSE: Patients with ischemic stroke of cardioembolic origin are at risk of visceral (renal or splenic) infarction. We hypothesized that serum troponin level at time of ischemic stroke would be associated with presence of visceral infarction. METHODS: Data were abstracted from a single center prospective stroke database over 18 months and included all patients with ischemic stroke who underwent contrast-enhanced computerized tomography (CT) of the abdomen and pelvis for clinical purposes within 1 year of stroke. The primary predictor was troponin concentration ≥.1ng/mL. The primary outcome was visceral infarct (renal and/or splenic) on CT abdomen and pelvis. Univariate and multivariable logistic regression models were used to estimate the odds ratio and 95% confidence intervals (OR, 95% CI) for the association of troponin with visceral infarction. RESULTS: Of 1233 patients with ischemic stroke, 259 patients had a qualifying visceral CT. Serum troponin level on admission was measured in 237 of 259 patients (93.3%) and 41 of 237 (17.3%) had positive troponin. There were 25 patients with visceral infarcts: 16 renal, 7 splenic, and 2 both. In univariate models, patients with a positive troponin level (versus negative) were more likely to have visceral infarcts (39.1% [9/23] versus 15.0% [32/214], P = .008) and this association persisted in multivariable models (adjusted OR 3.83; 95% CI 1.42-10.31, P = .006). CONCLUSIONS: In ischemic stroke patients, elevated serum troponin levels may help identify patients with visceral infarcts. This suggests that troponin in the acute stroke setting is a biomarker of embolic risk. Larger studies with systematic visceral imaging are needed to confirm our findings.

Utility of Neutrophil-to-Lymphocyte Ratio (NLR) as a Predictor of Acute Infarction in New-Onset Acute Vertigo Patients Without Neurologic and Computed Tomography Abnormalities.

BACKGROUND: Neutrophil-to-lymphocyte ratio (NLR) has been used as a predictive marker for various conditions. However, there are no previous studies about NLR as a prognostic marker for acute infarction. OBJECTIVE: To evaluate the potential utility of NLR as a predictor of acute infarction in acute vertigo patients without neurologic and computed tomography (CT) abnormalities. METHODS: We conducted a prospective, observational study in the Emergency Department (ED) between January 2015 and December 2016. All patients underwent physical examination, laboratory tests, CT, and magnetic resonance imaging (MRI). Results of the initial and follow-up MRI with clinical progress note were considered as the reference standard. Statistically, multivariate logistic regression analysis and receiver operating characteristic (ROC) curve were used. RESULTS: Thirty-five (25.9%) patients were diagnosed with acute infarction and 100 (74.1%) patients were diagnosed with peripheral vertigo. Horizontal nystagmus (p = 0.03; odds ratio 0.22) and NLR (p = 0.03; odds ratio 5.4) were significant factors for the differential diagnosis of acute infarction and peripheral vertigo. NLR > 2.8 showed the greatest area under the ROC curve (AUC; 0.819), optimal sensitivity (85.7%), and specificity (78.0%). NLR > 1.4 showed the highest sensitivity (97.1%) and relatively low specificity (41%). The absence of horizontal nystagmus increased the specificity (81.0%) and AUC (0.844). CONCLUSIONS: A combination of NLR > 2.8 and the absence of horizontal nystagmus is sufficiently specific for acute infarction in an ED patient with acute vertigo; thus, further testing with MRI is indicated. NLR < 2.8 by itself or combined with the presence of horizontal nystagmus is not sufficiently sensitive to rule out the need for further testing.

Predictive Factors of Intestinal Necrosis in Acute Mesenteric Ischemia: Prospective Study from an Intestinal Stroke Center.

OBJECTIVES: To identify predictive factors for irreversible transmural intestinal necrosis (ITIN) in acute mesenteric ischemia (AMI) and establish a risk score for ITIN. METHODS: This single-center prospective cohort study was performed between 2009 and 2015 in patients with AMI. The primary outcome was the occurrence of ITIN, confirmed by specimen analysis in patients who underwent surgery. Patients who recovered from AMI with no need for intestinal resection were considered not to have ITIN. Clinical, biological and radiological data were compared in a Cox regression model. RESULTS: A total of 67 patients were included. The origin of AMI was arterial, venous, or non-occlusive in 61%, 37%, 2% of cases, respectively. Intestinal resection and ITIN concerned 42% and 34% of patients, respectively. Factors associated with ITIN in multivariate analysis were: organ failure (hazard ratio (HR): 3.1 (95% confidence interval (CI): 1.1-8.5); P=0.03), serum lactate levels >2 mmol/l (HR: 4.1 (95% CI: 1.4-11.5); P=0.01), and bowel loop dilation on computerized tomography scan (HR: 2.6 (95% CI: 1.2-5.7); P=0.02). ITIN rate increased from 3% to 38%, 89%, and 100% in patients with 0, 1, 2, and 3 factors, respectively. Area under the receiver operating characteristics curve for the diagnosis of ITIN was 0.936 (95% CI: 0.866-0.997) depending on the number of predictive factors. CONCLUSIONS: We identified three predictive factors for irreversible intestinal ischemic injury requiring resection in the setting of AMI. Close monitoring of these factors could help avoid unnecessary laparotomy, prevent resection, as well as complications due to unresected necrosis, and possibly lower the overall mortality.

Nonocclusive mesenteric infarction after cardiac surgery: potential biomarkers.

BACKGROUND: Nonocclusive mesenteric ischemia can cause intestinal infarction but the diagnosis is challenging. This prospective study evaluated three plasma biomarkers of intestinal infarction after cardiac surgery. MATERIALS AND METHODS: Patients were recruited after cardiac surgery if they required laparotomy (with or without intestinal resection) for suspected nonocclusive mesenteric ischemia. Plasma levels of D-lactate, intestinal fatty acid-binding protein (i-FABP), and smooth muscle actin (SMA) before laparotomy were measured. RESULTS: Twenty patients were recruited (68 ± 9 y, EuroSCORE: 8.7 ± 2.8, mortality 70%). A positive laparotomy (n = 13) was associated with no change in D-lactate (P = 0.95), decreased i-FABP (P = 0.007), and increased SMA (P = 0.01). All patients with high SMA had a positive laparotomy. A subgroup analysis was undertaken in the eight patients who required multiple laparotomies. D-lactate increased between the two laparotomies in nonsurvivors (n = 4). Plasma i-FABP (P = 0.008) and SMA (P = 0.036) significantly decreased after the bowel resection, regardless of survival outcome. CONCLUSIONS: None of the biomarkers were accurate enough to reliably diagnose intestinal infarction. However, all patients with high values of SMA developed intestinal infarction, thus warranting further investigation. An increasing D-lactate after intestinal resection suggests impending death.

A case series of acute renal infarction at a single center in Japan.

BACKGROUND: The prevalence of acute renal infarction (ARI) in Japan remains unclear. We describe the clinical features and renal prognosis of ARI in Japanese patients. METHODS: This single-center, retrospective, observational study included 33 patients with newly diagnosed ARI (2009-2013). Their clinical features and long-term renal outcomes were evaluated. RESULTS: The prevalence of ARI among emergency room patients was 0.013 %. The incidence of ARI among in-patients was 0.003 % (mean age 71.9 ± 13.4 years; men 63 %). Enhanced computed tomography or renal isotope scans were obtained to diagnose ARI. ARI involved the left kidney in 70 %, right kidney in 18 %, and both kidneys in 12 % of patients. Four cases had splenic infarction, and 70 % of patients had atrial fibrillation. We noted abdominal or flank pain in 66 %, fever (>37.6 °C) in 36 %, and nausea/vomiting in 6 % of patients. The white blood cell count, and levels of lactate dehydrogenase and C-reactive protein peaked at 2-4 days after onset. Acute kidney injury due to ARI occurred in 76 % of patients. The estimated glomerular filtration rate decreased to ~70 % and recovered to ~80 % of the original value after 1 year. The mortality rates were 9 and 15 % at 1 month and 1 year, respectively. CONCLUSIONS: We determined the prevalence of ARI among emergency room patients, its incidence among in-patients, and short-term and long-term mortality. The majority of ARI cases were of cardiac origin, and the others were due to trauma or systemic thrombotic disease. Clinicians should recognize ARI as a fatal arterial thrombotic disease.

[Clinical analysis of syndrome-relative biological indices in acute lacuna encephalon infarction patients of upper hyperactivity of Gan Yang syndrome].

OBJECTIVE: To analyze and summarize changes of syndrome-related biological indices in acute lacuna encephalon infarction patients of upper hyperactivity of Gan yang syndrome (UHGYS), thus providing objective evidence for syndrome typing and disease identification. METHODS: Recruited were 50 patients at Department of Encephalopathy, Xiyuan Hospital, China Academy of Chinese Medical Sciences, who were in line with diagnostic criteria of UHGYS as the experimental group in this study. Another 40 healthy volunteers were recruited as the control group from May 2010 to July 2012. Blood routines (including WBC, RBC, Hb, NEUT%, and LY%), hepatic and renal functions tests (including ALT, AST, TBIL, TP, ALB, Cr, and BUN) were performed by automatic whole blood analyzer and colorimetric technique. The levels of fasting blood glucose, HbAlc, blood lipids (including TC, TG, HDL-C, LDL-C, and VLDL-C), and coagulation functions (including AT-III, PT, PTA, INR, TT, APTT, and FBG, reaction time), renin, angiotensin II, hs-CRP, and Hcy were also measured. The thyroid functions (including FT3, FT4, T3, T4, and TSH) were detected by electrochemiluminescence immunoassay. The levels of tumor necrosis factor alpha (TNF-alpha), IL-6 and IL-1 in serum were measured by ELISA and radioimmunoassay respectively. RESULTS: Compared with the control group, RBC, LY%, ALT, TP, ALB, HDL-C, AT-III activities, contents of PTA and FT4 obviously decreased, TBIL, BUN, Glu, HbAlc, TSH, hs-CRP, renin, Ang II, TNF-alpha, IL-1 and IL-6 significantly increased in the experimental group (P < 0.05, P < 0.01). CONCLUSION: The pathological process of acute lacuna encephalon infarction patients of UHGYS was closely correlated with thyroid functions, the renin-angiotensin-aldosterone system, the extrinsic and intrinsic coagulation systems, as well as inflammation reaction.

A case of renal infarction associated with elevated factor VIII level.

Elevated factor VIII level has recently been shown to be associated with increased risk of thrombosis. We report here a case of renal infarction in association with elevated factor VIII level. The patient presented with a three-day history of flank pain. Laboratory studies on presentation showed an elevated serum creatinine concentration and microscopic hematuria. He was found to have bilateral pulmonary emboli and left common femoral vein thrombosis; imaging studies showed evidence of renal arterial thrombosis with infarction. Hypercoagulability assessment showed an elevated factor VIII level. He was treated with heparin and warfarin with significant improvement in his renal function. Consideration should be given to measurement of factor VIII level as a part of the workup of unexplained thrombo-embolic events.

Early critical cortical infarction by anti-angiotensin II type 1 receptor antibody: A case report and literature review.

RATIONALE: Anti-angiotensin II type 1 receptor antibodies (AT1R-Abs) have been demonstrated to increase the risk of antibody-mediated rejection. We report a case of AT1R-Ab mediated rejection which caused early critical cortical infarction. PATIENT CONCERNS: A 52-year-old man with end-stage kidney disease underwent preemptive kidney transplantation (KT) from his wife. He had no immunologic risk except ABO incompatibility. Proper desensitization treatment were applied prior to KT. On postoperative day 1, he showed stable clinical course with adequate urine output, but there was no decrease in serum creatinine level and imaging studies showed hypoperfusion in the transplanted kidney. DIAGNOSES: Allograft biopsy revealed total cortical infarction with severe necrotizing vasculitis, but the medullary area was preserved. Serum AT1R-Ab concentration was elevated from 10.9 U/mL before KT to 19.1 U/mL on 7 days after KT. INTERVENTIONS: He was treated with plasmapheresis, intravenous immunoglobulin, rituximab, high-dose methylprednisolone, and bortezomib. OUTCOMES: The treatment showed a partial response, and he was discharged with 7.3 mg/dL creatinine level. At 4 months, his creatinine plateaued at 5.5 mg/dL and AT1R-Ab decreased to 3.6 U/mL. LESSONS: This case highlights the risk of early active antibody-mediated rejection by preformed AT1R-Ab, suggesting its ability to exhibit atypical histopathologic findings, such as total cortical infarction.

[Early diagnosis in acute mesenteric ischemia. Case series and clinical review]. / Diagnosi precoce nell'ischemia mesenterica acuta. Casistica e revisione clinica.

The AA report on 12 cases of intestinal infarction for acute mesenteric ischemia (IMA) in critical patients observed in the last 2 years. In this work some clinical data, blood tests and strumental considerations are described. IMA is a vascular emergency with severe prognosis and high rate morbidity and mortality, often correlated to a diagnostic delay. The discrepancy between symptoms and clinical objectivity must suggest the suspect, especially in patients with cardiac pathology, short lasting diarrhoea, bowel hemorrhage or only abdominal pain rebel to the analgesics; with the laboratory indexes and strumental data it can be carried out an early diagnosis and then begin the more opportune therapeutical treatment. The increase of blood sugar together to the triad leucocytosis--haemoconcentration and metabolic acidosis, in previously non diabetic patients, confirm the suspect of IMA in the very initial phases of this pathology.

A practical approach to infarction of the spleen as a rare manifestation of multiple common diseases.

INTRODUCTION: There are insufficient data on the aetiologic factors underlying splenic infarction (SI). Therefore, there is no consensus regarding the appropriate diagnostic approach. METHODS: We conducted a retrospective analysis of all patients admitted with SI from January 2004 to December 2014. Medical records were screened for the clinical presentation, underlying causes, associated medical conditions and methods of patient evaluation. RESULTS: We found 89 subjects with 90 episodes of SI. Presentation of SI was characterized by abdominal, flank and chest pain (82.2%, 18.9%, 7.8%, respectively); leukocytosis (in 67% of tested subjects); elevated LDH (72%), CRP (97.5%) and D-Dimer (100%). The main underlying mechanisms were cardioembolic (54.4%), vascular (20%), haematologic disorders (15.6%) and multiple causes (21.1%). Atrial fibrillation and atherosclerosis were common in older patients (age > 70 years) while antiphospholipid syndrome occurred exclusively in younger individuals. SI was the presentation of previously unknown medical conditions in 38% of patients. Abdominal CT, ECG, echocardiography and blood cultures demonstrated the highest diagnostic yield. CONCLUSIONS: Contributing factors are identified in the majority of SI patients. We recommend CT, ECG, echocardiography and blood cultures in all cases. Atrial fibrillation should be sought in older patients, while APLS and haematologic disorders should be suspected in younger ones. KEY MESSAGES There is no consensus regarding the diagnostic approach and management of splenic infarction. Cardiovascular disease and atrial fibrillation are the main causes for SI in elderly subjects while hematological, infectious and other causes are more prevalent in younger ones. Our data strongly suggests a high diagnostic yield for CT scan, ECG, blood culture and echocardiogram in every patient with SI.

Factors influencing mortality of acute intestinal infarction associated with SIRS.

BACKGROUND/AIMS: In patients with acute mesenteric ischemia, early diagnosis is considered to improve the prognosis by preventing the occurrence of systemic inflammatory response syndrome (SIRS). However, it remains unclear which factors affect the mortality once advanced ischemia and SIRS develop in cases of delayed diagnosis. The aim of this study was to investigate the predictors of in-hospital mortality in the late stage of acute mesenteric ischemia. METHODOLOGY: We retrospectively studied 66 consecutive patients who had acute intestinal infarction associated with SIRS between 1986 and 2002. They included 19 of acute mesenteric thromboembolism and 47 cases of postoperative adhesions or an incarcerated hernia. A multivariate logistic model was used to identify important factors for in-hospital death among the background data. Two models were constructed with/without the cause of intestinal obstruction as a variable, since it might affect the prognosis. RESULTS: The results suggested that concomitant cardiac morbidity, high serum amylase level, and thrombocythemia are important factors for in-hospital mortality of acute intestinal infarction, regardless of the cause of intestinal infarction. CONCLUSIONS: Our results indicated that the prognosis is strongly influenced by associated cardiac morbidity and abnormal coagulopathy in the advanced stage of mesenteric ischemia.

Silent pituitary apoplexy: subclinical infarction of an adrenocorticotropin-producing pituitary adenoma.

A young woman developed intermittent headaches and progressive hyperpigmentation after bilateral adrenalectomy for Cushing's disease. Results of sellar polytomography were abnormal. Her plasma ACTH levels increased to 4750-7340 pg/ml and did not rise with insulin-induced hypoglycemia. Although she experienced no clinical features associated with spontaneous infarction of a pituitary tumor, plasma ACTH levels fell to 474-575 pg/ml, and hemorrhagic necrosis was found in a 5-mm chromophobe adenoma at transsphenoidal surgery. Postoperatively, ACTH levels returned to normal (51-88 pg/ml), with the rest of her anterior pituitary function remaining intact 4 yr later. Spontaneous infarction of pituitary microadenomas may be subclinical, resulting in improvement of pituitary hormone hypersecretion without impairment of other anterior pituitary hormone secretion.

Diabetic thigh muscle infarction in association with antiphospholipid antibodies.

BACKGROUND: Diabetic muscle infarction (DMI) is a rare complication of type 1 diabetes mellitus. DMI has a stereotyped clinical presentation and characteristic, though nonspecific, magnetic resonance imaging (MRI) and histologic findings. The etiology, however, remains controversial. OBJECTIVES: To present the first reported cases of DMI in association with positive antiphospholipid (aPL) antibody titers and to discuss the etiologic and pathogenic significance of the association between type 1 diabetes and aPL antibodies. METHODS: Descriptive case reports of 2 patients with DMI and positive aPL antibodies and a review of the relevant literature. RESULTS: Our 2 patients with DMI are female type-1 diabetics with end-organ microvascular complications who presented with an abrupt, painful swelling or mass of the thigh musculature. The diagnosis of DMI was based on the clinical picture and the findings on T2-weighted MRI and histologic evaluation. The first patient had a long history of known aPL antibodies in the setting of systemic lupus erythematosus. The second patient was only determined to be aPL positive after her recurrent episodes of DMI. The first patient was treated with anticoagulation and corticosteroids with relatively rapid resolution of symptoms. The second patient was treated with local débridement and supportive care with a resulting course of prolonged symptoms and recurrences. There are no controlled trials of the treatment of DMI. In the literature there is evidence for an increased prevalence of aPL antibodies in type 1 diabetic patients. The pathogenesis of DMI is poorly understood, but the hypercoagulable state often associated with aPL antibodies may play an important role. CONCLUSIONS/RELEVANCE: aPL antibodies may be involved in the pathogenesis of diabetic muscle infarction and could serve as an important target of therapeutic intervention, namely with anticoagulation.

Leukocytosis in acute pulmonary embolism.

PURPOSE: The purpose of this investigation is to assess the level of leukocytosis in acute pulmonary embolism (PE). BACKGROUND: Limited data exist regarding leukocytosis in acute PE. One reason that the prevalence of leukocytosis in acute PE is unknown, despite an extensive number of investigations of PE, may relate to the fact that acute PE is usually associated with other conditions that themselves may cause leukocytosis. METHODS: Hospital records of 386 patients with a diagnosis of acute PE were reviewed retrospectively. Patients with no other possible or definite cause of leukocytosis were analyzed separately. A diagnosis of PE was made by a high-probability interpretation of the ventilation/perfusion lung scan or pulmonary angiogram. RESULTS: Among patients with PE in whom other possible or defined causes for leukocytosis were eliminated, 52 of 266 (20%) had a WBC count > 10,000/mm3. None had a WBC count that was > or = 20,000/mm3. Patients with the pulmonary hemorrhage/infarction syndrome had an increased WBC count in 32 of 183 (17%) vs 20 of 83 (24%) in patients who did not have pulmonary hemorrhage/infarction syndrome (not significant). CONCLUSION: A modest leukocytosis may accompany (and possibly be caused by) PE. Its presence should not dissuade the clinician from objectively pursuing the diagnosis of PE.

Lymph-node infarction in two young men.

Benisch, Barry M., and Howard Rudolf G.: Lymph-node infarction in two young men. Am J Clin Pathol 63: 818-823, 1975. Two cases of massive lymph-node infarction in young men are described. Both patients had fever and lymphadenopathy and findings that suggested the possibility of viral infection. Follow up has revealed both patients to be asymptomatic, with lymphadenopathy, and with normal laboratory findings.

Two cases with renal infarction diagnosed in the early course using contrast-enhanced CT.

We experienced two cases of renal infarction with atrial fibrillation who presented with acute abdominal pain. On initial urinalysis, both patients showed no hematuria, but the plasma lactate dehydrogenase level was markedly elevated with little or no rise in plasma transaminases. Their diagnosis was confirmed by contrast-enhanced CT of the abdomen on the second and third days of the crisis. We immediately initiated anticoagulant therapy, resulting in successful prevention of new embolism. Contrast-enhanced CT should be considered if abdominal symptoms develop in patients with atrial fibrillation. Renal infarction could be diagnosed in the early course, even in cases with incomplete occlusion of the renal arteries and normal renal function.