Activation of the coagulation cascade after infusion of a factor XI concentrate in congenitally deficient patients

Virally inactivated, high-purity factor XI concentrates are available for treatment of patients with factor XI deficiency. However, preliminary experience indicates that some preparations may be thrombogenic. We evaluated whether a highly purified concentrate produced signs of activation of the coagulation cascade in two patients with severe factor XI deficiency infused before and after surgery. Signs of heightened enzymatic activity of the common pathway of coagulation (elevated plasma levels of prothrombin fragment 1 + 2 and fibrinopeptide A) developed in the early post-infusion period, accompanied by more delayed signs of fibrin formation with secondary hyperfibrinolysis (elevated D-dimer and plasmin-antiplasmin complex). These changes occurred in both patients, but were more severe in the older patient with breast cancer when she underwent surgery, being accompanied by fibrinogen and platelet consumption. There were no concomitant signs of heightened activity of the factor VII-tissue factor mechanism on the factor Xase complex (plasma levels of activated factor VII and of factor IX and X activation peptides did not increase). The observed changes in biochemical markers of coagulation activation indicate that concentrate infusions increased thrombin generation and activity and that such changes were magnified by malignancy and surgery. Because some factor XI concentrates may be thrombogenic, they should be used with caution, especially in patients with other risk factors for thrombosis.     

Angiographic changes in saphenous vein grafts are predictors of clinical outcomes

Background Previous studies have suggested that angiographic evidence of disease progression in coronary arteries increases the risk of subsequent coronary clinical events. This study ascertained whether patients enrolled in the Post Coronary Artery Bypass Graft Clinical Trial (POST CABG) who had substantial progression of atherosclerosis in ≥1 saphenous vein grafts (on the basis of assessment of baseline and follow-up angiograms obtained 4-5 years after study entry), but who had not reported clinical symptoms before follow-up angiography, were at a higher risk of subsequent events than patients who did not have substantial progression of atherosclerosis (decrease ≥0.6 mm in lumen diameter at site of greatest change from baseline). Methods All 1351 patients enrolled in the trial underwent baseline angiography; only the 961 patients who had follow-up angiography and no coronary events before the follow-up study were included in this analysis. The clinical center staff contacted patients to ascertain the events that had occurred after follow-up angiography (approximately 3.4 years later). Results Sixty-nine patients had died; 870 patients or relatives were interviewed, and 22 patients could not be contacted. Univariable estimates of relative risk associated with substantial progression ranged from 2.2 (P < .001) for cardiovascular death or nonfatal myocardial infarction to 3.3 (P < .001) for revascularization. Multivariable and univariable estimates of risk were similar. Conclusions The findings provide evidence that patients who had substantial progression of atherosclerosis in vein grafts are at an increased risk for subsequent coronary events and suggest that angiographic changes in vein grafts are appropriate surrogate measures for clinical outcomes. (Am Heart J 2003;145:262-9.)     

Gamma interferon induces novel expression of Ia antigens by rat pancreatic islet endocrine cells

Pancreatic endocrine cells normally express only Class I gene products of the major histocompatibility complex (MHC). Recently it has been shown that in both patients with recent onset type I diabetes and acutely diabetic BB rats, residual islet beta cells express Class II MHC antigens. In an attempt to define a potential inducer of this aberrant Class II antigen expression, we have investigated the effect of in vitro incubation of rat isolated pancreatic islets with the lymphokine gamma interferon (IFN-gamma) on MHC antigen expression. Our results demonstrate that in vitro exposure to IFN-gamma induces novel expression of Class II antigens on the surface of rat islet endocrine cells and increases the level of pre-existing Class I antigen expression.     

Glioblastoma multiforme with epithelial differentiation: A potential diagnostic pitfall in cerebrospinal fluid cytology

Cerebrospinal fluid (CSF) cytology provides valuable diagnostic and prognostic information for diseases of the central nervous system (CNS) and remains the gold standard for the detection of neoplastic meningitis. Metastatic involvement of the CSF by non‐CNS neoplasms far surpasses that of primary brain tumors, although conventional glioblastoma multiforme (GBM) can occasionally be identified in the CSF. GBM with epithelial differentiation is an uncommon variant that may contain features such as adenoid structures, signet ring cells, or squamous metaplasia. Herein, we present a case of GBM with epithelial differentiation to highlight a potential diagnostic pitfall in CSF cytology. A 55‐year‐old man presented with neurological symptoms and a 6.4 cm left temporal lobe cystic mass. Primary resection revealed GBM with focal epithelial differentiation confirmed by cytokeratin, epithelial membrane antigen, and glial fibrillary acidic protein immunohistochemical studies. Four months following primary resection, the patient developed severe headache for which a lumbar puncture with CSF cytologic evaluation was performed. The cytospin preparation showed numerous malignant epithelioid cells with high nuclear–cytoplasmic ratio and prominent cytoplasmic vacuoles resembling metastatic carcinoma. However, the lesional cells were cytomorphologically identical to the epithelial component present in the patient's recently diagnosed GBM. This case illustrates the potential for GBM with epithelial differentiation to closely mimic metastatic carcinoma from a non‐CNS site in CSF cytology, which expands the differential diagnosis and emphasizes the necessity of clinical correlation. Diagn. Cytopathol. 2015;43:638–641. © 2015 Wiley Periodicals, Inc.     

A case of an atypically large proximal 15q deletion as cause for Prader–Willi syndrome arising from a de novo unbalanced translocation

We describe an 11 month old female with Prader–Willi syndrome (PWS) resulting from an atypically large deletion of proximal 15q due to a de novo 3;15 unbalanced translocation. The 10.6 Mb deletion extends from the chromosome 15 short arm and is not situated in a region previously reported as a common distal breakpoint for unbalanced translocations. There was no deletion of the reciprocal chromosome 3q subtelomeric region detected by either chromosomal microarray or FISH. The patient has hypotonia, failure to thrive, and typical dysmorphic facial features for PWS. The patient also has profound global developmental delay consistent with an expanded, more severe, phenotype.     

Lymphocytes from systemic lupus erythematosus patients display increased spreading on VCAM-1, an effect associated with active renal involvement

The mechanisms underlying leukocyte recruitment in systemic lupus erythematosus (SLE) are unclear. Leukocytes from SLE patients display increased integrin expression, but whether this results in an increased capacity to undergo adhesive interactions has not been investigated. Therefore, the aim of this study was to identify alterations in the capacity of leukocytes from SLE patients to undergo interactions with various substrates under flow conditions. Blood from SLE patients was examined in a flow chamber assay, and rolling, adhesion and post-adhesion spreading assessed on platelet monolayers or VCAM-1. P-selectin-dependent neutrophil rolling on platelet monolayers did not differ between SLE patients and healthy controls. Similarly, lymphocyte adhesion on VCAM-1 did not differ between patients and controls. However, post-adhesion spreading on VCAM-1 was significantly increased in lymphocytes from SLE patients. These parameters were unaffected by overall disease activity, presence of organ damage or prednisolone usage. However, leukocyte spreading on VCAM-1 was elevated in patients with evidence of active renal disease. These findings indicate that lymphocytes from SLE patients have an increased propensity to undergo post-adhesion spreading, a key preliminary step in leukocyte transmigration. This behavior may contribute to lymphocyte infiltration in SLE patients and may represent a novel biomarker of lupus nephritis.