An HIV Diagnostic Testing Algorithm Using the cobas HIV-1/HIV-2 Qualitative Assay for HIV Type Differentiation and Confirmation.

Human immunodeficiency virus types 1 and 2 (HIV-1 and HIV-2) diagnostic testing algorithms recommended by the Centers for Disease Control involve up to three tests and rely mostly on detection of viral antigen and host antibody responses. HIV-1 p24 antigen/HIV-1/HIV-2 antibody-reactive specimens are confirmed with an immunochromatographic HIV-1/HIV-2 antibody differentiation assay, and negative or indeterminate results from the differentiation assay are resolved by an HIV-1-specific nucleic acid amplification test (NAT). The performance of a proposed alternative algorithm using the cobas HIV-1/HIV-2 qualitative NAT as the differentiation assay was evaluated in subjects known to be infected with HIV-1 (n = 876) or HIV-2 (n = 139), at low (n = 6,017) or high (n = 1,020) risk of HIV-1 infection, or at high-risk for HIV-2 infection (n = 498) (study A). The performance of the cobas HIV-1/HIV-2 qualitative test was also evaluated by comparison to an HIV-1 or HIV-2 alternative NAT (study B). The HIV-1 and HIV-2 overall percent agreements (OPA) in study A ranged from 95% to 100% in all groups. The positive percent agreements (PPA) for HIV-1 and HIV-2 were 100% (876/876) and 99.4% (167/168), respectively, for known positive groups. The negative percent agreement in the HIV low-risk group was 100% for both HIV-1 and HIV-2. In study B, the HIV-1 and HIV-2 OPA ranged from 99% to 100% in all groups evaluated (n = 183 to 1,030), and the PPA for HIV-1 and HIV-2 were 100% and 99.5%, respectively, for known positive groups. The cobas HIV-1/HIV-2 qualitative assay can discriminate between HIV-1 and HIV-2 based on HIV RNA and can be included in an alternative diagnostic algorithm for HIV.

Impact of monitoring longitudinal systolic strain changes during serial echocardiography on outcome in patients with AL amyloidosis.

Relative apical sparing of longitudinal systolic strain (LSsys) with preserved LSsys at apical and significantly reduced LSsys at mid/basal segments is a typical echocardiographic feature in AL amyloidosis patients with cardiac involvement. The present study aims to evaluate the change of this typical feature over time by serial echocardiography and its impact on outcome in AL amyloidosis patients with cardiac involvement. Echocardiography was performed in 24 consecutive patients with biopsy-proven AL amyloidosis (mean age 64 ± 9 years; 50% male) at baseline and during a median of 257 (quartiles 103-651) days follow-up. Global and segmental LSsys were assessed by two-dimensional speckle-tracking-imaging in septal and lateral segments of the left ventricle (LV) from the apical 4-chamber view. Sixteen (67%) patients died during a median follow-up of 487 days (quartiles 223-872). LV global and segmental LSsys remained unchanged over time in survivors (all P > 0.05), while LV global, septal-apical and lateral-apical LSsys significantly decreased in non-survivors. A decrease in lateral-apical LSsys > 3.0% independently predicted a fivefold increased all-cause mortality risk after adjustment for age, gender, NYHA class, and treatment strategies. Further, baseline serum NT-proBNP, serum albumin decrease during follow-up, baseline septal apical-to-basal LSsys ratio and lateral-apical LSsys decrease during follow-up remained independently predictive of increased all-cause mortality risk. Serial monitoring of serological and echocardiographic parameters is valuable to predict outcome in AL amyloidosis patients with cardiac involvement. The best follow-up parameter to predict risk for imminent death is a decrease of longitudinal systolic strain at the lateral apical segment.

The cardiomyopathy in Friedreich's ataxia - New biomarker for staging cardiac involvement.

BACKGROUND: Patients with autosomal-recessively inherited Friedreich's ataxia (FA) may develop a hypertrophic cardiomyopathy (CM), which potentially progresses towards a life-limiting problem. The typical features of this CM and the sequence of progression are widely unknown. METHODS: Thirty-two consecutive patients with genetically confirmed FA were included. All patients received resting electrocardiogram (ECG), 24-hour Holter-ECG, echocardiography with speckle tracking imaging, cardiac magnetic resonance imaging (cMRI) with late enhancement imaging (for replacement fibrosis), and measurement of high-sensitive troponin-T (hsTNT). In addition, morphological parameters were retrospectively compared to data obtained five years before. RESULTS: Based on criteria comprising ejection fraction (<55%), left ventricular end-diastolic posterior wall thickness (LVPWT ≥ 11 mm), fibrosis on cMRI, hsTNT ≥ 14 ng/ml, or T-wave-inversion, in all but two patients a CM could be detected (94%). Using these criteria we propose the following staging: a) mild CM (n=5, 16%; T-wave-inversion only); b) intermediate CM (n=4, 13%; T-wave-inversion with hypertrophy but no fibrosis); c) severe CM (n=13, 41%; fibrosis with raised hsTNT); and d) end-stage CM (n=8; 25%; ejection-fraction<55%). All patients with end-stage CM also showed fibrosis on cMRI, T-wave-inversion, marked elevation in hsTNT, and a decrease in LVPWT during the last five years (from 10.7 ± 1.2mm to 9.5 ± 1.3mm, p=0.025). In addition, 38% suffered from supraventricular tachycardia on Holter-ECG. CONCLUSIONS: A comprehensive cardiac assessment will unravel established CM in almost all patients with FA with electrocardiographic abnormalities as earliest signs. Advanced stages can be characterized by elevated hsTNT and replacement fibrosis leading to recession of hypertrophy, reduction of global myocardial function, and electrical instability.

Predictive value of assessing diastolic strain rate on survival in cardiac amyloidosis patients with preserved ejection fraction.

OBJECTIVES: Since diastolic abnormalities are typical findings of cardiac amyloidosis (CA), we hypothesized that speckle-tracking-imaging (STI) derived longitudinal early diastolic strain rate (LSRdias) could predict outcome in CA patients with preserved left ventricular ejection fraction (LVEF >50%). BACKGROUND: Diastolic abnormalities including altered early filling are typical findings and are related to outcome in CA patients. Reduced longitudinal systolic strain (LSsys) assessed by STI predicts increased mortality in CA patients. It remains unknown if LSRdias also related to outcome in these patients. METHODS: Conventional echocardiography and STI were performed in 41 CA patients with preserved LVEF (25 male; mean age 65±9 years). Global and segmental LSsys and LSRdias were obtained in six LV segments from apical 4-chamber views. RESULTS: Nineteen (46%) out of 41 CA patients died during a median of 16 months (quartiles 5-35 months) follow-up. Baseline mitral annular plane systolic excursion (MAPSE, 6 ± 2 vs. 8 ± 3 mm), global LSRdias and basal-septal LSRdias were significantly lower in non-survivors than in survivors (all p < 0.05). NYHA class, number of non-cardiac organs involved, MAPSE, mid-septal LSsys, global LSRdias, basal-septal LSRdias and E/LSRdias were the univariable predictors of all-cause death. Multivariable analysis showed that number of non-cardiac organs involved (hazard ratio [HR] = 1.96, 95% confidence interval [CI] 1.17-3.26, P = 0.010), global LSRdias (HR = 7.30, 95% CI 2.08-25.65, P = 0.002), and E/LSRdias (HR = 2.98, 95% CI 1.54-5.79, P = 0.001) remained independently predictive of increased mortality risk. The prognostic performance of global LSRdias was optimal at a cutoff value of 0.85 S-1 (sensitivity 68%, specificity 67%). Global LSRdias < 0.85 S-1 predicted a 4-fold increased mortality in CA patients with preserved LVEF. CONCLUSIONS: STI-derived early diastolic strain rate is a powerful independent predictor of survival in CA patients with preserved LVEF.

MAP kinase signalling pathway components and targets conserved between the distantly related plant pathogenic fungi Mycosphaerella graminicola and Magnaporthe grisea.

Mycosphaerella graminicola is a dimorphic fungus which causes Septoria tritici leaf blotch. This report describes the examination of the role of several components of the Pmk1p/Fus3p mitogen-activated protein kinase (MAPK) signalling pathway in the development of this species. The genes encoding the MAPK kinase kinase MgSte11p and the MAPK kinase MgSte7p were found to be indispensible for pathogenicity while the deletion of the gene encoding the proposed scaffold protein MgSte50p led to a reduction in virulence. These phenotypes were attributed to a reduced ability to form filaments on the plant surface which prevented penetration. A delayed disease progression was observed on deletion of the gene MGSTE12. The MGSTE7, MGSTE50 and MGSTE12 genes were able to complement mutants of Magnaporthe grisea lacking the orthologous genes. Interactions between the My. graminicola signalling components were also investigated. Furthermore genes whose MgSte12p/Mst12p dependence is conserved between My. graminicola and Ma. grisea were identified.