ABSTRACT
BACKGROUND: West Nile virus (WNV) is an emergent pathogen that is widely distributed in North and Central America. The recent introduction in South America has focused attention on the spread of WNV across Southern American countries. The transmission network involves mosquitoes, birds, horses and humans. METHODS: The serological evaluation of sera from 678 equids and 478 birds was performed using a WNV-specific blocking ELISA, and only the positive results were confirmed by plaque reduction neutralisation tests (PRNTs). Molecular analysis was performed on sera from 992 healthy equids and on 63 macerates of brains from equids that died of encephalitis and had previously tested negative for other pathogens. We also tested swabs from 928 birds. The samples analysed were collected in different biomes of Brazil. RESULTS: We identified WNV antibodies by ELISA in thirteen equids and five birds, and PRNT90 confirmed WNV positivity in four equid samples collected in 2009 in an area between the Amazon and the Pantanal. None of the ELISA positive bird samples were confirmed by PRNT90, and all samples tested by RT-PCR were negative. CONCLUSION: WNV circulation is confirmed by this large scale survey even in the absence of detection of clinical cases.
Subject(s)
Antibodies, Viral/blood , West Nile Fever/diagnosis , West Nile Fever/epidemiology , West Nile virus/immunology , Animals , Animals, Wild/immunology , Birds/immunology , Brazil/epidemiology , Culicidae/immunology , Enzyme-Linked Immunosorbent Assay/methods , Horses/immunology , Humans , Seroepidemiologic StudiesABSTRACT
AIMS: Characterization of breast cancer patients with micrometastases in sentinel lymph node (SLN) and establish differences between micrometastatic breast cancers with additional metastatic lymph nodes (LNS) versus no other lymph node invasion. METHODS: Analysis of 30 breast cancers, N1mi or pN0(i+), diagnosed and treated in our department from July 2000 to July 2008. RESULTS: Micrometastases in SLNs were found in 30 patients. Complete axillary dissection revealed other metastatic LNs in 24%. Concerning breast cancers with additional LN invasion versus no other LN invasion, tumors located in the superior-external quadrant were more frequent in the former group. Other characteristics as clinical presentation, histological subtype, focality, cytonuclear grade, hormone receptors and Her2 expression were not significantly different in either group. Regarding SLN invasion, the presence of at least two micrometastatic foci were significantly more relevant in patients with other metastatic LN invasion (p < 0.01). Micrometastases diagnosed only after immunohistochemistry (IHC) were exclusively found in patients without other LN invasion, reaching statistical significance (p < 0.05). CONCLUSIONS: Complete axillary dissection revealed additional LN invasion in 24% of patients with micrometastases in the SLN. Tumors with additional LN invasion were more frequently found in the superior external quadrant and SLNs harbored at least two micrometastatic foci. Micrometastases diagnosed exclusively by IHC techniques were more relevant in cases without additional lymph node invasion.
