Δευτέρα 26 Δεκεμβρίου 2022

Bartonella quintana transmitted by head lice: an outbreak of trench fever in Senegal

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Abstract
Background
Louse-borne trench fever caused by Bartonella quintana is a neglected public health concern, known to be transmitted from body louse faeces via scratching. No viable B. quintana have ever been isolated from head lice before; therefore, their role as a vector is still poorly understood.
Methods
In Senegal, the implementation of a permanent local surveillance system in a Point-of-Care laboratory (POC) allows the monitoring of emerging diseases. Here, we used culture as well as molecular and genomic approaches to document an outbreak of trench fever associated with head lice in the village of Ndiop. Head lice and blood samples were collected from febrile patients between November 2010 and April 2015. Genomes of two isolated strains of B. quintana were sequenced and analysed.
Results
A total of 2,289 blood samples were collected in the 2010-2015 period. From 2010-2013, B. quintana DNA was detected by PCR in 0.25% (4/1,580). In 2014, 228 blood samples were collected, along with 161 head lice from five individuals. B. quintana DNA was detected in 4·4% (10/228) of blood samples, and in lice specimens collected from febrile patients (61·7%, 50/81) and non-febrile patients (61·4%, 43/70). Two B. quintana strains were isolated from blood and head lice from two different patients. Genomic sequence analysis showed 99·98% overall similarity between both strains.
Conclusion
The presence of live B. quintana in head lice, and the genetic identity of strains from patients' blood and head lice during a localised outbreak in Senegal, supports the evidence of head lice vectorial capacity.
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Mitotic count is prognostic in IDH-mutant astrocytoma without homozygous deletion of CDKN2A/B. Results of consensus panel review of EORTC trials 26053 and EORTC 22033-26033

alexandrossfakianakis shared this article with you from Inoreader
Abstract
Background
Gliomas with IDH1/2 mutations without 1p19q codeletion have been identified as the distinct diagnostic entity of IDH mutant astrocytoma (IDHmut astrocytoma). Homozygous deletion of Cyclin-dependent kinase 4 inhibitor A/B (CDKN2A/B) has recently been incorporated in the grading of these tumors. The question of whether histologic parameters still contribute to prognostic information on top of the molecular classification, remains unanswered. Here we evaluated consensus histologic parameters for providing additional prognostic value in IDHmut astrocytomas.
Methods
An international panel of seven neuropathologists scored 13 well-defined histologic features in virtual microscopy images of 192 IDHmut astrocytomas from EORTC trial 22033-26033 (low-grade gliomas) and 263 from EORTC 26053 (CATNON) (1p19q non-codeleted anaplastic glioma). For 192 gliomas the CDKN2A/B status was known. Consensus (agreement ≥ 4/7 panelists) hi stologic features were tested together with homozygous deletion (HD) of CDKN2A/B for independent prognostic power.
Results
Among consensus histologic parameters, the mitotic count (cut-off of 2 mitoses per 10 high power fields standardized to a field diameter of 0.55 mm and an area of 0.24 mm 2) significantly influences PFS (p = 0.0098) and marginally the OS (p = 0.07). Mitotic count also significantly affects the PFS of tumors with HD CDKN2A/B, but not the OS, possibly due to limited follow-up data.
Conclusion
The mitotic index (cut-off 2 per 10 40x HPF) is of prognostic significance in IDHmut astrocytomas without HD CDKN2A/B. Therefore, the mitotic index may direct the therapeutic approach for patients with IDHmut astrocytomas with native CDKN2A/B status.
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