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Our institution has performed microbiological diagnosis of Tropheryma whipplei since 2001, initially with a PCR targeting 16S rRNA before the development of a quantitative PCR in 2012. Here we report the clinical characteristics of a cohort of patients suffering from Whipple disease (WD) and evaluate the impact of these molecular techniques. Patients with a positive PCR for T. whipplei between 2001 and 2016 were retrospectively collected from microbiological databases. Two infectious diseases specialists reviewed their medical records and classified them as definite WD, probable WD or carriage of T. whipplei without disease. A total of 1153 samples were tested for T. whipplei; 76 samples taken from 36 patients were positive. Fifteen were considered as presenting a definite WD, seven as a probable WD and 14 as carriers. Median age was 56.4 years (extremes, 6.6–76.1). Median time from symptoms to diagnosis was 3 years (2.5 months to 13.3 years). About 60% were immunosuppressed. The most frequent clinical presentations were joint pain (16/22), weight loss (15/22) and/or digestive tract disorder (15/22); 41% had neurological manifestations, 32% pulmonary involvement and 32% lymphadenopathies. Bacterial load in faeces or saliva were 88 425 copies/mL (IQR 6175-292 725) in definite and probable WD and 311 copies/mL (IQR 253–2090) in carriers, respectively. We observed a 90% PPV above 32 200 copies/mL in faeces. WD is a chronic multisystemic disease with frequent pulmonary involvement. Underlying immunodeficiency is commonly observed leading to more complex clinical presentation. Positive T. whipplei PCR in both stool and saliva has a high positive predictive value. Moreover, patients with WD present higher bacterial load in faeces with a threshold of >32 200 copies/mL predicting ongoing infection.  相似文献   
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The aim of this study is to evaluate the prevalence, determinants and prognostic value of pain at diagnosis in patients with desmoid-type fibromatosis (DF). We selected patients from the ALTITUDES cohort (NCT02867033), managed by surgery, active surveillance or systemic treatments, with pain assessment at diagnosis. Patients were invited to fill QLQ-C30 questionnaire and Hospital Anxiety Depression Scale. Determinants were identified using logistic models. Prognostic value on event-free survival (EFS) was evaluated using the Cox model. Overall, 382 patients were included in the current study (median age: 40.2 years; 117 men). The prevalence of pain was 36%, without significant difference according to first-line treatment (P = .18). In the multivariate analysis, pain was significantly associated with tumor size >50 mm (P = .013) and tumor site (P < .001); pain was more frequent in the neck and shoulder locations (odds ratio: 3.05 [1.27-7.29]). Pain at baseline was significantly associated with poor quality of life (P < .001), depression (P = .02), lower performance status (P = .03) and functional impairment (P = .001); we also observed a nonsignificant association with anxiety (P = .10). In the univariate analysis, baseline pain was associated with poor EFS; the 3-year EFS was 54% in patients with pain compared to 72% in those without pain. After adjustment for sex, age, size and line of treatment, pain was still associated with poor EFS (hazard ratio: 1.82 [1.23-2.68], P = .003). One third of recently diagnosed patients with DF experienced pain, especially those with larger tumors and neck/shoulder locations. Pain was associated with unfavorable EFS after adjustment for the confounders.  相似文献   
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Purpose

The objective was the development of a whole-body physiologically-based pharmacokinetic (WB-PBPK) model for colistin, and its prodrug colistimethate sodium (CMS), in pigs to explore their tissue distribution, especially in kidneys.

Methods

Plasma and tissue concentrations of CMS and colistin were measured after systemic administrations of different dosing regimens of CMS in pigs. The WB-PBPK model was developed based on these data according to a non-linear mixed effect approach and using NONMEM software. A detailed sub-model was implemented for kidneys to handle the complex disposition of CMS and colistin within this organ.

Results

The WB-PBPK model well captured the kinetic profiles of CMS and colistin in plasma. In kidneys, an accumulation and slow elimination of colistin were observed and well described by the model. Kidneys seemed to have a major role in the elimination processes, through tubular secretion of CMS and intracellular degradation of colistin. Lastly, to illustrate the usefulness of the PBPK model, an estimation of the withdrawal periods after veterinary use of CMS in pigs was made.

Conclusions

The WB-PBPK model gives an insight into the renal distribution and elimination of CMS and colistin in pigs; it may be further developed to explore the colistin induced-nephrotoxicity in humans.
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