[Bilateral elastosis of the limbus]

We report of a case of bilateral limbus involvement by white lesions. A 72-year-old man was referred for bilateral lesions involving the inferior part of the corneal limbus. White excrescences associated with a vascular pannus were observed at biomicroscope examination. Histologic patterns showed degenerative fibroelastosis. Degenerative fibroelastosis can be observed at the inferior corneal limbus.

[Cervical adenitis caused by Mycobacterium kansasii: advantage of the INNO-LiPA V2 test in diagnosis of nontuberculous mycobacterial diseases]

Mycobacterium kansasii is one of the main mycobacterial species. Among the numerous subtypes, I and II subtypes are the only pathogens ones. A 56 years old woman has been under observation during her hospitalization for a cervical adenitis check-up; these one having been evolving for 2 months, without inflammatory syndrome. The failures of various antibiotics treatments lead one to withdraw some cervical ganglions whose histopathologic aspect reminds tuberculosis. These adenitis being isolated. An INH, rifampin, and ethambutol associated treatment is set up. After 2 weeks, the different cultures enable to isolated numerous photochromogenic colonies; a positive result is obtained with M. kansasii probe (Accuprobe). The identification is confirmed in 24 hours time with another molecular hybridation test (INNO-LiPA V2); the various specific probes of the different M. kansasii subtypes show it's not a I or II subtype (subtype IV by sequence analysis). This observation underlines the advantage and rapidity of the new diagnosis methods for nontuberculous mycobacterial diseases.

Activation of the PI3K/Akt pathway in neuroblastoma

9523

Background: Neuroblastoma is a pediatric malignant neurorectodermal tumor with still a poor survival in children over 1 year of age. In cancer, the PI3K/Akt pathway contributes to tumor aggressiveness (proliferation, metastasis). It is a major target for novel anti- cancer therapies. The objective was to study the activation of the PI3K/Akt pathway in NB. Methods: 101 patients (median age 2.5 years, range: 0–13) with a resected neuroblastoma (16 stage I; 7, II; 22, III; 48, IV and 8, IVS) were included. Tissue microarrays were constructed containing 101 primary tumors, 39 paired metastases and 56 paired normal tissues. Immunohistochemical staining was performed on sections using antibodies against PI3K, Akt and phosphoAkt (S-473). The expression of membrane receptors (EGFR, HER-2, VEGFR1, VEGFR2, PDGFRa, PDGFRβ, IGF1Rβ, TrkB), proteins directly interfering with AKT (PTEN, mTOR) and downstream proteins (phospho-p70S6 kinase, 4eBP1) was studied. The intensity was evaluated by a semi-quantitative score based on the percentage of positive cells. The Wilcoxon signed rank test was applied for the comparison of paired data and adjusted for multiple testing using the False Discovery Rate criterion. Spearman correlation values (rho) were used to compare the expression between genes in the primary tumors. Results: 60% of the tumors expressed PI3K, 80% AKT and 73% pAKT. In addition, phospho-p70S6 kinase and 4eBP1p were expressed in 95% and 85%. All these proteins had a higher expression in tumors as compared with paired normal tissues (fdr-adjusted p<0.001). Akt and pAkt showed a tendency for higher expression in metastases as compared to paired primary tumors (raw p<0.05 for both, but fdr-p=0.11 and fdr-p=0.17 respectively). While EGFR, IGF1Rβ, TrkB, PDGFRa and PDGFRβ were significantly more expressed in primary tumors as compared to normal tissues (fdr-p<0.05), only IGF1Rβ seemed more expressed in metastases (fdr-p=0.09). A significant positive correlation was found between pAkt and the following: VEGFR1, VEGFR2 and IGF1Rβ (rho>0.34, p<0.001), phospho-p70S6 kinase and mTOR(rho>0.26, p<0.01). Conclusions: The PI3K/Akt pathway is activated in neuroblastoma and could be an attractive target for novel therapies. In addition, the data suggested that VEGFR and IGF1R are preferentially committed to this pathway activation.

No significant financial relationships to disclose.

[Performances of the "Amplified Mycobacterium tuberculosis Direct Test" in respiratory and non-respiratory specimens]

From March 1998 to December 2004, 3641 specimens (2427 respiratory samples and 1214 non-respiratory samples) collected from 2079 patients, were tested using the "Gen-Probe Amplified Mycobacterium tuberculosis Direct Test" (AMTD). After decontamination procedure every sample was testing by AMTD and by culture on solid and liquid media. The "Gold-standard" was considered by the combination of culture results and clinical diagnosis. Respiratory tuberculosis was present in 9.7% (127 patients), and non-respiratory tuberculosis was present in 18.9% (170 patients, mostly originated from Africa). Among the 2427 respiratory samples (197 culture positive samples, 211 AMTD positive) 225 corresponded to tuberculosis; for the 1214 non-respiratory samples (184 culture positive samples, 213 AMTD positive) 231 corresponded to tuberculosis. After resolving the discordant results, the sensitivity, specificity, positive and negative predictive values were 93.8, 100, 100, 99.4% respectively for respiratory samples and 92.2, 99.9, 99.5, 98% for non respiratory samples.

Expression of erythropoietin and its receptor in neuroblastomas

9054

Background: Children with neuroblastomas (NB) may potentially benefit from treatment with recombinant human erythropoietin (Epo). Epo is a specific stimulator of erythropoiesis, acting via its specific receptor (EpoR). The aim of this study was to evaluate the expression of Epo and EpoR in NB and in normal tissues and their action in the proliferation of tumor cells. Methods: A tissue microarrays study was performed on 101 patients with NB from 3 hospitals (16 stage I; 7, II; 22, III; 48, IV and 8, IVS). Four blocks were constructed and contained 101 primary tumors, 39 paired metastases (35 lymph nodes), 56 paired control normal tissues and 6 cell lines of NB. Immunohistochemical staining was performed on sections using antibodies against Epo and EpoR. Immunostaining intensity was evaluated by a semi-quantitative score based on the percentage of positive cells. The wilcoxon signed rank test was applied for the comparison of paired data. For overall survival analysis, the expression was dichotomized at the median value and cox regression models were used stratified by hospital. An in vitro study of cell proliferation in presence of recombinant Epo was carried out with two of the 6 cell lines, one expressing EpoR, the other not. Results: Median follow-up was 64 months. The expression of EpoR was significantly higher in tumors than in paired control tissues (p<0.0001) but not for Epo (p=0.06). When restricted to the lymph nodes metastases, the level of expression of EpoR was significantly more expressed in the metastases than in primary tumors (p=0.02), contrary to Epo (p=0.99). Survival analysis showed that patients who expressed more EpoR had a statistically significant better overall survival than those who did not (p=0.03). Furthermore, the expression of EpoR was an independent prognostic factor from induction chemotherapy, tumor stage and age (p=0.02). No significant differences were found in Epo analyses. EpoR was expressed in only three cell lines and Epo not in any of them. In the in vitro study, recombinant Epo did not modify the proliferation of both cell lines. Conclusions: Epo and EpoR were expressed in NB but did not modify cells proliferation. The use of Epo in children with NB could be proposed but its benefit should be confirmed in a clinical trials.

No significant financial relationships to disclose.

Efficacy and Mechanism of Action of Chitosan Nanocapsules for Oral Peptide Delivery

PURPOSE

We have previously shown that high molecular weight (MW > 100 kDa) chitosan nanocapsules are efficient vehicles for improving the oral absorption of salmon calcitonin (sCT). In the present work, our objectives were, first, to investigate the influence of some formulation parameters on the efficacy of chitosan nanocapsules as carriers for the oral administration of sCT and, second, to elucidate the mechanism of interaction of chitosan nanocapsules with intestinal model cell lines.

METHODS

sCT-loaded chitosan nanocapsules were prepared by the solvent displacement technique. They were characterized for their size, zeta potential, and sCT loading. The ability of chitosan nanocapsules to enhance the oral absorption of sCT was investigated in rats by monitoring the serum calcium levels. Finally, the mechanism of interaction of chitosan nanocapsules with the Caco-2 cell model or in the coculture of Caco-2 with HT29-M6 cells was investigated by confocal fluorescence microscopy.

RESULTS

Chitosan nanocapsules presented a particle size in nanometer range, a positive surface charge, and an efficient encapsulation of sCT. Following oral administration to rats, all formulations of nanocapsules exhibited the ability to reduce calcemia levels; however, the intensity of the response varied depending on the formulation conditions. With regard to the mechanism of interaction of chitosan nanocapsules with cell culture, the xz images evidenced that chitosan nanocapsules interact and remain associated to the apical side of both model cell cultures. In addition, chitosan nanocapsules showed a preferable association to the mucus-secreting cells (HT29-M6).

CONCLUSIONS

Chitosan nanocapsules are able to enhance and prolong the intestinal absorption of sCT and this effect could be mainly ascribed to their mucoadhesive character and intimate interaction with the intestinal barrier.

Impact of cytopathologist expert on diagnosis and treatment of pancreatic lesions in current clinical practice. A series of 106 endoscopic ultrasound-guided fine needle aspirations

OBJECTIVES

To evaluate the role of a cytopathologist expert in interpreting difficult pancreatic endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) in terms of impact on diagnostic yield and therapy in current clinical practice.

METHODS

Retrospective study of 106 EUS-FNA performed between January 2002 and September 2004. Forty-seven cases of difficult interpretation by the local cytopathologist were mailed to an expert cytopathologist. The final diagnosis was established by histology obtained by either surgery (n=30), non-equivocal FNA (n=40) or core (n=8) biopsies, or by a mean follow-up of 14 months (n=28).

RESULTS

EUS-FNA involved 68 solid lesions (SL). Specimens collected were adequate in 63%. The overall sensitivity of EUS-FNA for the diagnosis of malignancy of SL was 88% versus 72% for local cytopathologist and 89% for expert. EUS-FNA with the reevaluation by expert of 39 SL gave a therapeutic impact in 47% of SL. Thirty-eight cystic lesions (CL) were evaluated. Specimens collected were adequate for cytology in 84% of cases and for biochemistry in 79%. The sensitivity of imaging+EUS-FNA+/-biochemistry for the diagnosis of a surgical CL was 58% with a therapeutic impact in 39.5%.

CONCLUSION

Pancreatic EUS-FNA is an easy technique for experienced endosonographers, which can be safely performed on an outpatient basis. The possibility of mailing difficult cases to an expert cytopathologist increases the diagnostic yield. In these circumstances, EUS-FNA has a therapeutic impact in current practice in nearly one out of two pancreatic lesions.

[Prenatal diagnosis of congenital mesoblastic nephroma. A case report]

Antenatal ultrasounds allow the detection of renal tumors, especially renal mesoblastic nephromas, but only the pathological analysis of the surgical specimen can confirm this diagnosis postnatally.

OBSERVATION

We report the prenatal discovery of a mesoblastic nephroma because of premature labour. Postnatal early surgery was decided because of possible complications in this premature infant. Histology revealed mesoblastic nephroma.

COMMENTS

We point out the diagnostic elements of congenital mesoblastic nephroma, especially in what is related to arterial hypertension and hypercalcemia, histology and cytogenetics.

Clinical evaluation of the gen-probe amplified mycobacterium tuberculosis direct test for rapid diagnosis of tuberculosis lymphadenitis

This prospective study evaluated the performance of the Amplified Mycobacterium Tuberculosis Direct Test (MTD) for the diagnosis of lymph node tuberculosis in Djibouti, Republic of Djibouti. Of 197 specimens sampled from 153 patients, 123 were from 95 tuberculous patients. The sensitivity and specificity of MTD were 93 and 100%, respectively. The sensitivity of culture was 89%.

Validation of a clinical guideline on prevention of venous thromboembolism in medical inpatients: a before-and-after study with systematic ultrasound examination

BACKGROUND

Clinical practice guidelines on prevention of venous thromboembolism in medical inpatients have been implemented in various settings, although few studies have assessed their impact on venous thromboembolism events.

OBJECTIVE

To determine whether the implementation of a locally developed guideline is followed by changes in the rate of deep vein thrombosis.

DESIGN

A before-and-after study consisting in two "1-day" cross-sectional studies.

SETTING

Thirteen adult medical wards in a teaching hospital in France.

SUBJECTS

All the patients hospitalized on the day of the cross-sectional study.

INTERVENTION

A clinical guideline integrating scientific evidence and data on target medical providers' practices was developed by a local expert panel and implemented through a multifaceted intervention.

MEASUREMENTS

Prevalence of deep vein thrombosis detected by systematic ultrasound examination.

RESULTS

The study included 338 patients in the preintervention sample and 340 in the postintervention sample. The prevalence of deep vein thrombosis decreased from 9.5% (95% CI, 6.6-13.1) in the preintervention sample to 3.2% (95% CI, 1.6-5.7) in the postintervention sample (P < 0.01). The decrease in the rate of thrombosis involved all deep veins of the lower limbs and remained significant after adjustment for risk factors (adjusted odds ratio = 0.47, 95% CI, 0.32-0.70). No additional cases of pulmonary embolism or deep vein thrombosis were reported either on the day of the study or in the following 2 days.

CONCLUSIONS

Active implementation of a clinical practice guideline directed at medical providers (doctors, nurses and physical therapists) can be followed by a significant decrease in prevalence of deep vein thrombosis.