Global sensitivity analysis and Bayesian parameter inference for solute transport in porous media colonized by biofilms

The concept of dual flowing continuum is a promising approach for modeling solute transport in porous media that includes biofilm phases. The highly dispersed transit time distributions often generated by these media are taken into consideration by simply stipulating that advection-dispersion transport occurs through both the porous and the biofilm phases. Both phases are coupled but assigned with contrasting hydrodynamic properties. However, the dual flowing continuum suffers from intrinsic equifinality in the sense that the outlet solute concentration can be the result of several parameter sets of the two flowing phases. To assess the applicability of the dual flowing continuum, we investigate how the model behaves with respect to its parameters. For the purpose of this study, a Global Sensitivity Analysis (GSA) and a Statistical Calibration (SC) of model parameters are performed for two transport scenarios that differ by the strength of interaction between the flowing phases. The GSA is shown to be a valuable tool to understand how the complex system behaves. The results indicate that the rate of mass transfer between the two phases is a key parameter of the model behavior and influences the identifiability of the other parameters. For weak mass exchanges, the output concentration is mainly controlled by the velocity in the porous medium and by the porosity of both flowing phases. In the case of large mass exchanges, the kinetics of this exchange also controls the output concentration. The SC results show that transport with large mass exchange between the flowing phases is more likely affected by equifinality than transport with weak exchange. The SC also indicates that weakly sensitive parameters, such as the dispersion in each phase, can be accurately identified. Removing them from calibration procedures is not recommended because it might result in biased estimations of the highly sensitive parameters.

[Axonal neuropathy revealing pleural lymphoma as a long-term outcome of therapeutic pneumothorax]

Peripheral neuropathy is a rare presenting feature of malignant lymphoma, and commonly associated with diagnostic delay. We report a patient with axonal neuropathy revealing primary pleural lymphoma as a late outcome of pulmonary tuberculosis. A 72-year-old-man with a past medical history of pulmonary tuberculosis presented with a 5-month history of axonal neuropathy. The patient complained of chest pain, altered general status. Chest computed tomography (CT) showed pleural tumour invading the chest wall and CT-guided pleural biopsy revealed a B-cell lymphoma. Chemotherapy was not started in consideration of the poor performance status of the patient. Despite corticosteroids, the peripheral neuropathy worsened and the patient died 2 months after the diagnosis of lymphoma. To our knowledge, no previous case of peripheral neuropathy revealing pleural lymphoma has been reported. The diagnosis of lymphoma must be entertained in the presence of peripheral neuropathy of unknown aetiology. Neuropathy associated to lymphoma results from various mechanisms and is characterised by clinical polymorphism. Their prognosis depends on the mechanism of the neuropathy and the severity of the lymphoma.

[Family transmission of atopic organ manifestations and allergen sensitizing in 659 Tunisian families]

BACKGROUND

The atopic family transmission is the topic of many studies. In addition to the allergy total transmission, which is well established, it seems that atopic organ manifestations and their gravity are family transmitted. To our knowledge, very few authors studied the specific transmission of allergen sensitizing.

AIM

The aim of this paper is to study the specific family transmission of atopic organ manifestations and allergen sensitizing, in Tunisian families.

METHODS

659 supposed allergic Tunisian families are studied, which include 1494 patients, 444 parents and 1050 children, consulting for rhinitis and/or asthma. All patients were submitted to a family investigation and had an allergologic check including skin prick test.

RESULTS

We highlighted a transmission of the allergy according to the body between parents and their children. Asthma is more transmitted by the mother (p = 0.002) than by the father (p = 0.05). However, rhinitis is transmitted only by the father (p = 0.03). There is no significant concordance neither for asthma nor for rhinitis between children. Concerning the transmission of the allergenic sensitivity, our study doesn't show a statistically significant concordance between parents and children and between children.

CONCLUSION

These results confirm the atopic family transmission of the symptoms especially between parents and children. It doesn't seem to exist of hereditary factor concerning the sensitizing allergen.

[Soft tissue metastasis revealing an asymptomatic bronchial adenocarcinoma]

Skeletal muscle metastases from non-small-cell lung cancer are uncommon. We report a case of lung adenocarcinoma disclosed by metastatic dissemination to a forearm muscle. A 46-year-old man consulted for a painful mass of the right forearm. Ultrasonography and computed tomography revealed a heterogeneous collection in the forearm invading the cortex of the humerus. An excisional biopsy of the right forearm showed an infiltration of the muscle with metastatic adenocarcinoma. Immunohistochemical patterns suggested the pulmonary origin. Chest x-ray was normal. Bronchoscopy revealed an endobronchial mass that was confirmed by biopsy to be an adenocarcinoma. The lung tumor was staged T2N0M1. The patient has received local radiation therapy and chemotherapy. After eighteen months, the disease progressed but without local muscular recurrence. Skeletal muscle metastases from lung cancer are rare and although their prognosis is poor, local treatment may be worthwhile.

[Primary pulmonary angiosarcoma]

Pulmonary angiosarcoma is an uncommon vascular and usually secondary tumor. Only a few primary cases of pulmonary angiosarcoma have been described. We report a case of primary pulmonary angiosarcoma in an adult man who presented with hemoptysis. Chest x-ray film and chest CT showed a right para-cardiac opacity associated with diffuse alveolar consolidation of the right basal lobe. Right inferior lobectomy has been performed. Pulmonary angiosarcoma was diagnosed on histological and immuno-histochemical studies of the operative specimen. The primitive character was retained after ruling out all other tumor localizations. The clinical outcome was rapidly fatal. This observation is added to the other rare cases published of primitive pulmonary angiosarcoma. It confirms the poor prognosis and the extremely hemorrhagic nature of this tumor. Isolated necrotic parenchymatous mass was an original radiological pattern observed in this patient.

[Pseudo-tumoral aspergilloma]

Aspergilloma is the most common form of pulmonary aspergillosis, generally developing pre-existing lung cavities. Fiberoptic bronchoscopy is required in case of hemoptysis. We report the case of a 74-year-old man with pulmonary aspergilloma where fiberoptic bronchoscopy visualized mycetoma and cavitation. Visualization and biopsy of the fungus ball during fiberoptic bronchoscopy is rare.

[Basis and guidelines for empirical antibody therapy in the management of community-acquired pneumonia]

The choice of the antibiotic should be based on clinical, chest X-ray radiography and essentially microbiologic criteria. Incurrent practice treatment is more often empiric based on epidemiologic characteristics of the microbiologic agents and the particularities of each patient. A satisfactory approach requires, in addition, a perfect knowledge of different available antibiotics and the resistance of certain etiologic pathogens to these latters. because S. Pneumoniae is the most frequently encountered pathogen, B lactams and especially Penicillin G. and amoxicillin remain the most useful drugs prescribed for adults with risk factors. However, in advanced age patients and those with comorbidity, the spectrum should be enlarged and should include, besides S. Pneumoniae, H. influenzae and other Gram negative bacilli. When the pneumonia is more severe and has required hospitalization, the antimicrobial therapy must be immediate, multiple and large. The causal agent must be searched for desperately, so that the antimicrobial therapy can be adapted secondary to the results of the antibiogram.

[Diagnosis of an opacity at the lung base: intrathoracic kidney]

A 72-year-old patient was admitted for exploration of an opacity of the left base discovered fortuitously on a routine chest x-ray. Initial blood tests were normal. Fiberoptic bronchoscopy was normal. Computed tomography (CT) led to the diagnosis of a left kidney which had risen into a retro-cardiac position. Magnetic resonance imaging established the sub-diaphragmatic position of the kidney. Renal excretion was normal on intravenous urography. An ectopic kidney in an intrathoracic position is very uncommon and may raise a major challenge when visualized as a mediastinal or pulmonary opacity. Computed tomography or intravenous urography can provide the diagnosis and magnetic resonance imaging demonstrates its precise sub-diaphragmatic or supra-diaphragmatic position.