[Silicoproteinosis: A specific clinical and radiological entity].

Rev Mal Respir. 2012 Nov;29(9):1132-6

Authors: Racil H, Ben Salem N, Chaouch N, Ismail O, Cheikh Rouhou S, Hantous S, Chabbou A

Abstract
INTRODUCTION: Silicoproteinosis is a rare disease, which can cause the rapid onset of respiratory failure following massive exposure to silica dust.
CASE REPORT: A 25-year-old patient presented with altered state and dyspnea. The diagnosis of military pulmonary tuberculosis was first considered and antituberculous treatment was started. The diagnosis was reconsidered due to a lack of improvement and the discovery of an 18-month history of exposure to silica. The patient had stopped work 6 months prior to hospitalization. High-resolution CT showed air space condensation associated to centrilobular nodules throughout the lungs and multiple mediastinal lymph nodes, suggesting sarcoidosis. Bronchoalveolar lavage (BAL) suggested the diagnosis of lipoproteinosis. Because of discordance between the bacteriological, radiological and the BAL results, a surgical lung biopsy was performed which led to the diagnoses of a secondary lipoproteinosis. The diagnosis of silicoproteinosis was then considered. Over a one-year follow up, the patient's respiratory failure has progressed markedly despite treatment with corticosteroids.
CONCLUSION: Silicoproteinosis is a distinct pathological entity, the diagnosis of which depends on clinical and radiological features as well as BAL findings, which may avoid the need for more invasive investigations.

PMID: 23200588 [PubMed - in process]

Modelling HIV and MTB Co-Infection Including Combined Treatment Strategies.

PLoS One. 2012;7(11):e49492

Authors: Ramkissoon S, Mwambi HG, Matthews AP

Abstract
A new host-pathogen model is described that simulates HIV-MTB co-infection and treatment, with the objective of testing treatment strategies. The model includes CD4+ and CD8+ T cells, resting and activated macrophages, HIV and Mycobacterium tuberculosis (MTB). For TB presentation at various stages of HIV disease in a co-infected individual, combined treatment strategies were tested with different relative timings of treatment for each infection. The stages were early HIV disease, late HIV disease and AIDS. The main strategies were TB treatment followed by anti-retroviral therapy (ART) after delays of 15 days, 2 months and 6 months. ART followed by TB treatment was an additional strategy that was tested. Treatment was simulated with and without drug interaction. Simulation results were that TB treatment first followed by ART after a stage-dependent delay has the best outcome. During early HIV disease a 6 month delay is acceptable. During late HIV disease, a 2 month delay is best. During AIDS it is better to start ART after 15 days. However, drug interaction works against the benefits of early ART. These results agree with expert reviews and clinical trials.

PMID: 23209581 [PubMed - in process]

Contacts of infectious tuberculosis patients: monitor those at highest risk of developing tuberculosis.

Prescrire Int. 2012 Nov;21(132):270-3, 275

Authors:

Abstract
It is essential to identify and treat contacts of tuberculosis patients with active disease. Persons exposed through close, prolonged or frequent contact may develop tuberculosis, usually within two years following exposure. What is the harm-benefit balance of tuberculosis prophylaxis in contacts at risk? To answer this question, we conducted a review of the literature, using the standard Prescrire methodology. Standard prophylaxis for pulmonary tuberculosis consists of isoniazid monotherapy for 6 to 12 months.This regimen has been tested in randomised placebo-controlled trials involving tens of thousands of persons with a positive tuberculin skin test (TST). Pulmonary tuberculosis occurred in 0.6% of patients in the isoniazid groups versus 1.7% in the placebo groups, after a follow-up of at least 2 years. However, isoniazid can cause severe hepatic disorders and numerous drug interactions. Rifampicin monotherapy was shown to be effective in only one placebo-controlled trial in patients with silicosis, who have a very high risk of developing tuberculosis. Rifampicin also carries a high risk of drug interactions but is less hepatotoxic than isoniazid. A 3-month course of the isoniazid+ rifampicin combination had a similar harm-benefit balance as a 6- or 9-month course of isoniazid monotherapy. The rifampicin + pyrazinamide combination is no more effective than isoniazid monotherapy but has more hepatic adverse effects. British guidelines issued in 2011 recommend treatment for contacts who have signs of latent tuberculosis infection, based mainly on a positive TST or gamma interferon release assay, and are at high risk of developing active tuberculosis. patients aged at least 2 years who are strongly suspected of having latent tuberculosis infection: either tuberculosis treatment, or chest radiography 3 and 12 months after initial diagnosis. In practice, contacts of infectious patients have a low risk of developing clinical tuberculosis.Treatment reduces the risk of tuberculosis but exposes a large number of persons to numerous, sometimes serious, adverse effects. Watchful waiting for 2 years, without treatment, is often the best option.

PMID: 23210263 [PubMed - in process]

Compassionate use of and expanded access to new drugs for drug-resistant tuberculosis [Review article].

Int J Tuberc Lung Dis. 2012 Dec 4;

Authors: Jr CR, Haxaire-Theeuwes M, Wingfield C, McNeeley D, Pyne-Mercier L, Keshavjee S, Varaine F, Lienhardt C, Resist-Tb FR, Access TC, Workgroup A

Abstract
Several new classes of anti-tuberculosis agents are likely to become available in the coming decade. Ensuring prompt access to these drugs for patients without other treatment options is an important medical and public health issue. This article reviews the current state of 'compassionate use' and 'expanded access' programs for these new drugs, and identifies several shortcomings that will limit patient access to the drugs. A series of five steps is outlined that will need to be taken by national health bodies, international agencies and non-governmental organizations to prevent undue delays in access to new tuberculosis drugs for patients who could benefit from them. Following these steps can ensure that patients will be able to benefit from access to these drugs, while minimizing the risk of emergence of resistance to the drug.

PMID: 23211610 [PubMed - as supplied by publisher]