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Patients with Mendelian susceptibility to mycobacterial diseases (MSMD) mainly suffer from Mycobacterium and Salmonella infections, which are due to mutations in genes controlling the interleukin (IL)-12/IL-23-dependent IFN-γ production. We performed a molecular diagnosis in two Mexican patients with persistent mycobacterial infections. Patients 1 (P1) and 2 (P2) from two unrelated, non-consanguineous families from two villages near Mexico City developed bacille Calmette-Guérin (BCG) disease secondary to vaccination; patients and their families were studied at the immunological level for production and response to IFN-γ. The β1 subunit of the IL-12 receptor (encoded by the IL12RB1 gene) was not expressed in cells from P1 or P2, or in two siblings of P1. Sequencing of the IL12RB1 gene showed the same point mutation 1791+2 T>G, homozygous in patients and heterozygous in parents. P1 and P2 died at the ages of 4 and 16 years, respectively, with disseminated and uncontrolled BCG disease and with Candida albicans infections in spite of multiple anti-mycobacterial drug treatments. One of P2's siblings also died following disseminated mycobacterial infection secondary to BCG vaccination. These are the first cases in Mexico of patients with BCG disease traced to a mutation in the IL12RB1 gene, with a fatal outcome. Doctors must be alert to the adverse reactions to BCG vaccination and to persistent Mycobacterium infections, and in such cases should investigate possible mutations in the genes of the IL-12/IL-23-IFN-γ axis., (Copyright © 2010 International Society for Infectious Diseases. All rights reserved.)

Mycobacterium bovis BCG is the only available vaccine against tuberculosis. Reasons for why diverse BCG substrains induce different levels of protection in clinical trials remain unclear. The aim of this study was to compare the effectiveness of 10 BCG substrains in a mouse model of pulmonary tuberculosis. BALB/c mice were subcutaneously vaccinated and 2 months later were challenged with Mycobacterium tuberculosis H37Rv by intratracheal injection. Two and 4 months after challenge, delayed-type hypersensitivity (DTH) response, lung tissue affected by pneumonia, CFU, T-cell counts, and cytokine expression (interleukin-2 [IL-2], IL-4, IL-10, and gamma interferon) were determined. A differential protective effect of the diverse BCG substrains was found. BCG Phipps led to the largest and most persistent reduction of CFU counts and of the area of pneumonia at 2 and 4 months after challenge. This protection was accompanied by reduced IL-10-producing T cells. Contemporary BCG substrains induce a wide range of protection in this animal model. These data can help in the selection of the best vaccine for human immunization and for the development of novel recombinant BCG-based vaccine.

Background: The ESAT-6 antigen from Mycobacterium tuberculosis evokes a protective immune response in murine models and is widely recognized by tuberculosis patients (TB) and healthy household contacts (HHC). However, little is known about human immune response to this antigen in populations from areas of high endemicity. This study aimed to determine the capacity of T-cells from a group of TB patients and HHC for cell proliferation and production of cytokines type Th1 or Th2 (IL-4, IL-10, and IFN-gamma) and to identify total IgG reactivity to the recombinant protein rESAT-6 and five overlapping synthetic peptides as well as to r38 kDa and two peptides., Methods: T-cells from nine TB patients and nine HHC were stimulated with rESAT-6 and five overlapping synthetic peptides, previously selected from a set of 21 peptides and each of 16 amino acids in length (P1, P4, P6, P8, and P20). Similar experiments were carried out with r38 kDa and two peptides of 20 amino acids in length (38G and 38K). Cytokines in supernatants and total IgG from serum were determined by ELISA., Results: Stimulation index (SI) was highest in HHC to rESAT-6 and peptides P1, P8, and P20. Differences in response to 38 kDa and 38G peptide between TB patients and HHC were not demonstrated. Cytokines from T-cell cultures were tested with a resulting SI=3.0. IFN-gamma was produced predominantly in HHC to rESAT-6, P8, and P20, while in TB patients production of IL-10 was detected in relation to r38 kDa. IL-4 was detected in minimal amounts in both groups. IgG from TB patients was predominantly recognized in connection with rESAT-6 and the P4 peptide, with an important response against r38 kDa detected in HHC., Conclusions: ESAT-6 recognition by HHC could indicate that these responses represent possible early-stage infections.

Tuberculosis is a public health problem. If the current trends continue, is expected to arrive to 10.2 million of new cases in 2005. There are three studies accomplished in 1995 in Mexican patients. The results show important difficulty in the application and the follow-up of the program of control of the tuberculosis, what has caused accumulation of chronic cases, moderate rate of primary resistance and alarming levels of primary and secondary multiresistance (23%). Mechanism of protective immunity against mycobacterium tuberculosis (MTB) in humans have not been clarified. Different subpopulations of lymphocytes CD4, CD8 and other populations as well as macrophages, and monocytes, have an important role. In industrialized countries, the managing of the MDRTB is based on the use of individualized treatments with second line drugs according to susceptibility test, however the foregoing has not been possible to apply it middle or low income countries. WHO has launches the initiative "DOTS plus" that consist in the administration of a standarized regimen on the basis of epidemiology of resistance in the country or region.

Background: Several opportunistic intraocular infections have been described in patients with the human immunodeficiency virus, among them infections caused by Mycobacterium tuberculosis. In most cases, the diagnosis is based on clinical findings. Recent reports have described the usefulness of polymerase chain reaction techniques in the diagnosis of bacterial infections., Methods: The authors observed a 29-year-old woman with acquired immune deficiency syndrome in whom unilateral chorioretinitis developed. The chorioretinitis appeared after cessation of treatment for pulmonary tuberculosis. We obtained aqueous humor by paracentesis and tested it by polymerase chain reaction to detect M. tuberculosis DNA., Results: The polymerase chain reaction of the aqueous humor was positive for M. tuberculosis DNA., Conclusion: Polymerase chain reaction was useful in identifying M. tuberculosis in aqueous from a patient with chorioretinitis, pulmonary tuberculosis, and acquired immune deficiency syndrome.

Tuberculosis and human immunodeficiency virus (HIV) infection are two important linked public health problems in the world of today. Tuberculosis in HIV infected patients is frequently atypical in its clinical and radiological findings and commonly has an extrapulmonary dissemination. Atypical mycobacteriosis have also been reported in patients with HIV infection. We review here all the patients admitted from 1986 to 1991 with definitive diagnosis of tuberculosis and HIV infection at the National Institute of Respiratory Diseases in Mexico City. Out of 220 patients with HIV infection and pulmonary complications, 19 had proven tuberculosis. Their mean age was 34 +/- 8 years and seven were homosexual males. In 16 patients (84%), respiratory symptoms (cough with sputum) and fever were the first manifestations of the HIV infection. Only two patients had the typical cavitary lesions but also coexisting with miliary tuberculosis. The rest had several types of non cavitated pulmonary opacities or other thoracic or pleural alterations. Eleven patients (58%) had, in addition, extrapulmonary tuberculosis. Mycobacterium tuberculosis was cultured in 11 of 12 patients but no atypical mycobacteria were isolated. Only seven of the 19 patients completed at least six months of treatment and two of them relapsed. Three patients died in their first admission; the rest were lost in the follow up. Our results show that the clinical features of tuberculosis associated to HIV infection are similar to those described in other countries.

Measles pneumonia is the most frequent complications associated with mortality in this infection. There are two types, one corresponds to the giant-cells pneumonia and the other one to lung superinfection after measles infection. The first one has been occurred in immunosuppressed patients, without rash. We reported a measles pneumonia case in a previously healthy adolescent girl who had a fatal pneumonia by giant cells demonstrated by open lung biopsy. The review of the literature showed that this is very unusual in normal population.

We describe a case of polimicrobial endocarditis in a patient with congenital aortic stenosis and end-stage renal failure in treatment with steroids and chronic haemodialisis. The blood culture grew e.coli, enterobacter sp, and s.epidermidis. Only a few papers in the literature have been devoted to this entity. Its frequency seems to be progressively higher. The present case is a good example to talk about the predisponent factors. The review of literature has shown that the occurrence of this entity is specially high among addicts, the most frequent bacteria are s.aureus, streptococci and pseudomonas and the mortality can be as high as 80%.