• Yogarabindranath Swarna Nantha added an answer:
    What do you conclude when you have prevalence of latent TB infection (LTBI) amongst diabetics that's close to the prevalence of LTBI in the community?

    If the methodology of the study is sound, can you just conclude by saying that being diabetic does not confer an extra risk of being predisposed to latent TB infection (in contrast to having tuberculosis)? Or does this mean that the levels of latent TB in the community is overwhelmingly large that it is almost similar to levels in diabetics?

    Yogarabindranath Swarna Nantha · Ministry of Health Malaysia

    Hi Shawn,

     Thanks for your imput. Yes, each patients who tested positive for Mantoux were subjected to chest x-rays.


  • Umamaheshwari S added an answer:
    Can ESR predict TB?

    On infections ESR gets elevated, but correlating with clinical conditions in TB, can ESR serve to predict TB especially in HIV positive and sputum smears are negative/ sputum nonproductive?

    Umamaheshwari S · University of Mysore

    Elevated ESR though not a specific test for TB, few TB studies show elevated ESR. obviously correlating with clinical symptoms and elevated ESR can serve as one of the tool to suspec and diagnose especially in smear negative TB cases

  • Umamaheshwari S added an answer:
    Wont Mycobacteria isolated from stool specimen confer TB infection?

    Does isolate from a stool sample prove a person is infected with TB?

    Umamaheshwari S · University of Mysore

    I do agree with Mr Werner. Species diagnosis is must to decide treatment

  • Timothy Mark Doherty added an answer:
    Where can I find a paper which shows that zoonotic tuberculosis (M bovis) is not transmissible among immunocompetent humans?

    Recently I read a paper which authors state that zoonotic tuberculosis (M. bovis) is not transmitted among immunocompetent humans.
    Now, when I search, I can't locate it. Can anyone help me?

    Timothy Mark Doherty · GlaxoSmithKline plc.

    Edit: I should also note that if one really wanted to use the very old literature in this case, then you can easily find reports of human infection with M. bovis attributed to consumption of milk. The article "Reports on bovine tuberculosis and public health. Salmon, D. E. USDA, 1904." lists well over a dozen cases of infection, including some oddball ones such as use of cream (from milk from a cow with tuberculous mastitis) to treat eczema, leading to percutaneous tuberculosis infection, as well as more conventional infections derived from drinking milk from a cow with tuberculous mastitis - including one where 12 girls at a boarding school contracted abdominal tuberculosis (5 of whom died). On investigation of that case, it was found that the cow supplying milk for the girls had tuberculous mastitis. The girls had no other known risk factors and were not in contact with the animal directly, leaving the milk as the only known source of infection.  You can find this report in fascimile online, and there are literally hundreds of similar reports from the first quarter of the 20th century.

    The trouble with using these ancient reports indicating infection is exactly the same as with the ancient reports you referred to above: the science was still evolving and back in the early 20th century they were still investigating questions about host range, transmission and susceptibility that were conclusively settled decades ago. The scientists of the time were smart enough to know how limited their knowledge was. Salmon wrote of the case reports of infection via milk:

    "These are examples of clinical evidence which might be greatly extended, but all are, of course, open to the objection that we do not know absolutely that the disease was caused by the bovine bacillus. However, the occurrence of abdominal tuberculosis soon after the use of milk from tuberculous cows is a coincidence which justifies us in accepting the cases as strong circumstantial evidence, not of themselves demonstrating the communicability of bovine tuberculosis, but, taken with other evidence, making a case which it is difficult to contest."

     In the 21st century, however, we have no such problems and the recent outbreaks in the US already cited not only were proven by typing to be M. bovis, but were linked to the same strains in contaminated unpasteurised dairy products and the strains themselves proven by spoligotyping to overwhelmingly be those circulating in cattle not in the local region (where M bovis infection is rare), but in Mexico (see, for example, Rodwell et al. Tracing the origins of Mycobacterium bovis tuberculosis in humans in the USA to cattle in Mexico using spoligotyping. IJID.  2010, 14: e129–e135. In this case, transmission by direct contact with cattle can be clearly ruled out and a direct line of infection via contaminated dairy produce remains the most likely route of infection (indeed, the only plausible route, in many cases).

    Given the clear evidence available from recent outbreak investigations, why would one resort to musty, century-old studies with weaknesses acknowledged even at the time?

  • Nouhoum Bouare added an answer:
    Any advice on tuberculosis screening in HIV-infected patients?

    From a public health standpoint , what  current or future alternatives would you recommend for better tuberculosis screening in HIV-infected patients?

    Nouhoum Bouare · University of Liège

    To manage efficently HIV infected patient, they should be tested for three tests: tuberculosis (baciloscopy), HBV (HBsAg) and HCV (Ab/Ag EIA test).

  • Vipin Katoch added an answer:
    Why I can not find sufficient and well macrophage after PBMCS culture?

    I have a research about phagocytosis activity of macrophage from cell culture of PBMCS from children contact with adult tuberculosis, but I cannot found good macrophage from my culture. I don't know waht happen. Any suggest from other researcher that have more experiend with this procedure?

    Vipin Katoch · Deputy Director, (Animal Health / Breeding) Kangra

    The monocytes adhere very well to glass,plastic surface. Incubation of PBMCs for 2hrs  should generally be sufficient for the monocytes to adhere. Please verify that you are not using siliconised culture ware. The viability reduces with the time post collection of blood. Generally 5x106to 1x107  PBMCs  are required to set up a good culture.  THe type of medium and concentration of FCS also decides the number and viability of cells.

  • Gehendra Mahara added an answer:
    Can anyone explain to me how to do a study about PM 2.5 and tuberculosis infection?

    Can anyone explain me that how to do a study about PM 2.5 and tuberculosis infection?

    Gehendra Mahara · Capital Medical University

    Thank you Saileela Kondapaneni madam.

  • Tefera B Agizew added an answer:
    What is a suitable way we can eliminate tuberculosis?

    Do you have suggestions/ideas which can change the statistics of TB in the world?

    Tefera B Agizew · U.S. Department of Health and Human Services

    In my opinion resource and political commitment seem to be the two major key points from the European experience and even from the USA. In the USA we have seen TB resurgence after control and again when resource boosted the TB situation went down hill again. These are clear indications to the road to elimination o TB. All other things, education, awareness, living conditions, application of available best drugs and diagnostics are also key factors. However, controlling or improving these factors depends where you are - low, middle or high income countries. With all these the journey is long but possible.  

  • Jamunanantha Sivanathan added an answer:
    Mycobacteria DNA extraction directly from blood?
    Currently there are some kits allow the extraction of Mycobacteria DNA directly from sputum samples and tissue biopies. Does anyone know any similar fast and simple method for extraction from blood samples?
    Jamunanantha Sivanathan · chest clinic jaffna

    Mycobacteria  is an intracellular pathogen and not in the blood circulation.So it is not the correct question.

  • Nagendra Babu Mennuru added an answer:
    Does anyone know Research centers in India that carry out assays for tuberculosis for screening of new compounds?

    Does anyone know any commercial or non-commercial research facilities within India (preferably in Chennai, Hyderabad, Bangalore and rest of India) to perform screening assays for Tuberculosis on new compounds? Added to this I require the results within 15-20 days?

    Nagendra Babu Mennuru · Annamacharya College of Pharmacy

    Dr. Sonali Dalwadi:

    Thank you for the information, I will check these sources....

    Dr. Mayur:

    Thanks for the details, yes, I had contacted through mail regarding the possibility, reply need to be expected....

    Thanks & Regards,

    Nagendra Babu M.

  • Leena Menghaney added an answer:
    Does anyone have any experience in giving Delamanid and Bedaquiline together for the treatment of XDR Tuberculosis?

    I have very limited therapeutic options treating a patient with extensively Drug resistant TB. However there is no evidence in the literature of the association of these two drugs in a regimen. They are now commercially available however there is little consensus to adding them together given the paucity of safety data. Has anyone managed to give the two drugs together, where there any adverse events and/or increases in QTc?

    Leena Menghaney · Doctors Without Borders

    you should contact Dr. Homa Mansoor at the MSF Mumbai DR TB Clinic in Mumbai on this very interesting question. Her email is

  • Brian Weinrick added an answer:
    Does M. smegmatis have a homologous enzyme of HsaAB?

    In M. tuberculosis, cholesterol catabolism goes through a complex process. The ring opening process involves production of 3-hydroxy-9,10-seconandrost-1,3,5 (10)-triene-9,17-dione (3-HSA). A flavin-dependent monooxygenase hydroxylates 3-HSA to 3,4-DHSA. I wanted to find out whether M. smegmatis contains a homologue that carries out the hydroxylation reaction. If yes, what is the name of the enzyme and the gene encoding it?

    Brian Weinrick · Albert Einstein College of Medicine

    Tuberculist shows orthologs MSMEG_6038 and MSMEG_6035 for hsaA and hsaB, respectively:

  • Antonio Cantó added an answer:
    Can anybody tell me how tuberculosis might lead to lung cancer?

    There are so many changes including physiological,histological,biochemical and immunological changes associated with secondary TB. So what is the mechanism that leads to tumour of lung sometimes?

    Antonio Cantó · Clinica Quiron de Valencia

    Solo conozco el " carcinoma de cicatriz" en tuberculosis ya curadas.

    De acuerdo con los Drs Newhouse y Braenbtll.Saludos

  • Yogarabindranath Swarna Nantha added an answer:
    Can eGFR calculation using S.Creatinine among patients with TB &DM be accurate and is there any other method?

    If S.Creatinine is being used for calculating eGFR , in patients with DM what are the essential parameters  we have to look into.

    Yogarabindranath Swarna Nantha · Ministry of Health Malaysia

    Based on my experience (and current research work on LTBI and DM), I feel that MDRD (eGFR) is a suitable measure of kidney function. Having said that, I often take the average/mean of three different reading in a span of 2 years to avoid any inaccuracies in relation to normal biological variation.

    Hope this helps.


  • Lawrence Broxmeyer, MD added an answer:
    Where can I find age-structured incidence data for AIDS defining opportunistic infections starting from before AIDS epidemic in Sub-Saharan Africa?

    I am interesting in finding prevalence/incidence rates of specific opportunistic infections of young age groups (not adult) from before and after the start of the AIDS epidemic (~1980). 

    In particular I am looking for trends in: Tuberculosis, Cryptosporidium, and Non-Typhi Salmonella. 

    Does anyone know if such data exists and where I can find it? I would want to look in an area where HIV/AIDS is widespread, so somewhere in Sub-Saharan Africa would be ideal (or the whole region). 

    Lawrence Broxmeyer, MD · NY Insitute of Med Research

    "Where can I find age-structured incidence data for AIDS defining opportunistic infections starting from before AIDS epidemic in Sub-Saharan Africa?
    I am interesting in finding prevalence/incidence rates of specific opportunistic infections of young age groups (not adult) from before and after the start of the AIDS epidemic (~1980). 

    In particular I am looking for trends in: Tuberculosis, Cryptosporidium, and Non-Typhi Salmonella. "


    Very well. But why go to WHO? Perhaps you should start by seeking statistical data and maps for Tuberculosis and M. avium, which still are the leading causes of infectious death in HIV/AIDS. Before such typical and atypical mycobacteria were proclaimed "AIDS-defining illness" by the likes of WHO, you will notice that they admitted that tubercular disease killed close to 3 million people a year. Then since it has magically  "defined" AIDS -  it is now purported that tubercular disease kills merely a million and a quarter annually. Interesting math.

  • Tony Ete added an answer:
    How can I manage patients with total resistance for anti TB medications?

    There is no convincing guidelines on how I can approach total drug resistance accordingly. So how do we manage patients who are resistant to medication for XDR - TB?

    Tony Ete · North Eastern Indira Gandhi Regional Institute of Health & Medical Sciences

    Excluding your list of medications there are many drugs known to be effective in Tuberculosis including PAS,Linezolid,Imipenem plus cilastatin,Clofazimine,Amoxicillin and clavulanate,Clarithromycin.What about them?

  • Mani Sankar added an answer:
    What is the difference in Mycobateria growth in flat vs v (conical) - well shaped 96 - well microtiter plates?
    I have been determining MICs for M. tuberculosis using 96 - well microtiter plates, flat well shape. After five days, I confirm positive growth by adding alamar blue to my controls.

    Recently I ran into a supplier issue and I could not obtain plates with flat wells but had to revert to using V or conical shape wells. After five days of incubation, I add alamar blue. There is difference in the color change. In the flat wells, color change after five days is a distinctive pink, whereas in the v or conical shape wells, it's a purple/violet.

    All conditions remain exactly the same between the two.

    What could cause this issue? Is it a surface area problem? Could it be that cells sink to the bottom in v or conical shaped wells and are not in entire contact with the alamar blue?

    Has anybody else observed such an issue?
    Mani Sankar · All India Institute of Medical Sciences

    Dear Shane

    I have not performed alamar blue testing using 'V' bottom plates. But the possible reason may be the surface area difference between the flat and V bottom plates. In V bottom plates the cells could settle in the bottom and could produce a high intensity coloring. whereas in the flat bottom plates the cells are dispersed even the coloring would be of less intensity. I recommend you to continue with the 'Flat bottom' plates instead of V bottom which will seriously affect your results and OD values.

    Best regards

  • Rajendra Takhar added an answer:
    What are the organs in human body never reported to be involved in tuberculosis?

    Is it thyroid, Pancreas, heart ?Is it absolute? What are the remaining organs not involved?Any data on this available or not? 

    Rajendra Takhar · Rajasthan University of Health Sciences

    "TB can present like anything except pregnancy".  Well said.....

  • Shaopeng Yuan added an answer:
    Is 18s rRNA is right option for internal Control in RT PCR?

    I am working on RT PCR for Tuberculosis. I want internal amplification control for my RT PCR. 18s rRNA is one of the house keeping gene. Can we use the same for PCR internal control ? Can it also clear the state of DNA isolation form Sputum?

    Shaopeng Yuan · The Rockefeller University

    DNA from sputum contains mix population of cells and bacterias. I would recommend to use a combination of 3-5 house keeping genes to take geometric mean to use as normalization factor. You can select about 10 potential HK genes and then use GeNorm       method to select the top three HK genes.

  • Mace M Schuurmans added an answer:
    Is bronchoscopy always abnormal or not in Endobronchial Tuberculosis?

    I've seen an italian man, HIV+ on treatment, who had a history of fever, cough, thoracic pain, some episodes of hemoptysis (I saw one of them, a big one, so he is credible).

    We performed a CT scan (infiltrate in the upper right lobe tree-in-bud like) and a bronchoscopy (normal, except for a sign of previous bleeding in correspondence of the CT lesion) with BAL.

    What do you think about the diagnosis? Would you start an anti-TB therapy ex-juvantibus? 

    Mace M Schuurmans · University Hospital Zurich

    In haemoptysis do not forget to sample the expectorated blood as "sputum" for detection of AFB and culture. It comes from the site of potential infection and helps in the diagnosis. 

  • Rajendra Angara added an answer:
    Is there any mycobacterial protein which is non toxic when over expressed in M.tuberculosis but toxic when over expressed in M.smegmatis?

    Hi, I am characterizing the transcriptional regulator of Mycobacteirum tuberculosis .

    Because we don't have facility for M.tuberculosis culture, I am trying to over express (using PVV16 which has Hsp60 promoter) it in M.smegmatis. but I never got colonies though the clone and vector back bone are fine. So I thought over expression might be toxic to M.smegmatis. so to check its toxicity I did frame shift mutations and found its over expression is not lethal.

    However for the same protein Chip-seq data available in MTB Network Portal. By going through their publication in NAR, I realised they over expressed corresponding transcription factors in M.tuberculosis using Tet-inducible system and did Chip-seq analysis.

    My question is, is over expression of my protein not toxic to M.tuberculosis but toxic to M.smegmatis or am I simply doing something wrong?

    How can I get a over expression strain of M.smegmatis?

    Rajendra Angara · The Centre for DNA Fingerprinting and Diagnostics

    Dear @Jan van Ooyen , thank you for your kind reply.

    using Acetamide inducible promoter, i am able to over express the protein.

  • Haradhan Kumar Mohajan added an answer:
    Can anyone help with XDR-TB treatment?
    I want to investigate a rather new chemotherapy with well-known medications for XDR-TB. Unfortunately, there are no facilities and safety to conduct the experiment on TB-infected cell lines here in Iran. Please help me provide the way to do this work.
    Haradhan Kumar Mohajan · Premier University

    I have a paper on TB and we can share our opinions. I am not giving you solution to treat XDR TB.

  • Helmi Sulaiman added an answer:
    Does negative IGRA predicts TB negativity?

    Positive IGRA might suggest infection be it latent or active. But is the relationship true in another direction? Is there any data out there to help me answering the question?

    Helmi Sulaiman · University of Malaya

    I rather not use this expensive test actually to test active TB... not TST too 

  • Yadav K S added an answer:
    Is there any method to detect TB directly using Blood?

    In majority of the cases sputum,body fluids correlating to symptoms TB is diagnosed but can blood samples be used directly?and/or is lysing agent required preferentially?

    Yadav K S · Padmashree Dr. D.Y. Patil University

    There are many methods for detecting TB from blood, are you talking about antigen or antibodies? Kindly narrate your question more specific.

  • Argyrides Argyrou added an answer:
    Has anyone measured or come across the value for the intracellular volume of M. tuberculosis?

    I would like to know the average volume of the cytosol of M. tuberculosis, or a sound approximation of this value.

    Argyrides Argyrou · GlaxoSmithKline plc.

    If you approximate a TB cell as a cylinder, 4 um height (h) and 0.5 um radius (r), then the volume = pi X r(squared) X h = 3 e-18 m(cubed) = 3 e-15 litres = 3 e-3 pL = 3 atto L

  • Lelamekala Vengidasan added an answer:
    Does anyone have experience cloning: 6.7 kb vector and 7.9 kb insert ?
    I am trying to clone a 7.9kb insert (from pGOAL19) in 6.7 kb (p2NIL) of vector and not getting it. I am using chemical competent cells. I want to ask the size constraint of plasmid for chemical competent cell? What is the maximum size of plasmid that can be transformed in chemical competent cells? do i have to use electroporation as size of my Vector plus insert will be around 15 kb?
    Lelamekala Vengidasan · University of Science Malaysia

    Do you you grow the cells in 30oC?

  • Silvia Dari added an answer:
    Can anyone recommend studies onto the diagnosis and management of tuberculosis related pleural effusions?

    I want to work out the best way of managing a slowly resolving tb effusions.

    Silvia Dari · Azienda Sanitaria Locale Viterbo

    Hello Adam,
    I hope to help you


  • Marc-Antoine Perrenoud added an answer:
    Does anyone know which kit is the best for large spectre PCR (identifiactions Eubacterias, mycobacterias, resistance genes TB)?

    I'm starting my tests next week, I will test 4 different kits from 4 brands and I desire to know if anyone has tested FastPCR for diagnosis purpose with one of those ready-to-use pcr mixes? I Could use some guidance about which one will be the best.

    1. Roche Fastart PCR Master
    2. Takara Clontech Premix Ex Taq Hot Start Version
    3. Applied Biosystems AmpliTaq Gold Fast mastermix
    4. Kapa Biosystems Fast HotStart Readymix(2x)

    The goal is simply to detect pathogens and identify them in culture or directly in samples patients. I also need to be able to analyse resistances genes. I'm trying to make my amplification method a lot faster than it's actually is (about 2:45 now)..

    Thanks a lot !

    Marc-Antoine Perrenoud · University Hospital of Lausanne

    I started my PCR tests 2 weeks ago and i already dropped 3 Master mix due to way too high sensibility, probably those mixs are better for use in human genomics.

    (Roche Fastart PCR Master, Takara Clontech Premix Ex Taq Hot Start Version, Kapa Biosystems Fast HotStart Readymix(2x)

    So I choose the Applied Biosystems AmpliTaq Gold Fast mastermix who seems to works fine for now with a high sensibility of 10^2cp/5ul for large spectre research of eubacterias, with no contaminations and a PCR time of about 45minutes my results were fine enought to continue with all my criterias (Mycobacterias, 28S panfungal, 18S panfungal, Resistance gene INHA, RPOB, KATG, and OXYR.) I'll see next week if it works for those criterias too.

  • Muhammad Javed added an answer:
    How do you rate the success of diagnosis of tuberculosis from blood through PCR?

    Thanks in advance for your replies.

    Muhammad Javed · Hamdard University

    In under developed countries the cost of PcR is very high. A positive tuberculin test in the absences of BCG helps better than pcR

  • Alexandre Carvalho added an answer:
    Should INH prophylaxis be done in patients with long term steroid use?

    45 year-old women was admitted to OPH d/t retinal vasultis. She has a plan to recieve long term and high dose steroid. But, her chest X-ray showd inactive tuberculosis and no history of treatment of TB. Should she take INH for prevention of occurence of acvtive TB ?

    Alexandre Carvalho · University of Minho

    If tuberculosis reactivation is a concern, we can not rely only on X-ray to decide. It is necessary to determine the existence of latent tuberculosis with tuberculin test and, if not definite, with IGRA.

    I believe long term corticotherapy is not an indication for INH prophylaxis, though.

About Tuberculosis

Any of the infectious diseases of man and other animals caused by species of MYCOBACTERIUM.

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