Home » Frequently asked Questions on Health » What is atypical tuberculosis (TB)?

What is atypical tuberculosis (TB)?

Q: What is atypical tuberculosis (TB) non-tuberculous mycobacteria (NTM) or Mycobacterium Other Than Tuberculosis (MOTT) infection? How is it treated?

A:The term "Atypical TB" may be used to signify a group of closely related diseases caused by bacterial organisms belonging to non-tuberculous mycobacteria (NTM) or Mycobacterium Other Than Tuberculosis (MOTT). Although they share some common characteristics to the bacteria casing TB namely Mycobacterium tuberculosis, there are significant differences in the spectrum of diseases (e.g. incidence of extra-pulmonary disease such as skin, lymph node, disseminated disease, intestinal involvement, catheter related infections), patient characteristics (e.g. immunocompromised conditions due to HIV or chemotherapy), presentation, clinical course and outcome of disease (e.g. chest infection due to MOTT), specific drug, (e.g. need of macrolides such as Clarithromycin in regimens) and duration of treatment (e.g. longer duration of treatment~ 2 years, in chest infection). MOTT or NTM is not a single organism or a group, but consists of a diverse group of related organisms all belonging to the genus Mycobacteria. Although all of them are acid-fast bacilli, and may closely resemble M. tuberculosis when examined microscopically, they differ from each other in their growth requirements and growth characteristics on culture (e.g. need of light to produce pigments photochromogens, as opposed to scotochromogens, and non-chromogens), time required to grow in culture media (e.g. rapid growers generally grow within a week) and biochemical and genetic characteristics.

The diseases caused by NTM or MOTT have a much more indolent course of disease compared to that of M. tuberculosis. Since many of these organisms are present in the environment isolation of these organisms from clinical specimens may represent colonisation and contamination and may not necessarily correlate with disease. The treatment of these groups of pathogens depends on the specific bacteria involved (as identified by culture), disease or organ affected (chest, lymph node, skin, disseminated infection), and drug susceptibility of the specific pathogen. Some common examples of diseases caused by MOTT or NTM are M. avium-intracellulare complex casing chest infection in immunocompromised patients (e.g. those with HIV infection and low CD4 counts), M. scrofulaceum causing scrofula a form of lymphadenopathy (disease of the lymph nodes), M. marinum (causing swimming pool or fish tank granuloma- a type of skin infection). Although some drugs used in the treatment of tuberculosis are also used in the treatment of MOTT infections (such as rifampicin and ethambutol), the choice of a third agent (e.g. clarithromycin), prophylactic agents (e,g. azithromycin or clarithromycin or ciprofloxacin) are different from those of TB. In some cases surgery (e.g. excision of an affected lymph node) may be required. The treatment recommendations will also depend on whether the patient is HIV positive or negative.


................... Advertisement ...................




Using 0 of 1024 Possible characters
Choose Topic

Latest stories

Florida: Diabetics Selling Insulin And Testing Supplies In Black Market

Tue, 26 Sep 2017 17:30:43 IST
In Florida, diabetes patients are indulging in black marketing and illegal selling of their insulin and testing supplies and are trying to making a fortune out of their medical condition.

Tamil Nadu: Women Lack Access To Contraceptive Options

Tue, 26 Sep 2017 16:30:44 IST
One of the most urbanized states of the country, Tamil Nadu has witnessed an eight percent decrease in the use of all forms of contraceptives in the last decade. This decline in contraceptive use is bad news for women.

Yoga Can Hurt If Not Done Properly, Say Experts

Tue, 26 Sep 2017 15:30:15 IST
Where yoga is known to be a great healer and a contributor in improving physical strength and body flexibility, it can also have adverse effects if not done properly. Deepak Jha, yoga expert, has pointed out certain health problems you may face if you practice yoga poses incorrectly.

Marijuana Helps In Avoiding Hard Drugs, Study; Health Benefits Of Marijuana

Tue, 26 Sep 2017 13:30:36 IST
Marijuana may in fact prevent people from progressing to harder drugs like cocaine or ecstasy, as per scientists. Know the rare health benefits of marijuana.

Maharashtra: Anganwadi Workers Continue To Strike, Parents and Children Suffer

Tue, 26 Sep 2017 12:30:24 IST
Anganwadi workers have been on strike across the entire state of Maharashtra since September 11th, and this, of late, has started bothering the parents of children who rely on these anganwadis for their daily meals. The children have now resumed eating home-cooked meals and are even resorting to cheap, junk food.