Title : Mycobacterium: Mycobacterium Tuberculosis



Mycobacterium: Mycobacterium Tuberculosis

Mycobacterium tuberculosis came from the Mycobacterium genus, an acid fast bacilli. It is resistant to air and drying. The TB bacilli are able to survive for months in dried sputum. It is transmitted through inhalation of droplet infection like in sneezing and coughing. It can be also transmitted through ingestion of contaminated substance or direct contact of formites having the secretions of this infection.

Mycobacterium tuberculosis is responsible for the disease called tuberculosis.  Tuberculosis is a highly contagious disease involving the lungs as manifested by the formation of tubercles in the tissue which undergo caseation, necrosis or fibrosis and calcifications.  M. tuberculosis does not only infect the lungs but other parts of the body including the skin which later on causes lupus vulgaris; neck glands which leads to scrofula; the spine which results to pott’s disease and the nerves in which can lead to neurological damage causing spondylitis.


Common tuberculosis is on the lungs, known as pulmonary tuberculosis and it is usually characterized by:

§  Chest pain

§  Hemoptysis

§  Prolonged productive cough

§  Fever at night

§  Night chills and sweats

§  Loss of appetite

§  Weight loss

§  Insomnia

Tuberculosis in children is termed as primary complex and often has these signs and symptoms:

§  Cough for more than 2 weeks

§  Fever with no cause for more than 2 weeks

§  Weight loss

§  Anorexia

§  Unable to respond to antibiotic therapy

Pulmonary tuberculosis is characterized into:

Category 0 – there is no history of PTB exposure.

Category 1– there is positive PTB exposure, negative PPD interpretation and there are no signs and symptoms of the disease.

Category 2 – there is positive PTB exposure, positive PPD interpretation and there are no signs and symptoms of the disease; if interpreted this people have been exposed to the PTB infection.

Category 3 – there is positive PTB exposure, positive PPD interpretation with presence of signs and symptoms of the disease; if interpreted this people have an active PTB infection.

Category 4 – there is positive PTB exposure, positive PPD and is recovering from PTB infection; the client is on multi drug therapy.

Category 5 – there is positive PTB exposure, negative PPD interpretation but with presence of PTB signs and symptoms; the client is suspected to have PTB infection.

In the diagnosis of an active infection, PPD or Mantoux test is usually done. A pure protein derivative (PPD) is injected intradermally in the skin which results to a bleb. The skin test is read after 48- 72 hours. It is expected to be positive if the bleb has reddened, become edematous and with induration.  10mm or more is the expected induration once the patient is positive for PTB.

Pulmonary tuberculosis is treated with multi drug therapy.  First line anti TB drugs is rifampin+ isoniazid + streptomycin+ ethambutol which usually lasts for 6 months. Second line drugs include the pyrazinamide, cycloserine viomycin and p-aminosalicylic acid which lasts for 1-2 years of therapy.

Nursing Consideration

Nurses should emphasize to patients and folks the importance of drug compliance so as to prevent the incidence of multi-drug resistance. The drugs used for PTB chemotherapy often have dangerous side effects like for example Rifampin drugs are hepatotoxic; Isoniazid inhibits the absorption of Vitamin B6; Pyrazinamide leads to hyperuricemia; Ethambutol causes optic neuritis that is why ophthalmologic checkups are very important; and Streptomycin causes ototoxicity.  To prevent the spread of infection to young children, it a must that the child has received and completed his booster of BCG. The patient with an active infection should be isolated from other members of the family. Inside the hospital room, it is better to let the patient wear the mask instead of his caregivers because he is the one harboring the infection.


Sources: http://nursingcrib.com/microbiology/mycobacterium-mycobacterium-tuberculosis