"Most cases occur in developing countries, although the incidence of tuberculosis has increased considerably worldwide".


What is tuberculosis?

Tuberculosis is a disease caused by human infection with the Koch bacillus (Mycobacterium tuberculosis).

Every year there are 8 million new cases worldwide and almost 3 million patients die from this infection each year. Most cases occur in developing countries, although with the AIDS epidemic, the incidence of tuberculosis has increased considerably worldwide. Spain is one of the western countries with the highest incidence of tuberculosis.

Not every person infected with the Koch bacillus develops tuberculosis disease. The vast majority of people suffer from asymptomatic or associated with mild symptoms identical to those of a viral respiratory infection, which subsides spontaneously and may leave some scar in the lung or lymph nodes. This picture is called primoinfection or primary tuberculosis.

Only 10% of people with primoinfection will eventually develop the tuberculosis disease; 5% will develop it in the first months after the primoinfection; and 5% will develop it late, even after several decades.

What are the symptoms of tuberculosis?

Primoinfection. In most cases, it evolves without symptoms and resolves without the patient noticing. It is more frequent in childhood. In case of presenting clinical, usually it does it as a febrile syndrome with affectation of the general state. Also it can produce more severe picture with high fever, loss of weight and extrapulmonary affectation. Most of the cases go unnoticed, being diagnosed a posteriori when the tuberculin test becomes positive or by the observation of pulmonary scars in a chest radiography.

Post-primary Tuberculosis. This is the disease caused by the reactivation of bacilli that have become dormant in lymph nodes or other organs (e.g., lungs) since the first infection. It can occur in any organ, although the most frequent location is the lung (80%).

Pulmonary tuberculosis. It can present with an insidious onset with productive cough, asthenia and sweating of months of evolution or with an acute onset with cough, hemoptysis (blood in the sputum) and high fever. The most characteristic symptom is coughing, which is usually accompanied by expectoration. It is not uncommon to be associated with pleural involvement, especially in young patients with acute onset of pleural pain and febrile syndrome.

The most common symptoms are:

  • Fever.
  • Extrapulmonary affection.
  • Productive cough.
  • Asthenia.

Extrapulmonary tuberculosis:

  • Miliary tuberculosis (by hematogenous dissemination): it is produced when the Koch bacillus spreads to other organs through the blood. It is usually a picture of weeks of evolution of fever, night sweats and constitutional syndrome, with the appearance of adenopathies and skin lesions. It is not very frequent and usually occurs in people with depressed immunity.
  • Bone tuberculosis: affectation of vertebral bodies producing mainly pain at the level of the affected intervertebral disc.
  • Genitourinary tuberculosis: usually asymptomatic. It can present mictional syndrome (dysuria or discomfort when urinating, urgency, lumbar pain) and general picture with fever, asthenia, and anorexia.
  • Tuberculosis meningea: general picture of fever and asthenia with later appearance of headache, rigidity of nape, endocranial hypertension and neurological focal signs.

Do you have any of these symptoms?

You may have tuberculosis

What is the cause of tuberculosis?

Transmission of Koch's bacillus occurs directly from person to person, usually from the patient with lung disease who exhales bacilli through the air with coughing, expectoration and speaking.

Usually, close and prolonged contact between the patient and the contact is necessary for transmission to occur.

Other forms of transmission, such as digestive, have lost importance due to the application of hygienic measures such as the pasteurization of milk.

What is your prognosis?

With the treatments available today, the prognosis for tuberculosis is excellent.

In general, two weeks after starting treatment, the infected patient stops being contagious and a progressive recovery of the general state begins. Within a few weeks, most patients can lead a normal life and return to work.
In people who have been exposed to the infection through intimate contact, Myocbacterium tuberculosis infection can be prevented by treatment with an antibiotic (it is the only case in which it is correct to use only one antibiotic) for 6 months.

But not everyone who has been in contact with a TB patient has to take the antibiotic.

At the present time, systematic vaccination is not indicated in Spain.

How is tuberculosis diagnosed?

<p>Imagen laboratorio de microbiolog&iacute;a&nbsp;</p>

Tuberculin (PPD) or Mantoux test: it consists of injecting into the subcutaneous tissue an extract containing antigens of the Koch bacillus, but not the whole bacillus, so it cannot produce infection.

If a person has antibodies against the bacillus, he will have a skin reaction after 2-3 days at the place of inoculation, characterized by induration, erythema and heat. If this reaction occurs, it means that the subject has been in contact with the bacillus at some point in his or her life.

It does not mean that there is an infection at the time of the test, but if the clinical circumstances are right, it can help establish the diagnosis.

The diagnosis of certainty is made with the isolation and identification of the bacillus in culture media.

Mycobacterium tuberculosis is a slow-growing bacillus and can take up to 8 weeks to develop on these culture media. For immediate identification of Mycobacterium tuberculosis, specific staining media (Ziehl-Neelsen or auramine) are used for samples in which infection is suspected.

Staining techniques are not very sensitive, so when no bacilli are observed in a sample but clinical suspicion is high, it is indicated to start treatment until culture results are available (up to 8 weeks).

The Clinic has a Biosafety Laboratory level 3 (BL3), which allows the handling of biological agents such as tuberculosis. In this laboratory it is possible to isolate, culture and study the sensitivity to anti-infective agents, which will allow establishing the most appropriate treatment.

How is tuberculosis treated?

The Koch bacillus has a great capacity to protect itself against antibiotics by developing resistance when these are used individually. Therefore, the use of combinations of antibiotics is always necessary.

Treatment can be carried out on an outpatient basis, although respiratory isolation is required, at least for the first two weeks.

First choice antituberculosis drugs include isoniazid, rifampicin, pyrazinamide, ethambutol, and streptomycin.

International infectious disease associations currently recommend starting treatment with three first-line antibiotics for 2 months, followed by two for an additional 4 months.

The most common treatment regimen is a combination of isoniazid, rifampicin, and pyrazinamide for the first two months, followed by four months of isoniazid and rifampicin. Depending on the case, longer and more extensive treatment regimens may be needed.

Where do we treat it?


The Infectious Diseases Service
of the Clínica Universidad de Navarra

This area works on the diagnosis and treatment of diseases produced by an infectious agent, which can be bacteria, virus, fungus and protozoa. Infections affect people by causing very different processes that can be located in any tissue of the human body, so it requires a specific approach.

This area carries out its activity on three fronts: care work, focused on the diagnosis and treatment of infectious diseases; teaching, with training of medical students, resident doctors and nurses; and research vocation, through the development of clinical and laboratory studies.

Organized in care units

  • Infections associated with biomaterials.
  • Nosocomial infections (multi-resistance).
  • Infections in immunosuppressed patients.
  • Community infection.
  • Traveler's medicine.
  • Prudent use and optimization program of anti-infective therapy.
  • Control of infection by multi-resistant microorganisms.
Imagen de la fachada de consultas de la sede en Pamplona de la Clínica Universidad de Navarra

Why at the Clinica?

  • We perform the traveler's assessment and analytical tests in less than 24 hours.
  • Second opinion consultation when the infection has not yet been resolved.
  • We ensure the prudent use of antibiotics.

Our team of professionals

Specialists in the Infectious Diseases Area with experience in the treatment of tuberculosis