Tuberculosis is an infectious disease caused by a bacterium known as Koch's bacillus (BK). Only 10% of individuals exposed to Koch's bacillus will develop tuberculosis symptoms. In the remaining 90%, the bacterium is controlled by the immune system, becoming inactivated, unable to be transmitted or causing any sign of disease. These patients, however, may develop tuberculosis sooner if there is any drop in their immune defenses, allowing the bacterium to proliferate.
In patients who develop active tuberculosis, the vast majority do so through pulmonary tuberculosis. However, Koch's bacillus can affect other organs of the body than the lungs, such as lymph node tuberculosis, bone tuberculosis, tuberculosis of the skin, intestinal tuberculosis, cerebral tuberculosis, etc.
In this article we will address the most common signs and symptoms of pulmonary tuberculosis and extrapulmonary tuberculosis. As the pulmonary form is the most usual, we will emphasize its symptoms.
1. Fever
Fever is one of the most common symptoms of tuberculosis, whether in the pulmonary form or in tuberculosis of other organs. In general, the fever is high, above 38ºC, daily and with predominance at the end of the day, called an evening fever. In the elderly, however, tuberculosis can occur without fever.
2. Night sweats
Another common tuberculosis symptom. In addition to evening fever, it is also usual for patients to experience night sweats. In some patients with tuberculosis, night sweats can occur even without the presence of fever.
3. Cough
Cough is the most common symptom of pulmonary tuberculosis, but it is not usually found in other forms of tuberculosis. A patient with urinary or gastrointestinal tuberculosis, for example, will only have a cough if he/she also has active pulmonary tuberculosis.
The pulmonary tuberculosis cough is chronic, lasting weeks. It usually begins as a dry cough, worsening over the course of days, and may develop into a purulent cough with yellow-green expectoration.
The tuberculosis phlegm cough is different from the pneumonia cough because it is a more drawn picture, which evolves for weeks. In pneumonia the picture of high fever and cough develops in a few hours, causing the patient to seek medical help in 24-48 hours. In tuberculosis, the patient only feels bad enough to seek a doctor for several days, sometimes weeks, after the onset of illness.
4. Expectoration with blood
As the days pass, the purulent expectoration can turn into bloody expectoration, which is called hemoptysis. Blood- borne phlegm is a typical symptom of tuberculosis in more advanced stages.
5. Shortness of breath and tiredness
Shortness of breath is a common symptom of pulmonary tuberculosis and usually occurs in later stages when lung involvement is already widespread. Shortness of breath at the onset of the condition occurs only during exertion, but as the infection progresses, it begins to appear even at rest.
Shortness of breath may also be caused by involvement of the lung pleura, causing pleural effusion (water in the pleura) or pneumothorax (air in the pleura).
Fatigue, however, is different from lack of air and occurs in any form of tuberculosis, is characterized by lack of strength, feeling sick, desire to lie down all the time and discouragement. Tiredness is not due to lung involvement, but due to severe infection.
6. Chest pain
Pain in the thoracic region is another common symptom of pulmonary tuberculosis. It can occur for a variety of reasons, from tuberculosis itself, to the effort caused by chronic cough, or even from the infection of the pleura, which is characterized by pain arising during deep breathing, called pleuritic pain.
Chest pain in cases of pulmonary infection due to tuberculosis is usually in the region of the back, usually on the side of the most affected lung.
7. Weight loss
Weight loss and lack of appetite occur in all forms of tuberculosis. It is common for the patient to report to the doctor scared with a loss of 5 to 10 pounds in the last weeks.
8. Increased lymph nodes
The appearance of one or more lymph nodes that are enlarged and palpable by the body is a typical symptom of lymph node tuberculosis.
The most common presentation is the appearance of a single enlarged, non-painful lymph node in a young adult with no other symptoms, such as fever, weight loss, coughing or tiredness. However, it is not unusual for the patient to have more than one enlarged ganglion or to have the lung and lymph node forms together, causing the symptoms described above to be present.
Examination of the lymph node reveals a tight, tightly adhered mass. In about 70% of the cases, the ganglion appears in the region of the neck. Other sites where lymph nodes appear in ganglionar tuberculosis are the armpit, above the clavicle, elbow, or groin region. Radiological examinations can identify enlarged lymph nodes in deeper regions, such as in the abdominal cavity and in the mediastinum (region within the thorax).
9. Bone pain
Bone tuberculosis usually manifests as a pain in the bones, especially lower back pain, due to involvement of the spinal vertebrae by the infection (called Pott's disease).
Bone tuberculosis is not a very common form and pain is usually mild to moderate at the onset of the disease. If there is no fever and weight loss, the physician usually does not (and should not) initially suspect tuberculosis in patients with complaints of back pain. The radiography of the spine is usually normal in the initial phases, and it is necessary to perform a CT scan or magnetic resonance imaging for the early diagnosis.
10. Blood in the urine
Tuberculosis of the urinary system usually presents as a picture of urinary tract infection that does not cure with traditional antibiotics and is not identified by urocultures.
The bacterium usually lodges in one of the kidneys and causes pain in the lumbar region associated with blood and pus in the urine, sometimes microscopically, only detectable by laboratory tests of urine. If left untreated in time, it leads to destruction of the kidneys.
More than 90% of the patients infected with Koch's bacilli will develop the pulmonary form of the disease, with cough, fever and weight loss being the most common symptoms of the disease. Because extrapulmonary forms are less common, the diagnosis may be more difficult to establish, especially if the patient does not also have the typical systemic symptoms of tuberculosis, such as weight loss, fever and/or fatigue.
There are dozens of forms of extrapulmonary tuberculosis, which leads to dozens of forms of clinical presentation of the disease. We have listed above only the most common forms, but patients with tuberculosis of the central nervous system, intestines, genitals, skin, etc., may have completely different symptoms than those described above. In common, only fever, emaciation and fatigue, which will not necessarily be present in all cases.
