Removal of a Lung Due to Tuberculosis

Tuberculosis (TB) is one of the world's worst killer diseases. Each year there are about two million TB-related deaths worldwide. One-third of the world's population is infected, although the bulk of these infections are latent and thus cannot be transmitted. In recent years cases of antibiotic-resistant TB have become increasingly common. Faced with this difficult challenge, doctors must sometimes resort to surgery to help treat TB patients. One such surgical procedure is called pneumonectomy, or removal of a lung.

XDR-TB

• Most TB infections are latent, meaning the carrier exhibits no symptoms and the infection cannot be transmitted. Some 5 to 10 percent of people with latent TB will go on to develop the active form of the disease. Typically doctors treat TB with antibiotics like isoniazid and rifampin. Unfortunately, an increasing number of TB infections called MDR-TB are resistant to these drugs. Doctors have second-line drugs available, but some TB bacteria have developed resistance to these also. These super-resistant TB cases are called extensively-drug resistant TB or XDR-TB and pose a mounting threat to public health in many countries around the world. Although data on the extent of XDR-TB is still limited, it's known that as of 2008 some 45 countries had confirmed cases of XDR-TB, the United States being among them.

Pneumonectomy

• Surgical removal of a lung is called pneumonectomy. It's a major procedure that carries the risk of a number of life-threatening complications including blood clots in the remaining lung, infection and organ failure. Pneumonectomy is typically performed on lung cancer patients, but the first pneumonectomy in 1895 was actually carried out to treat a patient with tuberculosis and emphysema. In cases where the patient is infected with XDR-TB, doctors occasionally are forced to remove a lung to treat the patient's condition.

Considerations

• Generally doctors use four different drugs in combination to treat XDR-TB. The treatment period lasts a year and a half or longer. Treatment doesn't guarantee survival for patients with XDR-TB, however, and sometimes areas of persistent infection remain even after protracted chemotherapy, or the disease may cause permanent lung damage. Doctors must sometimes rely on surgery in these cases despite the risks associated with pneumonectomy or other surgical procedures.

Mortality Rates

• A number of published studies have documented results from cases where pneumonectomy or other surgical procedures were performed on TB patients. An article in the Chinese Medical Journal in 2010, for instance, recorded a hospital mortality rate of 12.8 percent out of 47 pneumonectomies performed to treat TB and other inflammatory lung conditions. Another article from the Journal of Thoracic and Cardiovascular Surgery in 2007 recorded results for 23 patients who underwent surgery (either pneumonectomy or resectioning part of the lung) to treat TB or complications of TB. The hospital mortality rate was 4.3 percent. Again there were multiple cases of major complications. XDR-TB is in any case associated with a much higher mortality rate than MDR-TB.

Significance

• While surgery was sometimes used to treat tuberculosis in the early 20th century, the advent of antibiotics in the 1940s relegated surgery to the sidelines where TB treatment was concerned. The modern use of surgery in some tuberculosis cases is thus a reversion to the pre-antibiotic era and demonstrates the alarming extent to which TB has been able to evolve antibiotic resistance. Curbing this fast-growing threat will be a major challenge for public health authorities and pharmaceutical firms in the years ahead.