OpiniãoSurgery has been employed in the treatment of TB since before the advent of chemotherapy. With the challenging prospect that more cases of MDR/XDR-TB are virtually untreatable with all available drugs or risk having serious sequelae, there has been re-evaluation of the role of pulmonary surgery as a way to reduce the amount of lung tissue with intractable pathology and to reduce the bacterial load. Large case series have reported that resection surgery may be safe and an effective adjunct when skilled thoracic surgeons and excellent postoperative care are available (127, 128).
The updated WHO consolidated guidelines include a conditional recommendation for elective partial lung resection (lobectomy or wedge resection) as an adjunct to the chemotherapy of MDR/RR-TB patients with resistance to additional medicines. The recommendation does not apply to radical pneumonectomy, which had no statistically significant effect (127). The recommendation was based on evidence from an IPD meta-analysis to evaluate the effectiveness of different forms of elective surgery as an adjunct to combination medical therapy for MDR-TB (127), and a systematic review and study-level meta-analysis (129).
The relative benefits of surgery are expected to depend substantially on the population subgroups that are targeted. The reviews for the guideline update in 2016 (11) could not provide a refined differentiation of the type of patient who would be best suited to an intervention, or the type of intervention that would carry the most benefit. The effect is expected to be moderate in the average patient considered appropriate for surgery. The odds of success for patients with MDR/RR-TB and resistance to fluoroquinolones and injectable agents were significantly lower when they underwent surgery compared with other patients (aOR: 0.4, 95% CI: 0.2–0.9) (127). This finding is likely to be biased, given that patients who underwent surgery would have had other factors predisposing them to poor outcomes – factors that could not be adjusted for. Programmes with limited access to surgery may target patients who remain sputum smear positive, who have resistance to many drugs and who have localized pulmonary disease. Computerized tomography, pulmonary function testing and quantitative lung perfusion or ventilation may have a role in the preoperative work-up.
Resection surgery should be timed to give the patient the best possible chance of cure with the least risk of harm. Thus, the timing of surgery may be earlier in the course of the disease when the patient’s risk of morbidity and mortality are lower (e.g. when the disease is still localized to one lung or one lung lobe). Generally, at least 2 months of therapy should be given before resection surgery, to decrease the bacterial infection in the surrounding lung tissue. Prognosis appears to be better when partial lung resection is performed after culture conversion. Even with successful resection, the total duration of treatment and the duration of treatment after culture conversion should be guided by the recommendations in Section 5, Section 6 and Section 7.
Partial lung resection for patients with MDR/RR-TB is only to be considered when good surgical facilities, staffed by trained and experienced surgeons, are available. Many programmes will have limited access to surgical interventions. In programmes with suboptimal surgical facilities and with no trained thoracic surgeons, resection surgery may increase morbidity or mortality. Specialized surgical facilities should include stringent infection control measures (given that infectious material and aerosols are generated in large quantities during surgery), mechanical ventilation and postoperative pulmonary hygiene manoeuvres. After resection, direct laboratory testing of the resection material (lung lesion) will be useful. If the results of laboratory testing differ between the resected material and other clinical specimens, the treating clinician may need to adjust treatment based on the results obtained from the resected material or other clinical specimens.
There are still many uncertainties about the role of surgery in MDR-TB treatment. All data available for the 2016 recommendations were from observational data from case series, which may be biased. For instance, it is likely that in choosing patients to be operated on there would have been systematic exclusion of patients deemed unfit for surgery and anaesthesia, such as older patients and those who were very sick with comorbidities (e.g. no patient with HIV in the dataset had undergone surgery) or extensive disease. There were not enough data on adverse events, surgical complications or longterm sequelae – some of which may be fatal – to allow for a meaningful analysis. Conversely, the effectiveness of surgery may have been underplayed in the analysis because of the lack of a suitable control group.