Monitoring treatment responses in patients with pulmonary TB using serial lung gallium-67 scintigraphy.
OBJECTIVE
Gallium-67 scintigraphy is more sensitive than chest radiography in a single concurrent detection of pulmonary tuberculosis (TB). As for inflammation, the intensity of pulmonary uptake of 67Ga citrate theoretically is a function of the inflammation level in the lung. To maximize clinical applicability of 67Ga scintigraphy in the evaluation of pulmonary TB, we prospectively assessed serial qualitative associations between intensity of the uptake of 67Ga citrate and the severity of lung inflammation, reflected by the burden of Mycobacterium tuberculosis in the sputum of patients undergoing anti-TB chemotherapy.


METHODS
Each enrolled patient had chest radiographic, microbiologic, 67Ga imaging, and semiquantitation of sputum acid-fast bacillus (AFB) assessments before and at the third and sixth months after receiving anti-TB chemotherapy. The burden of pulmonary M. tuberculosis (presumably, in proportion to the semiquantitation of AFB in sputum) and the intensity of 67Ga citrate uptake in the lung at each synchronized assessment were regarded as a paired variable. Odds ratios were obtained from odds (derived using generalized estimating equations) in favor of higher pulmonary 67Ga uptake in differing scores of semiquantitation of sputum AFB. Linear trend for pulmonary 67Ga citrate uptake corresponding to varied pulmonary M. tuberculosis burdens was assessed using contrast analysis of their odds ratios.


RESULTS
Thirty patients (24 men and six women) with pulmonary TB were enrolled. Eighty-six paired semiquantitations of sputum AFB-67Ga-scintigraphic studies were collected. Twenty-six patients were cured of their pulmonary TB. The pulmonary 67Ga uptake increased in proportion to the higher score of semiquantitation of sputum AFB (p = 0.009, for trend).


CONCLUSIONS
In patients with pulmonary TB, the higher the burden of M. tuberculosis in the lung, the higher the intensity of pulmonary 67Ga citrate uptake. Serial 67Ga-scintigraphy examinations are helpful in evaluations of the effectiveness of anti-TB therapy when assessments based on chest radiography are difficult.
Liu
Shih-Feng
SF
Division of Pulmonary & Critical Care Medicine, Department of Internal Medicine, Chang Gung Memorial Hospital-Kaohsiung Medical Center, Chang Gung University College of Medicine, Taiwan, ROC.
Liu
Jien-Wei
JW
Lin
Meng-Chih
MC
Lee
Chiang-Hsuan
CH
Huang
Hsu-Hua
HH
Lai
Yung-Fa
YF
D000328:Adult; D000368:Aged; D000995:Antitubercular Agents / Q000627:therapeutic use; D005260:Female; D005710:Gallium Radioisotopes; D006801:Humans; D008297:Male; D008875:Middle Aged; D009169:Mycobacterium tuberculosis / Q000302:isolation & purification*; D011446:Prospective Studies; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D013183:Sputum / Q000382:microbiology; D014397:Tuberculosis, Pulmonary / Q000000981:diagnostic imaging* / Q000188:drug therapy
D000995:Antitubercular Agents; D005710:Gallium Radioisotopes; D019275:Radiopharmaceuticals