Atypical radiological images of pulmonary tuberculosis in 192 diabetic patients: a comparative study

SETTING: Comparative studies of pulmonary tuberculosis images in diabetics have yielded conflicting results. OBJECTIVE: To assess radiological images of pulmonary tuberculosis in a lar ge population of diabetic patients. DESIGN: Radiographs from in-patients admitted with pulmonary tuberculosis a nd diabetes (TBDM group, n = 192) were reviewed and compared with a control group of patients with pulmonary tuberculosis alone (TB group, n = 130). RESULTS: Both groups had a similar evolution time of tuberculosis (similar to2 years). Statistical differences were observed as follows: TBDM patients were older (51.3 +/- 0.9 vs. TU group 44.9 +/- 1.8 years, mean +/- SEM), a nd had a decreased frequency of upper (17% vs. 56%), and an increased frequ ency of lower (19% vs. 7%) and upper + lower (64% vs. 36%) lung field lesio ns. More TBDM patients developed cavitations (82% vs, 59%) more often in th e lower lung fields (29% vs. 3%). More multiple cavities were seen in TBDM patients (25% vs. 2%), TBDM group had a lower total leukocyte count (8836.7 +/- 219.5 vs. 10013.1 +/- 345.2 cells/mm(3)), mainly due to a lower number of non-lymphocyte cells (6815.8 +/- 221.8 vs. 8095.7 +/- 321.9 cells/mm(3) ). Multiple logistic regres sion showed that being a diabetic patient was t he most important factor determining lower lung field lesions and cavities. CONCLUSIONS: This study in a large number of diabetics with pulmonary tuber culosis confirmed that their chest X-ray images significantly depart from t he typical presentation. Clinicians must keep this in mind to avoid misdiag nosis.