Abstract: Objective To investigate the causes for delayed absorption pneumonia patients misdiagnosed as pulmonary tuberculosis and to improve the clinical differential diagnosis ability on these two pulmonary diseases.  Methods Retrospective analysis of 16 cases with delayed absorption pneumonia who were misdiagnosed as pulmonary tuberculosis.  Results The clinical symptoms ofthese patients included10 caseswithfever, amongwhom 3 caseshad high grade fever, 4 cases had medial grade fever and 3 cases had low grade fever;2 cases with night sweat. All patientshadnegative acid fast bacteria; Of 16 cases 12cases showed that WBC were 4.0~10.0×10⁹／L, 7 cases were positive on TST result used PPD 5IU, 16 cases’ lesionlocated in the apical and rear segments of the upper lobes or the superior segments of the lower lobes, 2 cases had the history of pulmonary tuberculosis.  Conclusion The main causes of misdiagnosis are as follows:the clinical symptoms of delayed absorption pneumonia are atypical, Chest X-ray appearance and routine blood test Results are similar to that of pulmonary tuberculosis and the diagnostic value of PPD test is over-estimated.Comprehensive analysis of the clinical data and observing the focus dynamically after anti-inflammatory treatment should be important measures to avoid delayed absorption pneumonia misdiagnosed as pulmonary tuberculosis in clinical practice.

Key words: pneumonia, tuberculosis,pulmonary, diagnostic errors