To assess whether diagnostic error could have been avoided for patients who were mistakenly hospitalized for tuberculosis (TB) when in fact TB was not present or who were mistakenly hospitalized for another disease when they in fact had TB.

This cross-sectional, descriptive study examined the medical records of all patients admitted to the TB ward of Hospital San Juan de Dios (SJD) in Santa Cruz, Bolivia over a period of 28 consecutive months.

Sixty-four (9.8%) of the 650 patients admitted were diagnosed incorrectly. Upon admission, all relevant information was recorded in the medical histories of 10 patients (15.6%) and at the physical examination of 28 patients (43.8%). Taking of a full medical history, performing a complete physical examination, and correctly interpreting the chest film would have led to correct diagnosis for 34 patients (53.2%) and would have been suggestive for 23 (35.9%) more. Such information plus the results of a sputum smear examination could have established or ruled out the presence of TB for 32 patients (50.0%) and suggested the appropriate diagnosis in another 27 patients (42%).

The careful use of basic diagnostic tools could prevent serious clinical errors related to TB before such patients are admitted to a specialized ward.