[Lower lung field tuberculosis]

Tuberculosis (TB) that affects lower lung fields (LLFTB) is infrequent in the adult population and is generally associated with immunodeficiency. The objective of our study was to determine the incidence of LLFTB in our patients population and compare the characteristics of these pa-tients with those who presented TB of typical pulmonary localization. We studied 42 patients with LLFTB retrospec-tively between 2004 and 2008 and compared them to 84 patients with TB of typical localization (control group). HIV-positive patients were excluded. LLFTB represented 6% of the pulmonary TB cases. No significant differences were found with respect to age, sex, the presence of cavities in chest x-rays, days of evolution, and albumin levels. LLFTB had a significantly greater proportion of comorbilities (p < 0.001), the presence of condensation (p < 0.001), and unilateral involvement (p < 0.001), with a higher number of hospital admissions (p = 0.02). The observation that only 16 of the 42 patients with LLFTB (38%) had a notable comorbility is important. Thus, LLFTB can be present without associated comorbilities and must be suspected in pneumonias that have a torpid evolution regardless of pulmonary localization.