The typically ‘atypical’ radiographic presentation of tuberculosis in advanced HIV disease

Abstract

Tuberculosis (TB) is the most common pulmonary complication of the human immunodeficiency virus (HIV)-infection, worldwide. The World Health Organization estimates that there are 5.6 million persons in the world co-infected with Mycobacterium tuberculosis and HIV. 1 Over 90% of these dually-infected individuals reside in developing nations. In sub-Saharan Africa, an area endemic for both infections, TB produces a tremendous burden of disease. In comparison, TB is still a relatively infrequent cause of pulmonary disease among HIV seropositive patients in the USA and other industrialized countries. However, its importance as a pulmonary complication of HIV-infection has increased significantly over the last few years, primarily because of its association with nosocomial outbreaks of multidrug resistant TB 2 and its relatively high frequency in certain high risk populations (i.e., injection drug users)? Nosocomial outbreaks of MDR-TB have highlighted the importance of rapidly identifying and isolating potentially infectious TB patients. Unfortunately, our ability to recognize TB in the setting of HIV infection is limited because of the often 'atypical' clinical and radiographic presentation of TB and the many other possible causes of pneumonia. Early in the HIV epidemic, reports describing the clinical and radiographic presentation of TB concentrated on the findings in patients with advanced HIV infection. These patients were reported to have 'atypical' radiographic presentations, which were consistent with primary TB. 4,5 That is, they were characterized by lower zone infiltrates, thoracic adenopathy, and lack of cavitation. In one of the earliest reports, Pitchenik and Rubinson 4 described a 'typical' radiographic pattern in only one (6%) of 17 acquired immune deficiency syndrome (AIDS) patients. Studies from the US, 6 Zambia, 7 Rwanda, 8 and South Africa 9 have documented that HIV