Acute miliary tuberculosis presenting as acute respiratory failure

Pulmonary tuberculosis presenting as acute respiratory failure: radiologic findings

PURPOSE

The purpose of this work was to describe the radiologic findings of pulmonary tuberculosis in patients who presented with acute respiratory failure.

METHODS

We included patients who had newly diagnosed active pulmonary tuberculosis and who presented with acute respiratory failure. Initial chest radiographic (n = 17) and high-resolution CT (n = 11) findings of each patient were analyzed retrospectively.

RESULTS

Of 1,010 patients with active pulmonary tuberculosis, 17 patients (1.7%) presented with acute respiratory failure. Nine (53%) of the 17 patients died. The most common initial chest radiographic findings were small nodular lesions (16/17; 94%), consolidation (13/17; 76%), and ground-glass opacity (12/17; 70%). Eleven (69%) of 16 nodular lesions, 9 of 13 (69%) consolidations, and 10 of 12 (83%) ground-glass opacities were bilateral. On HRCT (n = 11), miliary micronodular lesions were seen in 6 patients (55%), whereas bronchogenic spread of tuberculosis with disseminated centrilobular nodules and tree-in-bud appearance was seen in 5 patients (45%). Diffuse areas of ground-glass attenuation were seen in all six patients with miliary nodules and four of five patients with bronchogenic spread of tuberculosis.

CONCLUSION

Patients with pulmonary tuberculosis occasionally present with acute respiratory failure. In this condition, chest radiograph most commonly shows bilateral small nodular lesions mixed with consolidation or ground-glass opacity, whereas HRCT demonstrates findings of miliary or bronchogenic disseminated tuberculosis with diffuse areas of ground-glass attenuation.

Miliary tuberculosis and adult respiratory distress syndrome

Although, miliary tuberculosis is an unusual cause of severe acute respiratory failure, we describe nine patients with miliary tuberculosis who developed adult respiratory distress syndrome. This complication occurred in seven patients despite treatment with antituberculous drugs. In two patients who developed the syndrome, miliary tuberculosis was diagnosed only at postmortem. The presence of pulmonary hypertension in all cases and disseminated intravascular coagulation in seven cases suggests a possible pathophysiologic relationship with severe pulmonary vascular damage. The high mortality rate (88.8%) was associated with nonpulmonary organ system failure. Miliary tuberculosis should be considered in patients with adult respiratory distress syndrome of unknown etiology, and simple diagnostic procedures such as sputum, bronchial brushing, and gastric examination should be followed by invasive diagnostic procedures to confirm this etiology. Since untreated miliary tuberculosis is usually fatal, early recognition of this disease is of great importance, and specific therapy may play a lifesaving role.

The adult respiratory distress syndrome bronchogenic pulmonary tuberculosis

In three cases of pulmonary tuberculosis associated with the adult respiratory distress syndrome the clinical features, which were similar to those of patients with miliary tuberculosis and adult respiratory distress syndrome, included a history of cough, fever, and dyspnoea on effort, and the physical signs of fever, tachypnoea, pulmonary adventitious sounds, tachycardia, and hepatomegaly. In these cases the radiological features, though suggestive of diffuse pulmonary oedema, were more prominent on the side in which the cavitatory lesion appeared. The diagnosis of tuberculosis was made easily from direct examination of sputum. Despite early ventilatory support and antituberculous therapy, two of the three patients died. Postmortem examination of the lungs in these cases showed evidence of acute alveolar damage (loss of type 1 pneumocytes and the presence of hyaline membranes within alveolar ducts) and of chronic alveolar damage (interstitial and alveolar fibrosis).

Active tuberculosis undiagnosed until autopsy

In this report 21 patients in whom tuberculosis was the primary cause of death, but which was not diagnosed until necropsy, are reviewed. Of the 21 deaths, 11 were due to pulmonary tuberculosis and 10 to miliary tuberculosis. Proper evaluation of the following factors might have led to the correct diagnosis in many of the patients: A family history of tuberculosis, prior pleurisy, a gastrectomy, diabetes mellitus or end-stage renal failure; all can be associated with an increased incidence of tuberculosis. A negative tuberculin skin reaction does not exclude the presence of active tuberculosis. In the search for Mycobacterium tuberculosis, the examination of just one or two sputum specimens is not an adequate bacteriologic investigation. A positive gastric smear can have diagnostic importance. Ascitic fluid findings can be characteristic of tuberculous peritonitis. A negative bone marrow aspirate for acid-fast bacilli does not exclude miliary tuberculosis. Significant anemia, high fever and leukopenia increases the possibility of tuberculosis. The persistence and/or progression of lung infiltration, irrespective of supposedly specific antibiotic therapy, strongly suggests tuberculosis. Miliary tuberculosis can present as an adult respiratory distress syndrome. All but one patient in this series had fever. the failure to diminish the pyrexia believed due to specific lung infections with presumably effective antibiotics, and the inability of therapy to control other conditions thought to cause the fever indicate the presence of tuberculosis. Tuberculosis, especially miliary disease, should be considered as a possible etiology of fever of unknown origin. If the diagnosis of tuberculosis is highly suggestive, even without bacteriologic confirmation, a therapeutic trial of antituberculosis drugs should be given.