Miliary tuberculosis resulting in adult respiratory distress syndrome: a surviving case

An interesting case summary of tubercular pneumonia masquerading as viral pneumonia kept on extra-corporeal membrane oxygenation

Mortality in patients with pulmonary tuberculosis remains high, especially in those who develop acute respiratory distress syndrome (ARDS). We herein, report a case of 40 year old female, with ARDS due to severe pulmonary tuberculosis. She was admitted in the intensive care unit of a tertiary care centre. Owing to very poor ABG report, she was intubated and put on Mechanical ventilator support. Bronchoscopy was performed and BAL was extracted, which showed no growth. Further deterioration of gas exchange prompted the decision to put her on ECMO. During her stay on ECMO, she developed massive inta-alveolar hemorrhage following which repeated bronchoscopic interventions were done to remove blood clots. BAL extracted on day 4 and day 8 showed growth of A. baumannii and K. pneumoniae respectively. But BALGeneXpert on day 8 came out to be positive for Mycobacterium Tuberculosis and subsequently ATT was added to her treatment regimen. Her alveolar hemorrhage continued to worsen and subsequently ECMO was removed. After 12 days of hospitalization, she went on to develop bradycardia and could not be rescued. Though the patient's life was lost, this case provided many insights on the use of ECMO in the management of ARDS due to Pulmonary tuberculosis and it should be considered as one of the treatment options.

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.

High resolution CT findings of miliary tuberculosis

PURPOSE

The purpose of this study was to analyze high resolution CT (HRCT) findings of miliary tuberculosis and to assess the clinical utility of HRCT in the management of patients with miliary tuberculosis.

METHOD

We reviewed retrospectively HRCT scans of 25 patients with histopathologically (n = 16) and/or microbiologically (n = 9) proven miliary tuberculosis.

RESULTS

HRCT scans showed miliary nodules in 24 patients, which varied in size from 1 to 5 mm, with either sharply (n = 21) or poorly (n = 3) defined margins. The nodules had diffuse random distribution throughout both lungs and within the secondary pulmonary lobules. In 23 patients, areas of ground-glass opacities (GGOs) were observed with variable extent and distribution. The patients who had dyspnea showed large areas of GGOs, and two patients with impending adult respiratory distress syndrome revealed extensive GGOs. Both intralobular reticulation and interlobular septal thickening were seen in 10 patients.

CONCLUSION

Miliary nodules and GGOs are the predominant HRCT findings in patients with miliary tuberculosis, and HRCT scans are helpful in the early diagnosis and proper management of patients with miliary tuberculosis.

CT of pulmonary tuberculosis

CT scans in patients with primary tuberculosis commonly show lymphohematogenous spread of the disease, whereas those of postprimary (reactivation) tuberculosis commonly show bronchogenic spread. High-resolution CT (HCRT) is extremely helpful in understanding pathomorphological changes, mode of spread of the disease, and sequential morphological change after antituberculous chemotherapy, and possibly in diagnosing activity of the disease. Centrilobular 2- to 4-mm nodules or branching linear lesions representing intrabronchiolar and peribronchiolar caseation necrosis are the most common findings of early bronchogenic spread of tuberculosis. The 2- to 4-mm centrilobular nodules may coalesce to form 5- to 8-mm nodules or lobular consolidation. Cavitation usually begins at the central portion of a lobule around the bronchioles. Resolution of the tuberculous lesions occurs with antituberculous chemotherapy, resulting in varying degrees of fibrosis, bronchovascular distortion, emphysema, and bronchiectasis. HRCT may show both paracicatricial irregular emphysema and lobular emphysema. CT findings of early miliary dissemination commonly include ground-glass opacification with barely discernible nodules that show discrete miliary nodules thereafter. CT also is useful in the evaluation of long-standing destructive pulmonary lesions and tracheobronchial tuberculosis.

A common denominator in the etiology of adult respiratory distress syndrome

The initiating factor in ARDS is a matter of controversy. Some investigators relate ARDS development to diffuse pulmonary microemboli after stress ranging from sepsis to non-thoracic and thoracic trauma. Others indicate hyperoxic exposure as the causative agent. This investigation looked for a common factor in ischemia and hyperoxic exposure in lung which could cause the genesis of ARDS. Studies of oxidative phosphorylation, succinate dehydrogenase activity and ATP level were performed on ischemic and 100% O2 exposed lung. Results in both showed decreased respiration rate below the basal rate, decreased SDH activity, followed by marked decrease in ATP levels in pulmonary tissue. Decrease in respiration (ATP production) capacity and ATP levels in ischemic lung were such that normal cell functions could not be sustained if returned to normal circulation. Hyperbaric O2 therapy would subsequently decrease energy metabolism in regions of normal circulation and in previously ischemic regions.