Complicated pulmonary interstitial emphysema.

A 6-year-old boy with known acute lymphocytic leukemia was referred for radiologic evaluation of his complaints of newly onset cough, high fever, dsypnea and general situation worsening. The patient underwent invasive mechanical ventilation through an endotracheal tube in the intensive care unit. The patient's symptoms resolved within 7 days of initiating therapy and he was extubated, however left axillary crepitation and left side chest pain began. HRCT examination revealed irregular-shaped air spaces along the medium sized bronchovascular sheaths noted in the apices of both lungs (pulmonary interstitial emphysema) with localised pneumothorax in the left upper thorax and subcutaneous emphysema in the left axillary region additional to the diminished patchy ground-glass opacities (Fig. A, B). Most of these free air spaces were along the bronchovascular sheaths measured less than 1 cm in diameter. Pleural effusion and pneumomediastinum was not present in limited HRCT examination. There was marked clinical improvement at three-weeks follow-up. HRCT (Fig. C) done at the time of the three-weeks follow-up visit showed significant resolution of the pulmonary opacities and free air of the interstitium and subcutaneous tissue.