Fig. 19.

Mycobacterium avium-intracellulare infection: 17-year-old male patient with a known congenital immunodeficiency syndrome presented to ER with complaints of fever, malaise, chest pain, and left upper quadrant abdominal pain. a Chest CT showed bronchiectasis (arrows), mucus plugs, and centrilobular nodules in the lower lobes. Note was also made of airspace consolidation and volume loss in the right middle lobe and lingula (asterisks). Imaging findings were found to be suggestive of pulmonary atypical mycobacterial infection. b Axial plane T2W abdominal MR image of the same patient demonstrated multiple nodular hypointense lesions of varying sizes within the spleen (arrowheads). c In dynamic postcontrast MRI images with hepatospecific contrast agent, these lesions were hypoenhancing in the early phases. However, the signal intensity difference between the lesions and background splenic parenchyma gradually decreased in later phases (arrows). The lesions were more hyperintense than the splenic parenchyma in the hepatobiliary phase (arrows), possibly due to their fibrotic nature causing delayed contrast retention. With these imaging findings, splenic granulomas due to the atypical mycobacterial infection were considered. Sputum culture and PCR confirmed Mycobacterium avium-intracellulare complex infection, and the patient was treated accordingly