High-resolution CT in renal transplant patients with suspected pulmonary infections

This prospective study was carried out to assess the usefulness of high-resolution CT (HRCT) of the chest in immunocompromised renal transplant patients with suspected pulmonary infections.

Twenty-one consecutive renal transplant patients with clinically suspected pulmonary infections underwent chest radiography, HRCT and other tests including bronchoalveolar lavage (BAL). HRCT was performed using a high spatial frequency algorithm with 2-mm-thick sections at 10-mm intervals from apices to domes of the diaphragm. The findings on chest radiography and HRCT were interpreted by two thoracic radiologists and the usefulness of HRCT was evaluated. The images were interpreted independently by two radiologists, who were blinded to the findings of other imaging modalities and the final diagnosis. Any differences regarding the imaging findings were resolved through consensus.

Final diagnosis was obtained in 17 patients, and no cause for symptomatology was established in 4 patients. The spectrum of infections included pulmonary tuberculosis (TB) in 11 patients, cytomegalovirus pneumonia (CMV) in 2 patients, cryptococcal and streptococcal pneumonia, pulmonary aspergillosis and esophageal candidiasis in 1 patient each. Compared to chest radiography, HRCT revealed additional findings in 11 patients. HRCT findings were suggestive of underlying infection in 11 patients. The final diagnosis coincided with HRCT diagnosis in all but 1 patient. HRCT findings were non-specific in 3 patients and normal in 7. The findings were concordant in 19 cases. The results were not in agreement in only 2 cases.

HRCT can provide useful information and suggest the diagnosis in a significant proportion of renal transplant patients with pulmonary infection.