Diffuse FDG uptake in the bilateral lungs: hypersensitivity pneumonitis supported by low-dose CT findings

Document Type : Case report

Authors

1 Department of Nuclear Medicine, Saitama Medical University International Medical Center, Saitama, Japan

2 Department of Respiratory Medicine, Saitama Medical University Hospital, Saitama, Japan

Abstract

Hypersensitivity pneumonitis (HP) is an interstitial lung disease resulting from an immune-mediated response in susceptible and sensitized individuals to various inhaled antigens in the environment. Imaging diagnosis is usually based on high-resolution CT findings. Here, we present a 49-year-old man with a history of diffuse large B-cell lymphoma presented with fever and occasional cough. 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) revealed diffuse FDG uptake in the bilateral lungs. Expiratory low-dose CT simultaneously performed in PET scanning revealed centrilobular nodules and air trapping in ground glass opacities (GGO). Our imaging diagnosis was acute hypersensitivity pneumonitis (HP). Based on the results of his clinical course, blood laboratory tests, and bronchoscopy, he was diagnosed with acute HP. Diffuse pulmonary FDG uptake can be seen in the patients with acute HP. In addition, expiratory low-dose CT findings of centrilobular nodules and air trapping in GGO may be helpful for accurate diagnosis of acute HP.

Keywords


  1. Costabel U, Miyazaki Y, Pardo A, Koschel D, Bonella F, Spagnolo P, et al. Hyper-sensitivity pneumonitis. Nat Rev Dis Primers. 2020; 6(1):65.
  2. Shiiba M, Izutsu K, Ishihara M. Early detection of intravascular large B-cell lymphoma by 18FDG-PET/CT with diffuse FDG uptake in the lung without respiratory symptoms or chest CT abnormalities. Asia Ocean J Nucl Med Biol. 2014; 2(1):65-8.
  3. Wu F, Wang Z, Xing X, Yu M, Shi B. The Value of 18F-FDG PET/CT in Diagnostic Procedure of Intravascular Large B-Cell Lymphoma Presenting Fever of Unknown Origin and Pulmonary Hypertension as an Initial Clin Nucl Med. 2016; 41(6): 506-7.
  4. Yamane T, Daimaru O, Ito S, Nagata T, Yoshiya K, Fukaya N, et al. Drug-induced pneumonitis detected earlier by 18F-FDG-PET than by high-resolution CT: a case report with non-Hodgkin's lymphoma. Ann Nucl Med. 2008; 22(8):719-22.
  5. Kazama T, Faria SC, Uchida Y, Ito H, Macapinlac HA. Pulmonary drug toxicity: FDG-PET findings in patients with Ann Nucl Med. 2008; 22(2):111-4.
  6. Prabhu M, Raju S, Chakraborty D, Arora S, Kumar R. Spectrum of 18F-FDG Uptake in Bilateral Lung Parenchymal Diseases on PET/CT. Clin Nucl Med. 2020;45(1):e15-e9.
  7. Win Z, Todd J, Al-Nahhas A. FDG-PET imaging in Pneumocystis carinii pneumonia. Clin Nucl Med. 2005; 30(10):690-1.
  8. ntriago B, Danus M, Calvo N, Escobar J, Montero M, Kohan S, et al. Influenza-like infection can result in diffuse fluordeoxy-glucose uptake in the lungs. Clin Nucl Med. 2009; 34(10):737-8.
  9. Silva CI, Churg A, Muller NL. Hyper-sensitivity pneumonitis: spectrum of high-resolution CT and pathologic findings. AJR Am J Roentgenol. 2007; 188(2):334-44.
  10. Patel RA, Sellami D, Gotway MB, Golden JA, Webb WR. Hypersensitivity pneumonitis: patterns on high-resolution CT. J Comput Assist Tomogr. 2000; 24(6):965-70.
  11. Selman M, Pardo A, King TE, Jr. Hyper-sensitivity pneumonitis: insights in diagnosis and pathobiology. Am J Respir Crit Care Med. 2012; 186(4):314-24.
  12. Nobashi T, Kubo T, Nakamoto Y, Handa T, Koyasu S, Ishimori T, et al. 18F-FDG Uptake in Less Affected Lung Field Provides Prognostic Stratification in Patients with Interstitial Lung Disease. J Nucl Med. 2016; 57(12): 1899-904.
  13. Hung BT, Wang PW, Su YJ, Huang WC, Chang YH, Huang SH, et al. The efficacy of 18F-FDG PET/CT and 67Ga SPECT/CT in diagnosing fever of unknown origin. Int J Infect Dis. 2017; 62:10-7.
  14. Matsusaka Y, Kawada I, Nakahara T, Iwabuchi Y, Kawaida M, Matsusaka M, et al. Abnormal Uptake and Air Trapping in Hypersensitivity Pneumonitis Detected on Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography. Am J Respir Crit Care Med. 2019; 200(12):1542-3.
  15. Rusinek H, Naidich DP, McGuinness G, Leitman BS, McCauley DI, Krinsky GA, et al. Pulmonary nodule detection: low-dose versus conventional CT. Radiology. 1998; 209(1):243-9.
  16. Karabulut N, Toru M, Gelebek V, Gulsun M, Ariyurek OM. Comparison of low-dose and standard-dose helical CT in the evaluation of pulmonary nodules. Eur Radiol. 2002; 12(11):2764-9.
  17. Jahangiri P, Pournazari K, Torigian DA, Werner TJ, Swisher-McClure S, Simone CB, 2nd, et al. A prospective study of the feasibility of FDG-PET/CT imaging to quantify radiation-induced lung infla-mmation in locally advanced non-small cell lung cancer patients receiving proton or photon radiotherapy. Eur J Nucl Med Mol Imaging. 2019; 46(1):206-16.
  18. Jacquelin V, Mekinian A, Brillet PY, Nunes H, Fain O, Valeyre D, et al. FDG-PET/CT in the prediction of pulmonary function improvement in nonspecific interstitial pneumonia. A Pilot Study. Eur J Radiol. 2016; 85(12):2200-5.