Hepatic alveolar echinococcosis: correlation between computed tomography morphology and inflammatory activity in positron emission tomography

Abstract

Positron emission tomography-computed tomography (PET-CT) with 18F-fluorodesoxyglucose (FDG) is the imaging modality of choice for assessing inflammation surrounding hepatic alveolar echinococcosis (AE) lesions. This study is the first to evaluate FDG uptake in hepatic AE (n = 51) based on the standardized uptake value (SUV) and to correlate the SUVs with primary morphology and calcification patterns, based on the Echinococcus multilocularis Ulm Classification for Computed-Tomography (EMUC-CT). Our results show that the SUVs were increased for lesions with EMUC-CT types I-IV primary morphology, compared to the surrounding healthy liver tissue (SUV = 2.5 ± 0.4; p < 0.05). Type IV lesions included, by far, the highest number of PET-negative lesions. A comparison of lesions with different primary morphologies showed clear differences. The highest SUVs were found for types I and III, and the lowest was found for type IV. Type IV lesions (SUV, 3.8 ± 1.5) showed significantly lower uptake compared to type I (SUV, 6.9 ± 3.5; p = 0.030) and type III (SUV, 7.4 ± 3.9; p = 0.031) lesions. For type II lesions, the results showed only a statistical trend (SUV, 6.1 ± 3.1; p = 0.073). Due to the small number of cases, an evaluation of type V (n = 1) lesions was not possible. The different SUVs of lesions with different primary morphologies, particularly the lower FDG uptake observed in type IV lesions, suggested that these SUVs might reflect different stages of the disease. prevalence. Alveolar echinococcosis (AE) is a dangerous zoonosis caused by the fox tapeworm, Echinococcus multilocularis. E. multilocularis is predominantly found in the cooler, temperate latitudes of the northern hemisphere 1,2. Europe, particularly southern Germany, eastern France, northern Switzerland, and western Austria, are heavily populated with the parasite 1-3. Outside central Europe, many human cases of AE have been found in China, particularly in the Tibetan plateau, and in Russia, particularly Siberia 1,2,4,5. Most human cases of AE were reported in China 1,6-10. General clinical picture and diagnosis. In over 98 percent, the liver is the organ most affected by AE.

Combining Computed Tomography and Histology Leads to an Evolutionary Concept of Hepatic Alveolar Echinococcosis

“…The sequential lesion evolution will then be taken into account by a corresponding adapted sequence of the numbered lesion types. Recently published studies regarding epidemiological CT data from Europe and China, as well as the analyses of different CT morphological types concerning their density and their activity in positron emission tomography further support this hypothesis of an evolutionary model in hepatic AE lesions [ 31 , 32 , 33 ].…”

Echinococcus multilocularis specific antibody, systemic cytokine, and chemokine levels, as well as antigen-specific cellular responses in patients with progressive, stable, and cured alveolar echinococcosis: A 10-year follow-up

“…Ultrasound (US) and computed tomography (CT) were used to confirm alveolar echinococcosis [ 1 ], and magnetic resonance imaging (MRI) can provide a more differentiated diagnosis, to identify blood vessel structures before surgery [ 3 , 30 ]. Positron emission tomography (PET) or combined PET-CT was used to shows areas of high metabolic activity, which may indicate inflammatory reactions and possible activity of the parasite [ 31 ].…”

Stage-Oriented CT Classification and Intermodal Evolution Model in Hepatic Alveolar Echinococcosis

“…The evolution of the lesion morphologies is presented in consideration of the most important intermodal aspects (▶ Fig. 5a) [17,[22][23][24][25][26][27][29][30][31]: ▶ Fig. 4 Structured reporting form based on the AEUC.…”