Table 1.
Patient demographics.
Fig 1.
Three PET/CT scans performed in a female patient with a large hepatic manifestation of alveolar echinococcosis.
The patient (patient 04 in Table 2) was 24 years old in 2005 (maximum intensity reconstructions of PET (A) and fused PET/CT images (D)), 32 years old in 2012 (B and E), and 40 years old in 2020 (C and F). She was treated with albendazol since 1997 and therapy was ongoing at the last clinical follow-up in 2021. In 2005, PET/CT showed moderate metabolic activity (A and D), EgHF AU were 58. In 2012, the patient presented with fever and was diagnosed with cholangitis and subsequently treated with antibiotics—PET/CT showed intense metabolic activity in the periphery of the echinococcosis manifestation (B and E), EgHF AU were lower than in 2005 (i.e., 46). In 2020 (C and F), PET/CT again showed moderate metabolic activity to a lesser extent, EgHF AU were 13. The large discrepancy in trends in this case, may indicate, that metabolic activity and EgHF antibody levels may have to be evaluated independently, when treating patients with alveolar echinococcosis.
Fig 2.
Two PET/CT scans performed in a male patient with a hepatic manifestation of alveolar echinococcosis involving the chest wall.
The patient (patient 09 in Table 2) was 55 years old in 2008 (maximum intensity reconstructions of PET (A) and fused PET/CT images (C)), and 58 years old in 2011 (B and D) and was treated with mebendazole from 2001 to 2011. The follow-up PET/CT 2011 (B and D) documented progression of disease with increasing involvement of the chest wall as compared to the PET/CT from 2008 (A and C) (EgHF AU increased from 34 to 35, SUVratio liver was continuously high at 4.6), and therapy was subsequently changed to albendazole. The patient died in 2017 of unknown cause.
Fig 3.
The graphs display the courses of EgHF antibody units and SUVratio liver over time in all 16 included patients with alveolar echinococcosis.
Table 2.
Quantitative PET/CT and outcome data of all included patients with inoperable alveolar echinococcosis.
Fig 4.
The graph displays linear regression (green line) and 95% confidence intervals (grey curves) of the SUVratio liver (highest metabolic activity of an echinococcosis manifestation divided by metabolic background activity in normal liver tissue) and EgHF antibody units. A significant correlation of both variables was found (p < 0.001).
Fig 5.
The graph displays linear regression (green line) and 95% confidence intervals (grey curves) of the difference (i.e., delta) of SUVratio liver in echinococcosis manifestations between two PET/CT examination of the same patient and the delta of EgHF antibodies in the respective time intervals. Overall, a significant correlation of both variables was found (p = 0.01). When comparing, patients on continuous benzimidazole therapy (blue dots) to patients without continuous treatment (red squares), no significant difference was determined.