Echinococcus multilocularis and other zoonotic helminths in red foxes (Vulpes vulpes) from a southern German hotspot for human alveolar echinococcosis.

BACKGROUND: We describe the spatial distribution of Echinococcus multilocularis in its main definitive host, the red fox, and the distribution of human cases of alveolar echinococcosis (AE) within a highly endemic focus in southern Germany (13.7-19.9/100,000 in 1992-2018). Human cases were unequally distributed within the endemicity focus. The purpose of the study was to test whether this is reflected in the small-scale distribution of E. multilocularis in foxes. METHODS: Three areas with contrasting numbers of human cases were selected within the counties of Ravensburg and Alb-Donau, Baden-Württemberg, Germany. From 2018 to 2020, a total of 240 fox carcasses were obtained from traditional hunters in these areas. Carcasses were necropsied and examined for the presence of intestinal helminths. The statistical analysis was performed with SAS version 9.4, and the geo-mapping with QGIS version 3.16.0 Hannover. RESULTS: The prevalence of E. multilocularis in foxes was 44/106 (41.5%) in area I (commune Leutkirch and environs), 30/59 (50.8%) in area II (commune Isny and environs), and 31/75 (41.3%) in area III (commune Ehingen and environs). From 1992 to 2018, a total of nine human cases of alveolar echinococcosis were recorded in area I, five cases were recorded in study area III, and no cases were recorded in area II. No statistically significant differences between the areas were observed (P > 0.05) for intestinal infections with E. multilocularis, and no apparent spatial correlation with the small-scale distribution of human cases was found. Concerning other zoonotic helminths, Toxocara spp. were equally common, with prevalence of 38.7%, 47.4% and 48.0%, respectively, while the frequency of Alaria alata varied among the study areas (0.0-9.4%), probably reflecting the specific habitat requirements for the establishment of its complex life cycle. CONCLUSIONS: Echinococcus multilocularis is highly prevalent in foxes in all the studied areas. The varying number of human AE cases within these areas should therefore be caused by factors other than the intensity of parasite transmission in foxes.

Spleen and Liver Stiffness Evaluation by ARFI Imaging: A Reliable Tool for a Short-Term Monitoring of Portal Hypertension?

Background: Assessment of hepatic venous pressure gradient (HVPG) is the most reliable, though invasive method for evaluation of portal hypertension. Non-invasive, elastography-based techniques are well established in diagnosis, but not in monitoring of portal hypertension. The aim of our prospective study was to determine the value of acoustic radiation force impulse (ARFI) elastography technique of the liver and spleen in diagnosis and monitoring of portal hypertension. Methods: We prospectively assessed portal hypertension by HVPG and corresponding elastography of the liver and spleen in 31 patients with liver cirrhosis and an indication for primary prophylaxis by non-cardio selective beta-blockers. Investigations were performed at baseline and a follow-up visit after 6-8 weeks. To address the known large variability of values for spleen elastography, well-defined corresponding areas in the spleen were used for baseline and follow-up elastography. Sensitivity, specificity, and AUC-ROC values for both spleen and liver elastography monitoring of portal hypertension were calculated. Results: Liver but not spleen elastography significantly correlated with HVPG results and was suitable for initial evaluation of portal hypertension. However, changes in HVPG results did not show any correlation with alterations of ARFI values from baseline to follow-up visits both for liver and spleen elastography. Spleen stiffness results were not homogeneous across the whole organ differing significantly between the upper, hilar, and bottom placed investigation areas. Conclusions: In this prospective study ARFI-based assessment of liver elastography showed itself suitable for initial assessment but not for monitoring of portal hypertension. Spleen elastography was not appropriate for both, evaluation and monitoring of portal hypertension. A possible explanation for this new data that are in some contrast to previously published results is the degree of portal hypertension in our study, a comparatively short follow-up period, and well-defined investigation areas for spleen elastography in repetitive ARFI investigations. This trial is registered with NCT03315767.

Comparison of point and two-dimensional shear wave elastography of the spleen in healthy subjects.

BACKGROUND: Few systematic comparative studies of the different methods of physical elastography of the spleen are currently available. AIM: To compare point shear wave and two-dimensional elastography of the spleen considering the anatomical location (upper, hilar, and lower pole). METHODS: As part of a prospective clinical study, healthy volunteers were examined for splenic elasticity using four different ultrasound devices between May 2015 and April 2017. The devices used for point shear wave elastography were from Siemens (S 3000) and Philips (Epiq 7), and those used for two-dimensional shear wave elastography were from GE (Logiq E9) and Toshiba (Aplio 500). In addition, two different software versions (5.0 and 6.0) were evaluated for the Toshiba ultrasound device (Aplio 500). The study consisted of three arms: A, B, and C. RESULTS: In study arm A, 200 subjects were evaluated (78 males and 122 females, mean age 27.9 ± 8.1 years). In study arm B, 113 subjects were evaluated (38 men and 75 women, mean age 26.0 ± 6.3 years). In study arm C, 44 subjects were enrolled. A significant correlation of the shear wave velocities at the upper third of the spleen (r = 0.33088, P < 0.0001) was demonstrated only for the Philips Epiq 7 device compared to the Siemens Acuson S 3000. In comparisons of the other ultrasound devices (GE, Siemens, Toshiba), no comparable results could be obtained for any anatomical position of the spleen. The influencing factors age, gender, and body mass index did not show a clear correlation with the measured shear wave velocities. CONCLUSION: The absolute values of the shear wave elastography measurements of the spleen and the two different elastography methods are not comparable between different manufacturers or models.

Gallbladder stone incidence and prevalence in Germany: a population-based study.

BACKGROUND: We aimed to determine the prevalence and incidence of gallbladder stones in a random population-based collective in Germany. METHODS: We determined the prevalence and incidence rates of gallbladder stones in a random population sample of 1909 individuals from the Echinococcus-multilocularis in Leutkirch (EMIL) study in 2002 and 380 individuals in a follow-up analysis in the year 2013. The sonographic analysis was performed with a Philipps HDI 5000 (2002) and IU 22 (2013) (Netherlands) transducer 1-5 MHz. Statistical analysis was performed using SAS Version 9.4. RESULTS: The prevalence of gallbladder stones was 3.8 % (69/1909) in 2002 and 10.8 % (41/380) in 2013. In 2013, the gallbladder stone prevalence was 15.1 % (26/172) in women, compared to 7.2 % (15/208) in men. No gallbladder stones were found in participants in the 18-30 or 31-40 age groups. The average annual incidence was 1.03 % in the 41-50 age group, 0.79 % in the 51-65 age group, and 0.63 % in the > 65 age group. The annual incidence was higher among women (1.04 %) than men (0.53 %). The age-associated annual incidence rates for women and men were 1.93 % and 0.5 % in the 41-50 age group, 0.8 % and 0.78 % in the 51-65 age group, and 1.06 % and 0.30 % in the > 65 age group. CONCLUSION: For the investigated German collective from 2002 to 2013, the average annual incidence of gallbladder stones was 0.75 %, with a higher incidence rate among women. These results are consistent with data from comparable international studies.