Diffusion-weighted MRI in the follow-up of chronic periaortitis.

OBJECTIVE: To evaluate the usefulness of diffusion-weighted MRI (DWI) for the assessment of the intraindividual follow-up in patients with chronic periaortitis (CP) under medication. METHODS: MRI data of 21 consecutive patients with newly diagnosed untreated disease were retrospectively examined before and after medical therapy, with a median follow-up of 16 weeks. DWI parameters [b800 signal, apparent diffusion coefficient (ADC) values] of the CP and psoas muscle were analysed together with the extent and contrast enhancement. Pre- and post-treatment laboratory inflammation markers were acquired parallel to each MR examination. RESULTS: Statistically significant lower b800 signal intensities (p ≤ 0.0001) and higher ADC values (p ≤ 0.0001) were observed after medical treatment within the fibrous periaortic tissue. Extent and contrast enhancement of the CP showed also a statistically significant decrease (p ≤ 0.0001) in the follow-up examinations, while the control parameters within the psoas muscle showed no differences. CONCLUSION: DWI seems to be a useful method for the evaluation of response to treatment without contrast agents. The technique may be helpful in the assessment of disease activity to guide further therapeutic strategies. ADVANCES IN KNOWLEDGE: DWI detects significant differences in the intraindividual follow-up of CP under medical therapy.

Diffusion-weighted MRI in the follow-up of chronic periaortitis.

OBJECTIVE:: To evaluate the usefulness of diffusion-weighted MRI (DWI) for the assessment of the intraindividual follow-up in patients with chronic periaortitis (CP) under medication. METHODS:: MRI data of 21 consecutive patients with newly diagnosed untreated disease were retrospectively examined before and after medical therapy, with a median follow-up of 16 weeks. DWI parameters [b800 signal, apparent diffusion coefficient (ADC) values] of the CP and psoas muscle were analysed together with the extent and contrast enhancement. Pre- and post-treatment laboratory inflammation markers were acquired parallel to each MR examination. RESULTS:: Statistically significant lower b800 signal intensities (p ≤ 0.0001) and higher ADC values (p ≤ 0.0001) were observed after medical treatment within the fibrous periaortic tissue. Extent and contrast enhancement of the CP showed also a statistically significant decrease (p ≤ 0.0001) in the follow-up examinations, while the control parameters within the psoas muscle showed no differences. CONCLUSION:: DWI seems to be a useful method for the evaluation of response to treatment without contrast agents. The technique may be helpful in the assessment of disease activity to guide further therapeutic strategies. ADVANCES IN KNOWLEDGE:: DWI detects significant differences in the intraindividual follow-up of CP under medical therapy.

Hepatosplenic morbidity due to Schistosoma mansoni in schoolchildren on Ukerewe Island, Tanzania.

The study was conducted to assess infection intensity and morbidity due to Schistosoma mansoni in schoolchildren on Ukerewe Island in Lake Victoria, Tanzania, East Africa. Three hundred and sixty pupils who have never been treated previously were enrolled (180 males/180 females, age 6-17 years [median 10 years]) in three different schools of the island. Double stool samples were collected from each pupil and egg excretion was classified according to WHO recommendations. Ultrasound investigations were performed in accordance with the WHO Niamey-Belo-Horizonte protocol. Male (112/180, 62.2%) and female (104/180; 57.7%) pupils were infected (difference, not significant [n.s.]). In the positive 216 cases, egg excretion varied from 1 to 2,440 eggs per gramme stool (epg) [median 165 epg]. There were 69/216 (31.9%) who had a low grade, 105/216 (53.2%) had a moderate and 42/216 (14.8%) had a heavy infection. There was no significant difference between male and female sex nor with regard to age groups. There were 354/360 children who underwent sonography: 321 (90.7%) had splenomegaly, 316 (89.3%) showed a left lobe and 109 (30.9%) had a right lobe hepatomegaly. Overt signs of portal fibrosis (PF) were present in 19 children (5.4%) out of whom 11 presented with echogenic thickening of peripheral portal and 8 with thickening of central portal branches. Non-specific portal wall changes were seen in 6 children (1.7%). Association of PF to quantitative egg excretion was not seen (median in PF, 172 epg vs. median in non PF, 168 epg; difference, n.s.). Portal vein dilatation was seen in 101/354 (28.5%) cases. In Ukerewe, the prevalence of S. mansoni infection and infection intensity in children is high, yet overt hepatic morbidity is low as compared to other endemic foci. Non-specific ultrasonographic abnormalities including hepatosplenomegaly and portal vein dilatation were seen frequently but the fraction attributable to schistosomiasis is difficult to assess.