[Trichinella induced polymyositis with unilateral lameness in a dog]. / Polymyositis mit einseitiger Lahmheit im Rahmen einer Trichinellose beim Hund.

A 9-year-old Cairn Terrier was presented for a right thoracic limb lameness of 3-month duration resistant to anti-inflammatory pain treatment. Blood chemistry revealed a highly elevated creatine kinase activity. An orthopedic or vascular etiology of the lameness was excluded by radiographs, computed tomography, and magnetic resonance imaging. Further workup for a neurologic or muscular etiology by electromyography, nerve conduction velocity measurement, and histology of muscle as well as nerve biopsies identified the cause of the lameness. Histology revealed a pyogranulomatous, necrotizing myositis with parasites of the species Trichinella. Furthermore different developmental stages of fungi were detected which were identified as Mucor sp. Treatment with albendazole and itraconazole significantly improved the patient's clinical signs.

Assessment of local reaction to vaccines in live piglets with magnetic resonance imaging compared to histopathology.

The safety of veterinary vaccines is assessed in clinical trials in Europe. The assessment of the local tissue reaction to vaccination by magnetic resonance imaging (MRI) could reduce the number of animals needed because repeated examinations can be performed in the same animal over time. The present study compared the evaluation of local tissue reactions to vaccination using MRI in live pigs with histopathology of porcine tissue, the current gold standard in regulatory safety testing. Eight piglets each were administered one of two commercial vaccines into marked injection sites. All animals were sedated and scanned repeatedly by MRI using a contrast agent up to day 29 after vaccination. On day 29, the animals were euthanized and underwent a pathological examination. The MRI results were compared with the pathomorphological findings at the injection site by regression analysis. The MR images and the pathological examinations yielded matching results concerning the sizes of the affected tissue volumes or areas. The use of MRI for regulatory safety testing can reduce the number of animals needed to 8 per examination group. The volume of a local reaction and its progression over time can be evaluated and documented. If persistent lesions develop a final pathomorphological examination is needed to identify the kind and local distribution of the reaction.

Value of histopathology, immunohistochemistry, and real-time polymerase chain reaction in the confirmatory diagnosis of Encephalitozoon cuniculi infection in rabbits.

Morphological lesions in kidneys and brain are all too often considered diagnostic for confirmation of encephalitozoonosis in rabbits. The current study evaluated the diagnostic value of histology versus other etiological tests, including immunohistochemistry and real-time polymerase chain reaction (PCR) for Encephalitozoon cuniculi infection diagnosis. Samples of brain, heart, lungs, intestine, liver, and kidneys from 81 rabbits were examined for morphological lesions attributed to E. cuniculi infection as well as for the presence of spores and E. cuniculi antigen. Of these, 55 rabbits were tested for E. cuniculi DNA. Histological changes consistent with E. cuniculi infection were seen in 33 rabbits (41%, 33/81) representing 87% (33/38) of all rabbits with confirmed E. cuniculi infection. Brains of these rabbits displayed 6 different types of focal lesions corresponding to the stage of infection and specific tissue response. In 5 rabbits that were tested positive, histology was either inconclusive or inconspicuous. Etiological diagnosis was based on histological spore detection in 16% (6/38) of infected rabbits. Immunohistochemistry was more sensitive (42%, 16/38) than histological spore detection, and real-time PCR proved to be the most sensitive of all investigated methods (30/35, 86% of the examined rabbits with E. cuniculi infection). Encephalitozoon cuniculi infection rarely occurs without characteristic kidney and brain lesions. However, the spectrum of brain changes is wider than previously reported. Based on these findings, confirmation of pathogenic E. cuniculi infection should include standard histology of the predilection sites and a specific etiological assay, preferably real-time PCR.