ABSTRACT
The oral cavity commonly displays mucosal lichenoid lesions and salivary gland dysfunction, which are considered different chronic Graft-versus-Host Disease (cGVHD) pathophysiology's. However, diagnostics of salivary gland (sg-)cGVHD are limited. The objectives of the current study are to evaluate the minor salivary gland (MSG) histo-immunopathological profiles post allogenic hematopoietic cell transplantation based on sg-cGVHD criteria. Design: Histopathology was characterized according to two published grading strategies. Firstly, the National Institute of Health (NIH) assessed peri-ductal/acinar infiltration, exocytosis, damage, and fibrosis, and a points-based grading scheme was established (0-16 points, Grade (G) 0 to IV). Second, a modified Sjögren's Syndrome focus-score with parenchymal damage was also adapted, (0-10 points, Score 0 to 2). 146 MSG biopsies from 79 patients were compared, using the histopathological specific criteria for sg-cGVHD pathology. Quantitative immunohistochemistry for T-cells (CD4, CD8), B-cells (CD19, CD20), monocytic cells (CD68) and dendritic cells (CD1a) were also assessed. Results: The large-scale cohort validated the use of both grading schemes. GIII-GIV and score 2 signified a histopathological diagnosis of "likely" sg-cGVHD. Immunopathological severity was associated with increased T-cells (CD4 and CD8) and monocytic (CD68) infiltrate, with minimal involvement of B-cells (CD19 and CD20), and Langerhans cells (CD1a). Conclusions: Both schemes were verified as being suitable for histological grading to improve assessment and diagnosis of sg-cGVHD. The NIH cGVHD grading appears to be more beneficial for research purposes, including final diagnostics of "no/inactive", "possible" or "likely" cGVHD. The study highlights the intricacies of sg-cGVHD pathology; and the need for standardized assessment to improve patient management associated to sg-cGVHD.
ABSTRACT
CONCLUSION: The results of this study confirm that the present rabbit model of dental maxillary sinusitis (dMxS) is reproducible and simulates human dental sinusitis with respect to initiation, progression and inflammation. It is applicable to further studies of sinusitis of odontogenic origin. OBJECTIVES: To induce acute dMxS in rabbits by using their own oral microflora to create a periapical infection and to follow morphological, radiographic, bacteriological and histological changes to the sinus mucosa. MATERIAL AND METHODS: The experimental animals comprised 26 New Zealand White rabbits. Maxillary premolar root canals were identified bilaterally and the continuously growing germs of the roots were severed by diathermy. The animals were randomized into 2 groups: in Group 1 (n=20) the teeth were left open for the entire study period; in Group 2 (n=6) the root canals were sealed 1 week after the initial intervention. The animals in Group 1 were sacrificed at intervals ranging from 2 h to 9 months after intervention. All animals in Group 2 were sacrificed 6 months after intervention. After macroscopic and radiographic examination, post-mortem inspection of the paranasal sinus cavity and maxillary complex and microbiological sampling, the entire nasal sinus complex with the hard palate in situ was resected and processed for serial coronal sectioning. RESULTS: In Group 1, after 3 months, the radiographic changes ranged from widening of the periodontal space to bone reaction. At sacrifice, changes in the sinus mucosa ranged from signs of mucosal inflammation to purulent dMxS. Microbial growth, predominantly Gram-negative aerobes, increased over time. In Group 2, the findings were generally more pronounced. Anaerobic microorganisms were predominant. In both groups the findings were consistent with dMxS.
