Clinical, histopathological and immunohistochemical investigations of chronic sialectatic parotitis in children and juveniles

Chronic sialectatic parotitis (CSP) causes problems in differential diagnos is and therapy. CSP shows the typical clinical features of chronic recurren t parotitis and will be investigated histopathologically only after ultimat ive parotidectomy. The etiology and pathogenesis of these unspecific inflam mations is still unknown. Therefore no causal therapy is available and a lo t of different trials (sialogoga, gland massage, infrared light, antibiotic s, antiphlogistics, Trasylol(R), duct occlusion, duct ligation, gland dener vation, radiotherapy) are not successful in the-long run. Material and method: The salivary gland registry of the University of Hambu rg (1965-1996) contains 22 infants and juvenile patients showing very sever e courses of CSP. These cases have been investigated clinical (ultrasound, sialography), histopathological (paraffin embedded sections, histomorphomet ry of the ectatic duct lumina) and immunohistochemical (CK-MNF, AKTIN, KiM4 ) in a retrospective study to research the pathogenesis of CSP. Results: Recurrent and always very dolent parotid swelling occurs between t he age of 3 and 14 years for the first time. The courses vary from 3 months until 25 years. Local findings as well as ultrasound and sialographic feat ures allow no certain differentiation of chronic recurrent parotitis. Conse rvative therapy fails in each case and leads to the necessity of surgical t reatment. Histopathological three different stages of development can be ob served: Initial stages show regular lobular architectonic structure of the parotid gland parenchyme with duct ectasies surrounded by slight inflammati on of lymphocytes and plasmacells. Advanced stages are characterized by an increase of periductal inflammation and the appearance of lymphfollicels. N early complete lymphatic transformation of the parenchyme with destruction of the lobular formation dominates the terminal "immunologic" stage. Some c ases show multiple myoepithelial islands within this lymphatic stroma typic ally observed in benign lymphoepithelial lesions. Whether bacteria nor prim ary obstructive changes can be observed. The histomorphometric analyses of the average and maximal luminal duct diameters show marked increase of 39% respectively 46% from advanced to terminal stages of CSP. Therefore the pat hognomonic duct ectasies seem to depend on the progredient inflammation and are not due to a hereditary malformation of the duct system. Immunohistoch emical terminal stages show follicular lymphatic hyperplasia (KiM4) express ing overshooting humoral immune reaction of MALT. Conclusion: Concerning the pathogenesis CSP corresponds to a immunopatholog ical disorder of MALT and seems to be a prestage of benign lymphoepithelial lesion. Consequently important changes in the diagnosis and therapy of CSP lead to early histopathological investigation to differentiate the stage o f inflammation. In stage III conservative parotidectomy should be carried o ut because spontaneous healing can nor be expected. In contrast initial cas es should be treated at first by glucocorticoids and immunosuppressives.