Pediatric sialendoscopy: a 5-year experience at a single institution.

OBJECTIVES: To evaluate the outcome of our experience in the treatment of salivary gland disorders in children undergoing sialendoscopy and to assess the evolution of the technique. DESIGN: Retrospective medical record review. SETTING: Tertiary care university hospital. PATIENTS: Thirty-eight children with salivary gland disorders undergoing diagnostic and interventional sialendoscopy between January 1, 2003, and November 30, 2008. INTERVENTION: Diagnostic and interventional sialendoscopy using general anesthesia. MAIN OUTCOME MEASURES: Demographic, clinical, and surgical variables, including age, sex, date of first symptoms, parotid or submandibular location of disease, preoperative ultrasonographic results, sialendoscopy technique, sialendoscopy observations, and complications. RESULTS: Pediatric sialendoscopy was performed on the parotid gland in 23 patients (61%) and on the submandibular gland in 15 patients (39%). The most frequent indication for sialendoscopy was recurrent salivary gland swelling. Thirty-two of 38 procedures (84%) were performed endoscopically, whereas a combined intervention was necessary for 3 patients and a submandibular gland excision for another 3 patients. Sialendoscopy allowed the diagnosis of 12 patients with salivary duct lithiasis, 21 with salivary duct stenosis, and 2 with both submandibular lithiasis and stenosis, and findings from 3 sialendoscopies were normal. Preoperative ultrasonographic results were confirmed by sialendoscopy in only 7 patients. Of the 10 patients with lithiasis found using sialendoscopy, only 4 had been detected using preoperative ultrasonography. CONCLUSIONS: Sialendoscopy is a pertinent technique for the diagnosis and treatment of salivary gland disorders in children. It also allows the most conservative treatment of sialolithiasis and juvenile recurrent parotitis.

Purine-rich box-1-mediated reduced expression of CD20 alters rituximab-induced lysis of chronic lymphocytic leukemia B cells.

The anti-CD20 monoclonal antibody rituximab has been less successful in treating chronic lymphocytic leukemia (CLL) than lymphoma, possibly due to the lower density of CD20 on B lymphocytes from CLL patients than on those from lymphoma patients. This lowering may result from insufficiency of one of the transcription factors of cd20. Of these, purine-rich box-1 (PU.1) is poorly expressed in CLL. To estimate its weight in CD20 expression, pu.1 cDNA was transfected into CLL B cells and shown to raise the membrane expression of CD20 and to improve the rituximab-induced lysis of transfected cells. Granulocyte macrophage colony-stimulating factor and all-trans-retinoic acids were not involved in the defective expression of PU.1 or the excessive methylation of the pu.1 gene, because 6 of 14 CLL samples tested were normally methylated. This was confirmed by the failure of DNA methyltransferase inhibitors to restore pu.1 transcription in hypermethylated CLL, and, in fact, the expression of PU.1 was down-regulated by excessive expression of the FMS proto-oncogene-like tyrosine kinase 3 (Flt3) receptor. This abnormality is consistent with our finding of elevated levels of Flt3 ligand (FL) in 20 of 23 CLL sera tested. We propose that FL-dependent increased Flt3 signaling prevents the expression of PU.1, which down-regulates that of CD20, and accounts for resistance of leukemic B cells to rituximab-induced lysis.

Aberrant expression of BAFF by B lymphocytes infiltrating the salivary glands of patients with primary Sjögren's syndrome.

OBJECTIVE: To identify the cells that produce BAFF in the salivary glands of patients with primary Sjögren's syndrome (SS), and to analyze BAFF receptor expression by local T and B lymphocytes. METHODS: We used 3 methods to identify the source of BAFF: in situ hybridization of the transcripts for BAFF combined with staining of membrane markers, regular and real-time reverse transcription-polymerase chain reaction (RT-PCR) of cultured epithelial cells, and RT-PCR of sorted single-cell T and B lymphocytes eluted from salivary glands. Cells expressing TACI, BCMA, and B lymphocyte stimulator receptor 3 (BR-3) were disclosed by combining each specific staining of the receptors with each specific staining of the cells. The function of BAFF generated by epithelial cells on B lymphocytes was determined in short-term cocultures. RESULTS: Transcripts for BAFF were seen in epithelial cells and infiltrating T lymphocytes and, for the first time, were detected in local B cells. It is interesting that BR-3 was present on these B cells but not on T cells. In contrast, TACI and, to a lesser degree, BCMA were observed on transitional B lymphocytes, whereas T lymphocytes were devoid of receptors for BAFF. Furthermore, this cytokine was shown to be functional, in that epithelial cell-bound BAFF extended the survival of normal B cells, but cell-free BAFF released in the supernatants did not. CONCLUSION: These experiments establish that in primary SS, BAFF is produced not only by epithelial cells and T cells but also by B cells. The expression of receptors for BAFF would thus allow these receptors to participate in an autocrine pattern of self-stimulation.

Identification of transitional type II B cells in the salivary glands of patients with Sjögren's syndrome.

OBJECTIVE: To identify B cell subpopulations participating in the lymphocyte infiltrate of salivary glands from patients with primary Sjögren's syndrome. A special emphasis was placed on those B lymphocytes included in the ectopic germinal centers (GCs). METHODS: The presence of B cells in salivary glands and their polyclonality were ascertained by phenotyping and reverse transcription-polymerase chain reaction in salivary gland samples from 18 patients. Their phenotype was thoroughly analyzed using a number of double-staining combinations. The results obtained in tissue sections were confirmed by fluorescence-activated cell sorting analysis of B cells eluted from salivary glands, and these findings were compared with those in tonsils. RESULTS: Memory-type B cells were defined as CD20+, CD27+ and were seen in all specimens, whereas GCs were found in only 7 specimens. Furthermore, B cells found in these GCs lacked certain characteristics of centroblasts and centrocytes. Instead, they fulfilled the criteria for transitional type II (TII) B cells and resembled marginal-zone B cells. BAFF (the assistance of which is required for proper transformation of transitional TI B cells into transitional TII B cells) accumulated adjacent to transitional and marginal-zone-like B lymphocytes. Further evidence for the involvement of BAFF came from the expression of its receptors on infiltrating B cells. CONCLUSION: These transitional TII and marginal-zone-like B cells are probably instrumental in the local production of autoantibodies and possibly influential in the ensuing destruction of epithelial cells.