Post-allogeneic Hematopoietic Stem Cell Transplantation (HSCT) changes in inorganic salivary components.

Recent studies have considered the qualitative and quantitative assessment of salivary flow, as well the biochemical components of saliva, as possible biomarkers that might contribute to the pathogenesis of chronic graft-versus-host disease (cGHVD) in hematopoietic stem cell transplantation (HSCT) patients. The aim of this study was to evaluate prospectively the inorganic salivary status at different periods of allogeneic HSCT. Saliva collection and oral examination were performed prior to the HSCT, ​between days 8 and 10, days 80 and 100, and at the cGVHD onset. Concentrations of calcium (Ca), phosphate (Pi), chloride (Cl), magnesium (Mg), potassium (K), and sodium (Na) were performed using colorimetric reactions and atomic absorption. Fifty-five consecutive patients undergoing first allogeneic HSCT were included in this study. Between days 8 and 10, the salivary flow rate was significantly higher (p = 0.05), Pi concentration was decreased (p = 0.007), and Na and Cl were increased (p = 0.001 and p = 0.001, respectively), compared with the baseline. Salivary flow rate during the same period showed a negative correlation with Pi concentration (p = 0.02) and a positive correlation with Na and Cl concentrations (p = 0.003 and p = 0.001, respectively). The salivary flow rate was decreased between days 80 and 100 (p = 0.02) and Na, Cl, and K concentrations were increased (p = 0.03, p = 0.02, and p = 0.003, respectively). Salivary flow rate showed a negative correlation with Na and Cl (p = 0.01 and p = 0.013, respectively). At cGVHD onset, the salivary flow rate showed no statistical difference compared with the other studied periods. A trend was observed in the higher Na concentration compared with the baseline (p = 0.06) and Pi concentration presented a significant decrease (p = 0.004). Ca and Mg concentrations showed no changes during all evaluation periods. The present study showed changes in inorganic salivary components in post-HSCT periods, mainly during the early period post-HSCT and at the cGVHD onset. We speculate that Na, Cl, and Pi in saliva could be used as a potential biomarker in further studies.

Taste disorders and oral evaluation in patients undergoing allogeneic hematopoietic SCT.

The aim of this study was to evaluate taste perception, salivary flow rate and oral pathologies in three different groups of patients undergoing hematopoietic SCT (HSCT) classified according to time post transplant. Group I (n=20) up to 150 days after HSCT, group II (n=20) between 151 and 1095 days and group III (n=21) more than 1095 days. Taste acuity was measured by four basic tastes of four solutions, in three concentrations (M): NaCl, sucrose, citric acid and caffeine. Patients classified flavors as sweet, sour, salty, bitter and without flavor. The intensity was considered high, medium and low. Unstimulated saliva was collected and salivary flow rates (ml/min) were determined. Of 61 patients, 31 had chronic GVHD. For the sweet solution, the high and low concentrations represented a challenge for those patients. No patients were sensitive to the low concentration of caffeine solution (P=0.05). Saliva flow rate was diminished in 10 of 61 (16%) patients and hyposalivation was more intense in groups II/III (P=0.007). There was no correlation between taste dysfunction and oral chronic GVHD. The results indicated taste alterations only for the sweet and salty tastes even in patients up to 3 years after HSCT and may not correlate with oral chronic GVHD and with hyposalivation.