Objective: To determine the correlation between pH and bicarbonate of soda in blood and saliva in child and adolescent patients during the administration of 3 g/m2 of methotrexate.
Method: A controlled clinical test was performed on 23 patients diagnosed with Acute Lymphoblastic Leukemia. Ages ranged from 4 to 18. The Spearman Correlation Coefficient was used to interpret the data.
Results: No significant correlation was found between pH levels and seric and salivary sodium bicarbonate. However, there was a significant correlation between the levels of sodium bicarbonate in the body fluids evaluated (rs 0.2576, p=0.0354).
Conclusions: Changes modifying the microenvironment of the oral cavity probably do not allow saliva to be used to determine blood pH and seric bicarbonate.