Prospective Evaluation of Taste Function In Multiple Myeloma Patients Undergoing Autologous Hematopoietic Cell Transplantation

Whole mouth microbiota will be assessed by having participants swish in their mouth 10 ml of sterile water for 30 sec and then expectorate in a sterile container. Specimens will be immediately placed on wet ice and transferred to the laboratory for processing or for storage at -80° C until they are ready to be prepared for sequencing.

Chemical gustometry assessments will be performed by a trained clinician on the study team, including a Registered Dietitian, Physician's Assistant, or Research Nurse. The test solutions and gradients will be formulated in house using sterile water and the following constituents: Sweet taste; 0.05, 0.1, and 0.2 g/ml sucrose, sour taste; 0.05, 0.09, and 0.165 g/ml citric acid, salty taste; 0.016, 0.04, and 0.1 g/ml NaCl and bitter taste; 0.0004, 0.0009, and 0.0024g/ml quinine-HCl. Umami will be tested with MSG at 25, 50, and 75 mM.

Both stimulated and un-stimulated salivation will be assessed by saliva collection in pre-weighed plastic containers. Participants will be seated with their back at a 90 degree angle and asked to swallow everything in their mouth. They will then be asked not to swallow and spit the accumulated saliva in the plastic container every 30 seconds for two minutes (unstimulated flow). For measurement of stimulated saliva, we will follow the same procedure except that after the initial swallow, participants will have their tongue swabbed twice with a cotton swab dipped in ascorbic acid solution or lemon juice.

Surveys will be administered and examine taste disturbances pre and post HCT.