Correlation between breath ammonia and blood urea nitrogen levels in chronic kidney disease and dialysis patients

Abstract

Previous studies have shown that breath ammonia (breath-NH3) concentration is associated with blood urea nitrogen (BUN) levels. However, interindividual variations in breath-NH3 concentrations were observed. Thus, the present study aimed to assess the effect of oral cavity conditions on breath-NH3 concentration and to validate whether the measurement of breath-NH3 concentration is feasible in clinical settings. A total of 125 individuals, including patients with stage 3 to 5 chronic kidney disease (CKD3–5), those on dialysis, and healthy participants, were recruited. A nanostructured sensor was used to detect breath-NH3 concentrations. Pre- and post-gargling as well as pre- and post-hemodialysis (HD) breath-NH3, salivary pH, and salivary urea levels were measured. Breath-NH3, salivary urea, salivary pH, and BUN levels were positively correlated to each other. Breath-NH3 concentrations were associated with BUN levels (r = 0.43, p < 0.001) and were significantly higher in CKD3–5 (p < 0.005) and dialysis patients (p < 0.001) than in healthy participants. Higher correlation coefficients were noted between breath-NH3 concentrations and BUN levels during follow-up (r = 0.59–0.94, p < 0.05). When the cutoff value of breath-NH3 was set at 523.65 ppb, its sensitivity and specificity in predicting CKD (BUN level >24 mg dl−1) were 87.6% and 80.9%, respectively. Breath-NH3 concentrations decreased after HD (p < 0.001) and immediately after gargling (p < 0.01). Breath-NH3 concentration, which was affected by gargling, was correlated to BUN level. The measurement of breath-NH3 concentration using the nanostructured device may be used as a tool for CKD detection and personalized point-of-care for CKD and dialysis patients. The current study had a small sample size. Thus, further studies with a larger cohort must be conducted to validate the effect of oral factors on breath-NH3 concentration and to validate the benefit of breath-NH3 measurement.

Micrometer-Scale Grating Vertical Structure OSC Ammonia Gas Sensor with a PEDOT:PSS Coupling Layer Using the Current Spreading Effect to Achieve ppb-Regime Sensing Capability

“…Now, we like to study the micrograting sensor performance by using the other OSC material. Poly­[(4,8-bis­(2-ethylhexyloxy)-benzo-(1,2- b :4,5- b ’)­dithiophene)-2,6-diyl- alt -(4-(2-ethylhexyl)-3-fluorothieno­[3,4- b ]­thiophene)-2-carboxylate-2,6-diyl)] (PTB7) is an OSC material that is one of the most prominent materials in the area of organics and polymer solar cell studies and applications. − Recently, PTB7 has been reported in our prior works to serve as an ammonia sensor with good air stability , but is not widely used in the gas sensor area yet. To study the feasibility of using PTB7 as the active layer of the micrograting vertical channel sensors, the P3HT was substituted by PTB7 for further investigations such as shelf lifetime and selectivity.…”

“…Each year, chronic kidney disease continuously robs millions of lives and consumes tremendous fortune and medical resources, − which has become a major driver of development of new medical technologies. In recent years, ultrasensitive ammonia gas sensors are widely investigated in environment or ingredient freshness monitoring. − The correlation between renal function and abnormal exhaled breath ammonia has also been corroborated. − Many kinds of ammonia gas sensors are reported by teams around the world. − ,− Technologies such as mass spectrometry, , photoacoustic laser spectroscopy, quartz crystal microbalance system, and solid-state semiconductor devices ,− have successfully demonstrated the ability to detect the concentration of the ammonia sample with high precision. However, some of these are laboratory-level instruments that have always been challenged on integrating and developing into point-of-care (POC) applications because of the unaffordable cost.…”

“…The breath figure method formed the porous structure by water droplets through evaporative cooling condensation on a solution deposited on the surface of the OSC layer. All these methods demonstrated promising results, and the sensitivity of the OSC sensor has been tremendously enhanced: the limit of detection (LOD) has lowered to 100 ppb, and some even claimed the LOD down to 10 ppb. , Moreover, some groups, including our team, have applied the OSC ammonia gas sensors to clinical trials with chronic kidney disease patients, ,− demonstrating ammonia OSC sensors with good enough air stability and long enough lifetime. , …”

The Active Components of Sunflower (Helianthus annuus L.) Calathide and the Effects on Urate Nephropathy Based on COX-2/PGE2 Signaling Pathway and the Urate Transporter URAT1, ABCG2, and GLUT9

“…The allopurinol and benzbromarone groups showed an increase in the levels of serum BUN and SCr, but a significant decline in serum UA levels. However, the HSCE group showed decreased serum UA levels with no elevation in BUN, which is involved in renal lesions ( 43 ), and the SCr levels also increased to a lesser extent in the HSCE group. These results indicate that HSCE could reduce the UA levels and prevent the development of urate renal injury.…”

Saliva as a tool for monitoring hemodialysis: a systematic review and meta-analysis

“…The references of the eight potentially eligible studies were carefully assessed, and one additional study was selected, resulting in nine studies for full-text reading. After reading the full text, the studies of Khanum et al, 4 Suzuki et al 21 and Chen et al 22 were excluded for not performing blood analysis after hemodialysis. Thus, six studies 23,24,25,26,27,28 were selected for the qualitative analysis.…”