We use cookies to understand how you use our site and to improve your experience. This includes personalizing content and advertising. To learn more, click here. By continuing to use our site, you accept our use of cookies. Cookie Policy.

Features Partner Sites Information LinkXpress
Sign In
Advertise with Us
Technopath Clinical Diagnostics

Download Mobile App


ATTENTION: Due to the COVID-19 PANDEMIC, many events are being rescheduled for a later date, converted into virtual venues, or altogether cancelled. Please check with the event organizer or website prior to planning for any forthcoming event.
22 May 2021 - 26 May 2021
Virtual Venue
25 May 2021 - 28 May 2021

Breath Ammonia Biomarker Predicts Kidney Function in CKD Patients

By LabMedica International staff writers
Posted on 18 Nov 2020
Print article
Image: The Ammonia Breath test: the sensing system included a desiccation cylinder, an airtight sensing chamber, a rotameter, a pump, and an electrical signal measurement instrument (Photo courtesy of Chang Gung University).
Image: The Ammonia Breath test: the sensing system included a desiccation cylinder, an airtight sensing chamber, a rotameter, a pump, and an electrical signal measurement instrument (Photo courtesy of Chang Gung University).
Chronic kidney disease (CKD) is a type of kidney disease in which there is gradual loss of kidney function over a period of months to years. Initially there are generally no symptoms; later, symptoms may include leg swelling, feeling tired, vomiting, loss of appetite, and confusion.

Diagnosis of CKD is largely based on history, examination and urine dipstick combined with the measurement of the serum creatinine level. It is important to differentiate CKD from acute kidney injury (AKI) because AKI can be reversible. One diagnostic clue that helps differentiate CKD from AKI is a gradual rise in serum creatinine (over several months or years) as opposed to a sudden increase in the serum creatinine (several days to weeks).

Nephrologists at the Chang Gung Kidney Research Center (Taoyan, Taiwan) and their colleagues investigated whether exhaled breath ammonia measurement could be used for rapid CKD screening. The scientists enrolled 121 patients with CKD stages 1 to 5 (average age, 61 years; 62 patients were men) and compared breath ammonia level measurements with blood urea nitrogen (BUN), creatine and eGFR levels. The gas measurement system used in this study was composed of a rotameter, pump, desiccation cylinder, the sensing chamber, and an electrical signal measurement instrument (Keysight Technologies, Santa Rosa, CA, USA).

The team reported that breath ammonia level correlated with BUN, serum creatinine, eGFR and inversed eGFR levels. Breath ammonia concentration was increasingly elevated at each stage of CKD (stage 1: 636 ± 94 ppb; stage 2: 1,020 ± 326 ppb; stage 3: 1,943 ± 326 ppb; stage 4: 4,421 ± 1,042 ppb; stage 5: 12,781 ± 1,807 ppb). The area under curve for a breath ammonia level cutoff concentration of 1,187 ppb comparing patients with eGFR of at least 60 mL/min/1.73 m2 with patients with eGFR of no more than 60 mL/min/1.73 m2 was 0.831 (positive predictive value, 0.84; negative predictive value, 0.61; sensitivity, 71%; specificity, 78%).

The scientists noted that at 886 ppb, the sensitivity increased to 80%, but the specificity decreased to 69%. They also wrote there were no significant differences between patients in each stage regarding sex, body weight, hemoglobin, albumin, comorbidities and medication and that BUN level, creatinine and eGFR increased with each CKD stage.

Ya-chung Tian, MD, an associate professor of nephrology and a co-author of the study, said, “Because CKD is non-life threating and breath ammonia detection was conducted in real time, inexpensive, easy to administer and had an acceptable diagnostic accuracy, breath ammonia can be used as a good surrogate for kidney function and a reliable tool for CKD screening.”

The authors concluded that breath ammonia detection with vertical-channel organic semiconductor (V-OSC) is a real time, inexpensive, and easy to administer measurement device for screening CKD with reliable diagnostic accuracy. The study was published on October 31, 2020 in the journal Biomedical Materials and Nanomedicine.

Related Links:
Chang Gung Kidney Research Center
Keysight Technologies

Gold Supplier
SARS-CoV-2 Antibody Test
SARS-CoV-2, Flu A/B, RSV Test
Amplidiag RESP-4
Disposable Sample Saliva Collection Kit
Disposable Sample Saliva Collection Kit
Flow Cytometer
Amnis CellStream

Print article
Mayo Medical Laboratories
BIOHIT  Healthcare OY


Molecular Diagnostics

view channel
Image: Photograph of the novel capsule-based smell test (Photo courtesy of Queen Mary University of London)

A Novel Capsule-Based Smell Test for Diagnosis of Neurological and Respiratory Diseases

To aid in diagnosing diseases where loss of the sense of smell is a symptom, such as in chronic neurological conditions like Parkinson's and Alzheimer's diseases and in acute respiratory infections such... Read more


view channel
Image: The Hamamatsu Photonics Nanozoomer 1 Digital Slide Scanner (Photo courtesy of University of Adelaide)

Genetic Background and Clinicopathologic Features Established for Adult-Onset Nephronophthisis

Nephronophthisis (NPH) is a genetic disorder of the kidneys which mainly affects children. It is classified as a medullary cystic kidney disease. The disorder is inherited in an autosomal recessive fashion... Read more


view channel
Image: DxA 5000 Fit (Photo courtesy of Beckman Coulter)

Beckman Coulter Becomes First Diagnostics Company to Offer Workflow Automation Specifically for Mid-Volume Laboratories

Beckman Coulter (Brea, CA, USA) has announced the global launch of the DxA 5000 Fit, a workflow-automation solution designed to fit into medium-sized labs that run fewer than 5,000 tests a day.... Read more
Copyright © 2000-2021 Globetech Media. All rights reserved.