Breaking News
February 23, 2019 - Surprise rheumatoid arthritis discovery points to new treatment for joint inflammation
February 23, 2019 - A just-right fix for a tiny heart
February 23, 2019 - Owlstone Medical and Shanghai Renji Hospital collaborate to initiate breath biopsy lung cancer trial
February 23, 2019 - AMSBIO’s comprehensive portfolio of knock-out cell lines and lysates
February 23, 2019 - New app reliably determines physicians’ skills in forming accurate, efficient diagnoses
February 23, 2019 - Peripheral nerve injury can trigger the onset and spread of ALS, shows study
February 23, 2019 - Researchers uncover mechanisms that prevent tooth replacement in mice
February 23, 2019 - Once-a-day capsule offers new way to reduce symptoms of chronic breathlessness
February 23, 2019 - FDA Adds Boxed Warning for Increased Risk of Death with Gout Medicine Uloric (febuxostat)
February 23, 2019 - Phone-based intervention aids rheumatoid arthritis care
February 23, 2019 - Opioid epidemic makes eastern inroads and targets African-Americans
February 23, 2019 - New identified biomarker predicts patients who might benefit from HER2-targeted agents
February 23, 2019 - Study offers new insights into mechanisms of changes in erythrocytes under stress
February 23, 2019 - Antipsychotic polypharmacy may be beneficial for schizophrenia patients
February 23, 2019 - Researchers investigate how marijuana and tobacco co-use affects quit attempts by smokers
February 23, 2019 - Patients with diabetes mellitus have high risk of stable ischemic heart disease
February 23, 2019 - Transparency on healthcare prices played key role in Arizona health system’s turnaround
February 23, 2019 - A comprehensive, multinational review of peppers around the world
February 23, 2019 - Study finds modest decrease in burnout among physicians
February 23, 2019 - A simple change can drastically reduce unnecessary tests for urinary tract infections
February 23, 2019 - Deep Learning-Enhanced Device Detects Diabetic Retinopathy
February 23, 2019 - Researchers discover new binding partner for amyloid precursor protein
February 23, 2019 - Modest decrease seen in burnout among physicians, researchers say | News Center
February 23, 2019 - Transplanting bone marrow of young mice into old mice prevents cognitive decline
February 23, 2019 - Mogrify to accelerate novel IP and cell therapies using $3.7m USD funding
February 23, 2019 - Johns Hopkins study describes cells that may help speed bone repair
February 23, 2019 - Scientists demonstrate influence of food odors on proteostasis
February 23, 2019 - Researchers unlock the secret behind reproduction of fish called ‘Mary’
February 23, 2019 - Acupuncture Could Help Ease Menopausal Symptoms
February 23, 2019 - Researchers use AI to detect early signs of Alzheimer’s
February 23, 2019 - On recovery, vulnerability and ritual: An exhibit in white | News Center
February 23, 2019 - Memory Stored in Unexpected Region of the Brain
February 23, 2019 - Several health experts worldwide gather at EUDONORGAN event
February 23, 2019 - Discovery of potent compound in native California shrub may lead to treatment for Alzheimer’s
February 22, 2019 - Researchers create new map of the brain’s own immune system
February 22, 2019 - ICHE’s reviews on surgical infections, unnecessary urine tests, and nurses’ role in antibiotic stewardship
February 22, 2019 - UK Research and Innovation invests £200 million to create new generation of AI leaders
February 22, 2019 - Takeda collaboration to boost fight against Alzheimer’s and other neurodegenerative diseases
February 22, 2019 - Heavy drinking may change DNA, leading to increased craving for alcohol
February 22, 2019 - U.S. opioid deaths jump fourfold in 20 years; epidemic shifts to Eastern states | News Center
February 22, 2019 - 5 Questions with William Turner on Diversity in Medicine
February 22, 2019 - HHS Finalizes Rule Seeking To Expel Planned Parenthood From Family Planning Program
February 22, 2019 - Researchers uncover biochemical pathway that may help identify drugs to treat Alzheimer’s
February 22, 2019 - Biologist uses new grant to find ways to eliminate schistosomiasis
February 22, 2019 - Bag-mask ventilation to help patients breathe during intubation prevents complications
February 22, 2019 - AbbVie Announces New Drug Application Accepted for Priority Review by FDA for Upadacitinib for Treatment of Moderate to Severe Rheumatoid Arthritis
February 22, 2019 - Nature versus nurture and addiction
February 22, 2019 - New website connects researchers with data experts, resources | News Center
February 22, 2019 - Today’s Concerns About Drug Prices Echo The Past
February 22, 2019 - CT and Doppler equipment have low accuracy in detecting cerebral vasospasm and ischemia
February 22, 2019 - Study finds out similarity in function between healthy retina cell and tumor cell
February 22, 2019 - CWRU awarded NIH grant to identify effective treatments for intimate partner violence
February 22, 2019 - Oncotype DX Not Cost-Effective for Low-Risk Breast Cancer
February 22, 2019 - Scientists discover new type of immune cells that are essential for forming heart valves
February 22, 2019 - Talk About Déjà Vu: Senators Set To Re-Enact Drug Price Hearing Of 60 Years Ago
February 22, 2019 - Genetic defect linked to pediatric liver disease identified
February 22, 2019 - New cellular atlas could provide a deeper insight into blinding diseases
February 22, 2019 - Growing number of cancer survivors, fewer providers point to challenge in meeting care needs
February 22, 2019 - Innovative compound offers a new therapeutic approach to treat multiple sclerosis
February 22, 2019 - $1.5 million grant to develop opioid treatment program for jail detainees
February 22, 2019 - FDA’s new proposed rule would update regulatory requirements for sunscreen products in the U.S
February 22, 2019 - Most Hip, Knee Replacements Last Decades, Study Finds
February 22, 2019 - Wellness problems prevalent among ob-gyn residents
February 22, 2019 - In the Spotlight: “The world is your oyster in geriatrics”
February 22, 2019 - Successful testing of multi-organ “human-on-a-chip” could replace animals as test subjects
February 22, 2019 - Analysis of cervical precancer shows decline in two strains of HPV
February 22, 2019 - Sugary stent eases suturing of blood vessels
February 22, 2019 - From surgery to psychiatry: A medical student reevaluates his motivations
February 22, 2019 - Is New App From Feds Your Answer To Navigating Medicare Coverage? Yes And No
February 22, 2019 - New pacemakers powered by heartbeats could reduce need for surgery
February 22, 2019 - The United States records highest drug overdose death rates
February 22, 2019 - Heart attacks more likely to be fatal in women and rates are rising
February 22, 2019 - Morning walks could be better than drugs at lowering blood pressure
February 22, 2019 - Phase 1 data reinforce safety profile of new drug for treating Duchenne muscular dystrophy
February 22, 2019 - Vitamin D supplementation less effective in the presence of obesity, shows study
February 22, 2019 - Novostia raises CHF 6.5 million to advance its aortic, mitral heart valve to clinical trials
February 22, 2019 - CPRIT awards nearly $20 million to The University of Texas MD Anderson Cancer Center
February 22, 2019 - Sarepta Announces FDA Acceptance of Golodirsen (SRP-4053) New Drug Application for Patients with Duchenne Muscular Dystrophy Amenable to Skipping Exon 53
February 22, 2019 - An institutional effort to reduce the amount of opioids prescribed following lumbar surgery
February 22, 2019 - Family-history-based models perform better than non-family-history based models
New study suggests testing urine and blood serum as better way to diagnose myeloma

New study suggests testing urine and blood serum as better way to diagnose myeloma

image_pdfDownload PDFimage_print

When it comes to diagnosing a condition in which the plasma cells that normally make antibodies to protect us instead become cancerous, it may be better to look at the urine as well as the serum of our blood for answers, pathologists say.

The condition is monoclonal gammopathy, in which immune cells called plasma cells start making just one immunoglobulin, or antibody, instead of their usual vast array. The result can be the cancer multiple myeloma.

“When you test the serum, we suggest you also test the urine whenever you suspect that somebody has a tumor of the plasma cells,” says Dr. Gurmukh Singh, vice chair of clinical affairs for the Department of Pathology at the Medical College of Georgia at Augusta University.

The decades-old urine test is still used by pathologists and requested by physicians, but its use declined when the serum free light chain assay became available about a dozen years ago, Singh says, and some physicians may now think that the urine test is redundant. The different tests look in the serum or urine for signs of the abnormal antibody, and to see if the usual ratio is off for two types of a portion of the antibody, called light chains.

The new study, published in the Journal of Clinical Medicine Research, indicates that if the multiple myeloma is associated with the type called the lambda light chain, there is about a 25 percent chance the problem will not be detected by the serum test for free light chains, the investigators report from their retrospective review of tests on 175 patients.

“If you have a lambda chain-associated lesion and you don’t do a urine study, just rely on the serum free light chain assay, about 1 out of 4 times, the assay will tell you that you don’t have anything when you actually do,” says Dr. Won Sok Lee, fourth-year pathology resident at MCG and AU Health and the study’s coauthor.

Plasma cells are immune cells that live in our bone marrow and produce immunoglobulins, antibodies that attach to and attack invaders. When the plasma cells go bad, they instead start producing a single, dysfunctional immunoglobulin.

The Y-shaped immunoglobulins are comprised of pieces of protein called “heavy” and “light” chains and, as the name implies, the light chains are literally lighter. Light chains have two different types, kappa and lambda, which are distinctive in their amino acid sequence. We normally make about twice as many kappa light chains, but cancer can affect both light chains.

In multiple myeloma, the relevant light chain production goes up but kappa goes up a lot more, says Singh, the study’s corresponding author and Walter L. Shepheard Chair in Clinical Pathology at MCG.

Sometimes their ratio stays normal even when an abnormal lambda immunoglobulin is showing up in the urine.

Conversely, nearly 40 percent of patients have an abnormal ratio without having monoclonal gammopathy, the investigators write.

These variabilities mean some patients, particularly those with the less-common lambda chain-associated lesions, could go undiagnosed, Lee says.

“You may go undiagnosed because the serum free light chain test either is not picking up those abnormal proteins or the lambda lesions don’t make that many excess abnormal proteins,” Singh notes.

Underdetection of the lambda light chains floating in the serum may account for the false negative ratio found in about 25 percent of patients who clearly had an abnormal antibody produced by a lambda lesion present in their urine, the investigators report.

Underproduction of lambda free light chains in these patients likely accounts for another 5 percent of false negatives, they write.

In fact, the kappa/lambda ratio showed excess kappa chains in about 90 percent of the patients who had an abnormal ratio without a tumor of the plasma cells, the investigators say.

With lambda chain-associated lesions, the ratio is not abnormal nearly as frequently. In fact, there is a high false negative rate for a lambda-dominant ratio in monoclonal gammopathies associated with lambda chains, they write, possibly due to the under-detection of lambda light chains in the serum.

Therein lies the problem with not looking for errant antibodies and light chain ratios in the urine, Lee says. Ratios can look normal in the serum, while the urine has monoclonal lambda chains.

“If it’s in the urine, you are making abnormal free light chains,” Lee says. Conversely, the ratio can look abnormal in the serum in people who don’t have cancer.

Although more costly, the urine test is a better diagnostic tool in this case, because it enables the pathologist to give better information back to physicians and patients, Lee says. He notes that kappa lesions are more common.

The investigators found a systematic underdetection of serum free lambda light chains by the serum free light chain assay and an underdetection as well of the lambda dominant ratio.

Examination of serum free light chains is currently recommended for diagnosing and monitoring monoclonal gammopathies, although, the investigators write, there are differing opinions on its usefulness. If initial tests indicate a problem, a bone marrow biopsy is typically performed to confirm a diagnosis.

Excessive light chains produced normally are easily excreted in the urine because of their small size. With monoclonal gammopathy, some of the excess light chains can get trapped in the kidneys and damage kidney function.

They examined test results on 175 patients who had serum protein electrophoresis/serum protein immunofixation electrophoresis; urine protein electrophoresis/urine protein immunofixation electrophoresis; and serum free light chain assay from 2010-16.

Early symptoms of monoclonal gammopathy can be nonspecific, like feeling poorly, and if it becomes cancer, one of the first symptoms may be a fractured bone because the cancerous cells have started consuming bone, Singh says. Anemia, an increase in serum calcium and kidney failure are other symptoms.

Tagged with:

About author

Related Articles