Sarcoidosis is difficult to diagnose for a variety of reasons, Mary McGowan, CEO of the Foundation for Sarcoidosis Research, told Diagnostics World. For one, it is not limited to a single area or part of the body. “It’s a rare inflammatory disease that can impact literally any organ,” she said.
Although the vast majority of people living with sarcoidosis have it in their lungs, it can also appear in the eyes, the skin, brain, heart, spinal cord, liver, kidney, and even in the bones. “So it’s challenging from that perspective, because it impacts so many different organs,” she added.
The disease causes the immune system to form clusters of cells known as granulomas. And while it resolves on its own for some, sarcoidosis can be a lifelong condition for others. In serious cases, it can lead to issues like fibrosis, blindness, or heart failure. And for the time being, the exact underlying cause of this disease remains unknown.
Sarcoidosis is a heterogeneous disease that is often referred to as a “snowflake disease” because no two patients have the same symptoms or disease progression, McGowan pointed out, “so that’s another challenge.” Furthermore, it is known to be “a great mimicker” because it can resemble plenty of other health issues, such as tuberculosis, lupus, lung cancer, or multiple sclerosis. “So there’s a lot of misdiagnoses.”
It is often treated as a disease of exclusion, she added, meaning a number of other conditions typically need to be ruled out before someone is diagnosed with sarcoidosis. Despite these sorts of difficulties, researchers—and the funders supporting their work—are continuing to make progress toward improved diagnostic and treatment options.
Blood Test Aims to Speed Along Diagnostic Process
When it comes to recent developments in this space, McGowan said one of the most talked about efforts comes from Lobelia Samavati at Wayne State University, who is a previous recipient of a research grant from the Foundation for Sarcoidosis Research.
She and colleagues developed a new project supported by the National Institutes of Health (NIH) that has led to the development of a tool meant to quickly and inexpensively diagnose sarcoidosis. The underlying idea is that a simple blood test could help reduce the use of more invasive tests that are relied upon to identify this disease.
“Dr. Samavati believes that they may have developed a blood test that would be able to show immunoglobulin antigens that could indicate sarcoidosis,” McGowan said. The research group “may have identified two newly-described disease specific antigen biomarkers that only bind to the antibodies of sarcoidosis positive patients.”
The current process of diagnosing sarcoidosis involves the removal of tissue and testing with additional screenings that are meant to rule out other potential diseases, according to James Kiley, director of NIH’s Division of Lung Diseases at the National Heart, Lung, and Blood Institute. “Using a blood test will help diagnose faster, particularly in those organs that are more challenging to biopsy and with less harm to the patient,” he said.
Paul Nicolaus is a freelance writer specializing in science, nature, and health. Learn more at www.nicolauswriting.com.