A mysterious form of kidney disease that has devastated young to middle-aged agricultural workers in Central America and South Asia appears to have surfaced in Texas.
Known as chronic kidney disease of unknown etiology (CKDu) — or Mesoamerican nephropathy — the condition continues to baffle researchers, as some otherwise healthy adults develop kidney failure without having any of the traditional risk factors.
Chronic kidney disease can range from mild to severe, potentially causing fluid buildup and increasing the risk of high blood pressure, heart disease, stroke and premature death, according to the Centers for Disease Control and Prevention.
But unlike typical cases, CKDu develops without common risk factors such as diabetes, hypertension and glomerulonephritis, a disease that inflames and damages the kidneys’ filtering units, according to Dr. Gokul Paidi, a family medicine physician at Community Healthcare Network in New York.
“It typically strikes young to middle-aged adults, more often men, who work in agriculture and manual labor in hot, low-resource regions,” he told Fox News Digital.
Several regional kidney diseases have been described over the decades, although not all are considered CKDu.
“Balkan endemic nephropathy has been documented since the 1950s; Itai itai disease in Japan was tied to cadmium-contaminated rice; and Sri Lanka nephropathy has been studied since the 1990s,” said Paidi, who has published a review on the condition.
Mesoamerican nephropathy – which was first described among sugarcane workers in El Salvador and Nicaragua in the late 1990s – is the form now being reported in the U.S., he noted.
Other locations have reported similar types of local epidemics, including Sri Lanka, India, rural Thailand and the Tierra Blanca area in Mexico, according to previous research.
“What’s emerging is that these are likely related conditions, essentially clusters of the same underlying disease process showing up in different farming and industrial regions around the world,” Paidi said.
Physicians at Houston safety-net hospitals, including Ben Taub, have treated otherwise healthy men in their 20s and 30s who presented with kidney failure — some with “Coca-Cola-colored urine,” according to Texas Monthly.
They reportedly don’t have any of the typical risk factors that cause kidney disease, like high blood pressure or diabetes.
“What’s striking about the Texas cases is how closely they mirror what we saw originally in Central America,” Paidi noted.
The patients are largely undocumented laborers from Mexico and Central America working in construction, roofing, and outdoor trades in extreme heat – jobs where water breaks are often limited, he added.
According to a review of Harris County hospital records cited by Texas Monthly, roughly one in six emergency dialysis cases in uninsured or undocumented patients had no identifiable cause, “which is consistent with CKDu,” Paidi told Fox News Digital.
Some patients are reluctant to seek care or participate in research because of their immigration status, making it harder to track the disease in Texas and detect kidney damage before it becomes irreversible, experts say.
Common symptoms of CKDu
Experts refer to CKDu as a “silent disease” because most patients don’t initially complain of any symptoms.
Most patients – especially those who work in sugarcane fields – learn they have the condition during routine screening blood tests, according to Dr. Richard J. Johnson, a leading expert on kidney diseases and emeritus professor of medicine at the University of Colorado.
“Later, it can cause typical signs of severe chronic kidney disease, including fatigue, sleep disturbances, nausea, weakness [and] shortness of breath from anemia,” he told Fox News Digital.
By the time symptoms appear and the disease is diagnosed, many patients are approaching end-stage kidney disease.
Many affected people are located in resource-poor regions where dialysis and transplants are often unaffordable or inaccessible, which can increase the odds of premature death, Paidi noted.
Potential causes
Heat stress is considered one of the leading suspected drivers of the disease, although its exact cause remains unknown, according to Johnson.
Experts believe a combination of occupational and environmental factors may gradually damage the kidneys. Strenuous outdoor labor can lead to repeated heat stress and dehydration, potentially compounded by exposure to crop pesticides and smoke from burning sugarcane.
Workers may also contend with potentially unsafe drinking water and rely on over-the-counter NSAIDs for pain — factors that, combined with repeated dehydration and heat stress, could further strain the kidneys, according to Texas Monthly.
Some experts suggest that improving hydration and shade, reducing work hours, and starting earlier in the day could reduce kidney damage.
Diagnosis and treatment
There is no specific test for CKDu. Doctors diagnose it by ruling out other causes of chronic kidney disease, along with a patient’s occupational and environmental exposures, Paidi said.
“Kidney biopsy is the closest thing to a gold standard, but isn’t practical for widespread screening,” he added.
There is no disease-specific treatment for CKDu. Management focuses on controlling blood pressure, avoiding additional kidney injury — including from NSAIDs — and using dialysis or kidney transplantation in advanced disease, according to Paidi.
Some patients receive ACE inhibitors — medications commonly used to treat high blood pressure — but these drugs can sometimes worsen kidney function in people who are dehydrated, Johnson cautioned.
“Disease often progresses rapidly over a few years, and dialysis and transplantation are rarely available, so mortality is high,” he added – which highlights the importance of screening for the condition.
For people living or working in agricultural or outdoor labor jobs, especially in hot climates, Paidi recommends getting kidney function checked with a primary care doctor at least twice a year.
“A simple blood test for creatinine (a waste product normally filtered from the blood by the kidneys) and a urine test for protein can catch early changes long before symptoms appear,” he advised.
