A mysterious kidney disease previously reported among agricultural workers in Central America and South Asia appears to have surfaced in Texas. The condition can drive otherwise healthy adults into kidney failure despite the absence of traditional risk factors.

Known as chronic kidney disease of unknown etiology, or CKDu, the illness is also called Mesoamerican nephropathy. Researchers remain uncertain about its precise cause as cases emerge among young adults and people in middle age.

Typical chronic kidney disease can be associated with diabetes, hypertension and glomerulonephritis, which inflames and damages the filtering units of the kidneys. CKDu develops without those common risk factors, according to Dr. Gokul Paidi, a family medicine physician at Community Healthcare Network in New York.

The condition more often strikes men who perform agricultural or manual labor in hot regions with limited resources, Paidi told Fox News Digital. He has published a review of the disease and its appearance in farming and industrial areas around the world.

Several regional kidney diseases have been documented over decades, although not all are considered CKDu. Paidi cited Balkan endemic nephropathy, Itai itai disease in Japan and Sri Lanka nephropathy among the conditions that researchers have investigated.

Mesoamerican nephropathy was first described among sugarcane workers in El Salvador and Nicaragua during the late 1990s, according to Paidi. Similar local epidemics have been reported in Sri Lanka, India, rural Thailand and the Tierra Blanca area of Mexico.

Paidi said the clusters may represent related conditions involving the same underlying disease process in different regions. “Disease often progresses rapidly over a few years, and dialysis and transplantation are rarely available.”

Physicians at Houston safety net hospitals, including Ben Taub, have treated otherwise healthy men in their 20s and 30s who arrived with kidney failure, according to Texas Monthly. Some patients had “Coca-Cola-colored urine” but lacked typical kidney disease risk factors.

“What’s striking about the Texas cases is how closely they mirror what we saw originally in Central America,” Paidi said. The patients are largely undocumented laborers from Mexico and Central America who work in construction, roofing and other outdoor trades in extreme heat, he added.

A review of Harris County hospital records cited by Texas Monthly found that roughly one in six emergency dialysis cases among uninsured or undocumented patients had no identifiable cause. Paidi said that finding was consistent with CKDu.

Tracking the disease can be difficult because some patients are reluctant to seek medical treatment or participate in research due to their immigration status. That can also hinder efforts to identify kidney damage before it becomes irreversible.

Experts describe CKDu as a silent disease because patients often report no symptoms during its early stages. Dr. Richard J. Johnson, a leading expert on kidney diseases and emeritus professor of medicine at the University of Colorado, said many workers learn they have it through routine screening blood tests.

Later symptoms can include fatigue, sleep disturbances, nausea, weakness and shortness of breath caused by anemia, Johnson told Fox News Digital. By the time those warning signs emerge and the disease is diagnosed, many patients are approaching advanced kidney disease.

Heat stress is considered a leading suspected driver, although the exact cause remains unknown. Experts believe repeated dehydration from strenuous outdoor labor may combine with pesticide exposure, smoke from burning sugarcane, potentially unsafe drinking water and NSAID use to strain the kidneys.

There is no specific test for CKDu, so doctors diagnose it by excluding other causes and examining a patient’s occupational and environmental exposures. Paidi said a kidney biopsy is the closest option to a gold standard, but it is not practical for widespread screening.

No treatment specifically targets CKDu. Care focuses on managing blood pressure, preventing additional kidney injury and providing dialysis or kidney transplantation in advanced cases, while Johnson cautioned that ACE inhibitors can sometimes worsen kidney function in dehydrated patients.

Experts have suggested providing better access to hydration and shade, reducing work hours and beginning labor earlier in the day. Paidi recommends that agricultural and outdoor workers in hot climates have their kidney function checked by a primary care doctor at least twice each 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,” Paidi advised. Early screening is especially important because symptoms may not emerge until serious kidney damage has occurred.