Several patients at a South Dakota urology clinic have filed a federal class-action lawsuit against it, charging sloppy practices may have exposed them to disease.

A routine health department inspection at the Siouxland Urology Center in Dakota Dunes found potential hazards during cystoscopies. “Single-use products, such as saline solution bags and tubing, were used on more than one patient before being discarded,” the department announced.

“The practice was immediately halted and corrective measures were implemented.”

The practice sent letters to 5,200 patients who had undergone the procedure since 2002, warning that they may have been exposed to blood-borne infections, including hepatitis B, hepatitis C and HIV, although the risks were small. Within days, five patients had filed the lawsuit.

In addition to malpractice and negligence, the plaintiffs are charging battery and unjust enrichment among other claims. They seek more than $5 million in damages, including compensation for repeated tests, treatment, and associated costs, the Associated Press reports.