A Philadelphia man said he was sober, but kept testing positive for alcohol. How did a UPenn doctor crack the case?

At least once a week, every week, for years, Anthony Bing, 64, has made his way from his home in Kensington to the Philadelphia County Probation and Parole Office, where he would pee in a cup.

He is one of the hundreds of Philadelphians who, as part of their probation, have to submit to regular urine tests for drugs and alcohol. A Navy veteran, Bing has received testing since 2018 through a court program designed for veterans with addiction or mental health challenges who have been charged with crimes.

Everything seemed to be going OK until August 2023, when Bing got a call from a social worker. His urine was positive for alcohol.

Bing’s first reaction was disbelief: He says he hasn’t had a drink since Dec. 2022. His wife, Priscilla, is a former nurse, and told the social worker the test had to be wrong. “I know for a fact he wasn’t drinking,” she said.

But no one believed them.

A lot was at stake. If Bing violated the terms of his probation, they worried that he could go to jail, and lose some of the income the couple depended on from the VA and Social Security.

Desperate, they called Bing’s primary care doctor at the VA Medical Center, Aaron Schwartz, an assistant professor at the University of Pennsylvania.

Schwartz believed Bing. But he knew they would need to convince the court that Bing hadn’t violated his probation. To get proof, Schwartz performed an unconventional experiment to test an unconventional hypothesis.

The results would reveal profound flaws in the way urine is tested for alcohol — affecting not only Bing and the hundreds of other Philadelphians on probation, but anyone else (especially those with a common medical condition) who must submit urine tests to prove they are sober.

If Bing was telling the truth about not drinking, Schwartz needed to find another explanation for why there was alcohol in his urine.

Luckily, he had a theory.

When Bing came to see Schwartz at the Corporal Michael J. Crescenz Department of Veterans Affairs Medical Center on Woodland Avenue, the doctor ran the test again. This time, Bing’s urine came back negative for alcohol, as well as for a breakdown product of alcohol. If positive, this would indicate Bing had been drinking in recent days.

But Bing’s urine did contain something curious: “gram-positive organisms,” which can convert sugar to alcohol.

Schwartz then called the probation office that collects the urine tests, and asked about their procedures. They said that, unlike at the VA clinic, they sent the urine samples to an external lab once per day. So samples could sit for hours, unrefrigerated, before being tested.

Schwartz tried to replicate those conditions: He left the same urine sample that had tested negative at room temperature for 24 hours, then had it retested. It was positive.

“That was the moment when I thought ‘I think we’ve cracked this,’” Schwartz said.

When Bing first walked into Schwartz’s office in 2020, he was dealing with uncontrolled diabetes. After Schwartz learned about Bing’s problems with his urine, he found examples in the scientific literature where patients with uncontrolled diabetes — who had sugar in their urine — also had positive alcohol tests, despite being sober.

Schwartz had prescribed Bing medication that had gotten his diabetes under control, so his diabetes couldn’t be causing the problem. But what about his diabetes medication?

Bing was taking the diabetes drug Jardiance, a top-selling drug, which has been prescribed nearly 60 million times as of August 2023. Jardiance works by causing the body to flush excess sugar into the urine, so it can be excreted.

And that, Schwartz concluded, was the explanation for why Bing’s urine kept testing positive for alcohol: The Jardiance was adding sugar to his urine, and that sugar, if left at room temperature, was turning into alcohol.

The Philadelphia Courts are not convinced, noting that Bing has failed other types of tests, too. His urine tested positive for alcohol even after an “instant” test, so a delay in testing couldn’t explain the results, according to a spokesperson for the courts, which oversee the urine drug and alcohol testing for people on probation.

In response, Schwartz said Bing’s urine could produce unreliable results, even without a testing delay. Because urine can sit in the bladder for a while before being excreted, there is time for the “gram-positive organisms” to convert extra sugar to alcohol.

“I’m not surprised this is still a problem with instant testing,” Schwartz said.

Doctors call the phenomenon urinary auto-brewery syndrome, in which excess sugar in the urine (say, from diabetes) can turn into alcohol while inside the body. In a 2020 case report in the Annals of Internal Medicine, the syndrome caused a 61-year-old woman with diabetes to fail the urine alcohol tests required for a necessary liver transplant.

Urine tests for alcohol could be “misleading” — especially for people with diabetes taking Jardiance, said Kenichi Tamama, medical director of the clinical toxicology laboratory and professor of pathology at the University of Pittsburgh Medical Center, and author of the 2020 case report. “We will likely see cases similar to Bing’s case more in the future.”

At first, Schwartz felt good that he had confirmed his hypothesis about why Bing’s urine kept testing positive for alcohol, knowing that it could help keep Bing from facing repercussions. But Schwartz also realized that if this had happened to Bing, it was likely happening to others.

“This is kind of a cool, interesting, medical mystery case. But it also probably is very important to a lot of people in this country.”

Schwartz called a friend of his who could offer some insight into the implications of his findings for other people on probation: Tamar Lerer, now the forensic practice lead at the New Jersey Office of the Public Defender.

When Lerer heard about Anthony Bing, she felt a “combination of pride and horror” — pride for her friend, who stepped up to help show how Bing could be telling the truth, and horror at how many other people on probation could be having the same experience, without someone like that in their corner. “It’s truly terrifying,” she said.

So Schwartz and Lerer began trying to get the word out about the risks of misleading test results if people have diabetes or their urine isn’t tested immediately. Schwartz published a report in the highly regarded medical journal, the New England Journal of Medicine. He and Lerer wrote about Bing’s case in MedPage Today.

The probation program Bing was participating in was one of many that have launched in recent years, as courts have tried to divert nonviolent offenders from incarceration, which is expensive and often offers little hope for rehabilitation. But these programs can adopt a hard line with participants, and violations of the terms of their probation could result in prison.

In Philadelphia alone, Bing is one of nearly 500 people on probation who are required to submit to regular drug testing, including alcohol.

Many ended up before a judge with personal stories like Bing’s.

After serving in the Navy from 1981 and 1986, Bing had held a series of jobs, including working with people with disabilities. But he began using drugs.

In 2018, after pleading guilty to aggravated assault and attempted burglary (about which he declined to share details), Bing was sentenced to a short stint in prison, and five years of probation.

Legally blind and partially paralyzed, Bing attended dozens of required court check-ins, and participated in treatment classes offered by the VA’s Addiction Recovery Unit. And at least once a week, every week, for years, he went to 714 Market St. and peed in a cup.

Ever since August 2023, his urine has continued to test positive for alcohol. Schwartz has written multiple letters to the court, hoping to save Bing from violating his probation. “Please stop testing Mr. Bing’s urine for ethanol, especially several hours after collection,” Schwartz wrote in May.

The spokesperson for the Philadelphia courts said Bing hadn’t been sanctioned for the positive test results, but didn’t elaborate further.

Bing’s probation period is set to end in November — which can’t come soon enough for him and his wife, who always worries whether Bing will leave his next court hearing in handcuffs. “It’s like living on pins and needles,” said Priscilla Bing. (She sits in on interviews with her husband, who often can’t recall details or facts from his experience due to PTSD.)

The whole ordeal has been exhausting, said Priscilla Bing. “We’re basically being persecuted needlessly over a medication that is life sustaining, because he has a disease that requires him to take it,” she said.