Dan Moreau and his wife, Dianne, lived with his dire diagnosis of an incurable brain disease until a psychiatrist discovered a different explanation for his problems. (Jan Bird)

The doctor’s words were measured and unequivocal, which made her message even more devastating. Dan Moreau and his wife, Dianne, sat in stunned silence as the prominent Baltimore neurologist explained that his angry outbursts, terrifying hallucinations and faltering balance were the result of Lewy body dementia, a relentlessly progressive, largely untreatable and ultimately fatal illness that resembles both Parkinson’s disease and Alzheimer’s.

Dianne Moreau, whose first husband had died at 55 of a rapidly fatal form of kidney cancer, was dumbfounded. “I thought, ‘Can lightning be striking twice?’ ” she recalled.

For Dan Moreau, then 62 and the author of six books, several on career development and personal finance, the March 2012 diagnosis was another stark reminder of his mortality. In 2009 he had undergone successful quintuple bypass surgery to correct a heart problem. But this illness, he knew, would not end in recovery. The neurologist told him he needed to stop driving immediately. After his initial shock wore off, Dan focused on traveling with his wife of six years and spending time with family and friends.

“I wanted to appreciate things before I went nuts,” he recalled.

For more than two years, the Annapolis couple prepared for Dan’s death. He planned his memorial service and practiced skills he thought he might need as his dementia progressed. A retired reading specialist, Dianne, then 60, immersed herself in research about his disease, joined a support group and toured Maryland institutions in search of the best place for her husband when she could no longer care for him.

None of the many medical specialists they saw — a cardiologist, several neurologists, an endocrinologist, a urologist — questioned the diagnosis. But in June 2014, Dan consulted a geriatric psychiatrist for help managing his anger.

“I don’t know what you have,” Dan said the psychiatrist told him, “but it’s not dementia.”

The Moreaus were stunned and tried to tamp down their initial elation. Unraveling what was really wrong would take months of tests and a hypothesis that proved to be correct. Dan’s problems, they would discover, were easily treatable, not signs of an incurable brain disease. For both, the emotional impact of living under the specter of a fatal diagnosis has lingered. The truth, Dan said, “is still sinking in.”

Not himself

In early 2011, Dan began complaining that his “thinking wasn’t right.” He seemed unusually moody. “I had to walk on eggshells,” Dianne recalled. Recovered from his bypass surgery, he was taking a slew of drugs, including a beta blocker to reduce his blood pressure and slow his heart rate, and several to lower his cholesterol.

A CT scan of Dan’s brain found nothing unusual. But during a trip to France in June, Dan passed out while driving over a bridge. An old friend traveling with the couple grabbed the steering wheel, narrowly averting a disastrous accident. The friend later told Dianne he was shocked by how out of it Dan seemed during the trip.

For the next few months his fogginess and increasing irritability, directed mostly at Dianne, waxed and waned. Appointments with a neurologist in Annapolis failed to find anything specific. Dan complained of feeling unusually tired and said his legs felt “rubbery.”

(Robert Carter for The Washington Post)

Dianne grew increasingly alarmed. The year before her first husband died, he had reported feeling unwell, complaints that were dismissed by doctors until his diagnosis of cancer, eight weeks before his death. “I learned a very hard lesson of really researching and digging into things,” she said. She plunged into Dan’s case, but found that “none of it was making sense.”

In addition to the motor problems and anger, Dan was beset by dizziness, hallucinations and vivid nightmares. In February 2012, while Dianne was driving through a Baltimore tunnel, he became convinced it was collapsing around them. At other times he thought that his car was filled with tigers and that squirrels had invaded their bed. Sometimes he awoke in the middle of the night yelling, “What is happening?”

After tests revealed nothing, the neurologist sent him to the Baltimore specialist who diagnosed Lewy body dementia, or LBD. “She said very assuredly that Dan had a very early case,” Dianne recalled.

The disease is characterized by fluctuating but deteriorating cognitive function, vivid visual hallucinations and, in some cases, a tremor or abnormal gait. Comedian Robin Williams was diagnosed with it shortly before his suicide last year.

Dan sank into a deep depression. He viewed the cable TV series “Boss,” featuring Kelsey Grammer as a corrupt Chicago mayor coping with newly diagnosed LBD. “I watched the opening episode of that show dozens of times as Grammer’s character learns what he’s in for,” Dan recalled. “And I recommended it to my friends to help them understand the disease.”

Dianne, who had been told by the Baltimore neurologist that she might need to protect herself if Dan became violent or unmanageable, joined a support group. She grew close to two women whose husbands had LBD and learned patience, which, she said, “I needed every minute of every day.” Dan was given Aricept, the first of several dementia drugs he would take, none of which helped.

He also began passing frequent kidney stones — more than two dozen over the next two years. These hard mineral deposits are excruciating for many people; for Dan, however, they were only mildly painful. His urologist attributed them to his diet.

Getting worse

By the summer of 2012, Dan became verbally abusive, often accusing Dianne of being manipulative. “It was so unlike him,” she said. One night after Dan, in the grip of a hallucination or nightmare, pinned her to the mattress while trying to “protect” her, Dianne began sleeping in the guest room behind a locked door.

For the next year they struggledwith Dan’s condition, which was evident to close friends and relatives but not casual acquaintances. Dianne said that Dan seemed unusually aware of the impact of his behavior and remorseful about its effect on her, insight unusual for someone with dementia.

And he remained able to compensate for some deficiencies. A gourmet cook, he still prepared the couple’s meals even though it would take him four hours to make dinner and he needed to write down steps that previously had been automatic.

Dianne thought it strange that Dan was not deteriorating as fast as the husbands of women in her support group. She said that one doctor told her Dan “was so bright he was not declining at the rate a normal person would.”

In April 2014, Dan consulted a geriatric psychiatrist at Johns Hopkins for help managing his outbursts. The doctor ordered cognitive tests, and a brain scan was performed.

The results were a complete surprise. Not only did they reveal that Dan had a high level of cognitive function — inconsistent with a person who had had LBD for nearly three years — but a PET scan of his brain showed no evidence of any disease.

“I keep looking at this high calcium,” Dan remembers the psychiatrist saying. “Hasn’t anyone looked at this?”

The answer was: Not really.

It’s not clear when lab tests first revealed an elevated level of calcium in Dan’s blood, though it was noted by the neurologist who diagnosed him with dementia in 2012. Dianne said she had repeatedly asked various doctors whether Dan’s elevated calcium might be causing his symptoms but was told no. She remained skeptical; her research revealed that excess calcium, particularly in conjunction with elevated levels of parathyroid hormone, or PTH, can cause kidney stones as well as cognitive and behavioral problems.

Elevated calcium

Several doctors told her that Dan’s level of PTH, a protein produced by four tiny glands that regulate levels of calcium and phosphorous, was normal. And Dan’s calcium was only slightly elevated. A few weeks before seeing the psychiatrist, an Annapolis endocrinologist had refused Dianne’s request to order a scan of Dan’s parathyroid glands to check for a benign tumor called an adenoma, which can cause calcium and PTH levels to rise.

The psychiatrist referred Dan to Suzanne Jan De Beur, a Hopkins endocrinologist who specializes in calcium disorders.

“It was a giddy moment of disbelief,” Dan recalled. Dianne was cautious: “I felt that to protect myself, I couldn’t get too excited.”

During Dan’s initial appointment with her in October, Jan De Beur was struck by his unusual symptoms. “We don’t usually see hallucinations or angry outbursts” in patients with hypercalcemia, as elevated calcium is known, she said. And Dan’s was only 10.7 milligrams per deciliter; the upper range of normal is 10.2.

She wondered if more than one problem was causing Dan’s symptoms. First, she had to determine the reason for his elevated calcium. A scan revealed a pea-size parathyroid adenoma, which would account for the numerous kidney stones, fatigue and cognitive fuzziness.

In reviewing Dan’s long and growing list of medications, some of which he had been taking since his heart surgery, one stood out: a beta blocker called metoprolol. Jan De Beur had treated several patients who suffered from terrifying hallucinations while taking the drug; one man had tried to strangle his wife.

The problem is not new, Jan De Beur says, but remains under­recognized. As far back as 1985, doctors have reported hallucinations, vivid nightmares and behavioral disturbances in some patients who took metoprolol. Several patients, British researchers wrote, described animals in their bedrooms, just as Dan had.

At Jan De Beur’s suggestion, Dan’s cardiologist prescribed a different beta blocker. His hallucinations and nightmares disappeared. But it became increasingly clear that Dan would need surgery to remove the tumor as his levels of calcium and para­thyroid hormone rose.

In March 2015, Dan underwent a 45-minute operation. In the recovery room, he said, “it felt as though a bale of cotton had been pulled from my brain.” His mood swings and problems with thinking and motor coordination disappeared. His calcium and PTH levels quickly returned to normal, where they have remained.

Dianne’s support and persistence, he said, enabled him to get through two hellish years. Dianne credits the help provided by their internist Scott Eden.

To Jan De Beur, Dan’s experience underscores the potential pitfalls of a clinical diagnosis made largely on the basis of symptoms, not a concrete test that confirms or refutes a diagnosis. For Lewy body dementia and many other ailments, there is no such test. That’s why, she said, it’s important for doctors to ask,  ‘Is there any other explanation for this?’ “In his case you had several things coming together that looked like something else. In the meantime, he had to live with a devastating diagnosis.”

The couple has struggled to come to terms with their ordeal. Dan has met several times with a psychologist. He said he was told by another doctor that the neurologist who made the Lewy body diagnosis has been informed of her error.

Dan has not contacted her. “I don’t know what I’d say to her,” he said. “I wonder what she’d say to me.”

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