Ian Liu’s back was killing him — and no matter what he tried, it wasn’t getting better.

The 39-year-old Coast Guard officer assumed he had wrenched his back caring for his infant son, not surprising given his long history of lower back problems. But this time, the pain was much more intense and persistent, and neither physical therapy nor painkillers seemed to help.

For more than a month, Liu shuttled between two Washington area military hospitals, searching for an explanation and, especially, relief.

“It was the worst pain I’d ever had,” Liu recalled. A series of tests failed to explain his deteriorating condition, which stumped the medical personnel who treated him.

It was only after Liu’s wife confided that he sometimes seemed disoriented that a doctor looked beyond the obvious problem and discovered the source of Liu’s pain. The cause turned out to be unrelated to his orthopedic history — and far more serious than a bad back.

Collapse in the commissary

Liu first noticed the pain on a Friday night, Dec. 3, 2004, after he finished bathing the youngest of his three sons.

“I assumed it was just from bending over the tub,” recalled Liu, who figured it would improve with time, as such problems had in the past. But the next day, his pain was worse, and as he wheeled his shopping cart around a Northern Virginia commissary, Liu was glad he had something to lean on.

At the food court where his family stopped for lunch, Liu said, he suddenly felt faint. Paramedics were summoned, and he was taken by ambulance to an emergency room where he had a CT scan of his back along with X-rays and blood tests. After nothing was found, he was sent home with a painkiller, muscle relaxer and instructions to call his primary-care doctor in a few days if he didn’t feel better.

He didn’t. The drugs made him groggy but didn’t seem to touch the pain or blunt the periodic muscle spasms in his back.

On Dec. 7, he saw a physician assistant in the primary-care clinic at a local military hospital. The PA gave Liu a five-day course of corticosteroids to reduce inflammation, along with a more potent muscle relaxer and a painkiller. He advised Liu to see the chiropractor who had previously treated him for back pain.

The next day, the chiropractor tried to manipulate Liu’s spine but soon stopped when it was clear that Liu was in too much pain. He recommended that Liu get an MRI scan, which was performed a few days later, and make an appointment with a neurosurgeon.

“I thought maybe I had a herniated disk or something,” Liu recalled, of the condition that occurs when a disk in the spine slips out of position.

A week later, still miserable, Liu returned to the clinic. The PA referred him to a physical therapist. But at his first session two days later, Liu was unable to tolerate any exercises. By this time, he had lost nearly 10 pounds off his already-thin frame.

“Sitting and standing were the worst,” Liu recalled. “Lying down, at least I didn’t have pressure on my back.” He had made an appointment with a neurosurgeon, but the first opening was three weeks away.

Liu had a more immediate concern. He, his wife and sons had reservations to fly to San Francisco to see his extended family, and Liu wasn’t sure how he would be able to manage the long-anticipated trip. He was in so much pain that he could barely walk.

He loaded up on prednisone, a corticosteroid, and painkillers; using a wheelchair to board the plane, he made the cross-country trip. “I was really out of it the whole time,” he recalled of his days in California. The painkillers made him “dopey and tired,” and he noticed that he sometimes had double vision or felt winded, which he assumed were side effects of the drugs.

His parents, he said, were alarmed by his condition and kept urging him to go to a hospital emergency room.

“I deflected,” he recalled. “I thought, ‘Why sit in an ER for hours and have them tell me I need to see a neurosurgeon when I already have an appointment?’ ”

Liu said his wife, Julie, was “fed up with me” and exhausted caring for three boys younger than 7 and a husband who was increasingly out of it. Liu said he told himself that everything would be sorted out when he saw the surgeon, even if it meant back surgery.

‘Just man up’

The Jan. 4, 2005, appointment with the neurosurgeon started on a sour note. Liu’s MRI had been performed without contrast dye, so the surgeon ordered a new one that would provide more information. But after viewing the results of the new scan, the specialist had disheartening news.

“He told me, ‘I don’t know what’s going on, but I see nothing surgical to fix,’ ” recalled Liu, adding that this was the lowest moment of his ordeal — even worse than what would come later. “I felt like maybe this is just in my head and it’s not really that bad. Why couldn’t I just man up and take it?”

But Liu’s wife had grown increasingly alarmed; while her husband was out of the room, she told the neurosurgeon that he was showing signs of confusion and disorientation and seemed short of breath.

That evening, after the couple had returned to their Springfield home, the phone rang. It was the neurosurgeon, who told Liu that his labored breathing and confusion might mean that something was wrong with his heart. Liu needed to come to the hospital right away for further testing.

“If you want, I’ll send an ambulance,” Liu recalls him saying. Liu opted to have his wife drive him.

At the hospital, the medical technician checking his vital signs asked him, “Do you know you’ve got a [heart] murmur?”

“I didn’t even know what that was,” Liu recalled, “but they seemed very concerned.”

That concern deepened when an echocardiogram, a test that provides a detailed picture of the heart, revealed the reason for Liu’s unremitting pain, shortness of breath and confusion: He was suffering from infectious endocarditis, a bacterial infection that had eaten a hole in Liu’s mitral valve. Testing showed that the infection had spread to his brain, lungs and spine.

Endocarditis is an inflammation of the interior lining of the heart or the heart valves. Usually caused by a bacterial or fungal infection, the illness typically occurs in people with underlying cardiac problems, such as a defect in a heart valve. It can occur when bacteria are introduced into the bloodstream during medical or dental procedures, according to Medline.

These bacteria can migrate to other parts of the body, as they did in Liu’s case, causing serious infections. Tests revealed that Liu also had cerebritis, a brain infection responsible for his worsening confusion, as well as osteomyelitis and diskitis, which were the reasons for his back pain.

Liu’s infection was caused by Streptococcus viridans, bacteria found in the mouth that are a common cause of endocarditis. Liu said that he had not undergone any medical procedures, but he had had his teeth cleaned several weeks before the back pain developed; doctors have told him there is no way to know whether that precipitated his infection. And although he said he had never been told he had a heart murmur or other defect, such a condition may have predisposed him to endocarditis, said infectious-disease specialist Marc Siegel, an assistant professor at George Washington University School of Medicine.

“Back pain is a known presentation of endocarditis,” said Siegel, who has not treated Liu. “The lower back happens to be where the blood supply is most concentrated.” In a patient with a defective heart valve, the strep bacteria can flourish.

So why wasn’t Liu’s heart problem detected earlier?

The reasons for that are unclear, Siegel said. It’s impossible to know whether the murmur was new or had been present for some time but never detected. “A new murmur would be a pretty concerning finding,” he said, while a preexisting one might have alerted doctors to focus on Liu’s heart much sooner. “Unfortunately, younger doctors — and I include myself in this — are probably not as good on physical exam as [doctors] used to be.”

Many heart murmurs, which are detected by listening to the heart through a stethoscope, do not cause problems, while others found in adulthood may be a sign of valve disease.

Liu said that the specialists treating him initially expected he would receive 10 weeks of intravenous antibiotics, then undergo open-heart surgery to repair or replace his damaged mitral valve. But after a few days in the hospital, it became clear that his heart was failing and surgery could not wait. On Jan. 18, he received a new mitral valve made of bovine tissue.

For the next two years, Liu said, he took antibiotics to eradicate the infection in his back.

Now 47, Liu has retired from the military and works as an IT specialist for the State Department. Although his replacement valve has functioned well, it has worn out faster than doctors expected, and he is facing surgery this spring to replace it.

Liu said his illness has made him appreciate the importance of having an advocate to ask questions and push for care when a patient is too ill to do it.

“I was in such pain and on heavy painkillers, and I just wanted the pain to stop,” he said of the weeks preceding his diagnosis. He said he is especially grateful to the military doctor who helped coordinate his care once he learned he had endocarditis and to his wife for telling the neurosurgeon about his confusion.

“At the time, I thought I had done everything I could do.”

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