18 Months Later

Andrew Karnes and his family

A cytochrome P450 test showed that Andrew Karnes poorly metabolized his psychiatric medications — a finding that led to his recovery.

Written by Susan McKeague Karnes

An individualized medicine test developed by Mayo Clinic gives a mother her son back

When my parents became Major Benefactors of Mayo Clinic, they did so selflessly. They aimed to help others, to support research, to fund efficacious medicine — and to save lives. I am certain that my father, who died a few weeks before my son Andrew went to Mayo, never dreamed that the generosity of Mayo benefactors, and a test developed by Mayo's scientists, would save one very precious life.

On a brilliant autumn afternoon last October, my son sent a text message, a 17-second video taken atop a mountain that he had just climbed with his dad.

As the camera panned, I glimpsed my smiling husband and Idaho's stunning Sawtooth Mountains. The final frames remain forever etched on my heart: My son Andrew's steady hand emerged in the foreground and formed a "thumbs up."

Ordinary moments like that one, a happy father-and-son hike in the wilderness, may be mundane for most families, but for ours it was nothing short of a miracle. A miracle created by Mayo Clinic.

Eighteen months ago, Andrew was a psychiatric patient in the death grip of suicidal depression, the frightening nadir of a 16-year struggle that began with a simple strep infection.

Our youngest child was a fairly typical 10-year-old Texan — happy and energetic. But then during the second week on a regimen of antibiotics, cough suppressants and decongestants, Andrew exhibited a puzzling set of behaviors consistent with obsessive-compulsive disorder (OCD).

Within a year, his hands developed a mild tremor. A medication was prescribed. In junior high, he was diagnosed with anxiety; medications were adjusted. Two years later, he was diagnosed with depression. At 17, he began to battle poor sleep and fatigue.

For 16 years, medications were added, adjusted, changed. Andrew grew quieter and lost his characteristic optimism. My husband and I consulted with his specialists and expressed concern. Physicians cited studies and family members with benign tremor or mild anxiety and convinced us to continue the course of treatment. I was admonished to accept my son's psychiatric diagnoses rather than question them.

In 2011, Andrew's condition deteriorated. His OCD, anxiety and depression grew severe — all exacerbated by profound fatigue and the tremor in his hands, now too debilitating for him to easily eat or use a cellphone. Traditional treatments were failing.

When hospital lab tests indicated abnormal thyroid function, Andrew's psychiatrist recommended we take him to Mayo Clinic. In fact, I had already begun arrangements. My parents had been benefactors and patients for years. Given Andrew's baffling array of symptoms, we urgently needed Mayo's interdisciplinary approach and exemplary level of care.

In early July, we traveled from our home in Texas and met Andrew's primary physician at Mayo, internist Kevin C. Fleming, M.D. My journal noted, "He is extremely thorough and seems to take us very seriously." I wrote those words as a sigh of relief as I felt the first delicate sprig of hope.

Dr. Fleming and his colleagues proved thorough indeed. Within weeks, they eliminated numerous conditions. Yet EEG, MRI and EMG results seemed to propel us toward serious treatments — deep brain stimulation for the tremor and electroconvulsive therapy for the OCD. Before implementing the therapies, we visited psychiatrist Shirlene Sampson, M.D., for another consultation.

A consultation changes everything

Listening to my concern about Andrew's numerous medications and noting my husband's sensitivity to certain drugs, Dr. Sampson suggested Andrew undergo a cytochrome P450 test that Mayo scientists developed. The results measured Andrew's ability to metabolize medications.

Days later, a smiling Dr. Sampson greeted us. Test results proved that Andrew poorly metabolized medications through two enzymes, 2D6 and 2C19, common pathways for many drugs — in Andrew's case, for the exact ones he took.

Intermediate metabolizers like Andrew do not process medications at the same rate as normal metabolizers. His symptoms, Dr. Sampson explained, were likely the result of toxicity. In other words, he had too much medicine built up in his system.

In mid-August, we returned home and, under medical supervision, began the slow and difficult process of weaning Andrew from his medications. Because of his metabolism profile, we reduced drugs in small increments over many days and weeks — at less than half the rate of a normal metabolizer.

Within a month, Andrew's OCD dissipated. His psychiatrist in Texas said he no longer met the clinical criteria for the diagnosis. A month later, his doctor scratched the diagnosis of depression.

Andrew also has learned new skills — including how to avoid moderate anxiety through tapping and using a light to help regulate his sleep cycle. My husband and I marveled at the change in our son. His mood and tremor improved on a daily basis.

Today, life is redefined. In early 2012, my husband and I moved to Idaho. Andrew opted to move, too, and start life over with his clean bill of health.

Eighteen months ago, Andrew was on medical leave. Today, he enjoys a job with a national company and volunteers at Zoo Boise. Eighteen months ago, Andrew napped frequently throughout the day, awoke 38 times an hour and never felt rested. Today, he sleeps well, wakes refreshed, and enjoys hiking and mountain biking. Eighteen months ago, our youngest son did not want to live. Today, Andrew truly lives a rich, happy and fulfilling life.

Talk about a "thumbs up." The vista for Andrew is limitless, as is our gratitude for Mayo Clinic's benefactors, scientists and physicians.