Difficulty identifying Alzheimer's makes misdiagnosis easy

by Todd Ackerman for The Houston Chronicle:Some treatable brain ailments are misdiagnosed as Alzheimer's, simply because they mimic many of the disease's degenerative symptoms.When Ron Shillcutt began having difficulty walking and remembering things, a simple, scary explanation came to his wife's mind: Alzheimer's disease. The doctors suspected Alzheimer's as well, or Parkinson's, but the drugs they prescribed did nothing to slow the progression of Shillcutt's symptoms, soon also including inattention, disorientation and incontinence. So Doris Shillcutt took to the Internet.There, Doris found what doctors eventually confirmed was the problem: a buildup of fluid in the brain called normal pressure hydrocephalus (NPH). A shunt was surgically implanted to drain the fluid and most of Ron's symptoms began to go away. "I got my life back," says Shillcutt.NPH is one of a number of conditions that can mimic Alzheimer's, the degenerative brain-robbing disease that afflicts some 5.4 million Americans and is projected to explode in the coming decades as the population ages. Estimates call for the numbers to grow to 6.7 million by 2025 and to anywhere from 11 million to 16 million by 2050, barring the development of a breakthrough to prevent or stop the disease.More than half of the 5.4 million are undiagnosed, a testament to seniors' slowness to seek treatment and the difficulty diagnosing the disease, which traditionally could only be definitively done by autopsy. The difficulty is most prevalent among primary-care doctors, who sometimes dismiss early-stage symptoms as age-related forgetfulness.But the difficulty identifying Alzheimer's also makes misdiagnosis easy, mostly for other degenerative brain diseases with similarly devastating prognoses, but occasionally for readily treatable conditions. Such treatable misdiagnoses number in the tens of thousands, say experts."They can be quite common, really," says Dr. Paul Schulz, a neurologist and director of the University of Texas Medical School at Houston's Memory Disorders and Dementia Clinic. "There are so many things that can account for brain problems, it's no wonder doctors get fooled."All told, there are dozens of conditions whose symptoms can resemble those of Alzheimer's. The most common include depression, thyroid disease, urinary-tract infections, vitamin B12 deficiencies, the herpes simplex virus, heavy drinking and sleep apnea. CPAP breathing machines make the last particularly easy to treat.Neurologists also report that cognitive symptoms can resolve themselves when certain medications or combinations of medications are stopped. Those include many antihistamines, anti-anxiety drugs, sleeping pills and muscle relaxants that block a brain chemical, acetylcholine, many Alzheimer's medications boost. The chemical sends signals in the nervous system.But the most common culprit may be NPH, according to a study in the journal Neurosurgical Focus in 2007. The study of 147 nursing-home residents estimated that 9 percent to 14 percent met the criteria for NPH.The condition involves brain-cushioning cerebrospinal fluid that is normally absorbed and replenished but that accumulates in sufferers and causes pressure that leads to the sort of memory loss, shuffling gait and incontinence that Shillcutt experienced.Dr. Dong KIm, a neurosurgeon and director of Memorial Hermann Hospital's Mischer Neuroscience Institute, says that for those patients for whom the walking problems are more advanced than the mental ones, the surgical implantation of a shunt that drains the excess fluid from the brain to the abdomen will correct at least the mobility problems."For that subset of patients, it works like magic," says Kim, who notes that Houston lags behind other cities in implanting such shunts, perhaps a sign doctors here aren't that aware of the benefit the device can provide.Many experts, however, say that more often than many conditions masquerade as Alzheimer's, they actually co-exist with the disease. It all complicates the "battle of wits" that Richard Elbein, president of the Houston chapter of the Alzheimer's Association, says goes into the sleuth work involved in diagnosis, a battle that often pits the doctor against a patient trying to hide their condition.A new kind of PET scan can reveal telltale amyloid plaques and tangles in the brain that characterize Alzheimer's, but because it's rarely covered by insurance thus far, it is still sparingly utilized by doctors. It can't confirm Alzheimer's because some patients with amyloid never develop the disease, but a negative scan can rule it out and prompt doctors to look for other explanations.But experts emphasize Alzheimer's is underdiagnosed far more than it's misdiagnosed, and Schulz acknowledges that unlike younger patients, if the patient is 80 or older, the diagnosis is likely to be correct. A recent international survey of more than 1,000 doctors who treat the disease found roughly half said the diagnosis "always" or "often" occurs too late to intervene in a meaningful way.The lesson: Seek out help at the first sign of cognitive impairment and don't accept diagnoses of mere "age-related forgetfulness.""The real story is that people in the early stages of disease aren't getting full work-ups," says Rachelle Doody, director of Baylor College of Medicine's Alzheimer's Disease and Memory Disorders Center. "People treated do better than those not treated, and a good specialist will rule out all the other possibilities before making a diagnosis of Alzheimer's."Source: http://www.chron.com/news/health/article/Difficulty-identifying-Alzheimer-s-makes-4062458.php