Diagnosis Sometimes pneumonia is hard to diagnose because it may cause symptoms commonly seen in people with colds or the flu. You may not realize it's more serious until it lasts longer than these other conditions. Your doctor will diagnose pneumonia based on your...

General Information About Plasma Cell Neoplasms KEY POINTS Plasma cell neoplasms are diseases in which the body makes too many plasma cells. Plasma cell neoplasms can be benign (not cancer) or malignant (cancer). There are several types of plasma cell neoplasms....

What is AMD? AMD is a common eye condition and a leading cause of vision loss among people age 50 and older. It causes damage to the macula, a small spot near the center of the retina and the part of the eye needed for sharp, central vision, which lets us see objects...

What is Clostridium difficile?  Clostridium difficile is a Gram-positive, spore-forming bacterium. It is an opportunistic pathogen, infecting the colon of patients following antibiotic treatment. C. difficile produces two toxins, TcdA and TcdB, which damage intestinal...

What is narcolepsy? Narcolepsy is a chronic neurological disorder that affects the brain’s ability to control sleep-wake cycles.  People with narcolepsy usually feel rested after waking, but then feel very sleepy throughout much of the day.  Many individuals with...