Symptoms of Grover's disease include small, itchy red bumps that appear in groups and blister, according to the National Association for Rare Disorders. The blisters usually contain a thin, watery liquid and occur near hair follicles. A swollen, red border encircles each group of blisters.
Most outbreaks of Grover's disease occur on the back and chest, but breakouts sometimes appear on the sides of the arms and legs, reports the National Association for Rare Disorders. The condition can last anywhere from a few weeks to several months.
Doctors diagnose Grover's disease by looking at skin cells under a microscope, notes the National Association for Rare Disorders. A positive diagnosis for the rare condition is indicated if the doctor confirms an absence of the connective substance that holds skin cells together. Over time, the condition causes skin cells to separate.
Researchers aren't sure exactly what causes Grover's disease, says the National Association for Rare Disorders. Some doctors believe it may be associated with sun damage, while others think it could be linked to sweating and heat. Doctors have associated cases with parasitic follicle mites, hot tubs and long-term confinement to bed. Grover's disease primarily affects men over the age of 40. Although not as common, the disease is also found in women.