Polyneuropathy is a broad category of disorders that are caused by damaged nerves, particularly in the peripheral nervous system, the nerves that connect the brain to the body. Sensory nerves perceive sensations such as pain or pleasure; motor nerves connect to muscles and send signals that cause movement; and autonomic nerves control many unconscious processes, such as heart rate, blood pressure, bladder control and digestion. Polyneuropathy can cause many different symptoms depending on which types of nerves are damaged.
Sensation Changes
The longest nerves in the body reach to the feet and hands, and these nerves are often the first to become damaged in cases of polyneuropathy, explains the National Institute of Neurological Disorders and Stroke. The symptoms often begin with loss of sensation, numbness, tingling, or burning in the hands and feet, which spread up the arms and legs over time. As the condition progresses, the pain may intensify into sharp bolts of pain like electric shocks. The hands and feet may lose the ability to sense touch or temperature, meaning that cuts and burns may go unnoticed. In other cases, the hands and feet may become over-sensitive to touch, such that light touches cause severe pain.
Movement and Coordination Difficulties
If the motor nerves are damaged, many physical symptoms may develop, such as muscle weakness, loss of reflexes, fatigue and muscle twitching or cramping. People with severe polyneuropathy may have difficulty standing or coordinating arm movements, and muscle mass may decrease greatly. Some patients suffer complete paralysis of one or more body parts, such as the arms, legs or even the face. Speech may become impaired, as well as the ability to swallow, according to MayoClinic.com.
Body System Regulation Problems
Patients with polyneuropathy may develop problems controlling the bowel or bladder, such as constipation, diarrhea, urinary incontinence, difficulty starting urination or a sensation of an incompletely empty bladder. Changes in blood pressure may occur, leading to dizziness, lightheadedness and fainting. The body may lose the ability to sweat properly, which can result in problems of heat intolerance. Polyneuropathy may become life-threatening if the nerves controlling breathing or the heart beat become damage and cease functioning properly, Medline Plus explains.
References
- National Institute of Neurological Disorders and Stroke: Peripheral Neuropathy Fact Sheet
- Mayo Clinic: Peripheral Neuropathy
- Medline Plus: Peripheral Neuropathy
- University of Chicago Center for Peripheral Neuropathy: Chronic Inflammatory Demyelinating Polyneuropathy (CIDP)
- University of Maryland Medical Center: Chronic Inflammatory Polyneuropathy
