Peripheral Neuropathy Management: A Guide for Primary Care Clinicians
Peripheral neuropathy is a neurologic condition that affects approximately 8% of adults over the age of 55.1 Although it is one of the most common neurologic problems seen in the primary care setting, recognizing and evaluating peripheral neuropathy in a patient can be challenging due to its diverse presentations. Because peripheral neuropathy is associated with significant morbidity and decreased quality of life, it is imperative for primary care providers to efficiently diagnosis and manage patients with suspected neuropathy. In a recent review, Doughty and Sadjadi discussed a standardized approach to evaluate, diagnose, and manage a patient with suspected neuropathy.
Diagnosing a patient with peripheral neuropathy typically involves obtaining a thorough patient history, conducting a neurologic examination, and possibly confirming findings with nerve conduction studies and/or an electromyography (EMG).1 Use of neuroimaging and electrodiagnostic evaluation is debatable for most patients with suspected neuropathy, however, is recommended for patients where no definite diagnosis can be made.
Although assessing symptoms alone has a poor diagnostic accuracy, it is important for a provider to evaluate both the type of symptoms present as well as the pace of their progression.1 Table 1 lists common signs and symptoms seen in patients with peripheral neuropathy. Typically, sensory signs and symptoms present prior to motor and autonomic ones. Although rare, autonomic symptoms may be the most prominent or only symptoms a patient has which indicate neuropathy.
A neurologic examination is also a very important component in the diagnosis of peripheral neuropathy.1 Table 2 summarizes examination findings based on the type of peripheral neuropathy present. The provider should determine the anatomic areas affected, the degree of motor and sensory impairment, as well as the presence or absence of reflexes. The motor examination should assess weakness and/or muscle atrophy while the sensory examination should evaluate vibration, proprioception, pain, and temperature sensation. Screening tools that are often utilized during the examination include the Romberg sign to assess sensory ataxia, the 10-g Semmes-Weinstein monofilament to evaluate large fiber sensory dysfunction, and the 128-Hz tuning fork to evaluate vibratory sensation.
Following an established diagnosis of neuropathy, it is important for the provider to determine the underlying etiology of the disease.1 To exclude external factors, providers should begin by reviewing the patient's medications, family history, and occupational exposures, as well as consider screening for alcohol abuse. The diagnostic work-up and appropriate laboratory tests vary based on the type of neuropathy a patient has. For example, laboratory tests that are recommended for a patient with distal symmetric polyneuropathy include hemoglobin A1c and/or oral glucose tolerance test, vitamin B12, methylmalonic acid, serum protein electrophoresis with immunofixation, TSH, and a comprehensive metabolic panel complete blood count. If the initial work-up does not yield a definite diagnosis, additional testing tailored to the specific patient should be considered.