Chronic neuropathic pain

Definition

Chronic neuropathic pain is chronic pain caused by a lesion or disease of the somatosensory nervous system [1]. The somatosensory nervous system provides information about the body including skin, musculoskeletal and visceral organs. A lesion or disease causing neuropathic pain may involve peripheral or central structures of the somatosensory nervous system. Persistence or recurrence over ≥ 3 months defines chronic pain (see 6 Temporal Properties). The pain may be spontaneous (continuous or episodic) or evoked, as an increased response to a painful stimulus (hyperalgesia) or a painful response to a normally nonpainful stimulus (allodynia). The diagnosis of neuropathic pain requires a history of nervous system injury, for example, a stroke or nerve trauma, or disease, for example, diabetic neuropathy, and a neuroanatomically plausible distribution of the pain [2]. Negative (for example, decreased or loss of sensation) and positive sensory symptoms or signs (for example, allodynia or hyperalgesia) must be compatible with the innervation territory of the affected nervous structure. Demonstration of the lesion or disease involving the nervous system, for example, by imaging techniques neurophysiological or laboratory tests, confirms the diagnosis of definite neuropathic pain [2]. Neuropathic pain is a major source of physical impairment, emotional and psychosocial distress [3], and requires multimodal treatment with a specific pharmacological component [4, 5]. Diagnostic Criteria: For the diagnosis of chronic neuropathic pain, pain must persist or recur for ≥ 3 months and fulfill at least criteria A and D below. Criteria B and C increase the level of diagnostic certainty. A. The pain is characterized by both of the following: A.1 History of relevant neurological lesion or disease A.2 Pain distribution neuroanatomically plausible B. Pain is associated with sensory signs in the same neuroanatomically plausible distribution C. Diagnostic test confirming a lesion or disease of the somatosensory nervous system explaining the pain D. Not better accounted for by another diagnosis of chronic pain. Comments Negative or positive sensory signs consistent with the distribution of the pain may be sufficient to indicate the presence of a lesion or disease of the peripheral somatosensory nervous system. The clinical examination may be supplemented by laboratory tests, e.g., quantitative sensory testing. Tests that reveal the relevant lesion or disease affecting the somatosensory system may, e.g., consist of surgical or radiological confirmation of nerve compression, nerve conduction study, laser-evoked potentials, blink reflex, or skin biopsy confirmation of reduced nerve fibre terminals. Positive findings in these investigations may provide important diagnostic hints at the source of pain. However, all clinical and diagnostic aspects of the pain need to be considered before assuming causality. If clinical examination or diagnostic testing are performed, and the results are negative, neuropathic pain is unlikely (or less likely). Consider using another chronic pain diagnosis.

Subcategories (2)