The Clinical journal of pain
-
In this review, we explain our current understanding of the molecular basis for pain relief by capsaicin and other transient receptor potential vanilloid subfamily, member 1 (TRPV1) agonists. We summarize disease-related changes in TRPV1 expression and its implications for therapy and potential adverse effects. Last, we provide an overview of the current clinical uses of topical and injectable TRPV1 agonist preparations in both oncologic and nononcologic populations. ⋯ We argue that TRPV1 agonists and antagonists are not mutually exclusive but rather complimentary pharmacologic approaches for pain relief and we predict a "revival" for capsaicin and other TRPV1 agonists in the clinical management of pain associated with inflammation, metabolic imbalances (eg, diabetes), infections (HIV), and cancer, despite the current focus of the pharmaceutical industry on TRPV1 antagonists.
-
Although there have been a few case reports in the literature of self-inflicted symptoms presenting as complex regional pain syndrome (CRPS), there has been no systematic study. This report investigates the period prevalence and characteristics of self-induced disorders in patients referred to a comprehensive pain clinic with a diagnosis of CRPS. ⋯ This is the first report of a case series of patients diagnosed as CRPS with self-induced symptoms. We discuss in detail limitations of the study, factors that contribute to the index of suspicion, and the complex nature of the behavior including the overlap between factitious disorder, somatoform disorders, and malingering, whereas we stress the legitimacy of CRPS as a diagnosis.
-
Sensory hypersensitivity, central hyperexcitability [lowered nociceptive flexion reflex (NFR) thresholds], and psychologic distress are features of chronic whiplash. However, relationships between these substrates are not clear. This study tested the hypothesis that psychologic distress and catastrophization are correlated with sensory hypersensitivity and NFR responses in chronic whiplash. ⋯ We have demonstrated that psychologic factors have some association with sensory hypersensitivity (cold pain threshold measures) in chronic whiplash but do not seem to influence spinal cord excitability. This suggests that psychologic disorders are important, but not the only, determinants of central hypersensitivity in whiplash patients.
-
To explore clinical findings in men with chronic pain after falanga torture as compared with controls, and to try to understand the nature of the pain mechanisms responsible. ⋯ We found clear clinical signs of nerve injury in the feet. The sensory findings indicated 2 neuropathic pain mechanisms, one dominated by a peripheral pain generator and other by irritative phenomena (dysesthesia, allodynia), indicating central sensitization. It is reasonable to assume that these changes are due to the falanga exposure. A nociceptive contribution cannot be excluded. It is important to perform an individual diagnostic analysis to facilitate adequate treatment.