Towards a Cheap and Easy Way to Monitor HIV/AIDS

July 2005 | Volume 2 | Issue 7 | e238 | e242 Postherpetic neuralgia (PHN) is a chronically painful condition that is a complication of shingles (acute herpes zoster), a recurrence of the varicellazoster virus, which initially causes chickenpox. Although shingles usually resolves within a month, some people continue to feel the pain of PHN long after the rash and blisters heal, because of nerve damage (neuropathic pain) caused by the shingles. Not everyone who has had shingles develops PHN, although it is a common complication of shingles in older adults. Despite advances in antiviral therapy during acute herpes zoster and the more recent introduction of vaccination against varicella zoster, PHN continues to be a signifi cant clinical problem, with 10–20% of patients developing persistent neuropathic pain after acute herpes zoster reactivation. The nature of PHN pain is variable, which implies that a variety of mechanisms might be operating. This variability has led to the hypothesis that treatment plans could be optimised for individual patients on the basis of the individual pattern of their symptoms or the underlying mechanism of the pain. However, the current evidence base for therapies in PHN is based on clinical trials of analgesics, which have examined PHN as a single disease entity. Furthermore, there is little evidence for the effi cacy of drugs for specifi c sets of symptoms and no simple way to determine which pain mechanisms might be operating in an individual patient. In this month’s PLoS Medicine, Andrew Rice and colleagues reassessed the evidence base by doing a systematic review and meta-analysis of analgesic therapy for PHN, which has fundamentally changed in the wake of several major new trials. The authors searched the literature for trials of PHN and retrieved 62 articles, of which 35 were kept for fi nal analysis. Their analysis confi rmed several previous research fi ndings, although they cautioned that the meta-analytic study design of collecting data from a range of trials had several inherent pitfalls, and it is diffi cult to directly compare treatments across different trials. However, they found evidence for analgesic effi cacy in established PHN for Which Treatment for Postherpetic Neuralgia?