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Cystic fibrosis (CF) has been transformed from a fatal diagnosis in infancy to a chronic disease of children and young adults. Symptom patterns and disease burden in CF may be shifting to reflect the relatively healthier, older population with the disease. Self-management of symptoms is a hallmark of chronic illness, and yet we do not have a good understanding of how CF patients monitor or manage their symptoms. Children and adults were recruited through clinics in three Canadian provinces. Questionnaires with open-ended and close-ended questions in English and French, designed to assess the frequency, severity, and self-management of pain, breathlessness, and cough, were mailed to all the eligible participants. One hundred twenty-three respondents completed the survey, for a response rate of 64%. Eighty-four percent (103 of 123) of participants reported having pain. They reported an average of 2.1 locations of pain, with headache and abdominal pain most frequently described. Sixty-four percent (76 of 123) of participants reported having breathlessness, and 83% (99 of 123) of participants reported experiencing cough. Sixty-three percent (62 of 99) of participants with cough reported that cough always or sometimes interfered with their sleep. A variety of pharmacological and nonpharmacological treatments were used to manage symptoms. Pain and dyspnea are more common than suspected and a wide variety of pharmacological and nonpharmacological measures are used to treat symptoms. Cough is difficult to assess, but disturbed sleep may be an indicator of cough severity and an important symptom to consider when evaluating the overall burden of illness in those with CF.

Parietal, insular and anterior cingulate cortices are involved in the processing of noxious inputs and genesis of pain sensation. Parietal lesions may generate central pain by mechanisms generally assumed to involve the 'medial' pain system (i.e. medial thalamic nuclei and anterior cingulate cortex (ACC)). We report here PET and fMRI data in a patient who developed central pain and allodynia in her left side after a bifocal infarct involving both the right parietal cortex (SI and SII) and the right ACC (Brodmann areas 24 and 32), thus questioning the schematic representation of cortical pain processing. No rCBF increase was found in any part of the residual cingulate cortices, neither in the basal state (which included spontaneous pain and extended hypoperfusion around the infarct), nor during left allodynic pain. Thus, as previously observed in patients with lateral medullary infarct, neither spontaneous pain nor allodynia reproduce the cingulate activation observed after noxious pain in normal subjects. Conversely, both PET and fMRI data argue in favour of plastic changes in the 'lateral discriminative' pain system. Particularly, allodynia was associated with increased activity anteriorly to the infarct in the right insula/SII cortex. This response is likely to be responsible for the strange and very unpleasant allodynic sensation elicited on the left side by a non-noxious stimulation.

Turning attention towards or away from a painful heat stimulus is known to modify both the subjective intensity of pain and the cortical evoked potentials to noxious stimuli. Using PET, we investigated in 12 volunteers whether pain-related regional cerebral blood flow (rCBF) changes were also modulated by attention. High (mean 46.6 degrees C) or low (mean 39 degrees C) intensity thermal stimuli were applied to the hand under three attentional conditions: (i) attention directed towards the stimuli, (ii) attention diverted from the stimuli, and (iii) no task. Only the insular/second somatosensory cortices were found to respond whatever the attentional context and might, therefore, subserve the sensory-discriminative dimension of pain (intensity coding). In parallel, other rCBF changes previously described as 'pain-related' appeared to depend essentially on the attentional context. Attention to the thermal stimulus involved a large network which was primarily right-sided, including prefrontal, posterior parietal, anterior cingulate cortices and thalamus. Anterior cingulate activity was not found to pertain to the intensity coding network but rather to the attentional neural activity triggered by pain. The attentional network disclosed in this study could be further subdivided into a non-specific arousal component, involving thalamic and upper brainstem regions, and a selective attention and orientating component including prefrontal, posterior parietal and cingulate cortices. A further effect observed in response to high intensity stimuli was a rCBF decrease within the somatosensory cortex ipsilateral to stimulation, which was considered to reflect contrast enhancing and/or anticipation processes. Attentional processes could possibly explain part of the variability observed in previous PET reports and should therefore be considered in further studies on pain in both normal subjects and patients with chronic pain.