A syndrome of disabling fatigue variously labelled myalgic encephalomyelitis (ME), post-viral fatigue, or chronic fatigue syndrome (CFS)1 has received much recent attention(2,3). Depression occurs in up to half of hospital referrals with CFS4-f and in these cases, may explain the symptoms (7). However, despite suggestions of muscular dysfunction(8) the cause in the remainder is unknown. The following case is reported with reference to this question.
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Source: M C Sharpe, B A Johnson, and J McCann. Mania and recovery from chronic fatigue syndrome. J R Soc Med. 1991 Jan; 84(1): 51–52. PMCID: PMC1293060 http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1293060/