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The words ‘missing links’ may bring to mind thoughts on evolution, apes, near-humans and the origin of the species. But in day-to-day medical practice missing links can be the cause of significant and serious medical conditions. These links, or factors, when discovered and put back into place will bring about the reversal of all, or most, ill effects caused by the absence of that vital link and make a sick person healthy.
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The effects and changes caused by the missing factors may be insidious, may take a long time to reveal obvious clinical signs, are easily missed and often embarrass the unwary observer. The resulting conditions may come to light in people that you know well and see frequently, and who have complete faith in your capabilities and clinical acumen.
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Mrs S, in her fifties, had not had a comfortable life. She had nine children, not all of them easy to manage, and had become a grandmother at an early age with added caring responsibilities. Her husband had always been a heavy drinker and at an early age developed Parkinson’s disease, with total incapacity.
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Understandably, I thought, she always seemed to be tired, to have difficulty with weight and to be depressed. Because of her various involvements, I saw Mrs S frequently and sympathised with her feelings and predicament. I failed to notice that she felt the cold easily, and that her voice was getting deeper and her hair coarser. It was not until I noticed her change in features from Mrs Jekyll to Mrs Hyde that the penny dropped. Appropriate investigations and correct treatment quickly followed. The thyroxine worked like magic, and we saw the return of the Mrs S we all used to know. Myxoedema can trap even the experienced observer.
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On a visit to Mrs S several months later I thought her features were a bit coarse, and she said she had been having weight problems again. A check on her thyroid function tests showed that her thyroid needs had increased. Be ever watchful.
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Sometimes the illness caused by the missing link can be life threatening, suddenly and dramatically.
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Laura was a pretty 13-year-old, full of energy and a strong tennis player. She was one of three children in a happy family. Her brother, three years older, had been blind from birth and had become epileptic at an early age. Laura presented on a Monday afternoon with persistent vomiting, and as there was a lot of vomiting of viral aetiology in children of the district she was diagnosed as having viral gastroenteritis. Her condition did not improve and I saw her on Friday of that same week. As we went carefully over the history I could not help but notice that Laura was falling asleep upright in the chair, ready to topple over.
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‘How long has she been like this?’
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‘Has she been passing much urine?’
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‘She never seems to stop.’
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‘Before the vomiting episode, was she drinking a lot?’
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‘We kept running out of soft drink, cordial and fruit juice.’
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‘She’s been very tired—she couldn’t even be bothered with her beloved tennis.’
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A quick blood sugar showed a sky-high level; a ketotic Laura was admitted to hospital that afternoon. By Monday morning she was back home, well and self-injecting with insulin twice daily. She was her old self, having accepted her missing link philosophically.
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As we know, when the particular factor or link goes missing in such cases as myxoedema, diabetes mellitus, pernicious anaemia and Addison’s disease, we have a serious, life-threatening, often insidious disease evolving. The recognition of the missing link and its immediate replacement will bring about a miraculous recovery that has the patient saying, ‘Doctor, I’ve never felt better in my life’.
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DISCUSSION AND LESSONS LEARNED
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There are common conditions that occur because of a missing link in our complicated biochemical mechanisms, and which present as beautiful clinical entities before a vigilant observer.
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Every day in our patient contacts there may be a missing link for us to discover and identify and we must do our utmost to ensure that we never miss that vital link.