Susan, a 39-year-old fashion designer, presented because of very severe pain in her lower back and legs. The problem followed a febrile illness of sudden onset following a recent business trip to Singapore and Thailand. She had attributed the pain to a recurrence of an old problem of sciatica and was concerned that she may have been infected with swine flu. Two days before our appointment, she had visited an emergency department for pain relief and was prescribed oxycodone because Panadeine Forte was ineffective. She said that now the pains in her legs were unbearable and not responding well to opioids. Further detailed history revealed that she had associated fever, malaise, nausea, headache and generalised muscular aching. She also admitted to feeling very depressed—even suicidal. On physical examination there were no specific musculoskeletal or neurological signs (despite the severe pain), just a temperature of 38.2 °C.
As tears streamed from her eyes describing the unbearable pain in her thighs and lower back, the term ‘breakbone fever’ went through my mind. Blood tests confirmed dengue fever which is caused by a flavivirus transmitted by the Aedes mosquito.
DISCUSSION AND LESSONS LEARNED
Dengue fever is widespread in the south-east Pacific and endemic in Queensland. A returned traveller with myalgia and fever < 39 °C is more likely to have dengue than malaria.
A similar tropical infectious disease is chikungunya, which should be considered.
We should use caution with opioids in diseases causing temporary myalgia.
Depression with suicide has been reported in troops with dengue fever fighting in the tropics.
THE PAINFUL KNEE: SEARCH NORTH
Tom B, a 51-year-old timber worker, presented for yet another opinion about his painful right knee. The knee had been getting increasingly painful for about two years and now the pain was so severe he could not complete a day’s work. Apart from being considerably overweight, Tom looked fit and well.
I could not detect any abnormality around the medial aspect of the knee where Tom claimed to experience ‘terrible pain’. An accompanying X-ray of his knee was normal. He said that he had visited three doctors, including a specialist who said that his knee probably had early osteoarthritis. NSAIDs had helped but not in the past few weeks. I wondered about nerve entrapment or referred pain from his spine (L3) but could not find any abnormality.
I referred Tom to an orthopaedic specialist as I had known Tom from my days in the bush and believed that his pain was genuine. The specialist rang me and said, ‘You’ve fallen for the old trap. He has severe osteoarthritis of the hip and will need a hip replacement. You should have known better.’ Tom was a very happy person when surgery of the hip relieved the pain in his knee!