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Conjunctivitis case study: a lesson in history taking

Janet Webb
BSc(Hons) RGN DipN(Lond)
Practice Nurse
Lindum Medical Practice
Lincoln

I had considered my history-taking skills to be adequate, but my experience with this patient changed my mind and emphasised the need to take a wider view.
Mrs B is a 37-year-old housewife and mother of 5-year-old twin boys and a 12-year-old girl. She looks younger than 37, is marginally overweight and is a nonsmoking teetotaller. She first came to my triage clinic in June complaining of a sore, red and sticky left eye. She was not known to be atopic. She had had exactly the same symptoms some 4 months earlier and had been treated successfully with chloramphenicol 0.5% eyedrops. Her request was simply for more of the same.
Her symptoms had started the previous day with irritation and a sticky discharge. Her sight was unaffected, but now the eye was stinging, with crusting on her lashes. She did not wear contact lenses, never used cosmetics, and used only soap and water on her face. She had not changed any of her toiletries or detergent and did not use fabric softener. She went on to tell me her daughter had experienced similar symptoms a fortnight earlier, as had several of her classmates. Mrs B had been very careful to prevent crossinfection by maintaining strict hand hygiene after instilling her daughter's drops, and by using a separate flannel, towel and pillow-case for her.(1)
I prescribed her some more chloramphenicol 0.5% eyedrops, with directions to apply one drop to the left eye every 2 hours for that day, then reducing to four times daily and continuing for 48 hours after symptoms were cleared. Mrs Brett was confident in applying the drops; she was aware that burning, stinging or blurred vision might occur.
Courtenay and Butler describe conjunctivitis as "the most common eye disease worldwide".(2) In the absence of an atopic history, and with the unilateral symptoms and her two episodes occurring at different seasons, this would seem to be infective rather than allergic conjunctivitis. Although the viral variety is more common, and usually occurs in epidemics, which would account for her daughter's infection, I suspected Mrs Brett of having bacterial conjunctivitis. Rosen advises that the two types can be diagnosed from history, the bacterial type presenting with "the classic sticky eye", and the viral type associated with a watery, itchy eye, often accompanied by sore throat and cold symptoms.(3) The bacterial disease is most commonly caused by staphylococcal infection.(2)
Either way, bacterial or viral, both respond to chloramphenicol, which is therefore the drug of choice (according to the British National Formulary [BNF]). The rationale is to provide clinical improvement in bacterial, or give relief of symptoms while preventing secondary bacterial infection in viral, conjunctivitis.(2) I advised Mrs B to return if her symptoms had not improved in a week.
I did not see Mrs Brett again until late August, with yet another recurrence of the conjunctivitis, this time affecting the right eye. Her having had no history before the February episode, then having three infections in a 6-month period, I asked if anything had changed in any other aspect of her health at the same time. She replied yes. She had been found to be mildly hypertensive in her last pregnancy, and had been monitored since then, but only started treatment with ramipril, an angiotensin-converting enzyme (ACE) inhibitor, in late January. Blood pressure monitoring and urea and electrolyte assay had been within normal ranges since then. On checking the side-effect profile for ramipril, I quickly discovered conjunctivitis listed (BNF 46, p. 94).
With Mrs B's agreement I discussed this connection with her GP, and her prescription was changed to lisinopril. I arranged for Mrs B's blood pressure - and her eye - to be checked the following week and then a month later: all was well.
With hindsight, I should have discovered the cause of her conjunctivitis earlier, and could have prevented the third episode if I had taken a full history. It is not an omission I shall repeat!

References

  1. Johnson G, Hill-Smith I, Ellis C. The minor illness manual. Oxford: Radcliffe Medical Press; 1997.
  2. Courtenay M, Butler M. Essential nurse prescribing. London: Greenwich; 2002.
  3. Rosen E. The acute red eye. A booklet produced by Leo Laboratories Ltd (undated).