CASE STUDY

Case Study

Case Study

Question 1

Infectious conjunctivitis is inflammation of the conjunctiva usually caused by viruses or bacteria. A variety of microorganisms may infect the conjunctiva. The most common organisms are viral, particularly those from the group known as adenoviruses. Bacterial infections are less frequent. Both viral and bacterial conjunctivitis are quite contagious, easily passing from one person to another, or from a person's infected eye to the uninfected eye. Fungal infections are rare and occur mainly in people who use corticosteroid eye drops for a long time or have eye injuries involving vegetable matter.

Question 2

In John's case the culprit is the Haemophilus influenzae. The other three micro organism do not cause any problem to the eye. Whereas unencapsulated H. influenzae causes ear infections (otitis media), eye infections (conjunctivitis), and sinusitis in children and is associated with pneumonia. H aemophilus influenzae is responsible for a number of human diseases ranging from chronic respiratory infection to meningitis. Eight biotypes and six serotypes of H influenzae have been identified. Biotyping and serotyping have been used to investigate patterns of colonisation of H influenzae, as well as to identify strains of the bacterium that appear to be associated with more severe infection. Biotype I, serotype b, for instance, is often associated with severe meningitis in children.1 In contrast, non-serotypable strains of H influenzae, particularly biotypes II and III, are frequently commensal to the upper respiratory tract. While colonisation with biotypes II and III usually does not progress to disease, these same biotypes have been implicated in the pathogenesis of sinusitis, otitis media, acute and chronic exacerbations of lower respiratory tract infection, and acute and chronic conjunctivitis(Peake, 1994,, 230).

Question 3

Optrex infected eyes eye drops and eye ointment both contain the active ingredient chloramphenicol, which is a type of medicine called an antibiotic. Antibiotics are used to treat infections caused by bacteria. (NB. Chloramphenicol eye drops and ointment are also available without a brand name, ie as the generic medicine.) Chloramphenicol is known as a broad-spectrum antibiotic, which means it is effective against infections caused by a wide variety of bacteria. Chloramphenicol works by preventing bacteria from producing proteins that are essential to them. Without these proteins the bacteria cannot grow, replicate and increase in numbers. Chloramphenicol therefore controls the numbers of bacteria causing an infection, and the remaining bacteria die or are killed by the body's immune system. This treats the infection. Chloramphenicol is administered into the eye to treat a type of eye infection called bacterial conjunctivitis, which can be caused by various types of bacteria. Putting the medicine directly into the eye allows the chloramphenicol to act directly on the bacteria that are causing the infection(Jernigan, 1993,, 307).

Question 4

The toxic/allergic response is an over-reaction of the body's immune system to immunogens or allergens. The response can be innate or acquired. A variation of this over-reaction is manifested when the body responds hyperactively to exogenous materials such as medicines, contact lenses, contact lens solutions, dust, dander or viral ...