**6. Conclusion**

**Figure 6.** Severe infectious conjunctivitis and a Gram-stained panoramic image of the discharge sample. A: A large quantity of yellowish-white mucopurulent discharge and conjunctival hyperaemia were found. B: A large amount of

**Antimicrobial Max MIC Min MIC % Susceptible\***

Nolfloxacin 256 0.25 25 Ciprofloxacin 32 0.032 25 Levofloxacin 32 0.064 25 Gatifloxacin 32 0.016 40 Moxifloxacin 32 0.016 40 Erythromycin 256 0.016 45 Chloramphenicol 256 2 55 Gentamicin 16 0.064 95 Tobramycin 32 0.064 90 Doxycycline 4 0.064 100 Imipenem 0.08 0.016 100 Ceftriaxson 0.5 0.125 100 Vancomycin 0.5 1 100 Teicoplanin 0.125 1 100

Gram-positive rods and a few polymorphonuclear leukocytes were found.

80 Infection Control

\*: The susceptibility test follow the instruction of E-test.

**Table 1.** MICs of several antimicrobials to 20 bacterial strains. (μg/mL)

When faced with the case of an elderly patient with chronic conjunctivitis, the first step should be to collect the discharge and to prepare a Gram stained smear and observation un‐ der microscope. Assessment should also determine whether the lacrimal duct is obstructed or not. Documenting a patient's history of antimicrobial use will also contribute to the diag‐ nosis. If the patient has a history of using an antimicrobial ophthalmic solution, and also has Gram-positive rods in palisade, ring or 'N, T, V, W, or Y' letter-shaped arrangement present in their discharge and if these Gram positive rods appear to be ingested by polymorphonu‐ clear leukocytes, then a cephem-based ophthalmic solution should be prescribed first. It is possible that an organism other than a *Corynebacterium* species is the causative pathogen if the cephem antibiotics do not resolve the infection. For *Corynebacterium*-induced keratitis, a systemic carbapenem and glycopeptide may be useful in additions to frequent applications of cephem, aminoglycoside, and glycopeptide eye drops.
