**9. Modification to initial therapy**

The medical response of mycobacterial keratitis to antibiotic therapy can be achieved by con‐ stant clinical observance. This can be difficult to appreciate in the first days of treatment due to increase in inflammation and local reaction to topical agents. The clinical response varies de‐ pending on the microorganism and pathogenicity of the mycobacteria, duration of the infec‐ tion, risk factors involved and the patient's individual response (immunosuppresion).

**Figure 10.** Patient 4 presented in the first clinical examination a paracentral infiltrate caused by Mycobacteria chelo‐ *nae*. Previous to initiation of proper antibiotic treatment. At this moment visual acuity was count fingers 2 meters.

If the chosen therapy is effective, some response should manifest within the first of 24 to 72 hours of appropriate treatment. [Figure 10,11]. Said response manifests with the decrease of stromal infiltrates and less anterior chamber inflammation in case it exists. [Figure 12, 13]

**Suggested treatment**

The medical response of mycobacterial keratitis to antibiotic therapy can be achieved by con‐ stant clinical observance. This can be difficult to appreciate in the first days of treatment due to increase in inflammation and local reaction to topical agents. The clinical response varies de‐ pending on the microorganism and pathogenicity of the mycobacteria, duration of the infec‐

**Figure 10.** Patient 4 presented in the first clinical examination a paracentral infiltrate caused by Mycobacteria chelo‐ *nae*. Previous to initiation of proper antibiotic treatment. At this moment visual acuity was count fingers 2 meters.

tion, risk factors involved and the patient's individual response (immunosuppresion).

2. Fourth-generation fluoroquinolone (gatifloxacin)

*\* In case of resistance addition of Rifampin 30mg/mL.*

*Topical* 1. Amikacin 20 mg/mL

*Systemic* 3. Clarithromycin 500mg PO BID

1. Flap lift and irrigation 2. Flap amputation in post-LASIK

3. Biopsy and culture 4. Penetrating keratoplasty

**Table 8.** We suggest a triple antibiotic treatment combined if needed with surgical therapy.

Triple Antibotic Therapy

162 Common Eye Infections

SurgicalTherapy

**9. Modification to initial therapy**

**Figure 11.** Patient 4 at 3 months follow-up after proper antibiotic treatment was applied. Final visual acuity was 20/30.

**Figure 12.** Patient 1 with preceding hypopyon (black arrow) and anterior chamber reaction who underwent a thera‐ peutic flap amputation procedure.

**Figure 13.** Absence of ahypopyon seen in Patient 1 as a manifestation of positive response to antibiotic treatment.

If clinical improvement exists at 48 hours of initiation of treatment, we encourage to contin‐ ue the same pharmacological agents, reducing the administration time to 1 drop every 2 hours until completion of 5 days with night rest. After the 5 days, if further improvement exists, antibiotic doses should be decreased progressively in function of clinical response, drug tolerance and sensitivity tests results. Antibiotic with the best sensitivity should be the one chosen to continue the treatment for 2-3 more weeks.

Special caution should be kept when therapy is suspended, as some microorganisms may remain in corneal tissue. In this case, a prolonged treatment may be required.

If lesion progression occurs after 48 hours of initiation of treatment, manifested by evident increase in size, stromal thinning or incomplete resolution of symptoms, the ophthalmolo‐ gist should consider a lack of sensitivity to the chosen treatment or a failure in the patient's attachment to the therapy. Culture results should be rechecked as well as sensitivity test re‐ sults, as an addition of a different antimicrobial agent might be needed.[Table 9]


**Table 9.** Response parameters associated with antibiotic therapy
