OCULAR TUBERCULOSIS

    OCULAR  TUBERCULOSIS

DEF-

Chronic granulomatous infection caused by tubercle bacilli

• Mycobacterium bovis [ bovine]- by milk
• Mycobacterium tuberculosis [human]- droplet inf

MORPHOLOGY-

• Slender rods with branching filamentous forms
• Resemble fungal mycelium ,so k/as mycobact i.e fungus like bacteria
• Do not stain readily , but once stained resist decolourisation with dilute mineral acid – k/as Acid fast
• Aerobic
• Non-motile
• N0n-capsulated
• Non-sporing
• Slow growth

    PATHOGENESIS-

       Inhalation of aerosolized droplets→ Asymptomatic , self-limited pulmonary granuloma→ resolves & becomes dormant→ reactivates later→ disseminates to other organs.

OCULAR TB-

CONJ-

• Phlyctenular c’vitis- small, grey –yellow nodules on bulbar conj near limbus
• Prod refex lacrimation

CORNEA-

• Phlyctenular keratitis
• Fascicular ulcer-
• Phlyctenular ulcer migrates slowly from the limbus to the centre of the cor in a serpiginious way.
• It carries a leash of BVs  which lie in a shallow gutter formed by the ulcer.
• Superficial allergic type of ulcer
• Never perforates
• When the ulcer heals, the BVs attenuate with a dense cor opacity near the apex of the ulcer

UVEA-

• Tuberculous iritis

1. Metastatic [granulomatous]-

• Miliary-small ,yellowish white nodule surrounded by small

               Satellites near the pupillary or ciliary margin

• Conglomerate- Larger, yellowish white tumor

                          - smaller satellites may be present

                          - Nodules contain giant cells

2. Exudative [non-granulomatous]

• Tuberculous choroiditis-Tubercles

                                          -Tuberculomas

Tubercles-Post pole

              - Solitary/multiple

              -Multifocal

             -0.3-3mm dia

             -  Yellowish, grayish or white

             -overlying serous RD

Tuberculomas- Solitary

                      -Grayish white

                      -Raised

                      -2-3 DD

                      -Overlying exud RD

RETINA-

Eale’s disease [retinal periphlebitis]-

• recurrent VH
• young healthy adult males
• Periphlebitis→ intraretinal h’age→vascular tortuousity & collaterals→ NV

INV-

1. Sputum exam for AFB
2. Chest X-ray
3. Montoux test
4. Anticord factor antibody

T/T-

5 anti-TB drugs

1) ISONIAZID [H]- 5mg/kg

s/e – optic neuritis

• hepatitis

2) RIFAMPICIN [R]- 10mg/kg

S/E –Hepatitis

     -  Red –orange urine

3) STREPTOMYCIN [S]-15mg/kg

S/E- Ototoxic

• Nephrotoxic

  4) ETHAMBUTOL [E]- 20mg/kg

  S/E- ON

       -Red-green colour blindness

5. PYRAZINAMIDE [Z]-25mg/kg

    S/E –Hepatitis

          -Hyperuricemia