Ligneous Conjunctivitis
Ligneous conjunctivitis is a rare, chronic, and severe form of eye inflammation that primarily affects the conjunctiva, the thin, transparent tissue that lines the inside of the eyelids and covers the white part of the eyeball. This condition is characterized by the formation of woody, hard, and brownish lesions or plaques on the conjunctiva, which may cause discomfort, redness, and vision problems.
Causes
Ligneous conjunctivitis is usually associated with an underlying systemic disorder that causes an imbalance in the fibrinolytic system, which is responsible for breaking down fibrin, a protein involved in blood clotting. The two most common causes are:
- Plasminogen Deficiency:
- The most well-known and common cause of ligneous conjunctivitis is plasminogen deficiency, a rare genetic disorder in which the body has insufficient plasminogen, a protein necessary for the breakdown of fibrin. This results in abnormal accumulation of fibrin in tissues, leading to the formation of woody plaques in the conjunctiva and other mucosal surfaces (such as the mouth and airway).
- Systemic Conditions:
- Ligneous conjunctivitis may also be seen in certain conditions that predispose individuals to abnormal clotting or fibrin deposition. These include:
- Systemic lupus erythematosus (SLE), an autoimmune disorder
- Rheumatoid arthritis and other autoimmune diseases
- Chronic infections or drug reactions that affect the immune system or clotting pathways.
Symptoms
The primary symptoms of ligneous conjunctivitis include:
- Redness and irritation in the eyes
- Formation of hard, woody plaques or lesions on the conjunctiva
- Increased mucus production and discharge
- Dryness or sensation of a foreign body in the eye
- Vision problems in severe cases, including blurred vision or partial blindness if untreated
These plaques are typically brownish or yellowish, and they may grow larger and spread over time. In some cases, these lesions may cause the eyelids to become sticky or may lead to secondary infections.
Diagnosis
Diagnosing ligneous conjunctivitis involves:
- Clinical Examination:
- The distinctive woody lesions on the conjunctiva are often sufficient for a preliminary diagnosis. An ophthalmologist will examine the eye to identify these characteristic plaques.
- Blood Tests:
- Plasminogen levels can be measured to confirm a deficiency, which is typically found in patients with ligneous conjunctivitis caused by plasminogen deficiency.
- Histopathology:
- A biopsy of the conjunctival lesion may show fibrin deposition and the presence of plasma cells, helping to confirm the diagnosis.
- Genetic Testing:
- In cases where plasminogen deficiency is suspected, genetic testing can help confirm the presence of mutations in the PLG gene, which codes for plasminogen.
Treatment
The main goal in treating ligneous conjunctivitis is to address the underlying cause (plasminogen deficiency or associated systemic disorders) and manage the symptoms of the eye condition. Treatment options include:
- Plasminogen Replacement Therapy:
- For patients with plasminogen deficiency, plasminogen replacement therapy is the most effective treatment. This may involve topical plasminogen (applied directly to the eye) or intravenous plasminogen infusion to restore normal fibrinolytic activity and help break down the fibrin deposits in the conjunctiva.
- Anti-inflammatory Medications:
- Corticosteroids or other immunosuppressive drugs may be used to reduce inflammation in the conjunctiva and prevent further tissue damage.
- Surgical Removal of Lesions:
- In some cases, surgical removal of the woody plaques may be necessary if they cause significant discomfort or interfere with vision. However, the plaques may recur, requiring ongoing management.
- Management of Underlying Conditions:
- For patients with systemic conditions (e.g., lupus, rheumatoid arthritis), treating the underlying disease with appropriate immunosuppressive or anti-inflammatory medications is essential to control inflammation and prevent further conjunctival damage.
Prognosis
With early and proper treatment, the progression of ligneous conjunctivitis can often be slowed or halted. However, without intervention, the condition can cause persistent eye problems, including vision loss due to the recurrent formation of plaques. The overall prognosis depends on the severity of the disease, the response to treatment, and the presence of any underlying systemic conditions.
