Peripheral Ulcerative Keratitis
Ulcerative Keratits is a group of inflammatory diseases whose final common pathway is peripheral corneal thinning.
Corneal Ulcer, Unspecified (ICD9 370.00)
Peripheral Ulcerative Keratits (PUK) is a group of inflammatory diseases whose final common pathway is peripheral corneal thinning.
PUK has an incidence of 3 cases per million per year. There is an equal prevalence of males and females. PUK has been associated with many autoimmune disorders, including:
• Rheumatoid Arthritis, present in 34 – 42% of PUK patients
• Polyarteritis Nodosa
• Inflammatory Bowel Disease
• Collagen vascular diseases
o Systemic Lupus Erythematosus (SLE)
o Relapsing Polychondritis
o Progressive Systemic Fibrosis,
• ANCA vasculitides
o Wegener’s Granulomatosus
o Churg – Strauss
o Microscopic Polyangiitis
PUK is associated with autoimmune disorders, as described above.
Peripheral Ulcerative Keratitis occurs when immune complexes activate the complement system resulting in chemotaxis of inflammatory cells (neutrophils & macrophages). These neutrophils and macrophages release collagenase and protease that destroy corneal stroma. Proinflammatory cytokines induce stromal keratocytes to produce matrix metalloproteases which contribute to the breakdown of the cornea.
There are several theories as to the etiology of Peripheral Ulcerative Keratitis. The disease may be an autoimmune reaction to corneal antigen. In Mooren’s Ulcer, unregulated helper Th1 cells have been shown to produce autoreactive antibodies. The disease may also be caused by circulating immune complex deposition. Dysregulated production of autoreactive antibodies in autoimmune disease promotes the Th2 response. Finally, PUK may be a hypersensitivity reaction to exogenous antigens.
Patients may present with pain, redness, tearing, photophobia, and decreased vision. They may also have a history of autoimmune disorders as described above.
Evaluation of patients with suspected peripheral ulcerative keratitis includes a complete ophthalmological exam. The Ophthalmologist will assess patient’s vision, intraocular pressure, pupils, and examine the eyes with a slit lamp. Examination will focus on the peripheral cornea to assess the degree of involvement, depth of corneal thinning, extent of epithelial defect, and degree of inflammation.
The appearance of peripheral cornea will be dependent upon the severity of corneal thinning. Progressive thinning may lead to descemetocele formation and corneal perforation.
The image to the right shows a peripheral ulcer that has progressed to perforation. Note the peaked pupil and prolapse of iris tissue at the 4 - 5 o'clock position. Also note the injection surrounding the crescentric area of thinning.
Patients may present with pain, redness, tearing, photophobia, and decreased vision.
Diagnosis is based on history and physical. Patients should also be evaluated for underlying systemic autoimmune disease.
Diagnosis is based on history and physical as outlined above. Corneal scrapings for cultures may be done if an infectious etiology is suspected. An ultrasound of the eye (B-scan) may be performed to evaluate for posterior scleritis. 36% of patients with PUK also have scleritis.
Systemic evaluation for underlying autoimmune diseases may include:
• Complete Blood Count (CBC)
• Complete Metabolic Profile (CMP)
• Urinalysis with microscopic analysis (UA & micro)
• Antinuclear Antibody (ANA)
• Anti-Neutrophil Cytoplasmic Antibody (ANCA)
• Rheumatoid Factor (RF)
• Anti-Cyclic Citrullinated Peptide (anti-CCP)
• Rapid Plasma Reagin (RPR)
• Fluorescent Treponemal Antibody (FTA-Abs)
• Chest X-Ray (CXR)
• Purified Protein Derivative (PPD)
• Sacroiliac joint X-Ray
• CAT scan of sinuses
• Hepatitis B Visus
• Hepatitis C Virus
• Corneal Culture
• Ultrasound of the eye
The differential diagnosis of Peripheral Ulcerative Keratitis is broad. It includes other inflammatory conditions such as Mooren’s Ulcer and Rheumatoid Furrow as well as degenerative conditions such as Terrien’s Marginal Degeneration, Senile Furrow Degeneration, or Pellucid Marginal Degeneration. Infectious or neoplastic etiologies such as corneal ulcer or carcinoma in situ are also in the differential.
The primary goals in the treatment of peripheral ulcerative keratitis are to minimize inflammation, prevent superinfection, and promote healing of the ulcer.
Preservative free artificial tears, closure of puncta with plugs or cautery, and bandage soft contact lenes are used to treat associated dry eye and promote epithelialization of the ulcer.
Cyanoacrylate adhesive may be applied to the ulcer bed to limit ulceration in cases of impending perforation. This may also prevent influx of white blood cells from the tear film.
Topical antibiotics are used to prevent bacterial superinfection.
Systemic immunosuppression is often required to control ocular inflammation. Initial treatment initially is with steroids in the form of prednisone (1 mg/kg/day) or methylprednisolone (1 g/day x 3 days). Steroid sparing agents are indicated in the case of impending perforation, disease uncontrolled with steroids, or patients with associated rheumatoid arthritis as they are at increased risk for vascular events. Steroid sparing agents include antimetabolites such as methotrexate, azathioprine, or mycophenolate mofetil, T cell inhibitors such as cyclosporine or tacrolimus, alkylating agents such as cyclospophosphamide and chlorambucil, and biologic agents such as infliximab and rituximab.
Medical follow up
Medications and dosages are adjusted based on the level of clinical response. Systemic medications may be managed in collaboration with a Rheumatologist or other medical specialist.
Indications for surgical intervention include corneal perforation or excessive corneal thinning with impending perforation. Surgical options include lamellar, penetrating or crescentric keratoplasty, as well as possible corneo-scleral keratoplasty with a partial thickness scleral resection in cases of sceral melting.
Resection of the conjunctiva adjacent to the area of peripheral ulcerative keratitis may also be performed to limit inflammation originating from the conjunctiva.
Surgical follow up
Close follow up after surgical intervention is necessary. Patients should be monitored for recurrence of disease as well as infection or rejection of the graft.
Complications include infection and perforation of the ulcer.
Visual prognosis is related to the severity of disease. Patients with associated systemic disease have an increased mortality rate from vascular events.
http://www.aao.org/ ( American Academy of Ophthalmology)
Mortality rate in rheumatoid arthritis patients developing necrotizing scleritis or peripheral ulcerative keratitis. Effects of systemic immunosuppression. Foster CS, Forstot SL, Wilson LA. Ophthalmology. 1984 Oct;91(10):1253-63.
Twenty-five-year panorama of corneal immunology: emerging concepts in the immunopathogenesis of microbial keratitis, peripheral ulcerative keratitis, and corneal transplant rejection. Dana MR, Qian Y, Hamrah P. Cornea. 2000 Sep;19(5):625-43
The taming of the shrew? The immunology of corneal transplantation. Plever U, Schlickeiser S. Acta Ophthalmol. 2009 Aug;87(5):488-97.
A rare case of peripheral ulcerative keratitis in temporal arteritis. Papathanassiou M, Elezoglu A, Nikita E, Theodossiadis PG, Vergados I. Eur J Ophthalmol. 2009 Sep – Oct;19(5):866-9.
Visual outcome and corneal topography after eccentric "shaped" corneal grafts. Parmar P, Salman A, Jesudasan CA. Cornea. 2009 May;28(4):379-84.