Figure 3-16 Facial characteristics of moderate acne rosacea. (Courtesy of James J. Reidy, MD.)
MANAGEMENT The ocular and systemic diseases are managed simultaneously, with systemic tetracyclines as the mainstay of therapy. Tetracyclines have anti-inflammatory properties that include suppression of leukocyte migration, reduced production of nitric oxide and reactive oxygen species, inhibition of matrix metalloproteinases (MMPs), and inhibition of phospholipase A2. In addition, tetracyclines may reduce irritative free fatty acids and diglycerides by suppressing bacterial lipases.
With time, oral therapy with doxycycline or minocycline can be tapered. In addition to oral therapy, application of topical metronidazole 0.75% gel, metronidazole 1% cream, or azelaic acid gel 15% to the affected facial areas can significantly reduce facial erythema. Azelaic acid gel 15% is the only gel approved by the US Food and Drug Administration for the treatment of papulopustular rosacea; it is thought to suppress rosacea through anti-inflammatory and antimicrobial mechanisms.
Ulcerative keratitis can be associated with infectious agents in rosacea, or it may have a sterile inflammatory etiology. Once it is ascertained that ulceration is noninfectious, topical corticosteroids, used judiciously, can play a significant role in reducing sterile inflammation and enhancing epithelialization of the cornea. In advanced cases with scarring and neovascularization, conservative therapy is generally recommended. Penetrating keratoplasty is a high-risk procedure in rosacea patients; it may result in a poor prognosis if the ocular surface is severely compromised.
Light-pulse treatment may help reduce eyelid erythema.
National Rosacea Society. Rosacea.org. [website]. Available at www.rosacea.org.
Schittek B, Paulmann M, Senyürek I, Steffen H. The role of antimicrobial peptides in human skin and in skin infectious diseases.
Infect Disord Drug Targets. 2008;8(3):135–143.
Seborrheic Blepharitis
CLINICAL PRESENTATION Seborrheic blepharitis may occur alone or in combination with staphylococcal blepharitis or MGD. Inflammation occurs primarily at the anterior eyelid margin; a variable amount of crusting, typically of an oily or greasy consistency, may be found on the eyelids, eyelashes, eyebrows, and scalp. Patients with seborrheic blepharitis often have increased meibomian gland secretions that appear turbid when expressed. Signs and symptoms include chronic eyelid redness, burning, and, occasionally, foreign-body sensation. A small percentage of patients (approximately 15%) develop an associated keratitis or conjunctivitis. The keratitis is characterized by punctate epithelial erosions distributed over the inferior one-third of the cornea. Approximately one-third of patients with seborrheic blepharitis have evaporative dry eye. See Table 3-9 for additional information.
Table 3-9
MANAGEMENT Eyelid hygiene is the primary treatment for seborrheic blepharitis as well as the associated MGD or staphylococcal blepharitis, as discussed elsewhere in this chapter. Concurrent treatment of the scalp disease with selenium sulfide shampoos is recommended.
Staphylococcal Blepharitis
PATHOGENESIS In general, the term staphylococcal blepharitis (caused usually by Staphylococcus aureus but occasionally by other species) refers to cases in which bacterial infection of the eyelids (and frequently the conjunctiva) is predominant. MGD and seborrheic blepharitis, in contrast, are primarily inflammatory. Clinical features that may help in the differential diagnosis of these conditions are summarized in Table 3-9.
CLINICAL PRESENTATION Staphylococcal blepharitis is seen more commonly in younger individuals. Symptoms include burning, itching, foreign-body sensation, and crusting, particularly upon awakening. Symptoms of irritation and burning tend to peak in the morning and improve as the day progresses, presumably as the crusted material that accumulates on the eyelid margin overnight is liberated.
Typical clinical manifestations include hard, brittle fibrinous scales and hard, matted crusts surrounding individual cilia on the anterior eyelid margin (Fig 3-17). Small ulcers of the anterior eyelid margin may be seen when the hard crusts are removed. Injection and telangiectasis of the anterior and posterior eyelid margins, white lashes (poliosis), lash loss (madarosis), and trichiasis may be seen in varying degrees, depending on the severity and duration of the blepharitis.
Figure 3-17 Staphylococcal blepharitis. Collarettes surround eyelashes. (Courtesy of Robert W. Weisenthal, MD.)
Staphylococcal blepharoconjunctivitis may present as a chronic (>4-week duration) unilateral or bilateral conjunctivitis. Clinical findings include a papillary reaction of the tarsal conjunctiva, particularly the inferior tarsal conjunctiva near the eyelid margin, as well as injection of the bulbar and tarsal conjunctivae. Conjunctival injection is mild and mucopurulent discharge scant. Concomitant ATD and/or lipid-induced tear-film instability may also occur.
Specific clinical signs in patients with chronic conjunctivitis may implicate certain bacterial species. S aureus is often associated with matted golden crusts and ulcers on the anterior eyelid margin, inferior punctate keratopathy, marginal corneal infiltrates, and, in rare cases, conjunctival or corneal phlyctenules. Moraxella lacunata may produce a chronic angular blepharoconjunctivitis, with crusting and ulceration of the skin in the lateral canthal angle and papillary or follicular reaction on the tarsal conjunctiva, sometimes with adjacent keratitis. Moraxella angular blepharoconjunctivitis is frequently associated with concomitant S aureus blepharoconjunctivitis.
Several forms of keratitis may develop in association with staphylococcal blepharoconjunctivitis. Punctate epithelial keratopathy manifests as erosions that stain with fluorescein; these erosions are often distributed across the inferior cornea, coinciding with the contour of the eyelids across the corneal surface. A diffuse pattern may also be observed, and asymmetric or unilateral keratopathy is not uncommon. The degree of corneal involvement can be markedly disproportionate to the severity of the eyelid disease, a circumstance that can lead to diagnostic confusion. Marginal corneal infiltrates may be the most distinctive clinical finding (Fig 3-18).
Figure 3-18 Staphyloccocal marginal corneal infiltrate. (Courtesy of David Rootman, MD.)
Phlyctenulosis is a local corneal and/or conjunctival inflammation that is believed to represent a cell-mediated, or delayed, hypersensitivity response induced by microbial antigens such as the cellwall components of staphylococcus. Phlyctenulosis is frequently associated with S aureus in developed countries and is classically associated with Mycobacterium tuberculosis in malnourished children in areas of the world with endemic tuberculosis.
Phlyctenules typically present unilaterally at or near the limbus, on the bulbar conjunctiva or cornea, as 1 or more small, rounded, elevated, gray or yellow, hyperemic, focal inflammatory nodules accompanied by a zone of engorged hyperemic vessels (Fig 3-19). They typically become necrotic and ulcerate centrally and then spontaneously involute over a period of 2–3 weeks. Conjunctival phlyctenules do not lead to scarring, but residual wedge-shaped fibrovascular corneal scars form along the limbus; when such scars are bilateral and inferior, they may suggest previous phlyctenulosis. Corneal involvement is recurrent, and centripetal migration of successive inflammatory lesions may eventually develop, affecting vision if untreated. Occasionally, such inflammation leads to corneal thinning and, in rare cases, perforation.
Figure 3-19 Confluent phlyctenules secondary to staphylococcal blepharitis.
LABORATORY EVALUATION Eyelid and conjunctival cultures can be performed in suspected cases of staphylococcal blepharoconjunctivitis when the initial diagnosis is in doubt, the treatment response is poor, or the infection is worsening. In cases of chronic unilateral conjunctivitis that is refractory to therapy, masquerade syndrome (conjunctival malignancy) and factitious illness should be ruled out.
The characteristic laboratory finding in staphylococcal blepharoconjunctivitis is a heavy, confluent growth of S aureus. Nevertheless, the finding of a light to moderate growth of bacteria