Conjunctivitis is a common condition and easy enough to treat, but several uncommon conjunctivitis syndromes require more care and should not be missed.
Conjunctivitis is either infectious (viral or bacterial) or noninfectious (allergic or nonallergic). Viral infections are more common in adults, bacterial ones in children, usually caused by Staphylococcus aureus, Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis. Adults tend to have more S. aureus infections, while the other pathogens are more common in children. An adenovirus is typically responsible for viral-associated infections in conjunctivitis.
Acute Hemorrhagic Conjunctivitis
Acute hemorrhagic conjunctivitis is rare but highly contagious and often presents as an epidemic; it occurs much more commonly in developing countries. It was first described in Ghana in 1969. Its prevalence in the United States is lower than that in developing countries, but epidemics have been reported in the Southwest. When contrasted with adenoviral conjunctivitis or herpes simplex keratitis, acute hemorrhagic conjunctivitis is comparatively rare. It affects any age, race, or gender, but appears to have a predilection for adolescents between 11 and 15.
The viruses most commonly responsible for hemorrhagic conjunctivitis are members of the Picornaviridae family, most commonly the coxsackievirus group A24 (CA24) and enterovirus E70 (EV70) strains. The associated conjunctivitis is characterized by the rapid onset of a severely painful infection that quickly develops a dramatic subconjunctival hemorrhage.
The signs and symptoms of acute hemorrhagic conjunctivitis begin after 12-48 hours of incubation and include sudden onset of ocular pain, eyelid swelling, foreign body sensation, excessive tearing, eye discharge, and photophobia. Pinpoint epithelial keratitis is also sometimes described. Depending on the stage at which the patient presents, findings may include swollen lids, conjunctival follicles, chemosis, and subconjunctival hemorrhages. These hemorrhages range from petechiae to large areas of conjunctival involvement.
Despite its dramatic appearance and associated pain, acute hemorrhagic conjunctivitis is usually benign and resolves in five to seven days. A polio-like condition, however, has been reported in approximately one in 10,000 patients infected with enterovirus 70 infections. These patients are extremely contagious, and the virus is transmitted directly from person to person by fingers and fomites. EPs should use proper disinfection techniques, and patients should be warned about the potential for spreading their infection. Palliative therapy with cool compresses and ophthalmic lubricants as well as pain control measures are the available treatment options.
An article titled "Conjunctivitis-Otitis Syndrome" described this syndrome for the first time. (Pediatrics 1982;69:695; http://bit.ly/2UpwzIo.) It noted an association between purulent bacterial conjunctivitis, otitis media, and highly resistant, nontypeable H. influenzae. Crusted eyes frequently mean a child also has an ear infection about 75 percent of the time.
Later, I became convinced that sinusitis was also commonly associated. The original discussion of this syndrome acknowledged that "the illness started with low-grade to moderate fever, mucopurulent rhinorrhea, and cough." (Pediatrics 1982;69:695; http://bit.ly/2UpwzIo.) Patients presenting with this syndrome often had a mucopurulent drainage for a week or longer. The importance of recognizing this syndrome is that it directs your treatment for the nontypeable Haemophilus influenzae. Treatment is amoxicillin-clavulanate and an appropriate ophthalmic antibiotic like trimethoprim/polymyxin (Polytrim). Others would, however, recommend no topical ophthalmic antibiotics if treating systemically.
Parinaud Oculoglandular Syndrome
Two to eight percent of patients with cat scratch disease present with parinaud oculoglandular syndrome, an atypical form of cat scratch disease characterized by tender regional lymphadenopathy of the preauricular, submandibular, or cervical lymph nodes associated with infection of the conjunctiva, eyelid, or adjacent skin surface. The conjunctivitis causes a unilateral red eye, foreign body sensation, and excessive watering of the eyes, and is described as granulomatous.
The infecting bacterium, Bartonella henselae, a small, fastidious, gram-negative bacillus, is the most common cause of this condition, but it is also seen with rodent-associated infections (tularemia or rabbit fever) by the bacterium Francisella tularensis. Sporotrichosis, caused by infections with Sporothrix schenckii, a dimorphic fungus existing in the mycelial and yeast phase, is another less common cause of parinaud oculoglandular syndrome and is seen more commonly in tropical and subtropical areas such as Brazil and Peru.
Even rarer diseases, tuberculosis, coccidioidomycosis, and syphilis, are associated with parinaud oculoglandular syndrome. Treating it when associated with cat scratch disease is different from that recommended for simple lymphadenopathy. The preferred regimen for any patient over age 8 is a combination of rifampin and doxycycline. For children under 8, the recommended treatment is rifampin plus azithromycin or rifampin plus trimethoprim-sulfamethoxazole.
Conjunctivitis is a relatively simple and routine pediatric diagnosis until it isn't. Acute hemorrhagic conjunctivitis, conjunctivitis-otitis syndrome, and parinaud oculoglandular syndrome are three conditions where pediatric conjunctivitis is not a simple diagnosis, and if missed, can have important clinical implications.
Watch this video of a patient with acute hemorrhagic conjunctivitis, a rare but highly contagious conjunctivitis.
This video shows a young boy with a purulent bacterial conjunctivitis, otitis media, and highly resistant, nontypeable H. Influenzae.
Watch this video of a boy with neck and facial swelling as well as conjunctivitis, symptoms of cat scratch disease presenting with parinaud oculoglandular syndrome.