In the latest Case Record of the Massachuestts General Hospital, a 32-year-old man was admitted to the hospital because of loss of vision. Ophthalmologic examination revealed painless conjunctival injection in both eyes, with purulent crusting and discharge on the lashes. A procedure and diagnostic tests were performed.
Infectious or noninfectious conjunctivitis can cause red eye. Other possible causes of red eye include blepharitis due to Staphylococcus aureus, ocular rosacea, keratitis, scleritis, and episcleritis. The absence of pain reduces the likelihood that eye disease is due to keratitis or scleritis, since patients with keratitis or scleritis present with pain.
• What is the differential diagnosis of corneal ulceration?
Tear fluid provides immunoactive substances, such as IgA, lysozyme, and lactoferrin, and nourishment of the cornea and protection from infection. A reduction in the amount of tear fluid or a lack of fluid puts the cornea at risk for infection and ulceration. Bacteria, fungi, viruses, and amoeba can infect the cornea. S. aureus, Streptococcus pneumoniae, and Moraxella liquefaciens are all possible causes of corneal infection. Patients with herpes simplex virus (HSV), the most common cause of corneal ulceration and corneal blindness in the United States, can present with painless corneal ulcers. Pseudomonas is associated with contact-lens use. Multiple organisms, including capnocytophaga, Candida albicans, and Strep. mitis, may also cause corneal ulcers in association with inhalational drug use. Immune-complex disease affects the periphery of the cornea, close to the limbal capillaries. Peripheral ulcerative keratitis and ulceration can be due to rheumatoid arthritis; the conditions are usually painless, but they occur in the later stages of disease. Other possible causes are systemic lupus erythematosus, scleroderma, and granulomatosis with polyangiitis (formerly known as Wegener’s).
• What are the manifestations of vitamin C deficiency?
Vitamin C deficiency, or scurvy, well recognized among seamen in the 18th century, is now a rare condition. Today, the risk factors for scurvy include alcoholism, low socioeconomic status, and psychiatric disorders that lead to poor nutrition. Symptoms include weakness, ecchymoses, bleeding gums, arthralgias, depression, and neuropathy. The physical examination may demonstrate corkscrew hairs, perifollicular erythema, hyperkeratosis, petechiae, and purpuric macules on the leg (pathognomonic for vitamin C deficiency).
Morning Report Questions
Q: What are the dermatologic and ocular manifestations of vitamin A deficiency?
A: Vitamin A deficiency causes night blindness, bilateral dry eyes, punctate keratitis, corneal neovascularization, and keratomalacia (corneal melting). In addition, vitamin A deficiency causes squamous metaplasia with general hyperkeratinization. When these lesions affect the eye, they appear as white spots, typically on the temporal aspect of the sclera, called Bitot’s spots. Follicular horny papules are also seen in vitamin A deficiency.
Q: What is the epidemiology of vitamin A deficiency in the United States?
A: Vitamin A deficiency is rare in the United States. The vitamin is found naturally in many foods, such as green leafy vegetables, carrots, sweet potatoes, tomatoes, cantaloupes, egg yolks, butter, cheese, and liver. Inadequate intake of vitamin A may be due to avoidance of these foods by patients with a psychiatric disorder or a selective diet. Malabsorption of fat-soluble vitamins may also cause vitamin A deficiency. Vitamin A storage lasts a relatively short time as compared with other vitamins such as vitamin B12. The presence of liver disease would further shorten this period of storage.