Parinaud Oculoglandular Syndrome

History

In 1889, Henri Parinaud described two patients with unilateral nodular or ulcerative conjunctivitis associated with regional lymphadenopathy. All of Parinaud’s patients had contact with animals. In subsequent publications, the association of granulomatous conjunctivitis with regional lymphadenopathy became known as Parinaud oculoglandular syndrome.

While the underlying cause of the disease originally described by Parinaud is unknown, we now know that the combination of granulomatous conjunctivitis and preauricular or cervical adenopathy has multiple causes. Advances in laboratory techniques, such as polymerase chain reaction (PCR) and immunodiagnostics, helped clarify our current understanding of the causes of this syndrome. Table 41.1 shows an extended list of the known causes of Parinaud oculoglandular syndrome.

The most common bacterial cause of Parinaud oculoglandular syndrome, Bartonella henselae, is difficult to culture. Thus the association of cat-scratch disease (CSD) with Parinaud oculoglandular syndrome was suspected long before the infectious agent was identified and characterized. The CSD association, first reported by Pesme and Marchand in 1950, and further supported by Cassady and Culbertson in 1953, relied on skin tests that are now obsolete. In 1985, Wear and associates demonstrated the cat-scratch bacillus in conjunctival specimens ( Fig. 41.1A and B). In 1999, Grando and associates cultured B. henselae from a conjunctival specimen in Parinaud oculoglandular syndrome.

Directed Work-Up

The history and physical findings are helpful in guiding laboratory testing and treatment for Parinaud oculoglandular syndrome. Table 41.2 shows a recommended approach to work-up and treatment based on symptoms and findings. As noted, more severe disease or immunocompromise requires more aggressive testing and treatment.

Animal scratch, bite, or exposure is a prominent feature of the presentation in many cases of Parinaud oculoglandular syndrome. Cats, dogs, and their associated fleas are known carriers of B. henselae . Rabbits, prairie dogs, squirrels, and ticks can harbor tularemia. Some of the rarer causes of Parinaud oculoglandular syndrome are also associated with exposure to rodents, ticks, and fleas. ^, Other important medical history includes a sexual disease history, tuberculosis (TB) exposure, and history of agricultural employment or activity.

In addition to CSD, many of the other entities that cause Parinaud oculoglandular syndrome are difficult to culture. Laboratory testing therefore relies on serology detection of antibodies to the inciting organism. Immunofluorescent antibody (IFA) and enzyme-linked immunosorbent assay (ELISA) tests are available for B. henselae , Francisella tularensis , Coccidioides immitis , and Epstein-Barr virus, as well as some of the more uncommon organisms.

Though widely available, immunologic testing for B. henselae suffers from relatively poor sensitivity and specificity. Variable results in immunologic titers due to immunocompromise or slow antibody response can be mitigated by repeat testing. Over time, a fourfold rise in serum titers is diagnostic.

Some of the limitations of immunologic titer tests may be overcome as sensitive and specific PCR testing becomes available. PCR testing has proved useful for B. henselae , C. immitis , and F. tularensis . ^,

Additional serologic testing includes serum tests for syphilis, mumps virus, rickettsia, mononucleosis, and chlamydial strains involved in lymphogranuloma venereum. Interferon-γ release assays (IGRA) may be used in TB testing.

When culture is attempted, suitable media for the growth of fungus and Mycobacterium should be included. F. tularensis can be grown on cysteine-enriched medium. In addition to culture, conjunctival scrapings should be submitted for acid-fast, Gram, and fungal stains. In typical, uncomplicated CSD, routine culture is not helpful.

Biopsy of the conjunctival lesions will usually confirm the diagnosis of granulomatous conjunctivitis but must be differentiated from lymphoma. A Warthin–Starry, Steiner silver stain or Brown–Hopp stain will sometimes demonstrate gram-negative pleomorphic bacilli in biopsies from patients with CSD.