Cat-scratch disease - External and Internal Eye
Dermatologic involvement is seen in approximately two-thirds of patients and includes evidence of a scratch without or with a papulopustular lesion, a widespread morbilliform eruption, erythema nodosum (warm, erythematous, and painful nodules in lower extremities), erythema multiforme, and/or thrombocytopenic purpura. Splenomegaly, weight loss, and parotid swelling rarely appear.
In two-thirds of patients, the lesion lasts for less than a month, although it may persist for 2 months or more in some cases. Nodes are tender, gradually increase in size, become erythematous and fluctuant, and may become suppurative. Most patients recover without sequelae. Encephalitis may occur in 1%-7% of cases, typically appearing 2-6 weeks after classic cat-scratch disease. Patients may present with associated seizures or status epilepticus.
The eye is involved in less than 10% of cases. Presentation is typically unilateral with either granulomatous conjunctivitis ("pink eye"), eyelid lesions (papules, pustules), or decreased vision from posterior ocular involvement.
The two most common ocular syndromes include oculoglandular syndrome of Parinaud (OSP) and neuroretinitis. OSP includes lymphadenopathy and a follicular conjunctivitis. Neuroretinitis includes inflammation of the optic nerve and macula.
A28.1 – Cat-scratch disease
79974007 – Cat scratch disease
Differential Diagnosis & Pitfalls
- Cutaneous tuberculosis or atypical mycobacterial infection (eg, Mycobacterium marinum)
- Granulomatosis with polyangiitis
- Foreign body granuloma
- Bacillary angiomatosis
- Hodgkin lymphoma
Differential diagnosis for neuroretinitis: