Overview
- Definition
- Gram-negative , oxidase-negative aerobic bacilli that reside in human RBCs and endothelial cells
Multiple species exist, 8 of 21 are pathologic to humans
Bartonella henselae commonly associated with neuroretinitis, cat-scratch disease (CSD), Parinaud’s oculoglandular syndrome (POGS)
- Symptoms
Decreased vision, 20/25 to 20/200, may be worse
Floaters
Redness
Irritation
- Laterality
Mostly unilateral, can be bilateral and asymmetric
- Course
Onset of ocular symptoms 1 month after inoculation
Typically improves in 2–3 months with treatment
- Age of onset
Any age, more common in children and adolescents
- Gender/race
Occurs worldwide
- Systemic association
Cat-scratch disease
Parinaud’s oculoglandular syndrome
Exam: Ocular
Anterior Segment
- Follicular conjunctivitis
Conjunctival granuloma if primary site of inoculation
Anterior uveitis
+/− APD
Posterior Segment
Vitritis
- Neuroretinitis
Optic disc edema, significant
Macular star – radial lipid exudates, may be outside macula
May resolve in 8–12 weeks
- Focal or multifocal retinitis or choroiditis, mass
May be highly vascular and resemble bacillary angiomatosis
- Retinal vasculitis
Intraretinal hemorrhages and retinal ischemia
Vascular occlusion (BRAO or BRVO)
Serous macular detachment
Exam: Systemic
Transmission through cat scratch or bite or open wounds exposed to cat saliva or flea feces
- Systemic findings after inoculation
3–10 days – focal granuloma, small erythematous papule on skin at site of bite/scratch
7–14 days – conjunctival injection, chemosis, and water discharge
2–3 weeks – regional lymphadenopathy, malaise, myalgias, fatigue, low-grade fever (faded skin papule)
- Immunocompromised patients
May develop disseminated disease – endocarditis, meningitis, arthritis, osteomyelitis, pneumonia, hepatosplenomegaly
Imaging
OCT: macular thickening, intraretinal hyperreflective deposits, subretinal fluid, disc thickening
OCT-A: telangiectasias near disc
FA: early peripapillary telangiectasias with disc and vascular leakage; late disc leakage
Perimetry: cecocentral scotoma, paracentral scotoma, enlarged blind spot
VEP: reduced amplitude and increased latency in affected eye
Laboratory and Radiographic Testing
- Serologic testing, IgG, IgM
- Indirect fluorescent antibody (IFA)
88% sensitivity and 94% specificity
- Enzyme immunoassay (EIA) and Western blot
86–95% sensitivity and 96% specificity for IgG
Potential for cross-reactivity between species
PCR
Differential Diagnosis
Toxocariasis
Tuberculosis
Syphilis
Lyme disease
Sarcoidosis
Behcet disease
Rickettsiosis
Chikungunya
Systemic hypertension
Diabetic papillopathy
Anterior ION
Papilledema
Treatment
No consensus on treatment
May be observed in mild-to-moderate immunocompetent patient
- Doxycycline 100 mg BID PO × 10–14 days in >8 years old
May also give erythromycin, TMP-SMX, rifampin, or IM gentamycin
Severe infection – IV doxycycline and erythromycin with rifampin
Prednisone with antibiotics, 1 mg/kg/day with taper
Immunocompromised patients may require treatment up to 4 months
Conjunctival infections may be treated with combination drops and oral
Referral/Comanagement
Infectious disease specialist
Other consults depending on presenting systemic symptoms