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Bartonella species infections are implicated in symptoms related to the structural, vascular (blood vessels), and neurological aspects of the eye. Here we present recent cases in which the latest eye imaging technology was used to confirm infection and explain why these findings are important for improving diagnosis of bartonellosis in individuals with symptomatic and asymptomatic infection.
Imaging Cat Scratch Disease (B henselae infection)
Medical textbooks generally describe cat scratch disease (CSD) as a classical triad of symptoms: fever, lymphadenopathy (swollen lymph nodes), and a lesion at the site of inoculation (bite or scratch). Although this may be true for a segment of the patient population, there are others who experience ocular (eye) symptoms without the classic presentation. What do these eye symptoms look like?
Neuroretinitis with stellate exudates (radiating pattern of infectious pus or fluid) is one historically recognized lesion found on the eye associated with cat scratch disease. The New England Journal of Medicine recently published an image of Bartonella neuroretinitis. In the image, the stellate exudates extruded into the eye to form an incongruously beautiful yellow starburst pattern.
More sensitive and sophisticated imaging technology, diagnostic testing, and test strategies are expanding the ocular findings associated with cat scratch disease. For example, the Survey of Ophthalmology recently published a case of CSD neuroretinitis that included optic nerve and optic nerve sheath enhancement seen on an MRI. The authors state that as far as they know this is the first reported case with these MRI findings.
Research and medical education based on cutting-edge imaging findings associated with bartonellosis have been published, including:
- Bartonella henselae infection associated with neuroretinitis, central retinal artery and vein occlusion, neovascular glaucoma, and severe vision loss (American Journal of Ophthalmology 2004)
- Bartonella and intraocular inflammation: a series of cases and review of literature (Clinical Ophthalmology 2011)
- Retinal artery occlusion due to Bartonella henselae infection: a case series (Acta Ophthalmologica 2016)
- Menagerie: Bartonella henselae chorioretinitis in the setting of diverse animal exposure (The Medical Journal of Australia 2018)
- Isolated conjunctival granuloma as a first manifestation of Parinaud’s oculoglandular syndrome: A case report (American Journal of Ophthalmology Case Reports 2019)
Use of Advanced Imaging
One thing these new imaging reports have in common is that they are typically associated with acute infections of Bartonella, like cat scratch disease (B. henselae). Meanwhile, patients with chronic bartonellosis who present with non-specific symptoms are unlikely to receive the benefits of these advanced imaging tests. It important for patients and providers to be aware of the complexity of multi-system disease. Symptoms in one body system may explain symptoms in another part of the body.
The ocular presentations of bartonellosis documented in these studies also speak directly to the prevalence of otherwise asymptomatic infection. We don’t really know how common asymptomatic infection with Bartonella species is, but findings from the fields of ophthalmology and transfusion medicine (blood donors) suggest that asymptomatic infection may be more common than is currently appreciated. A recent study published in PLoS Neglected Tropical Diseases reported that 3.5% of 500 asymptomatic blood donors in Brazil had detectable Bartonella species DNA in their blood. Comparable studies have not yet been conducted in the United States or other countries.
References
Pitassi, L. H. U. et al. (2015). Bartonella spp. bacteremia in blood donors from Campinas, Brazil. PLoS Neglected Tropical Diseases, 9(1), e0003467. 10.1371/journal.pntd.0003467 https://pubmed.ncbi.nlm.nih.gov/25590435/
Gray, A. V. et al. (2004). Bartonella henselae infection associated with neuroretinitis, central retinal artery and vein occlusion, neovascular glaucoma, and severe vision loss. American Journal of Ophthalmology, 137(1), 187-189. Thhps://doi.org/10.1016/S0002-9394(03)00784-0 https://www.ajo.com/article/S0002-9394(03)00784-0/fulltext
Nonaka, F. et al. (2018). Menagerie: Bartonella henselae chorioretinitis in the setting of diverse animal exposure. Medical Journal of Australia, 209(9), 284-286. https://doi.org/10.5694/mja18.00205 https://onlinelibrary.wiley.com/doi/abs/10.5694/mja18.00205
Kalogeropoulos, C. et al. (2011). Bartonella and intraocular inflammation: A series of cases and review of literature. Clinical Ophthalmology, 5, 817-829. 10.2147/OPTH.S20157 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3130920/
Domínguez, I. et al. (2019). Isolated conjunctival granuloma as a first manifestation of Parinaud’s oculoglandular syndrome: A case report. American Journal of Ophthalmology Case Reports, 14, 58-60. 10.1016/j.ajoc.2019.02.007 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6402948/
Niederer, R. L., & Al-Ani, H. H. (2021). Bartonella neuroretinitis. New England Journal of Medicine, 384, 952. 10.1056/NEJMicm2005549 https://www.nejm.org/doi/full/10.1056/NEJMicm2005549
Shen, J. et al. (2021). Clinical challenge – Scratching the surface of the sheath. Survey of Ophthalmology, 18, S0039-6257(21)00056-4. 10.1016/j.survophthal.2021.02.004 https://pubmed.ncbi.nlm.nih.gov/33610587/
Eiger-Moscovich, M. et al. (2016). Retinal artery occlusion due to Bartonella henselae infection: A case series. Acta Ophthalmologica, 94(5), e367-370. https://doi.org/10.1111/aos.12932 https://onlinelibrary.wiley.com/doi/full/10.1111/aos.12932
Neto, A. O. L. et al. (2021). Conjunctival and bulbar sporotrichosis as Parinaud’s oculoglandular syndrome acquired by blood inoculation. GMS Ophthalmology Cases, 11, Doc02. 10.3205/oc000175 https://pubmed.ncbi.nlm.nih.gov/33654649/
