"Furry" Vision

Submitted by Enid Y. Sun, Matthew McCravy, Michelle Go and John, R. Stephens

Published October 6, 2019

A 44 year-old woman presented with 10 days of acute onset decreased vision, “floaters”, and bright flashes. She denied fevers, eye pain, or headache. She was referred for further evaluation after a retinal specialist noted bilateral optic nerve and macular edema. History revealed that she lived on a farm with a variety of animals including barn animals and cats. She denied recent animal scratches or bites.

On presentation, patient was afebrile and other vital signs were stable. Physical exam was unremarkable aside from significantly decreased visual acuity in her left eye as well as bilateral optic nerve edema (Figure, star), left worse than right. Other ocular findings included hemorrhage at left optic disc and cotton wool spots (Figure, arrow). She was also noted to have retinal exudates forming a partial macular star (Figure, circle). No lymphadenopathy was noted.

MRI brain with contrast, CSF analysis, ANA, dsDNA, rheumatoid factor, Lyme serologies, Rocky Mountain Spotted Fever serologies, HIV, and RPR were all negative. Bartonella IgM was positive at >1:20 and IgG positive at > 1:1024, supporting a diagnosis of Bartonella neuroretinitis. 

Question:

1. Which of the following statements is true about this condition?

1. Lymphadenopathy is common part of its presentation

2. Animal bite/scratch is necessary for its transmission

3. It is transmitted via the Ctenocephalides felis flea

4. Ocular damage is often permanent

   2.  What is the appropriate treatment for this condition?

1. Doxycycline & rifampin

2. Amoxicillin

3. Penicillin G

4. IVIG

Answers:

Question 1- Answer C.  It is transmitted via the Ctenocephalides felis flea1

Question 2.- Answer A.  Doxycycline & rifampin2

Take home points

• History of cat scratch or bite is not necessary for the transmission of Bartonella henselae.1

• Bartonella neuroretinitis is a complication of cat scratch disease characterized by optic nerve and subretinal edema.1

• A macular star may be seen on fundoscopic exam in some patients, but may not be evident until 1-2 weeks after transmission, if at all.1

• Clinically, Bartonella neuroretinitis presents as fever; malaise; and blurry vision, unilateral more common than bilateral. Lymphadenopathy is uncommon.2

• Treatment with rifampin and doxycycline may hasten recovery, but overall patients have good prognosis for visual recovery.2

• Ctenocephalides felis, the flea that is responsible for transmission of Bartonella henselae, can be found worldwide. It is an important vector in cat-to-cat transmission of B. henselae, but can also cause direct cat-to-human transmission.1

References

1. Cunningham ET & Koehler JE. Ocular bartonellosis.  Am J Ophthalmol 2000;130 (3) 340- 349

2. Reed JB, Scales DK, Wong MT, Lattuada CP Jr, Dolan MJ, & Schwab IR. Bartonella henselae neuroretinitis in cat scratch disease. Diagnosis, management, and sequelae. Ophthalmology. 1998;105(3):459 

Brief biographies

Drs. Enid Y. Sun and Matthew McCravy are both Internal Medicine residents at the University of North Carolina (UNC).

Dr. Michelle Go is an Ophthalmology resident at UNC.

Dr. John R. Stephens is a Professor of Internal Medicine and Pediatrics at UNC and Associate Program Director of UNC Hospital Medicine.