A case of cat-scratch disease with unusual ophthalmic manifestations.

We report a case of cat-scratch disease with unusual posterior segment manifestations. A 12-year-old healthy male presented with three weeks history of decreased visual acuity in the right eye. A significant history of cat exposure and elevated Bartonella titers were present. A large white-gray vascularized mass extending off the optic disk, an early stellate maculopathy, a plaque of choroiditis, an inferior serous retinal detachment involving the macula were present in the right eye. Sector papillitis and a focal area of chorioretinitis along the superotemporal arcade with associated retinal artery to vein anastomosis were present in the left eye. Bilateral optic nerve head involvement including peripapillary angiomatosis, retinal-retinal anastomosis and plaque choroiditis as ocular complications of cat-scratch disease have not been previously described to our knowledge and make this case noteworthy.

INTRODUCTION

Cat-scratch disease is usually a self-limited infection of the pleomorphic Gram negative rod Bartonella henselae. At the time of primary infection, a macule, papule, or vesicle may form at the site of inoculation followed by tender regional lymphadenopathy and flue-like illness which resolves over a period of months.1 Rarely, hematogenous spread of the initial infection may result in ocular and neurological complications.2 This report describes an unusual case of cat-scratch disease presenting with a large optic nerve mass, bilateral optic nerve involvement, neuroretinitis, serous retinal detachment, choroiditis, and a retinal–retinal anastomosis with subjacent focal retinochoroiditis.

CASE REPORT

A twelve-year old healthy male presented with three weeks of decreased visual acuity in his right eye. This was preceded by a febrile illness with sore throat, headache and myalgias. Three days prior to presentation, he was treated with amoxicillin for presumed “strep tonsillitis” after a positive rapid strep-test. His past ocular and medical histories were unremarkable.

On examination, his best-corrected visual acuity (BCVA) was 4/200 in the right eye and 20/20 in the left. External examination was unremarkable. There was no evidence of lymphadenopathy. His pupils were reactive with a greater than 1.8 log units right afferent pupillary defect (APD). Slit-lamp exam was unremarkable except for rare cell in the anterior chamber and vitreous in both eyes. Automated visual field testing revealed a central scotoma with a dense superior arcuate defect in the right eye [Figure 1].

Figure 1

Humphrey automated visual field of the right eye demonstrating diffuse depression with dense superior arcuate scotoma

Dilated fundoscopic examination of the right eye revealed a large white-gray vascularized mass extending off the optic disk with significant overlying vitreous reaction. An early stellate maculopathy was also present. The choroid in the macular area had a yellow-white color without nodularity suggestive of a plaque of choroiditis [Figure 2a]. Moreover, a serous retinal detachment involving the macula and the inferior retina was present. The left optic disc had a very small indistinct sector of hyperemia at the inferior edge [Figure 2b] that was readily identified on fluorescein angiography (FA). Additionally, a focal area of chorioretinitis was present along the superotemporal arcade in the left eye [Figure 2c]. FA revealed early hyperfluorescence with late leakage of the optic disc mass of the right eye [Figure 2d]. Late leakage on FA also occurred in the inferior portion of the optic disc [Figure 2e] and the focal area of chorioretinitis [Figure 2f] of the left eye. The vascular component of the optic disc mass of the right eye was evident and the focal area of chorioretinitis in the left eye demonstrated a retinal artery to vein anastomosis [Figure 2f]. There was no evidence of vasculitis.

Figure 2

Fundus photograph of the right (a) and left (b, c) eyes with corresponding fluorescein angiography frames (d, early phase; e and f, mid phase) at presentation. Note the large inflammatory mass with a marked vascular component of the optic nerve head, the whitish discoloration of the macular choroid, and the serous macular detachment with early star formation in the right eye (a and d). The left eye has an inferior sector of papillitis (b and e) and a focal area of chorioretinitis along the superotemporal arcade (c) with associated retinal artery to vein anastomosis (arrow) (f)

Upon further questioning, the patient admitted to a significant history of cat exposure, including a kitten as a household pet, but denied being scratched. He was empirically treated with doxycycline 100 mg twice a day for the suspicion of cat-scratch disease, clindamycin 200 mg three times a day for the possibility of toxoplasmosis, and prednisone 40 mg a day, pending serology. Pediatric rheumatology consult was obtained. Ancillary laboratory tests including complete blood count, liver function tests, chest X-ray, angiotensin-converting enzyme, tuberculin skin test, RPR, urinanalysis, and antistreptolysin-O antibodies were within normal limits. Serologic studies for toxoplasmosis, toxocariasis, and lyme disease were negative. However, antibodies to Bartonella were elevated (IgM 1:128 and IgG 1:1024). Consequently, the clindamycin was discontinued.

Three weeks after presentation, BCVA improved to 20/200 in the right eye and 20/20 in the left; however, the APD persisted. At this visit, inflammation was reduced in both eyes and the right optic disc mass had decreased in size compared to initial presentation. At six weeks, BCVA was 20/80 and 20/20 with persistent right APD and arcuate field defect. The posterior segment lesions had significantly regressed and appeared involuted with marked reduction in leakage on FA [Figure 3]. The serous retinal detachment resolved with subretinal hard exudates and macular striae [Figure 3a]. Consequently, the doxycycline was discontinued, and the prednisone was slowly tapered without recurrence, 6 months after presentation.

Figure 3

Fundus photograph of the right (a) and left (b, c) eyes with corresponding fluorescein angiography frames (d, early phase; E and F, mid phase) 6 weeks after presentation. The large inflammatory mass of the right optic nerve head is now involuted (a and d) and the whitish discoloration of the macular choroid as well as the serous macular detachment have resolved with residual subretinal hard exudates (a). The left sector papillitis and focal area of chorioretinitis along the superotemporal arcade are inactive (b, c, e, f)

DISCUSSION

Ocular involvement of cat-scratch disease occurs in 5–10% of cases, and is the most common non-lymphatic organ involvement. It was first described by Henri Parinaud when he reported three patients with chronic fever, regional lymphadenopathy, and follicular conjunctivitis.3 This form of ocular involvement, known as Parinaud's oculoglandular syndrome, is the most common and occurs in 5% of cases. Neuroretinitis is seen in 1-2% of systemic cat scratch disease and is associated with a mild-to-moderate degree of inflammation, optic disc swelling, and delayed macular star formation.1 It is usually unilateral although bilateral involvement has been described.4 Although neuroretinitis is considered a “classic” manifestation of the disease, it was found to be the third most common posterior segment finding in a retrospective case series of 24 patients.5 The most common fundus feature was discreet white retinal or choroidal lesions occurring in 83% of eyes followed by optic disk swelling in 46% of eyes. Less common posterior segment manifestations included vascular occlusive events, serous retinal detachment, vitreous hemorrhage, intermediate uveitis and inflammatory lesions of the optic nerve head.15–7

The diagnosis of cat-scratch disease is based on symptomatology, exposure to cats, clinical findings and positive serology/cultures. All these criteria were fulfilled in the current case. Polymerase chain reaction (PCR) has been recently used to identify Bartonella species in ocular fluids from patients with neuroretinitis.89 However, PCR is reserved for cases where the diagnosis remains questionable or for research studies as serologic testing for Bartonella is highly sensitive and specific in immunocompetent patients.110

Cat-scratch disease is usually self limiting and treatment remains controversial. However, most experts recommend treatment with doxycycline 100 mg twice a day with or without rifampin 300 mg twice a day for four to six weeks particularly in cases with severe ocular complications or in immunocompromised patients. The role of corticosteroids is also controversial.111

The case reported here has 3 noteworthy findings. First, the bilaterality of optic nerve head involvement is unusual, although it has been reported previously in the setting of bilateral neuroretinitis12 and papillitis.511 To our knowledge, the occurrence of an inflammatory mass of the optic nerve head in one eye and sector papillitis in the other has not been previously described in English peer reviewed literature. The right optic nerve head mass is consistent with previous descriptions of peripapillary angiomatosis6 and inflammatory mass of the optic nerve head7 associated with ocular bartonellosis. The vascular component of the lesion was evident on FA. Another unique feature of this case is the retinal–retinal anastomosis observed in the left eye that was intimately associated with a focal chorioretinitis [Figure 2c and f]. Both the right angiomatous inflammatory lesion of the optic nerve head and the left retinal–retinal anastomosis could be explained by the stimulatory effect that the organism has on endothelial cell migration and proliferation.13 Lastly, the plaque of choroiditis noted in the macula of the right eye [Figure 2a] is also unusual. Although focal areas of choroiditis or retinitis are the most common posterior segment manifestations of the disease,5 diffuse plaque like choroiditis has not been previously described.

In summary, we describe an unusual case of cat-scratch disease with ocular involvement. Bilateral optic nerve head involvement including peripapillary angiomatosis, retinal–retinal anastomosis and plaque choroiditis make this case noteworthy.