Dear Editor,
Although wasp stings are common environmental injuries, those regarding the eye are
rare. Symptoms vary from mild hyperemia to sight-threatening complications [1
2
3
4]. Wasp stings to the eye lead to a mechanical insult caused by stinger penetration,
resultant toxicity, and an immune response [1]. A few reports have documented ocular
inflammation induced by the venom or a retained stinger. In most cases, intraocular
inflammation is treated with steroids or by removal of the stinger [2
3]. However, we encountered a case of severe panuveitis after an ocular wasp sting
which could not be controlled by conventional therapy, resulting in sympathetic ophthalmia
(SO) of the fellow eye. To our knowledge, this is the first report of SO induced by
wasp venom.
A 53-year-old man was stung in his right eye, and one day later, arrived at Kyungpook
National University Hospital with complaints of visual disturbance. The best-corrected
visual acuity (BCVA) was hand motion and intraocular pressure (IOP) was 34 mmHg. We
observed conjunctival injection, marked corneal edema with folds in Descemet's membrane,
epithelial defects, stromal opacity, and severe anterior chamber reaction. Corneal
and perilimbal infiltration was noted between 8 and 10 o'clock (Fig. 1A). The wasp
stinger could not be identified during slit-lamp examination. The lens and fundus
were obscured by corneal edema and anterior chamber reaction. B-scan ultrasonography
showed hyperechoic signals in the vitreous. The patient was diagnosed with panuveitis,
keratitis, and secondary glaucoma, and conservative treatment was initiated with moxifloxacin
ophthalmic solution 0.5%, prednisolone acetate 1%, atropine sulfate 1%, fixed-combination
dorzolamide/timolol, sodium hyaluronate 0.1% eye drops, oral prednisolone, and an
antihistamine. The following day, the corneal edema had reduced, but keratic precipitates
were observed (Fig. 1B). After one week, BCVA deteriorated to no light perception.
Two months later, BCVA and IOP of the affected eye were not changed, but corneal stromal
infiltration had remarkably worsened (Fig. 1C), and the patient complained of visual
disturbance with conjunctival injection in the fellow eye, despite a visual acuity
of the fellow eye was 20 / 20. However, IOP was 32 mmHg, and slit-lamp examination
revealed keratic precipitates, with mild inflammatory reactions in the anterior chamber
and vitreous (Fig. 1D). Fundus examination showed multiple small whitish-yellow infiltrations
at the posterior pole and mid-peripheral retina (Fig. 1E). Fluorescein angiography
showed multiple hyperfluorescent dots, which were assumed to be Dalen-Fuchs nodules
(Fig. 1F). Because there was no history of trauma or uveitis in the fellow eye, the
patient's left eye was diagnosed as SO. Ten days later, enucleation of the right eye
was performed because of severe ocular pain. The histopathological study found severe
fibrinous membrane in the anterior chamber, inflammatory cellular infiltration in
the ciliary body, and a severely disorganized retina in the enucleated eye (Fig. 1G).
Many inflammatory cells, including lymphocytes, plasma cells, eosinophils, and pigmented
melanocytes had infiltrated the choroid and retina, which suggested severe granulomatous
inflammation (Fig. 1H). With systemic steroid treatment and immunosuppression with
cyclosporine, inflammation of the left eye was well controlled.
Wasp stings are often associated with ocular inflammation. This is induced by a retained
stinger or the inoculation of venom. The clinical manifestations commonly involve
the cornea and anterior chamber [2
4]. However, wasp venom can invade the posterior segment and panuveitis can result
from the accumulation of toxins in the vitreous [3]. In our case, despite the absence
of a wasp stinger in careful ophthalmic examinations, ocular inflammation was severely
aggravated. Thus, direct inoculation to the vitreous or deep penetration of the venom
is a likely explanation. Furthermore, the patient suffered ocular inflammation in
the fellow eye. This supports the notion that wasp venom can trigger severe inflammation
with destruction of the eye structure and sensitize the fellow eye. Diagnosis of SO
is based on the history and clinicopathologic findings. Dalen-Fuchs nodules, whitish-yellow
lesions, are found typically at the choroid in the peripheral fundus of SO patients.
In our case, multiple whitish-yellow infiltrations were found in the fundus, which
were hyperfluorescent on fluorescein angiography.
Careful treatment of ocular wasp sting should proceed according to the mechanism of
injury and the clinical manifestations. Nakatani et al. [3] reported that panuveitis
after an ocular bee sting could be treated successfully through vitrectomy. In this
case, we could not perform vitrectomy because corneal opacity and a severe anterior
chamber reaction obscured the surgical field. Early and aggressive treatment, including
surgical treatment, can be helpful to ensure functional and anatomical recovery.