Rhegmatogenous retinal detachment following focal retinal necrosis in endogenous endophthalmitis due to methicillin-resistant Staphylococcus aureus septicemia

Abstract

Endogenous endophthalmitis leading to rhegmatogenous retinal detachment is one of the vision-threatening, devastating sequelae. Risk factors usually include a systemic focus of infection and conditions causing immunosuppression (diabetes, prostheses, and intravenous drug use). The most commonly implicated pathogens are Gram-positive coagulase-negative ones, especially Staphylococcus epidermidis. Cases of methicillin-resistant Staphylococcus aureus (MRSA) septicemia causing endogenous endophthalmitis have been reported with poor visual outcomes even with aggressive treatment. We hereby report a case of MRSA septicemia presenting with focal chorioretinal necrosis progressing to rhegmatogenous retinal detachment in a young postpartum female patient, which was successfully managed with vitrectomy.

Introduction

Endogenous endophthalmitis is a vision-threatening, serious intraocular infection caused by bacteria and fungi. It is caused by hematogenous spread of the organisms crossing blood ocular barrier. Endogenous endophthalmitis is seen in around 2%–8% of cases of all reported endophthalmitis cases, of which methicillin-resistant Staphylococcus aureus (MRSA) causing endogenous endophthalmitis is rare.[1] There are only a few reports in the literature highlighting vision-threatening sequelae such as retinal detachment in MRSA sepsis.[2,3,4] We report a case of endogenous endophthalmitis leading to focal chorioretinal necrosis and subsequent retinal detachment secondary to hospital-acquired MRSA septicemia in a young female in her early postpartum period.

Case Report

A female patient in her third decade had an uneventful vaginal delivery, following which a copper-T intrauterine device (IUD) was inserted as a contraceptive measure in the immediate postpartum period. Two weeks later, she presents with fever with chills, right-sided chest pain, and lower abdominal pain. She was suspected of having developed sepsis. Abdominal and uterine ultrasound confirmed the IUD to be in place with no migration. Prophylactically, copper-T was removed, following which blood culture was sent and was started on empirical antibiotics (metronidazole and piperacillin–tazobactam). Laboratory investigations revealed bicytopenia (anemia with thrombocytopenia) with neutrophilic leukocytosis. Chest X-ray showed right-sided pleural effusion. Computed tomography of the thorax and abdomen showed multiple septic emboli in bilateral lung fields, right-sided pleural effusion, hepatosplenomegaly, and mild ascites. Gynecology consultation ruled out uterine infection with a clean healing episiotomy wound.

Blood culture grew MRSA sensitive to vancomycin and linezolid and hence started on intravenous vancomycin accordingly. On day 3 of her hospital stay, she noticed diminution of vision in the right eye associated with redness and photophobia. On examination, her visual acuity was 20/60 in the right eye and 20/20 in the left eye. The right eye had anterior chamber cells corresponding to 2+, and fundus examination showed Grade 1 vitreous haze and a focal chorioretinitis lesion measuring approximately 1 disc diameter inferonasal to the disc. Hence, a final diagnosis of endogenous endophthalmitis secondary to hospital-acquired MRSA sepsis was made. She was continued on intravenous vancomycin and supplemented with topical dexamethasone 0.1% and moxifloxacin 0.5% combination along with homatropine 2% eye drops. Two days later, the vitreous haze had reduced. However, the focal chorioretinitis lesion had progressed into a full-thickness retinal break with a localized rhegmatogenous retinal detachment with subretinal exudates in the area of detachment [Figure 1a]. Optical coherence tomography through the focal lesion confirmed the presence of a full-thickness retinal break with associated subretinal fluid [Figure 1b]. Considering the unstable systemic status and presence of a single posterior pole break with macula on, pneumatic retinopexy was attempted with 0.3CC of 100% perfluoropropane gas along with intravitreal vancomycin (1 mg/0.1 ml) with anterior chamber tap. On postoperative day 4, the vision dropped to 20/200 with fundus showing retinal detachment threatening the macula with subretinal exudates [Figure 1c]. Hence, the patient was taken up for pars plana vitrectomy with posterior vitreous detachment induction, subretinal fluid drainage, endolaser of the primary break, 14% perfluoropropane gas tamponade with repeat intravitreal ceftazidime, and vancomycin injection. At 4 weeks postoperative, vision improved to 20/40 with fundus showing attached retina with resolution of exudates and retained gas [Figure 1d]. Systemic condition gradually stabilized with intravenous vancomycin alone without the need for any other antibiotics.

Figure 1.

(a) Necrosis of the focal lesion leading to a full-thickness retinal break and a localized rhegmatogenous retinal detachment, along with dispersed intraretinal and subretinal exudates surrounding the lesion. (b) Spectral-domain optical coherence tomography through the focal lesion showing a full-thickness retinal break with associated subretinal fluid. (c) Progression of retinal detachment post pneumatic retinopexy. (d) Successful attachment of retina after pars plana vitrectomy with endolaser and perfluoropropane gas tamponade

Discussion

Endogenous endophthalmitis by MRSA is one of the rare ocular infections with poor visual outcomes. It is most commonly seen in hospitalized and immunocompromised patients.[5] Certain conditions predisposing to MRSA sepsis include systemic steroid therapy, diabetes, lymphomas, localized infections such as pelvic and prostatic abscesses, and axillary, sternal, and leg infections.[6,7,8,9,10,11,12] It has also been reported in patients undergoing procedures such as hair transplantation.[13] Some characteristic but not unique features of MRSA endogenous endophthalmitis reported in the literature include higher rates of negative vitreous taps, aggressive course with higher chances of retinal detachment, and poor visual outcomes.[2,4,13]

A higher incidence of retinal detachment is reported in MRSA-related endogenous endophthalmitis, with rates reaching more than 50% in the reported case series.[2,3] Such higher rates are mostly due to the very high virulence of the organism, which causes rapid necrosis of the overlying retina. Ho et al. reported retinal detachment in six cases of MRSA endogenous endophthalmitis. They reported that the chances of retinal detachment increase if there is a delay in presentation for more than 2 weeks from the onset of symptoms. Our patient presented late due to the focal lesion away from the macula and the presence of low-grade vitritis, which made it asymptomatic for quite some time.

Management of MRSA-related endophthalmitis is quite challenging. Like any other endogenous endophthalmitis, systemic antibiotics remain the mainstay of treatment. The mainstay of treatment is systemic vancomycin. In resistant cases, antibiotics such as daptomycin, linezolid, tigecycline, and fifth-generation cephalosporins such as ceftaroline can be considered. Combination therapy with beta-lactams has also been shown to be efficacious in MRSA.[14] Ocular treatment depends on the severity of ocular involvement. In addition to systemic antibiotics, intravitreal antibiotics alone or pars plana vitrectomy combined with intravitreal antibiotics can be performed depending on the location and extent of chorioretinitis lesions, degree of vitritis, and the rapidity of progression. In our case, we opted for systemic antibiotics along with pneumoretinopexy and intravitreal antibiotics owing to a single posterior break with associated subretinal exudates, and the patient was just recovering from septicemia. However, pneumoretinopexy alone failed to reattach the retina, for which the patient had to be taken for vitrectomy. A primary vitrectomy with endolaser and internal tamponade would be better as a primary procedure for such patients.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Conflicts of interest

There are no conflicts of interest.

Funding Statement

Nil.