Septic metastatic endophthalmitis complicating Klebsiella pneumoniae scalp furuncle

Metastatic endophthalmitis presenting as subretinal abscess following a forearm furuncle

Metastatic endophthalmitis (ME) is rare form of secondary uveitis commonly prevalent in immunocompromised patients. A 55-year-old immunocompetent woman presented with painful decrease in left eye vision (referred to us as cytomegalovirus retinochoroiditis). Ocular examination revealed diffuse yellowish-white retinitis lesion (diagnosed as subretinal abscess on macular optical coherence tomography). Vitreous tap was unremarkable, but vitreous biopsy from the posterior vitreous overlying the subretinal abscess confirmed the growth of methicillin-sensitive Staphylococcus aureus (MSSA). Detailed systemic examination revealed a forearm furuncle, which yielded MSSA on culture. The infection followed relentless course despite aggressive treatment with pars plana vitrectomy and antibiotics (topical, systemic and intravitreal). This case is presented due to rarity of presentation of ME as subretinal abscess following skin infection, which became a management challenge. Due to its rapid progression and irreversible damage to ocular tissue, high index of suspicion and aggressive management is needed in such cases. The disease course, management and prognosis of such cases are dismal in majority of the patients.

The emergence of Klebsiella pneumoniae endogenous endophthalmitis in the USA: basic and clinical advances

Endogenous endophthalmitis (EE) is a rare but devastating infection that occurs secondary to seeding of the intraocular cavity from an extraocular focus. Recent reports suggest the increasing prevalence and incidence of Klebsiella pneumoniae as a causative organism in Asian countries. Analysis of the largest cohorts published to date suggests that K. pneumoniae endogenous endophthalmitis (KPEE) is 10 to 15 times more prevalent than other causes of EE. The incidence of KPEE among patients with systemic Klebsiella infection appears to be >100-fold more common than other causes of EE. The exact reason for these observations is not clear, but a number of studies now suggest that Klebsiella serotypes K1 and K2 have virulence factors that enhance their survival in diabetic patients and increase their pathogenicity. Here, we report two cases of KPEE in the USA. We also review the recent clinical and basic science literature on the prevalence, incidence, and pathophysiology of this emerging and devastating infection.