Secondary orbital abscess from hypervirulent Klebsiella pneumoniae panophthalmitis with scleral necrosis

Hypervirulent Klebsiella pneumoniae (hvKp) is a gram-negative bacillus capable of causing fulminant visual and systemic outcomes in otherwise stable individuals. Classically, it is associated with liver abscesses and diabetes mellitus/immunosuppression in South-East Asians. In most cases, hvKp encompasses the hypermucoviscous Klebsiella pneumoniae (hmvKp) phenotype with excess capsular material on "string test," but these terms are not synonymous. Typically, hvKp manifests as endogenous endophthalmitis without true intraorbital pathology. We present a rare case of hmvKp-driven scleral necrosis creating orbital abscess and orbital compartment syndrome. A 73-year-old Chinese female presented with six days' worsening red, painful right eye with preceding one month of gastrointestinal symptoms on a background of unmedicated diabetes mellitus. Right visual acuity was light perception, with intraocular pressure of 36 mmHg. Examination revealed severe globally reduced ocular motility, 3 mm right axial proptosis, 360-degree chemosis, and shallow anterior chamber with dense fibrin. B-scan showed vitritis with a positive T-sign. Vitreous and blood cultures confirmed hmvKp. On abdominal computed tomography, she had hepatic and renal abscesses. She showed no visual improvement with intravitreal ceftazidime/vancomycin. On day six of admission, she suddenly developed orbital compartment syndrome. Further imaging showed an orbital abscess secondary to scleral melt and orbital extrusion of intraocular contents and pus. She underwent drainage and enucleation; preserving contralateral vision and life. This case exemplifies hmvKp with the defining clinical features of hvKp. To our knowledge, this is a unique case of scleral melt with these devastating corollaries.