Assistant Program Director Tripler Army Medical Center, United States
Introduction: Hypervirulent Klebsiella pneumoniae (hvKp) is a community-acquired pathogen that often causes septic shock, bacteremia, liver abscesses, and endophthalmitis. Classically associated with the Pacific Rim, its incidence in the West is increasing. Here, presents an elderly patient with persistent hvKp bacteremia complicated by pyogenic liver abscesses and endophthalmitis.
Description: A 78-year-old Palauan with diabetes and chronic kidney disease presented with three days of abdominal pain, fevers, vomiting, and malaise. Physical exam was initially unrevealing. Labs showed mild neutrophilia of 8.01 x 103/uL, platelets 67 x 109 /L, AST/ALT 88/94 U/L, and procalcitonin 166.7 ng/mL. Urinalysis was notable for leukocyte-esterase. A presumptive diagnosis of pyelonephritis was made. She subsequently developed vasopressor dependent septic shock, and broad-spectrum antibiotics were promptly given. Blood cultures and urine cultures from admission grew pan-sensitive K. pneumoniae, and her antibiotics were changed to cefazolin. However, her abdomen showed multiple hepatic abscesses not amenable to drainage. On ICU day 5, she developed right eye conjunctival hemorrhage, and hypopyon prompting ophthalmologic assessment for endogenous endophthalmitis. Intravitreal vancomycin and ceftazidime were given, and ceftriaxone was increased to meningitic dosing. Her sepsis resolved and she transferred out of ICU on day 7. After 12 weeks of antibiotics with liver abscesses resolution she made a full recovering with the loss of her vision. Microbiologic assessment of her isolate showed a string test of 10mm. Molecular testing confirmed hvKp phenotype belonging to ST-2042 KL23. While not multi-drug resistant, it possessed a numerous plasmid-associated virulence factors, including those associated with endophthalmitis.
Discussion: Hypervirulent K. pneumoniae, like ST-2042 KL23, exhibit enhanced virulence factors leading to severe infections with high mortality, affecting both immunocompromised and healthy hosts. The incidence of hyKp is increasing and can clinically manifest in complex ways. This case demonstrates the many complications of hyKp infection, even in the absence of antimicrobial resistance, and re-informs the need for close attention to potential occult foci of infection for those with septic shock.
