Fatal disseminated pyogenic infection due to hypermucoviscous hypervirulent Klebsiella pneumoniae: A case report and literature review

Severe disseminated infection by hypermucoviscous Klebsiella pneumoniae successfully treated by intensive therapy with continuous hemodiafiltration using AN69ST: A case report and review of the literature

Klebsiella pneumoniae (Kpn) is one of the most common gram-negative bacilli causing lung, urinary tract, and biliary tract infections. However, as a distinct entity from classic Kpn, hypervirulent Kpn causing liver abscess, endophthalmitis, and lung abscess with poor prognoses has been reported mainly in East and Southeast Asia since the mid-1980s. Although the definition of hypervirulent Kpn is unclear, the hypermucoviscosity of Kpn is considered an important feature of hypervirulence. We present a case of emphysematous pyelonephritis accompanied by septic shock and acute kidney injury caused by hypermucoviscous Kpn infection that was successfully treated by intensive treatment. A 70-year-old woman with type 2 diabetes mellitus was diagnosed with emphysematous pyelonephritis, and string test-positive Kpn was detected in blood and urine cultures and percutaneous catheter drainage fluid from the renal pelvis. The patient was treated with intensive therapies including antibiotics, ventilator management, and continuous hemodiafiltration (CHDF) using AN69ST, which can absorb cytokines. During the course of treatment, the infection was complicated by pyogenic spondylitis, which was cured by antimicrobial therapy, and the patient was transferred to another hospital for rehabilitation on day 119 after admission. Hypermucoviscous Kpn infection often has a severe course, and it is important to initiate multidisciplinary treatment at an early stage, including rifampicin, which is expected to inhibit the viscosity of hypermucoviscous Kpn. In the current case, immediate CHDF using AN69ST was also considered a life-saving treatment because it improved both volume overload and neutrophil-activated hypercytokinemia.

Liver Abscess Combined with Endogenous Endophthalmitis Caused by Genotype ST25 Serotype K2 Hypervirulent Klebsiella pneumoniae: A Case Report

At present, invasive syndrome caused by hypervirulent Klebsiella pneumoniae (HvKp) is a widespread concern, and HvKp strains of different genotypes have been isolated. Here, we report a case of community-acquired liver abscess and endogenous endophthalmitis caused by a genotype ST25 serotype K2 (ST25-K2) HvKp strain in China. A 51-year-old man with diabetes was transferred to our hospital from a local community hospital with persistent fever for > 20 days and blurred vision in his left eye. A detailed examination revealed a liver abscess, endogenous endophthalmitis, and pneumonia. Bacterial cultures of pus from the liver abscess and the vitreous abscess of the left eye yielded Klebsiella pneumoniae (Kp), which was sensitive to the recommended drugs. In addition to positive string tests, a genetic analysis showed that the strain belonged to sequence type 25 (ST25) and serotype K2, and carried already-reported virulence genes, including iucA, rmpA2, rmpA, aerobactin, and entB. The pathogenic agent isolated from this patient was identified as HvKp. The patient’s general condition improved after a combination of treatments, including antimicrobial therapy, abscess drainage, and nutritional support. Unfortunately, the patient lost the vision in his left eye and developed secondary glaucoma, resulting in inevitable enucleation. Sequence 25 serotype K2 HvKp strains have been previously associated with nosocomial infections, but none associated with community-acquired liver abscess combined with endogenous endophthalmitis has yet been reported. Clinicians must be alert to the possibility of genotype ST25-K2 HvKp infection in patients with community-acquired liver abscess combined with an invasive infection, such as ocular discomfort.

Successful treatment of acute respiratory distress syndrome caused by hypervirulent Klebsiella pneumoniae with extracorporeal membrane oxygenation and continuous renal replacement therapy: A case report and literature review

Hypervirulent Klebsiella pneumoniae (hvKP) causes invasive infections and leads to high morbidity and mortality rates. Here, we report the case of a Chinese man with diabetes mellitus who developed acute respiratory distress syndrome and septic shock due to hvKP belonging to the K1 strain. The patient was treated with venovenous extracorporeal membrane oxygenation and continuous renal replacement therapy, in combination with antibiotics and recovered well. Clinicians should be aware of fatal infections caused by hvKP and investigate the best treatment options for patients at various stages of infection.