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Cryptogenic Liver Abscess Caused by a K1 Serotype Klebsiella pneumoniae Isolate
John J Psonis1, Yamil Michelen1, Kasturi Banerjee1
1Department of Medicine, Division of Infectious Diseases, Stony Brook University, Stony Brook, New York, USA.
Abstract:
Hypervirulent Klebsiella pneumoniae (hvKp) is a common cause of pyogenic liver abscesses in Asia but is quite uncommon in North America. Among the cases described in North America, only occasional reports have described molecular strain typing to confirm the K1 strain as the causative agent. We report a 56-year-old Hispanic female with no previous intra-abdominal pathology and no recent travel, who presented with subacute abdominal pain and developed bacteremia and monomicrobial pyogenic liver abscess due to a community-acquired K1 serotype K. pneumoniae isolate. In this case, the infection was recognized early, so the patient was successfully treated with percutaneous drainage and prolonged antibiotic therapy. Hvkp can cause severe invasive disease with high morbidity and mortality, and the recent emergence of multidrug resistance in these strains poses a serious threat to public health. In addition, the isolation of a K1 K. pneumoniae strain from a cryptogenic liver abscess in a Hispanic patient with no epidemiologic risk factors raises concern for a wider spread of the hypervirulent strain beyond Asian populations. Therefore, a high index of suspicion for hvKp infection in the Hispanic population can be crucial as the hypervirulent strain is likely to cause severe metastatic infection with significant morbidity and mortality.
Insights
Hypervirulent Klebsiella pneumoniae (hvKp) caused a liver abscess in a North American Hispanic patient, an uncommon occurrence. Early detection and treatment were successful, but this highlights the potential spread of this dangerous pathogen.
Area of Science:
- Infectious Diseases
- Microbiology
- Public Health
Background:
- Hypervirulent Klebsiella pneumoniae (hvKp) typically causes pyogenic liver abscesses in Asia.
- hvKp infections are rare in North America, with limited molecular confirmation of K1 strains.
Observation:
- A 56-year-old Hispanic female without risk factors presented with subacute abdominal pain.
- She developed bacteremia and a monomicrobial pyogenic liver abscess due to a community-acquired K1 serotype K. pneumoniae.
Findings:
- The patient received successful treatment via percutaneous drainage and prolonged antibiotics due to early recognition.
- Molecular strain typing confirmed the K1 serotype as the causative agent.
Implications:
- The emergence of multidrug-resistant hvKp strains poses a significant public health threat.
- Isolation of K1 hvKp in a Hispanic patient without risk factors suggests wider dissemination beyond Asian populations.
- A high index of suspicion for hvKp is crucial in Hispanic populations due to the potential for severe, invasive disease.
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