Various initial presentations of community onsethypervirulent K2 serotype Klebsiella pneumoniae in healthy adult

Abstract

Correspondence to Jeong Rae Yoo, M.D. Tel: +82-64-717-2283 Fax: +82-64-717-1131 E-mail: [email protected] https://orcid.org/0000-00025488-7925 A previously healthy 43-year-old male patient was admitted to our hospital with a 3-day history of pain in the chest and the left scapular area. On admission, the patient was afebrile and had proteinuria. The serum creatinine level was 9.08 mg/dL (normal range, 0.9 to 1.3), and the C-reactive protein level was 27.86 mg/dL (normal range, 0.0 to 0.3). Chest computed tomography (CT) scan revealed multiple mixed groundglass attenuation nodules of various sizes and masses in both the lungs (Fig. 1A). Abdominal CT scan revealed an 1.7 cm sized enhancing lesion in the S5 region of the liver. Our initial diagnosis was hematogenous pulmonary and liver metastasis or vasculitis-associated glomerulonephritis. However, BacT/Alert blood culture after 5 days revealed the presence of Klebsiella pneumoniae of a hypermucoviscous phenotype, defined by a positive “string” test (Fig. 2). We confirmed a K2 serotype using 16S rRNA gene analysis. The antibiotic regimen was changed to intravenous amikacin and ciprofloxacin. After 1 week, the repeat chest CT scan revealed a marked increase in the extent of multiple necrotic cavitary masses and nodules in both the lungs along with liver abscesses (Fig. 1B). However, ophthalmological examination, brain magnetic resonance imaging, and transthoracic echocardiography, showed no abnormal findings. After 6 weeks, the chest CT scan revealed markedly reduced lesions in both the lungs (Fig. 1C). The antibiotic regimen was de-escalated to ciprofloxVarious initial presentations of community onsethypervirulent K2 serotype Klebsiella pneumoniae in healthy adult