Klebsiella endocarditis: report of two cases and review

Double trouble: an unusual case of Klebsiella pneumoniae invasive syndrome with liver abscess, gallbladder empyema and infective endocarditis

BACKGROUND

Klebsiella pneumoniae invasive syndrome (KPIS) is characterized by primary pyogenic liver abscess associated with metastatic infections. Although rare, Klebsiella endocarditis carries a high mortality risk.

CASE PRESENTATION

A 60-year-old lady with type II diabetes mellitus presented with fever, malaise, right hypochondriac pain and vomiting for two weeks. Ultrasound abdomen revealed a collection within liver, and distended gallbladder with echogenic debris within. 3 days after ultrasound guided pigtail drainage of gallbladder empyema, newly presence murmur detected. Pus, urine, and blood cultures obtained were positive for Klebsiella pneumonia. Echocardiogram exhibited oscillating mass attached to anterior mitral valve leaflet. After 6 weeks of intravenous ceftriaxone, follow-up echocardiogram and ultrasound showed complete resolution of mitral valve vegetation, hepatic and gallbladder collection.

CONCLUSION

Concomitant extrahepatic infective endocarditis (IE) should raise concerns in daily practice for patients with Klebsiella pneumoniae liver abscesses, despite the rarity of Klebsiella endocarditis. In the absence of diagnostic suspicion, antibiotic treatment regimens may be shortened, and adverse effects from IE infection may ensue.

Case Report: “Methicillin-Resistant Staphylococcus aureus Endocarditis Overlying Calcified Mitral Annular Abscess Misdiagnosed as Klebsiella pneumoniae Endocarditis”

Infective endocarditis (IE) involving mitral annular calcification (MAC) is a rare disease, but is potentially lethal due to frequent serious periannular complications, and therefore requires early diagnosis and prompt treatment. However, either reaching the correct diagnosis or the detection of periannular complications, even with conventional transesophageal echocardiography (TEE), remains challenging because calcium deposition obscures clear visualization of the area around the MAC. We describe a unique case of methicillin-resistant Staphylococcus aureus (MRSA) IE involving a calcified mitral annular abscess, which was initially misdiagnosed as Klebsiella pneumoniae IE. Accurate diagnosis of MAC-related IE as well as detection of the annular abscess were made possible by 4D TEE, leading to successful cardiac surgery, which confirmed MRSA IE pathologically, and the associated annular abscess. This case highlights the usefulness of 4D TEE for the accurate diagnosis and proper surgical planning. In addition, this case raises the limitations of the modified Duke criteria in cases of definite IE with dual bacteremia.

Infective endocarditis secondary to Klebsiella pneumoniae-associated emphysematous cystitis

Klebsiella pneumoniae is responsible for about 1.5% of infective endocarditis (IE) cases. IE caused by community-acquired K. pneumoniae infection has rarely been reported. An 80-year-old man presented at our hospital with hypotension and hypoxaemia, and a history of aortic valve stenosis and no history of recent dental treatment. Transthoracic echocardiography at admission showed no signs of heart failure or vegetation. CT revealed typical signs of emphysematous cystitis (EC). The patient was treated for EC-associated septic shock. K. pneumoniae was detected in urine and blood cultures on day 3. Symptoms of heart failure developed on day 6 and clinical examination revealed a heart murmur. An identification of vegetation and perforation of the mitral valve on repeat echocardiography confirmed the diagnosis of IE secondary to K. pneumoniae infection. A surgical valve replacement was performed on day 7. Repeated point-of-care ultrasound played a role in the early diagnosis of IE.

Infective endocarditis by Klebsiella species: a systematic review

This study aimed to systematically analyze all cases of infective endocarditis (IE) by Klebsiella species in the literature. A systematic review of PubMed, Scopus and Cochrane library (through 27^th January 2021) for studies providing epidemiological, clinical, microbiological as well as treatment data and outcomes of IE by Klebsiella species was performed. In this review, a total of 66 studies were included, providing data for 67 patients. A prosthetic valve was present in 16.4%, while the most common causative pathogen was K. pneumoniae followed by K. oxytoca. The aortic valve was the most commonly infected intracardiac site, followed by the mitral valve. The diagnosis was based on transthoracic echocardiography in 46.2%, while the diagnosis was set at autopsy in 9.2% of included patients. Blood cultures were positive in 93.8%. Fever and sepsis were the most frequent clinical presentations, followed by embolic phenomena, paravalvular abscess, and heart failure. Cephalosporins, aminoglycosides, and carbapenems were the most frequently used antimicrobials. Surgical treatment along with antimicrobials was performed in 37.3% of included patients. Clinical cure was noted in 80.3%, while the overall mortality was 19.4%. Infection at the aortic valve was independently associated with mortality by IE. This systematic review gives a comprehensive description of IE by Klebsiella and provides information on epidemiology, clinical manifestations, therapeutic strategies and their outcomes.

A Case of Polymicrobial, Gram-Negative Pulmonic Valve Endocarditis

Infective endocarditis due to Gram-negative, non-HACEK bacteria is a rare clinical entity. Even moreso, isolated pulmonic valve endocarditis accounts for less than 1.5-2% of all cases of infective endocarditis. These disease pathologies commonly occur in the setting of intravenous drug abuse, indwelling catheters or cardiac devices, or underlying structural heart disease. We present a unique case of pulmonic valve endocarditis in the setting of persistent polymicrobial bacteremia with Klebsiella pneumoniae and Citrobacter koseri with recent gastrointestinal instrumentation evolving into isolated pulmonic valve endocarditis.

A case of Klebsiella oxytoca endocarditis in an intravenous drug user

Non-HACEK Gram-negative bacilli account for only a small percentage of infective endocarditis cases globally. Among those, Klebsiella species account for only about 10% of cases and are most often health-care acquired. We present a rare case of Klebsiella oxytoca endocarditis in a young intravenous drug user.

Allogeneic stem cell transplantation in a blast-phase chronic myeloid leukemia patient with carbapenem-resistant Klebsiella pneumoniae tricuspid valve endocarditis: A case report

In chronic myeloid leukemia (CML), the occurrence of blastic transformation is rare. Treatment outcome is generally poor. Allogeneic stem cell transplantation (allo-SCT) is the only potentially curative treatment option for advanced-phase CML. Infections caused by carbapenem-resistant Klebsiella pneumoniae (CRKP) isolates are associated with high morbidity and mortality rates, particularly in patients with haematological malignancies. Infection and colonization by these multiresistant bacteria may represent a challenge in SCT recipients for the management of post-transplantation complications, as well as for the eligibility to receive a transplant in patients who acquire the pathogen prior to the procedure. We herein report the case of a blast-phase CML patient with a highly resistant, CRKP-associated tricuspid valve endocarditis, who was treated with a combination of systemic antimicrobial therapy and surgical valve repair, and subsequently underwent a successful allo-SCT.

Infective endocarditis caused by Klebsiella oxytoca in an intravenous drug user with cancer

Infective endocarditis caused by Klebsiella species is rare, with most isolates being K. pneumoniae. We report the case of a 24-year-old intravenous drug user with newly diagnosed seminoma who developed K. oxytoca endocarditis. In addition to having K. oxytoca isolated from blood culture, cultures of that species were obtained from a retroperitoneal metastasis found on original presentation.

K2 serotype Klebsiella pneumoniae causing a liver abscess associated with infective endocarditis

Klebsiella pneumoniae primary liver abscess (KPLA) is an emerging disease that is associated with distant septic complications. We report the first case of KPLA associated with infective endocarditis. The K. pneumoniae strain was a hypermucoid K2 serotype carrying the rmpA virulence-associated gene.

Carbapenem-resistant Klebsiella pneumoniae endocarditis in a young adult. Successful treatment with gentamicin and colistin

INTRODUCTION

Enterobacteriaceae are rarely the etiologic agents of endocarditis, with Klebsiella species being especially rare. From the end of 2005, isolates of carbapenem-resistant Klebsiella pneumoniae began to appear in various hospitals across Israel, sensitive only to colistin and gentamicin. We present a case of hospital-acquired endocarditis caused by carbapenem-resistant K. pneumoniae in a young adult.

CASE REPORT

An 18-year-old man with 40% full thickness burns developed acute bacterial endocarditis complicated by embolic myocardial infarction. Carbapenem-resistant K. pneumoniae carrying the blaKPC3 gene was isolated from multiple blood cultures. He recovered fully after antibiotic treatment with colistin and gentamicin.

CONCLUSIONS

To our knowledge, this is the first reported case of acute bacterial endocarditis caused by carbapenem-resistant K. pneumoniae. The combination of intravenous colistin and gentamicin was effective and resulted in the cure of this patient's endocarditis without the need for surgical intervention.

Endocarditis caused by extended-spectrum-beta-lactamase-producing Klebsiella pneumoniae: emergence of resistance to ciprofloxacin and piperacillin-tazobactam during treatment despite initial susceptibility

Three episodes of bacteremia occurred in the course of prosthetic valve endocarditis caused by an extended-spectrum-beta-lactamase (ESBL)-producing Klebsiella pneumoniae strain. The second isolate developed resistance to ciprofloxacin and the third isolate to piperacillin-tazobactam (PIP-TZ) following sequential therapy with each agent. The first isolate was resistant to PIP-TZ only at high inocula, the second isolate acquired increased transcription of the acrA gene, and the third isolate became resistant to PIP-TZ due to loss of beta-lactamase inhibition by TZ. We question if and how PIP-TZ susceptibility should be reported for ESBL-producing Enterobacteriaceae.

Klebsiella Pneumoniae: A Rare Cause of Device-Associated Endocarditis

Intravascular infections involving implanted pacemakers and defibrillators are being seen with increasing frequency. This report describes a case of intravascular infection of an implanted defibrillator with Klebsiella pneumoniae, an unusual pathogen for pacemaker or defibrillator infection.

Endocarditis due to rare and fastidious bacteria

The etiologic diagnosis of infective endocarditis is easily made in the presence of continuous bacteremia with gram-positive cocci. However, the blood culture may contain a bacterium rarely associated with endocarditis, such as Lactobacillus spp., Klebsiella spp., or nontoxigenic Corynebacterium, Salmonella, Gemella, Campylobacter, Aeromonas, Yersinia, Nocardia, Pasteurella, Listeria, or Erysipelothrix spp., that requires further investigation to establish the relationship with endocarditis, or the blood culture may be uninformative despite a supportive clinical evaluation. In the latter case, the etiologic agents are either fastidious extracellular or intracellular bacteria. Fastidious extracellular bacteria such as Abiotrophia, HACEK group bacteria, Clostridium, Brucella, Legionella, Mycobacterium, and Bartonella spp. need supplemented media, prolonged incubation time, and special culture conditions. Intracellular bacteria such as Coxiella burnetii cannot be isolated routinely. The two most prevalent etiologic agents of culture-negative endocarditis are C. burnetti and Bartonella spp. Their diagnosis is usually carried out serologically. A systemic pathologic examination of excised heart valves including periodic acid-Schiff (PAS) staining and molecular methods has allowed the identification of Whipple's bacillus endocarditis. Pathologic examination of the valve using special staining, such as Warthin-Starry, Gimenez, and PAS, and broad-spectrum PCR should be performed systematically when no etiologic diagnosis is evident through routine laboratory evaluation.

Monotherapy versus combination therapy for bacterial infections

The authors discuss the latest findings regarding the use of one or more antimicrobial drugs for a variety of infections. They offer suggestions for treatment based on a host of considerations, including the synergy and antagonism of specific drugs, type of infection, potential toxicities, and cost.