Bilateral osteomyelitis and liver abscess caused by hypervirulent Klebsiella pneumoniae- a rare clinical manifestation (case report)

Hypervirulent and carbapenem-resistant Klebsiella pneumoniae: A global public health threat

The evolution of hypervirulent and carbapenem-resistant Klebsiella pneumoniae can be categorized into three main patterns: the evolution of KL1/KL2-hvKp strains into CR-hvKp, the evolution of carbapenem-resistant K. pneumoniae (CRKp) strains into hv-CRKp, and the acquisition of hybrid plasmids carrying carbapenem resistance and virulence genes by classical K. pneumoniae (cKp). These strains are characterized by multi-drug resistance, high virulence, and high infectivity. Currently, there are no effective methods for treating and surveillance this pathogen. In addition, the continuous horizontal transfer and clonal spread of these bacteria under the pressure of hospital antibiotics have led to the emergence of more drug-resistant strains. This review discusses the evolution and distribution characteristics of hypervirulent and carbapenem-resistant K. pneumoniae, the mechanisms of carbapenem resistance and hypervirulence, risk factors for susceptibility, infection syndromes, treatment regimens, real-time surveillance and preventive control measures. It also outlines the resistance mechanisms of antimicrobial drugs used to treat this pathogen, providing insights for developing new drugs, combination therapies, and a "One Health" approach. Narrowing the scope of surveillance but intensifying implementation efforts is a viable solution. Monitoring of strains can be focused primarily on hospitals and urban wastewater treatment plants.

Genotypic characterization of hypervirulent Klebsiella pneumoniae (hvKp) in a tertiary care Indian hospital

Hypervirulent Klebsiella pneumoniae (hvKp) is an emerging pathogen and causes endophthalmitis, liver abscess, osteomyelitis, meningitis, and necrotizing soft tissue infections in both immunodeficient and healthy people. The acquisition of the antibiotic resistance genes of hvKp has become an emerging concern throughout the globe. In this study, a total of 74 K. pneumoniae isolates were collected and identified by VITEK2 and blaSHV gene amplification. Out of these, 18.91% (14/74) isolates were identified as hvKp by both phenotypic string test and genotypic iucA PCR amplification. The antibiotic susceptibility revealed that 57.14% (8/14) isolates were multidrug-resistant (MDR) and 35.71% (5/14) isolates were extremely drug-resistant (XDR). All the isolates were resistant to β-lactam, β-lactamase + inhibitor groups of antibiotics, and the least resistance to colistin. Of 14 hvKp isolates, all isolates are positive for iroB (100%), followed by iutA (92.85%), peg344 (85.71%), rmpA (57.14%), and magA (21.42%) genes. Among serotypes, K1 was the most prevalent serotype 21.4% (3/14), followed by K5 14.3% (2/14). The most common carbapenemase gene was blaOXA-48 (78.57%) followed by blaNDM (14.28%) and blaKPC (14.28%) which co-carried multiple resistance genes such as blaSHV (100%), blaCTX-M (92.85%), and blaTEM (78.57%). About 92.85% (13/14) of hvKp isolates were strong biofilm producers, while one isolate (hvKp 10) was the only moderate biofilm producer. The (GTG)5-PCR molecular typing method revealed high diversity among the hvKp isolates in the tertiary care hospital. Our findings suggest that MDR-hvKp is an emerging pathogen and a challenge for clinical practice. In order to avoid hvKp strain outbreaks in hospital settings, robust infection control and effective surveillance should be implemented.

A mini case report: Klebsiella pneumoniae-induced metastatic neck abscess following laparoscopic appendectomy

Common complications following laparoscopic appendectomy include wound infection, bleeding, intra-abdominal abscess, small bowel obstruction, stump leakage, and stump appendicitis. Here, we presented a case reporting detailing a rare complication following laparoscopic appendectomy: the development of a metastatic neck abscess induced by Klebsiella pneumoniae(K. pneumoniae). A 49-year-old male underwent emergency laparoscopic surgery with prophylactic antibiotic administration for acute appendicitis. Subsequently, he experienced persistent neck pain and fever postoperatively, prompting further investigation. Pus and blood cultures revealed K. pneumoniae, with magnetic resonance imaging confirming the presence of a neck abscess. Antibiotic therapy was adjusted, and surgical drainage of the abscess was performed after multidisciplinary consultation. The patient was discharged without complications. While rare, metastatic abscesses following appendectomy warrant consideration, particularly in K. pneumoniae infections. Comprehensive clinical assessment, imaging, and laboratory evaluation are crucial for timely diagnosis and management of such complications.

Unique Bilaterally Symmetrical Multifocal Osteomyelitis Presentation in a Health-care Worker with Sickle Cell Disease Secondary to Klebsiella Infection - A Case Report

Introduction

Osteomyelitis is one of the most common infectious complications in people with sickle cell disease (SCD). The most common infecting organisms in SCD are the Salmonella species and Staphylococcus aureus; Streptococcus pneumoniae and Bacteroides species have also been described, however, osteomyelitis attributable to infection with hypervirulent Klebsiella spp. is a rare entity. We describe our experience with a rare presentation of multifocal bilateral symmetrical ulna and fibula osteomyelitis in a patient with SCD due to Klebsiella bacteremia with 1-year follow-up.

Case Report

A 25-year-old female known SCD since childhood who underwent treatment for dengue at our hospital had her blood cultures positive for Klebsiella, following which she was treated with appropriate antibiotics. Two weeks following the asymptomatic period patient presented with complaints of pain over the bilateral forearm and legs. The patient was evaluated for laboratory parameters and plain radiograph of the bilateral forearm and bilateral legs. The radiological features were suggestive of osteomyelitis, showing "Bilaterally symmetrical involvement." Laboratory parameters erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were found raised. The patient was planned for biopsy and debridement of the lesion from the right ulna. The culture from the biopsy showed growth of Klebsiella sp. and was sensitive to co-trimoxazole. The patient was started on co-trimoxazole for 6 weeks and had a significant clinical improvement in the form of subsidence of pain, normalization of the blood counts along with the acute phase reactants (ESR, CRP).

Conclusion

Our case contributes to the growing awareness of the unusual manifestations of this serious disease and the rarity of bilateral symmetrical involvement. Our case highlights the importance of clinician awareness, manifestations, and management of Klebsiella sp. hypervirulent strains.

General Overview of Klebsiella pneumonia: Epidemiology and the Role of Siderophores in Its Pathogenicity

The opportunistic pathogen Klebsiella pneumoniae (K. pneumoniae) can colonize mucosal surfaces and spread from mucosae to other tissues, causing fatal infections. Medical equipment and the healthcare setting can become colonized by Klebsiella species, which are widely distributed in nature and can be found in water, soil, and animals. Moreover, a substantial number of community-acquired illnesses are also caused by this organism worldwide. These infections are characterized by a high rate of morbidity and mortality as well as the capacity to spread metastatically. Hypervirulent Klebsiella strains are thought to be connected to these infections. Four components are critical to this bacterium's pathogenicity-the capsule, lipopolysaccharide, fimbriae, and siderophores. Siderophores are secondary metabolites that allow iron to sequester from the surrounding medium and transport it to the intracellular compartment of the bacteria. A number of variables may lead to K. pneumoniae colonization in a specific area. Risk factors for infection include local healthcare practices, antibiotic use and misuse, infection control procedures, nutrition, gender, and age.

A Case of Severe Chronic Multifocal Osteomyelitis of the Skull Caused by Klebsiella pneumoniae in Mali

Highly invasive infections caused by Klebsiella pneumonia, which includes bacteremia, liver abscess, meningitis, septic arthritis, and osteomyelitis, in not commonly seen in adult immunocompetent and immunocompromised patients. Here, we report an adult case of chronic multifocal osteomyelitis with severe cranial involvement caused by Klebsiella pneumonia. The patient has a 5-year history of orbital abscess and multiple scalp traumas. CT scan showed right temporal and periorbital osteolysis, multiple parietal osteolysis. The pus was collected twice and routine culture was positive for Klebsiella pneumoniae. Good clinical outcome was achieved with debridement and antibiotic treatment. Microbiologists and clinicians should promptly perform bacteriological cultures on biopsy specimens to facilitate diagnosis when imaging or intraoperative findings of bone infection are suspected, especially in the Mali population.

Synergy of Plant Essential Oils in Antibiotic Therapy to Combat Klebsiella pneumoniae Infections

Increased antibiotic resistance presents a health problem worldwide. The World Health Organization published a list of pathogens considered a priority for designing new treatments. Klebsiella pneumoniae (Kp) is a top-priority microorganism, highlighting the strains that produce carbapenemases. Developing new efficient therapies or complementing existing treatments is a priority, and essential oils (EOs) provide an alternative. EOs could act as antibiotic adjuvants and enhance antibiotic activity. Employing standard methodologies, the antibacterial activity of the EOs and their synergic effect with antibiotics were detected. A string test was used to identify the impact of the EOs over the hypermucoviscosity phenotype presented by Kp strains, and Gas Chromatography-Mass Spectrometry analysis identified EOs and the composition of EOs. The potential of EOs for designing synergistic therapies with antibiotics to combat the infection of KPC diseases was demonstrated. In addition, the alteration of the hypermucoviscosity phenotype was shown as the principal mechanism of a synergic action between EOs and antibiotics. The differential composition of the EOs lets us identify some molecules that will be analyzed. Synergic activity of EOs and antibiotics can provide a solid platform for combating multiresistant pathogens that represent a severe health sector problem, such as Kp infections.

The making of hypervirulent Klebsiella pneumoniae

Klebsiella pneumoniae is a notorious bacterium in clinical practice. Virulence, carbapenem-resistance and their convergence among K. pneumoniae are extensively discussed in this article. Hypervirulent K. pneumoniae (HvKP) has spread from the Asian Pacific Rim to the world, inducing various invasive infections, such as pyogenic liver abscess, endophthalmitis, and meningitis. Furthermore, HvKP has acquired more and more drug resistance. Among multidrug-resistant HvKP, hypervirulent carbapenem-resistant K. pneumoniae (Hv-CRKP), and carbapenem-resistant hypervirulent K. pneumoniae (CR-HvKP) are both devastating for their extreme drug resistance and virulence. The hypervirulence of HvKP is primarily attributed to hypercapsule, macromolecular exopolysaccharides, or excessive siderophores, although it has many other factors, for example, lipopolysaccharides, fimbriae, and porins. In contrast with classical determination of HvKP, that is, animal lethality test, molecular determination could be an optional and practical method after improvement. HvKP, including Hv-CRKP and CR-HvKP, has been progressing. R-M and CRISPR-Cas systems may play pivotal roles in such evolutions. Hv-CRKP and CR-HvKP, in particular the former, should be of severe concern due to their being more and more prevalent.

Hypermucoviscous Klebsiella pneumoniae invasive syndrome in a patient with diabetes without liver abscess

Klebsiella pneumoniae is part of the human gastrointestinal microbiota. It is also a well-known cause of community and nosocomial infections, involving mainly the lung and urinary tract. An invasive syndrome with liver abscess due to a new hypervirulent strain of K. pneumoniae was recently described. Several cases have been reported, mainly in Asia. Here, we show a case of a patient with an extrahepatic involvement affecting the lung and prostate.

Native bone and joint infections caused by extended-spectrum β-lactamase-producing Enterobacterales: experience of a reference centre in the Greater Paris area

Antibiotic treatment of native osteomyelitis caused by extended-spectrum β-lactamase-producing Enterobacterales (ESBL-PE) is a challenge. Limited epidemiological and outcome data are available. This retrospective cohort study included osteomyelitis patients with ESBL-PE infections treated in a reference centre for bone and joint infections (BJIs) between 2011-2019. Twenty-nine patients with native BJI (mean age, 44.4 ± 15.7 years) were analysed. Fifteen cases were paraplegic patients with ischial pressure sores breaching the hip capsule. Other cases included eight other hip infections, four tibial infections and two foot infections. Infections were mostly polymicrobial (n = 23; 79.3%), including Staphylococcus aureus (n = 13; 8 methicillin-resistant). Klebsiella pneumoniae (n = 13) was the most frequent ESBL-producing species identified, followed by Escherichia coli (n = 10), including 3 E. coli/K. pneumoniae co-infections, and Enterobacter spp. (n = 9). ESBL-PE were rarely susceptible to fluoroquinolones (n = 4; 13.8%). Most therapies were based on carbapenems (n = 22) and combination therapies (n = 19). The median duration of treatment was 41 (5-60) days. Primary control of the infection was achieved in 62.1% (18/29) of cases and up to 86.2% after second look surgeries, after a median follow-up of 6 (1-36) months. Infection with ESBL-producing K. pneumoniae was associated with failure (P = 0.001), whereas age, infection location, prior colonisation and antimicrobial therapy were not found to be predictors of outcome. ESBL-PE native BJIs are often polymicrobial and fluoroquinolone-resistant infections caused by K. pneumoniae, highlighting the need for expert centres with pluridisciplinary meetings with experienced surgeons.

An unusual presentation, novel treatment with Meropenem PMMA beads and complications of Klebsiella osteomyelitis in a healthy adult- A case report

Osteomyelitis caused by Klebsiella Pneumoniae in a healthy adult person is rare. We present an unusual case of Klebsiella Pneumoniae osteomyelitis of both femurs in an immunocompetent adult. The infection was resistant to local debridement and got complicated with pathological fracture, ultimately leading to infected non-union. The challenges faced in the management of sequential complications while treating this atypical osteomyelitis are discussed. Unusual presentation of femur osteomyelitis due to Klebsiella pneumonia can happen in a healthy adult. The Meropenem PMMA beads can be valuable for treating Klebsiella osteomyelitis. Staged procedures might be helpful to improve the condition.

Virulence Factors in Hypervirulent Klebsiella pneumoniae

Hypervirulent Klebsiella pneumoniae (hvKP) has spread globally since first described in the Asian Pacific Rim. It is an invasive variant that differs from the classical K. pneumoniae (cKP), with hypermucoviscosity and hypervirulence, causing community-acquired infections, including pyogenic liver abscess, pneumonia, meningitis, and endophthalmitis. It utilizes a battery of virulence factors for survival and pathogenesis, such as capsule, siderophores, lipopolysaccharide, fimbriae, outer membrane proteins, and type 6 secretion system, of which the former two are dominant. This review summarizes these hvKP-associated virulence factors in order to understand its molecular pathogenesis and shed light on new strategies to improve the prevention, diagnosis, and treatment of hvKP-causing infection.

3-in-1: bilateral subcutaneous leg abscesses and liver abscess from Klebsiella pneumoniae

Hypervirulent strains of Klebsiella pneumoniae are known to cause liver abscesses and other metastatic infections. Being Asian and having diabetes are known host risk factors. Here we present an unusual case of a Filipino ballet dancer-choreographer with diabetes presenting with bilateral leg pains initially thought to be cellulitis, but was eventually diagnosed as bilateral subcutaneous leg abscesses. He also had a liver abscess, thankfully asymptomatic, which was only discovered on imaging. The occurrence of three distant abscesses in one patient, hence '3-in-1,' makes this case worth reporting. Bilateral subcutaneous leg abscesses as the presenting manifestation of this infection have not been reported yet. We hypothesise that his occupation which makes use of frequent contractions of leg muscles led to increased blood flow and preferentially directed blood-borne bacteria to localise in both legs. We have also characterised the pathogen with regards to its hypermucoviscous phenotype, capsular type, virulence genes and phylogeny.

A Rare Case of a Distal Humerus Pathological Fracture from Klebsiella Pneumoniae Osteomyelitis: A Case Report

Klebsiella pneumoniae is one of the leading causative organisms in pyogenic liver disease. It can cause disseminated infections, but rarely to bone, and rarely in healthy hosts. We report an unusual case of a distal humerus fracture from osteomyelitis secondary to dissemination in a non-immuno-compromised patient. The patient was surgically managed with external fixation and insertion of anti-biotic beads, in conjunction with medical therapy via culture direct antibiotics. This report highlights the diagnostic approach and treatment options for these atypical cases.

Hypervirulent Klebsiella pneumoniae - clinical and molecular perspectives

Hypervirulent Klebsiella pneumoniae (hvKp) has emerged as a concerning global pathogen. hvKp is more virulent than classical K. pneumoniae (cKp) and capable of causing community-acquired infections, often in healthy individuals. hvKp is carried in the gastrointestinal tract, which contributes to its spread in the community and healthcare settings. First recognized in Asia, hvKp arose as a leading cause of pyogenic liver abscesses. In the decades since, hvKp has spread globally and causes a variety of infections. In addition to liver abscesses, hvKp is distinct from cKp in its ability to metastasize to distant sites, including most commonly the eye, lung and central nervous system (CNS). hvKp has also been implicated in primary extrahepatic infections including bacteremia, pneumonia and soft tissue infections. The genetic determinants of hypervirulence are often found on large virulence plasmids as well as chromosomal mobile genetic elements which can be used as biomarkers to distinguish hvKp from cKp clinical isolates. These distinct virulence determinants of hvKp include up to four siderophore systems for iron acquisition, increased capsule production, K1 and K2 capsule types, and the colibactin toxin. Additionally, hvKp strains demonstrate hypermucoviscosity, a phenotypic description of hvKp in laboratory conditions that has become a distinguishing feature of many hypervirulent isolates. Alarmingly, multidrug-resistant hypervirulent strains have emerged, creating a new challenge in combating this already dangerous pathogen.

Global Evolution of Pathogenic Bacteria With Extensive Use of Fluoroquinolone Agents

It is well-established that the spread of many multidrug-resistant (MDR) bacteria is predominantly clonal. Interestingly the international clones/sequence types (STs) of most pathogens emerged and disseminated during the last three decades. Strong experimental evidence from multiple laboratories indicate that diverse fitness cost associated with high-level resistance to fluoroquinolones contributed to the selection and promotion of the international clones/STs of hospital-associated methicillin-resistant Staphylococcus aureus (HA-MRSA), extended-spectrum β-lactamase-(ESBL)-producing Klebsiella pneumoniae, ESBL-producing Escherichia coli and Clostridioides difficile. The overwhelming part of the literature investigating the epidemiology of the pathogens as a function of fluoroquinolone use remain in concordence with these findings. Moreover, recent in vitro data clearly show the potential of fluoroquinolone exposure to shape the clonal evolution of Salmonella Enteritidis. The success of the international clones/STs in all these species was linked to the strains' unique ability to evolve multiple energetically beneficial gyrase and topoisomerase IV mutations conferring high-level resistance to fluorquinolones and concomittantly permitting the acquisition of an extra resistance gene load without evoking appreciable fitness cost. Furthermore, by analyzing the clonality of multiple species, the review highlights, that in environments under high antibiotic exposure virulence factors play only a subsidiary role in the clonal dynamics of bacteria relative to multidrug-resistance coupled with favorable fitness (greater speed of replication). Though other groups of antibiotics should also be involved in selecting clones of bacterial pathogens the role of fluoroquinolones due to their peculiar fitness effect remains unique. It is suggested that probably no bacteria remain immune to the influence of fluoroquinolones in shaping their evolutionary dynamics. Consequently a more judicious use of fluoroquinolones, attuned to the proportion of international clone/ST isolates among local pathogens, would not only decrease resistance rates against this group of antibiotics but should also ameliorate the overall antibiotic resistance landscape.

Klebsiella pneumoniae-induced multiple invasive abscesses: A case report and literature review

RATIONALE

Klebsiella pneumoniae infection can induce multiple invasive abscesses, and the invasive infection is severe and life-threatening.

PATIENT CONCERNS

A 69-year-old previously healthy Chinese male presented with fever, chill, backache, and ocular pain.

DIAGNOSIS

The blood culture results indicated Klebsiella pneumoniae of the K1 serotype. Multiple invasive abscesses in liver, lung, eye, soft tissue, and central nervous system were identified by imaging examination. Subsequently, the patient experienced right ocular pain accompanied by visual disturbance. Tyndall sign was strongly positive, and lens opacity was observed by the ophthalmologist.

INTERVENTIONS

Full-dose and long-term treatment with meropenem was performed. Intraventricular injection of glass and anterior chamber puncture with antibiotics were performed twice. The patient also underwent an evacuation of the brain abscess.

OUTCOMES

The patient's headache and lumbar backache were relieved, his ophthalmodynia disappeared, and his vision recovered after nearly 3 months of treatment.

LESSONS

Imaging examination is very important for severe Klebsiella pneumoniae infection. The choice of antibiotics is complex, and the antimicrobial regimen should be adjusted according to the assessment of illness and the therapeutic effect. Surgical intervention must be considered for patients with multiple invasive abscesses.

Hypervirulent Klebsiella pneumoniae

Hypervirulent K. pneumoniae (hvKp) is an evolving pathotype that is more virulent than classical K. pneumoniae (cKp). hvKp usually infects individuals from the community, who are often healthy. Infections are more common in the Asian Pacific Rim but are occurring globally. hvKp infection frequently presents at multiple sites or subsequently metastatically spreads, often requiring source control. hvKp has an increased ability to cause central nervous system infection and endophthalmitis, which require rapid recognition and site-specific treatment. The genetic factors that confer hvKp's hypervirulent phenotype are present on a large virulence plasmid and perhaps integrative conjugal elements. Increased capsule production and aerobactin production are established hvKp-specific virulence factors. Similar to cKp, hvKp strains are becoming increasingly resistant to antimicrobials via acquisition of mobile elements carrying resistance determinants, and new hvKp strains emerge when extensively drug-resistant cKp strains acquire hvKp-specific virulence determinants, resulting in nosocomial infection. Presently, clinical laboratories are unable to differentiate cKp from hvKp, but recently, several biomarkers and quantitative siderophore production have been shown to accurately predict hvKp strains, which could lead to the development of a diagnostic test for use by clinical laboratories for optimal patient care and for use in epidemiologic surveillance and research studies.