Cryptogenic invasive Klebsiella pneumoniae liver abscess syndrome (CIKPLA) in Western Australia?

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.

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

Background

Hypervirulent strains of Klebsiella pneumoniae are a recognized cause of a distinct invasive syndrome that results in pyogenic liver abscesses and metastatic complications, particularly in the Asia Pacific region. Reports of hypervirulent K.pneumoniae in Europe, the Americas and Australia indicate worldwide spread. We present a case of multi-focal osteomyelitis, a rarely described complication of hypervirulent K.pneumoniae in the medical literature. The prevalence of this condition in countries outside Asia may be expected to rise with increasing travel.

Case presentation

A 20-year-old Chinese man residing in Australia for 2 years presented with a 2-week history of gradually worsening leg pain preceded by 2 weeks of constitutional symptoms. Imaging with computerized axial tomography (CT) and other modalities revealed bilateral tibial lesions described as lattice-like linear lucencies involving the cortices with scalloping of the outer involved cortex. Cultures of tissue from a left tibial bone biopsy were positive cultures for K.pneumoniae. Whole-genome sequencing identified the isolate as K1 serotype ST23, a well-recognized hyper virulent strain capable of causing invasive disease. An abdominal CT revealed a 27x22mm liver abscess. The patient had no other metastatic manifestations of the disease, and responded to 6 weeks of intravenous ceftriaxone followed by 3 months of oral Ciprofloxacin.

Conclusions

Increased awareness of the manifestations and subsequent management of hyper virulent strains of K.pneumoniae by clinicians is important to assist early recognition and help minimize serious sequelae. Cases with overseas links, such as previous residence in the Asia Pacific area, are at higher risk for infection with the hyper virulent strain. This case highlights the need for clinicians to be able to recognize this important disease, especially in patients with the right epidemiological links, and to investigate and treat appropriately to prevent severe metastatic complications.

Novel complication of an emerging disease: Invasive Klebsiella pneumoniae liver abscess syndrome as a cause of acute respiratory distress syndrome

Klebsiella pneumoniae is an increasingly recognized cause of a unique invasive syndrome manifesting as pyogenic liver abscess and hematogenous extrahepatic dissemination to a variety of sites, including the lung. Originally described only in Asia, this entity has now been reported across continents and ethnicities. Intrathoracic complications of invasive Klebsiella pneumoniae liver abscess syndrome (IKPLAS) have been characterized sporadically but have not been the subject of an all-encompassing investigation. Review of the English-language literature yields no reports of the acute respiratory distress syndrome as a consequence of IKPLAS. Herein we report what, to our knowledge, is the first such description.

Temporal flux in β-lactam resistance among Klebsiella pneumoniae in Western Australia

Our aim was to identify long-term β-lactam resistance trends in local Klebsiella pneumoniae isolates, which are a common cause of sepsis in Western Australia. We studied three collections of K. pneumoniae isolates from Western Australia between 1977 and 2015 comprising contemporary blood culture (n = 98), multiresistant (n = 21) and historical (n = 50) isolates. Antimicrobial resistance was determined by Clinical and Laboratory Standards Institute agar dilution methods. PCR DNA sequencing identified β-lactamase variants and porin mutations contributing to β-lactam resistance. Isolates were genotyped by PFGE, multilocus sequence typing and a variable number tandem repeat method. From 1989 onwards, we detected the SHV-2a extended-spectrum β-lactamase (ESBL) in ceftriaxone-resistant isolates, and in ceftazidime- and aztreonam-resistant isolates from 1993. Ceftriaxone, ceftazidime and aztreonam resistance persisted, with blaCTX-M types becoming the dominant ESBLs by 2010. CTX-M-15 was encountered in both multiresistant and blood culture isolates. Meropenem resistance was detected for the first time in 2011 in a locally isolated blaIMP-4-positive K. pneumoniae. We found sequence types ST23 and ST86 that occurred in multiple isolates from invasive infections. ST86 was the most common and maintained a high degree (90 %) of similarity by PFGE since 1977. Ceftazidime-resistant K. pneumoniae sequence types have caused invasive infections in Western Australia since 1993. Invasive isolates producing CTX-M-14 and CTX-M-15 appeared in Western Australia during the last decade, before the appearance of carbapenemases. The diversity of β-lactam resistance and β-lactamase resistance mechanisms in Western Australian K. pneumoniae has increased since ESBLs were first described locally.

Percutaneous aspiration versus catheter drainage of liver abscess: A retrospective review

BACKGROUND

A review of the effectiveness and outcomes in liver abscess drainage performed by different operators using percutaneous aspiration (PA) and catheter drainage (PCD), respectively, from 2008-2013 at Sir Charles Gairdner Hospital, a tertiary hospital in Australia.

METHODS

Forty-two patients (29 males and 13 females; aged between 28-93 years; median age of 67 years) with liver abscesses underwent either ultrasound or CT-guided PA (n=22) and PCD (n=20) in conjunction with appropriate antimicrobial therapy. A median of 18 Gauge needle and 10 French catheters were utilised.

RESULTS

Nineteen (86.4 per cent) PA cases and 12 (60 per cent) PCD cases were successfully drained on a single attempt (p=0.08). More male patients (69 per cent) than females (31 per cent) were observed. Portal sepsis (42.9 per cent) was the most common cause identified. Fever (47.6 per cent) was the most frequent clinical presentation on admission. Thirty-two patients (76.2 per cent) had solitary abscesses with a right lobe (59.5 per cent) predilection. CRP was significantly raised. The PCD group observed a significantly larger abscess size (p=0.01). Klebsiella pneumoniae was the most common organism isolated in both pus (33.3 per cent) and blood cultures (11.9 per cent). Five procedure-related complications were noted, all in the PCD group. Thirty-day mortality was 2.4 per cent. No difference was observed in clinical and treatment outcomes in both groups.

CONCLUSION

The null hypothesis that both PA and PCD are equally effective in the drainage of liver abscess cannot be rejected. Apart from PA being simpler and safer to perform, the higher incidence of indwelling catheter-associated complications suggests that a trial of PA should always be attempted first.