Predictors of hypervirulent Klebsiella pneumoniae infections: a systematic review and meta-analysis.

BACKGROUND: Hypervirulent Klebsiella pneumoniae (hvKp) infections confer notable morbidity and mortality. Differential diagnosis to determine whether the infections are caused by either the hvKp or classical K. pneumoniae (cKp) strain is particularly important for undertaking optimal clinical care and infection control efforts. AIM: To identify and assess the potential predictors of hvKp infections. METHODS: PubMed, Web of Science, and Cochrane Library databases were searched for all relevant publications from January 2000 to March 2022. The search terms included a combination of the following terms: (i) Klebsiella pneumoniae or K. pneumoniae and (ii) hypervirulent or hypervirulence. A meta-analysis of factors for which risk ratio was reported in three or more studies was conducted, and at least one statistically significant association was identified. FINDINGS: In this systematic review of 11 observational studies, a total of 1392 patients with K. pneumoniae infection and 596 (42.8%) with hvKp strains were evaluated. In the meta-analysis, diabetes mellitus and liver abscess (pooled risk ratio: 2.61 (95% confidence interval: 1.79-3.80) and 9.04 (2.58-31.72), respectively; all P < 0.001) were predictors of hvKp infections. CONCLUSION: For patients with a history of the abovementioned predictors, prudent management, including the search for multiple sites of infection and/or metastatic spread and the enforcement of an early and appropriate source control procedure, should be initiated in consideration of the potential presence of hvKp. We believe that this research highlights the urgent need for increasing clinical awareness of the management of hvKp infections.

A comparison of the effect of large and small metal-on-metal bearings in total hip arthroplasty on metal ion levels and the incidence of pseudotumour: a five-year follow-up of a previous report.

Aims: The purpose of this study was to compare two different types of metal-on-metal (MoM) bearing for total hip arthroplasty (THA): one with a large femoral head (38 mm to 52 mm) and the other with a conventional femoral head (28 mm or 32 mm). We compared clinical outcome, blood metal ion levels, and the incidence of pseudotumour in the two groups. Patients and Methods: Between December 2009 and December 2011, 62 patients underwent MoM THA with a large femoral head (Magnum group) and 57 patients an MoM THA with a conventional femoral head (conventional group). Clinical outcome was assessed using the Harris Hip score, University of California, Los Angeles (UCLA) activity score and EuroQol-5D (EQ-5D). Blood metal ion levels were measured and MRI scans were analyzed at a minimum of five years postoperatively. Results: No acetabular component was implanted with more than 50° of inclination in either group. The Harris Hip Score, UCLA activity score, and EQ-5D improved postoperatively in both groups; no significant clinical differences were noted between the groups. The blood cobalt ion levels in the conventional group continued to rise postoperatively to five years while reaching a plateau at two years postoperatively in the Magnum group. At five years, the mean cobalt ion level of 1.16 µg/l (sd 1.32) in the Magnum group was significantly lower than the 3.77 µg/l (sd 9.80) seen in the conventional group (p = 0.0015). The incidence of moderate to severe pseudotumour was 4.7% in the Magnum group and 20.6% in the conventional group. There were no dislocations in the Magnum group and two in the conventional group. One patient in the Magnum group underwent revision for pseudotumour at 4.7 years postoperatively. Conclusion: At five years, a well-positioned large head MoM THA has a significantly lower level of metal ion release and a lower incidence of moderate to severe pseudotumour than a MoM bearing of conventional size. Cite this article: Bone Joint J 2018;100-B:1018-24.

Criteria for preserving posterior cruciate ligament depending on intra-operative gap measurement in total knee replacement.

OBJECTIVES: Because posterior cruciate ligament (PCL) resection makes flexion gaps wider in total knee replacement (TKR), preserving or sacrificing a PCL affects the gap equivalence; however, there are no criteria for the PCL resection that consider gap situations of each knee. This study aims to investigate gap characteristics of knees and to consider the criteria for PCL resection. METHODS: The extension and flexion gaps were measured, first with the PCL preserved and subsequently with the PCL removed (in cases in which posterior substitute components were selected). The PCL preservation or sacrifice was solely determined by the gap measurement results, without considering other functions of the PCL such as 'roll back.' RESULTS: Wide variations were observed in the extension and flexion gaps. The flexion gaps were significantly larger than the extension gaps. Cases with 18 mm or more flexion gap and with larger flexion than extension gap were implanted with cruciate retaining component. A posterior substitute component was implanted with the other cases. CONCLUSIONS: In order to make adequate gaps, it is important to decide whether to preserve the PCL based on the intra-operative gap measurements made with the PCL intact. Cite this article: Bone Joint Res 2014;3:95-100.

Spontaneous repair of asymptomatic osteonecrosis associated with corticosteroid therapy in systemic lupus erythematosus: 10-year minimum follow-up with MRI.

Systemic lupus erythematosus (SLE) patients are at high risk of developing osteonecrosis. This study utilized MRI to document the long-term natural history of asymptomatic osteonecrosis associated with corticosteroid therapy in SLE patients. Two hundred and one SLE patients treated with high-dose corticosteroids were prospectively observed from 1986 to 1997. The inclusion criterion was that patients had received periodic MRI examinations of all their hip and knee joints for ≥10 years. Joints that were already collapsed and symptomatic at the first examination were excluded. Five hundred and thirty-seven joints (251 hips and 286 knees) were identified in 144 patients, with a mean follow-up period of 13.6 years (range, 10-20 years) and a follow-up rate of 73%. Mean age of SLE onset was 26 years, and the mean highest oral corticosteroid dosage was 57 mg/day. Osteonecrosis developed in 238 (44%) of 537 joints. At final follow-up, 117 (49%) of these 238 joints demonstrated spontaneous repair in the necrotic area. Osteonecrosis completely disappeared in 21 joints. Enlargement of osteonecrosis was noted in 35 joints (15%) following increased steroid dosage because of SLE recurrence. Finally, 52 joints (22%) were collapsed. Spontaneous repair of asymptomatic osteonecrosis was observed, whereas enlargement occurred only after corticosteroid dosage increases.

Osteonecrosis in patients with systemic lupus erythematosus develops very early after starting high dose corticosteroid treatment.

OBJECTIVES: To investigate the actual time of onset of osteonecrosis (ON) after high dose corticosteroid treatment in systemic lupus erythematosus (SLE). METHODS: 72 patients with active SLE, who received high dose corticosteroid for the first time, for the development of ON at hips and knees were monitored by magnetic resonance imaging for at least 12 months. RESULTS: ON lesions were detected in 32/72 patients (44%) between one and five months (3.1 months on average) after starting high dose corticosteroid treatment. No osteonecrotic lesion was newly detected from the sixth month of treatment until the end of the follow up period. CONCLUSION: The findings suggested that the actual time of onset of ON in SLE is within the first month of high dose corticosteroid treatment.

Sustained hemostatic abnormality in patients with steroid-induced osteonecrosis in the early period after high-dose corticosteroid therapy.

To determine whether the development of steroid-induced osteonecrosis in collagen disease patients was related to hemostatic abnormality after corticosteroid administration, we examined levels of thrombin-antithrombin III complex (TAT) and plasmin-alpha2-plasmin inhibitor complex (PIC) in 32 patients who were treated with high-dose corticosteroid. All were prospectively followed for osteonecrosis, with serial magnetic resonance imaging (MRI), for at least 12 months from the beginning of corticosteroid therapy. MRI was performed on bilateral hips and knees. Of the 32 patients, 17 (53.1%) had osteonecrosis in the hip or knee. Osteonecrosis was detected on MRI at an average 3.1 months after the start of high-dose corticosteroid therapy. PIC levels were significantly higher in the group of 17 patients with osteonecrosis (ON group) than in the group of 15 patients without osteonecrosis (non-ON group) (P < 0.0001). The difference in PIC levels was most prominent 20 days after the start of the high-dose corticosteroid therapy. Moreover, the number of osteonecrotic joints was significantly correlated with PIC levels (P < 0.0001). The sustained hemostatic abnormality after corticosteroid therapy in the ON group suggests that microvascular coagulation participates in the development of osteonecrosis.

Acetabular labrum: abnormal findings at MR imaging in asymptomatic hips.

PURPOSE: To determine the prevalence of abnormalities of the acetabular labrum in asymptomatic hips by means of magnetic resonance (MR) imaging and to correlate such abnormalities with age and the portion of the labrum. MATERIALS AND METHODS: MR imaging was performed in 71 asymptomatic hips that were radially sectioned perpendicular to the acetabular labrum at 30 degrees intervals. RESULTS: The shape of the labrum was triangular in 80% (304 of 382) of the labral segments, round in 13% (49 of 382), irregular in 7% (27 of 382), and not identified in 1% (two of 382). A homogeneous low signal intensity was observed in 56% (212 of 382). The frequencies of labral irregularity or its absence and of high signal intensity increased both with subject age and with a more anterior anatomic labral location. CONCLUSION: In asymptomatic hips, abnormal findings regarding the shape and signal intensity of the acetabular labrum can be detected by means of MR imaging. The fact that the findings vary according to age and labral portion should be considered in interpreting MR images in patients suspected of having a labral lesion.