Ten-year retrospective review of paediatric septic arthritis in a New Zealand centre

Hospitalisation cost for paediatric osteomyelitis and septic arthritis in New Zealand

AIM

Hospitalisation rates for paediatric bone and joint infection (BJI) in New Zealand (NZ) are among the highest globally. This study aims to quantify hospitalisation costs of BJI in 2018-2019.

METHODS

National hospitalisation data from the NZ Ministry of Health was used to describe costs associated with all paediatric hospitalisations coded for osteomyelitis or septic arthritis in those aged <16 years. Data included age, ethnic group, area level deprivation, diagnosis-related-group coding, admission length and cost-weight. Readmissions up to 24 months following the initial encounter were analysed for associated costs.

RESULTS

More than ten million dollars was spent on hospitalisation for paediatric BJI over the study period (NZ$10 819 474). There were 869 primary hospitalisations and 229 related readmissions. Median length of stay was 7.4 days (95% confidence interval 6.8-7.9). Re-admission costs were NZ$1 196 640 within 24 months following diagnosis. Higher median hospitalisation costs occurred for children residing in the most deprived versus least deprived neighbourhoods (NZ$12 126 vs. NZ$9010, P < 0.01). NZ Māori compared with non-Māori children had longer length of stay (8.4 vs. 6.3 days, P = 0.04), more complex and severe illnesses (53% vs. 17%, P < 0.01), and higher median hospitalisation costs (NZ$11 796 vs. NZ$9581, P = 0.03).

CONCLUSIONS

Direct BJI hospitalisation costs in 2018-2019 were NZ$10 819 474 with 11% of costs due to re-admission. Direct hospitalisation costs for paediatric BJI in NZ vary by deprivation and ethnic group. Illness complexity of paediatric BJI varies by ethnic group. Interventions are needed to reduce incidence and severity of these debilitating infections.

The feasibility and safety of ultrasound-guided puncture for treatment of septic arthritis in children

BACKGROUND

In septic arthritis, joint lavage can be performed using arthrocentesis (articular needle aspiration) or arthrotomy. The use of fluoroscopy to guide the puncture involves radiation. Ultrasound (US) guidance is still little recommended to guide the treatment of septic arthritis in children. We wanted to know whether treating septic arthritis in children was feasible and safe under ultrasound (US) guidance.

METHODS

We retrospectively included 67 children (mean age, 3.0 years; range: 1 month-12 years) treated for septic arthritis of the hip, shoulder, or ankle using arthrocentesis or arthrotomy under US or fluoroscopic guidance (non-US group) with at least two years of follow-up.

RESULTS

We found no significant difference between the groups. After arthrocentesis, patients in the US group remained in hospital for 0.8 days longer than those in the non-US group, but the difference was not significant. After arthrotomy, the arthrotomy-US group required 0.4 more days of hospitalization than the non-US group, but the difference was not significant. Patients in the US group exhibited higher initial CRP and WBC values than patients treated without US, although the differences were not significant. The WBC values of the arthrocentesis-US groups were higher than those of the non-US groups initially and at 72 h, but non significantly so; they became similar on day 5. Three puncture failures required arthrotomy (two under US guidance). Three patients required early revision surgery: one had undergone arthrocentesis with US, one arthrocentesis without US, and one arthrotomy without US. At the last follow-up, there were no clinical sequelae but two hip arthrotomies (one US and one non-US child) showed asymptomatic calcifications.

CONCLUSIONS

US guidance is feasible and safe for treating septic arthritis in children, visualizing structures not shown by X-rays and avoiding radiation exposure during surgery.

LEVEL OF EVIDENCE

IV (case series).

TRIAL REGISTRATION

IRB-MTP_2021_05_202100781.

Epidemiology of childhood bone and joint disease during the COVID-19 pandemic in New Zealand

PURPOSE

It is unknown whether social distancing impacts frequency of presentation and severity of childhood bone and joint infection (BJI). In New Zealand, the COVID-19 disease elimination strategy involved strict social isolation policies spanning March 2020-September 2022. Examination of this period may provide insight around risk factors for BJI.

METHODS

A retrospective review of all patients < 16 years with presumed acute haematogenous osteomyelitis (AHO) or septic arthritis (SA) treated in the Auckland region was performed between 2018 and 2023. Frequency and severity of presentations has been examined before, during, and after periods of social restriction. Severe cases included those with intensive care admission, recurrent infection, or multiple surgeries. Pre-hospital experience, length of stay, and disease outcomes have also been assessed.

RESULTS

A total of 563 cases met inclusion criteria. Compared to the pre-pandemic period, monthly case averages reduced between April 2020 to September 2022 (10.1 vs. 7.9 cases/month, p = 0.008). Separating cases by causative microbiology shows a statistically significant drop in culture negative and Kingella kingae mediated BJI cases (4.2 vs. 2.9 cases/month, p = 0.006) but not for cases secondary to Staphylococcus aureus and Streptococcus pyogenes (4.2 vs. 3.9 cases/month, p = 0.6). The frequency of severe disease reduced during this period (5.6 vs. 4.1 cases/month, p = 0.01) together with lower rates of recurrent infection (9% vs. 4%, p = 0.03).

CONCLUSION

The COVID-19 management strategy in New Zealand utilised strict social isolation, mask wearing, and hand hygiene measures to control disease spread between 2020 and 2022. These measures coincided with reduction in frequency and severity of presentations for childhood BJI.

Outcomes of paediatric septic arthritis patients: rates of re-admission, re-operation, and unplanned emergency room visits after discharge

PURPOSE

This study is aimed at determining the rates and predictors of re-operation and re-admission in children with septic arthritis treated at an institution without routine clinical practice guidelines.

METHODS

This is a retrospective cohort study of patients less than 18 years old who underwent surgery for septic arthritis between January 1, 2009, and January 1, 2019, at a single tertiary-care paediatric institution. Uni- and multivariate analysis was performed to identify any risk factors associated with re-operation or unplanned visits to the emergency department after hospital admission compared to patients who had an uncomplicated post-operative course.

RESULTS

One hundred and forty-four patients were included. The mean age was five years (range 1 month-17 years), and the most commonly affected joint was the hip. The re-admission rate was 1% (n = 2), and the re-operation rate was 8% (n = 12). Twenty percent of patients (n = 29) had unplanned presentations to the emergency department (ED) after discharge. Discharge CRP level was not significantly higher in patients with unplanned presentations to the ED or re-operation. Positive joint fluid culture and infection of any other joint than the hip increased the likelihood of re-operation. Patients who had septic arthritis of the hip were more likely to have an unplanned ED presentation.

CONCLUSIONS

Rates of re-admission and re-operation were similar to literature despite lack of a standardized treatment pathway or discharge protocol. Outcomes of pediatric septic arthritis did not correlate with discharge CRP level. There was a high rate of unplanned ED visits after discharge.

Methods to Reduce Cost of Treatment in Childhood Bone and Joint Infection: A Systematic Review

BACKGROUND

Childhood bone and joint infection (BJI) is a potentially severe disease with consequences for growth and development. Critically unwell children may require prolonged hospitalization and multiple surgeries. Acknowledging rising healthcare costs and the financial impact of illness on caregivers, increased efforts are required to optimize treatment. This systematic review aims to characterize existing costs of hospital care and summarize strategies, which reduce treatment expense.

METHODS

A systematic review of the literature was performed from January 1, 1980, to January 31, 2024. Data were extracted on hospitalization costs for pediatric BJI by decade and global region. Results have been converted to cost per day in US dollars with purchase parity for 2023. Studies reporting innovations in clinical care to reduce length of stay (LOS) and simplify treatment were identified. Studies trialing shorter antibiotic treatment were only included if they specifically reported changes in LOS.

RESULTS

Twenty-three studies met inclusion criteria; of these, a daily hospitalization cost could be derived from 7 publications. Overall hospitalization cost and inpatient charges rose steeply from the 1990s to the 2020s. By contrast, average LOS seems to have decreased. Cost per day was higher in the United States than in Europe and higher for cases with confirmed methicillin-resistant Staphylococcus aureus. Sixteen studies report innovations to optimize care. For studies where reduced LOS was achieved, early magnetic resonance imaging with immediate transfer to theater when necessary and discharge on oral antibiotics were consistent features.

CONCLUSION

Rising costs of hospital care and economic consequences for families can be mitigated by simplifying treatment for childhood BJI. Hospitals that adopt protocols for early advanced imaging and oral antibiotic switch may provide satisfactory clinical outcomes at lower cost.

LEVEL OF EVIDENCE

Level III. See Instructions for Authors for a complete description of levels of evidence.

An Update on Pediatric Acute Hematogenous Osteomyelitis in New Zealand - A Decade on

INTRODUCTION

New Zealand (NZ) has high rates of pediatric acute hematogenous osteomyelitis (AHO) with males and children of Pasifika and Māori ethnicity overrepresented.

AIMS

To update the incidence of Pediatric AHO over 10 years, identifying trends in presentation, organisms, treatment, and outcomes.

METHODS

A 10-year retrospective review of children aged 6 weeks to 15 years admitted with Pediatric AHO across two centers from 2008 to 2017. Demographic data, features of presentation, investigations, management, and complications were collected. Incidence was calculated from census data. Data were compared with our osteomyelitis database from the previous decade. (1).

RESULTS

796 cases were identified. The incidence was 18 per 100,000 per annum. The average age was 7.7 years. Pasifika and Māori children are overrepresented (57%). 370 children (51%) came from low socioeconomic areas. Methicillin-sensitive Staphylococcus aureus was the most common pathogen (87%). Methicillin-resistant Staphylococcus aureus (MRSA) rates are low (4.4%). Forty-four (5.5%) children were admitted to the Pediatric Intensive Care Unit (PICU) with 9% mortality. The mean duration of antibiotics was 40 days. 325 children (41%) had surgery. Chronic infection has increased from 1.7% to 5.7%.

CONCLUSIONS

NZ has high rates of AHO, however, the incidence has decreased from the previous decade. Males, those in low socioeconomic areas, Pasifika and Māori have high disease burden. The use of MRI as a diagnostic modality has increased. Future studies should focus on improving treatment via prospective analysis and reporting long-term morbidity to improve outcomes for children with severe disease and reduce rates of chronic infection.

Ten-year Review of Acute Pediatric Hematogenous Osteomyelitis at a New Zealand Tertiary Referral Center

BACKGROUND

Acute hematogenous osteomyelitis (AHO) remains a cause of severe illness among children with the possibility of long-term consequences for growth and development. Recent research has highlighted an unusually high burden of disease in the New Zealand population compared with other Western regions. We have sought to identify trends in presentation, diagnosis, and management of AHO, with added focus on ethnicity and access to health care.

METHODS

A 10-year retrospective review of all patients <16 years with presumed AHO presenting to a tertiary referral center between 2008 and 2018 was performed.

RESULTS

One hundred fifty-one cases met inclusion criteria. The median age was 8 years with a male predominance (69.5%). Staphylococcus aureus was the most common pathogen using traditional laboratory culture method (84%). The number of cases per year decreased from 2008 to 2018. Assessment using New Zealand deprivation scores showed Māori children were most likely to experience socioeconomic hardship ( P ≤0.01). Median distance traveled by families to first hospital consult was 26 km (range 1 to 178 km). Delayed presentation was associated with need for prolonged antibiotic therapy. Incidence of disease varied by ethnicity with 1:9000 cases per year for New Zealand European, 1:6500 for Pacific, and 1:4000 for Māori. Overall recurrence rate was 11%.

CONCLUSIONS

The incidence of AHO in New Zealand is concerningly high within Māori and Pacific populations. Future health interventions should consider environmental, socioeconomic, and microbiological trends in the burden of disease.

LEVEL OF EVIDENCE

Retrospective study, Level III.

Early CRP Trends in Childhood Osteomyelitis Predict Complicated Disease

BACKGROUND

Acute hematogenous osteomyelitis (AHO) remains a cause of severe illness among children. Contemporary research aims to identify predictors of acute and chronic complications. Trends in C-reactive protein (CRP) after treatment initiation may predict disease course. We have sought to identify factors associated with acute and chronic complications in the New Zealand population.

METHODS

A retrospective review of all patients younger than16 years with presumed AHO presenting to a tertiary referral centre between 2008 and 2018 was performed. Multivariate was analysis used to identify factors associated with an acute or chronic complication. An "acute" complication was defined as the need for 2 or more surgical procedures, a hospital stays longer than 14 days, or recurrence despite intravenous antibiotics. A "chronic" complication was defined as growth or limb length discrepancy, avascular necrosis, chronic osteomyelitis, pathologic fracture, frozen joint, or dislocation.

RESULTS

One hundred fifty-one cases met the inclusion criteria. The median age was 8 years (69.5% male). Within this cohort, 53 (34%) experienced an acute complication and 18 (12%) a chronic complication. Regression analysis showed that contiguous disease, delayed presentation, and failure to reduce CRP by 50% at day 4/5 predicted an acutely complicated disease course. Chronic complication was predicted by the need for surgical management and failed CRP reduction by 50% at day 4/5.

CONCLUSIONS

CRP trends over 96 hours after the commencement of treatment differentiate patients with AHO likely to experience severe disease.

LEVEL OF EVIDENCE

Level II, retrospective study.

Predictive Algorithms in the Diagnosis and Management of Pediatric Hip and Periarticular Infection

➤ Although the criteria of Kocher et al. were an important advancement in our ability to diagnose septic arthritis of the hip early, the changing microbial landscape and availability of advanced imaging have rendered it insufficient for contemporary clinical use.➤ Routine use of magnetic resonance imaging and recognition of disseminated disease have prompted the development of algorithms to predict concurrent osteoarticular infection in cases of septic arthritis and osteomyelitis that were previously assumed to be "isolated."➤ Recent research has attempted to stratify childhood bone and joint infection (BJI) by severity to guide treatment planning. This is valuable, as patients with multifocal disease, more virulent pathogens, and immunocompromise can have longer hospital stays and require multiple surgeries.➤ The increasing prevalence of clinical prediction algorithms in childhood BJI is not completely matched by quality in methodology. Clinicians need to be wary of adopting predictive algorithms prior to robust external validation.