Appendicitis risk prediction models in children presenting with right iliac fossa pain (RIFT study): a prospective, multicentre validation study

BACKGROUND

Acute appendicitis is the most common surgical emergency in children. Differentiation of acute appendicitis from conditions that do not require operative management can be challenging in children. This study aimed to identify the optimum risk prediction model to stratify acute appendicitis risk in children.

METHODS

We did a rapid review to identify acute appendicitis risk prediction models. A prospective, multicentre cohort study was then done to evaluate performance of these models. Children (aged 5-15 years) presenting with acute right iliac fossa pain in the UK and Ireland were included. For each model, score cutoff thresholds were systematically varied to identify the best achievable specificity while maintaining a failure rate (ie, proportion of patients identified as low risk who had acute appendicitis) less than 5%. The normal appendicectomy rate was the proportion of resected appendixes found to be normal on histopathological examination.

FINDINGS

15 risk prediction models were identified that could be assessed. The cohort study enrolled 1827 children from 139 centres, of whom 630 (34·5%) underwent appendicectomy. The normal appendicectomy rate was 15·9% (100 of 630 patients). The Shera score was the best performing model, with an area under the curve of 0·84 (95% CI 0·82-0·86). Applying score cutoffs of 3 points or lower for children aged 5-10 years and girls aged 11-15 years, and 2 points or lower for boys aged 11-15 years, the failure rate was 3·3% (95% CI 2·0-5·2; 18 of 539 patients), specificity was 44·3% (95% CI 41·4-47·2; 521 of 1176), and positive predictive value was 41·4% (38·5-44·4; 463 of 1118). Positive predictive value for the Shera score with a cutoff of 6 points or lower (72·6%, 67·4-77·4) was similar to that of ultrasound scan (75·0%, 65·3-83·1).

INTERPRETATION

The Shera score has the potential to identify a large group of children at low risk of acute appendicitis who could be considered for early discharge. Risk scoring does not identify children who should proceed directly to surgery. Medium-risk and high-risk children should undergo routine preoperative ultrasound imaging by operators trained to assess for acute appendicitis, and MRI or low-dose CT if uncertainty remains.

FUNDING

None.

Protection against lethal equine herpes virus type 1 (subtype 1) infection in hamsters by immune stimulating complexes (ISCOMs) containing the major viral glycoproteins

An experimental ISCOM vaccine has been prepared from gradient purified equine herpes virus type 1 (EHV-1). Radiolabelling studies demonstrated that this vaccine contained all the major viral glycoproteins in relative amounts similar to those found in non-detergent disrupted viral preparations. This EHV-1 ISCOM vaccine generated fully protective responses in hamsters challenged with an otherwise lethal dose of the hamster-adapted EHV-1 strain RACH.

Correlates of 1-Year Change in Quality of Life in Patients with Urologic Chronic Pelvic Pain Syndrome: Findings from the Multidisciplinary Approach to the Study of Chronic Pelvic Pain (MAPP) Research Network

PURPOSE

We evaluated and identified baseline factors associated with change in health related quality of life among patients with interstitial cystitis/bladder pain syndrome and chronic prostatitis/chronic pelvic pain syndrome.

MATERIALS AND METHODS

A total of 191 men and 233 women with interstitial cystitis/bladder pain syndrome or chronic prostatitis/chronic pelvic pain syndrome (collectively referred to as urologic chronic pelvic pain syndrome) were followed for 12 months with bimonthly completion of the Short Form 12 to assess general mental and physical health related quality of life, and with biweekly assessment of condition specific health related quality of life using the Genitourinary Pain Index. A functional clustering algorithm was used to classify participants as improved, stable or worsened for each health related quality of life measure. Ordinal logistic regression was used to determine baseline factors associated with change.

RESULTS

Physical health related quality of life improved in 22% of the participants, mental health related quality of life improved in 25% and condition specific health related quality of life improved in 47%. Better baseline physical health related quality of life, older age and the presence of nonurological symptoms were associated with lower likelihood of improvement in physical health related quality of life. Better baseline mental health related quality of life, female sex, and greater baseline depression and stress were associated with a lower likelihood of improvement in mental health related quality of life. Better baseline condition specific health related quality of life and more severe baseline urologic chronic pelvic pain syndrome pain symptoms were associated with a lower likelihood of improvement in condition specific health related quality of life.

CONCLUSIONS

While several nonurologic chronic pelvic pain syndrome factors influenced the trajectory of general health related quality of life over time, only condition specific baseline health related quality of life and urologic chronic pelvic pain syndrome symptoms were associated with urologic chronic pelvic pain syndrome specific health related quality of life change. Significant differences in how urologic chronic pelvic pain syndrome impacts various aspects of health related quality of life suggest a multidisciplinary approach to assessment and treatment of these patients.

The Role of Mitochondria in Optic Atrophy With Autosomal Inheritance

Optic atrophy (OA) with autosomal inheritance is a form of optic neuropathy characterized by the progressive and irreversible loss of vision. In some cases, this is accompanied by additional, typically neurological, extra-ocular symptoms. Underlying the loss of vision is the specific degeneration of the retinal ganglion cells (RGCs) which form the optic nerve. Whilst autosomal OA is genetically heterogenous, all currently identified causative genes appear to be associated with mitochondrial organization and function. However, it is unclear why RGCs are particularly vulnerable to mitochondrial aberration. Despite the relatively high prevalence of this disorder, there are currently no approved treatments. Combined with the lack of knowledge concerning the mechanisms through which aberrant mitochondrial function leads to RGC death, there remains a clear need for further research to identify the underlying mechanisms and develop treatments for this condition. This review summarizes the genes known to be causative of autosomal OA and the mitochondrial dysfunction caused by pathogenic mutations. Furthermore, we discuss the suitability of available in vivo models for autosomal OA with regards to both treatment development and furthering the understanding of autosomal OA pathology.

Novel in vivo models of autosomal optic atrophy reveal conserved pathological changes in neuronal mitochondrial structure and function

Autosomal optic atrophy (AOA) is a form of hereditary optic neuropathy characterized by the irreversible and progressive degermation of the retinal ganglion cells. Most cases of AOA are associated with a single dominant mutation in OPA1, which encodes a protein required for fusion of the inner mitochondrial membrane. It is unclear how loss of OPA1 leads to neuronal death, and despite ubiquitous expression appears to disproportionately affect the RGCs. This study introduces two novel in vivo models of OPA1-mediated AOA, including the first developmentally viable vertebrate Opa1 knockout (KO). These models allow for the study of Opa1 loss in neurons, specifically RGCs. Though survival is significantly reduced in Opa1 deficient zebrafish and Drosophila, both models permit the study of viable larvae. Moreover, zebrafish Opa1 KO larvae show impaired visual function but unchanged locomotor function, indicating that retinal neurons are particularly sensitive to Opa1 loss. Proteomic profiling of both models reveals marked disruption in protein expression associated with mitochondrial function, consistent with an observed decrease in mitochondrial respiratory function. Similarly, mitochondrial fragmentation and disordered cristae organization were observed in neuronal axons in both models highlighting Opa1's highly conserved role in regulating mitochondrial morphology and function in neuronal axons. Importantly, in Opa1 deficient zebrafish, mitochondrial disruption and visual impairment precede degeneration of RGCs. These novel models mimic key features of AOA and provide valuable tools for therapeutic screening. Our findings suggest that therapies enhancing mitochondrial function may offer a potential treatment strategy for AOA.

P108 Acetazolamide for obstructive hydrocephalus in the pregnant female: a case report and literature review

Objectives

This study presents a case report and literature review of acetazolamide use in the pregnant patient to further delineate its role and controversies in the treatment of symptomatic hydrocephalus. Here we present a case from our neurosurgical service which demonstrated safe use and efficacy of acetazolamide in refractory hydrocephalus secondary to a space-occupying lesion.

Design

Case report and literature review.

Subjects

33-year-old, primigravid female treated at Charing Cross Hospital, London.

Methods

Adaptation of the PRISMA guideline to facilitate an initial PubMed database search for all available full-text, peer-reviewed publications in English. Papers were screened for relevance to pregnant patients with hydrocephalus receiving acetazolamide therapy, as well as relevant papers describing related disorders of cerebrospinal fluid flow.

Results

There exist no prospective, randomised-controlled trials for the use of acetazolamide to treat hydrocephalus in pregnancy. Retrospective data in patients with related conditions suggest no significant link between acetazolamide use and teratogenicity in humans.

Conclusions

Acetazolamide can be a safe and efficacious therapy in the pregnant patient with refractory hydrocephalus as a bridge to delivery. We agree with the consensus and its appropriate use in the pregnant neurosurgical patient.