Predictors of Clinical Outcomes in Acute Appendicitis: A Retrospective Study

INTRODUCTION

Acute appendicitis is one of the most common causes of intra-abdominal emergency surgery worldwide. This study was conducted to contribute to global databases by presenting data from our institution, which consist of multi-racial population. We aimed to evaluate the presentation, diagnosis, and management of acute appendicitis and post-operative outcome in our institution and evaluate the risks factors associated with severe complications and prolonged length of stay (LOS).

MATERIALS AND METHODS

We performed a retrospective analysis using multivariate regression analysis of all patients who underwent appendectomy (2009-2014) in our institution. The primary outcomes included demographics, presentation, and perioperative management, and the secondary outcomes included risk factors associated with prolonged LOS.

RESULTS

Of the 1185 patients, the mean age was 36.4 years, and 940 (79.3%) were male. Majority (98.1%) of patients were ASA (American Society of Anaesthesiologists) 1 or 2. Most of them (83.9%) were from the four racial subgroups (Chinese, Malay, Bangladeshi, and Indian). There was no racial variation in the diagnosis and presentation of disease. The mean duration of symptoms was 1.8 days. The history was commonly a localised or migratory abdominal pain associated with anorexia, nausea, vomiting, and fever. The commonest physical findings were right-sided abdominal tenderness associated with rebound and guarding. About 42.9% of the patients underwent pre-operative CT scan to establish the diagnosis of appendicitis prior to surgery, whilst 57.1% underwent surgery on clinical diagnosis and blood investigation (NWR and CRP). An open appendectomy was performed in 13.2% of the patients. The conversion rate of laparoscopic appendectomy was 4.9% (n = 50). The mean length of hospital stay was 3.6 days. On multivariate Cox regression, patients of Burmese and Thai descent were independently associated with a prolonged LOS. The postoperative morbidity was 5.5%. The 30-day readmission rate was 2.4%. There was no mortality in our study.

DISCUSSION

Our study showed that pre-operative diagnosis of acute appendicitis can be made accurately by classical clinical presentation or by imaging. Independent risk factors associated with increased LOS included increased age, male gender, prolonged duration of symptoms pre-admission, fever, generalised tenderness, and prolonged operative time. The effect of race on LOS has been observed in the literature for other surgical procedures. The prolonged LOS found in Burmese and Thai patients contribute to the possibility of intrinsic racial differences in the post-surgery recovery. However, the numbers are small and therefore prone to type I error. Compared to the open approach, the use of laparoscopic appendectomy was associated with shorter LOS. This has similar outcomes to those reported in the literature.

CONCLUSION

The identification of risks factors could help surgical team to predict the clinical outcomes and develop risk reduction strategy in post-operative care of these patients.

High Prevalence of Late-Onset Fabry Cardiomyopathy in a Cohort of 499 Non-Selective Patients with Left Ventricular Hypertrophy: The Asian Fabry Cardiomyopathy High-Risk Screening Study (ASIAN-FAME)

Left ventricular hypertrophy (LVH) caused by cardiac variant Fabry disease (FD) is typically late-onset and may mimic LVH caused by abnormal loading conditions. We aimed to determine the prevalence of FD in a non-selective patient population of everyday practice presenting with LVH, including those with hypertension and valve disease. We measured plasma alpha-galactosidase A activity using dried blood spot tests in 499 (age = 66 ± 13 years; 336 men) Hong Kong Chinese patients with LVH defined as maximal LV septal/posterior wall thickness ≥13 mm on echocardiography. Patients with low enzyme activity underwent mutation analysis of the GLA gene. Eight (age = 53−74 years; all men) unrelated patients (1.6%) had low plasma alpha-galactosidase A activity (0.57 ± 0.27 μmol/L wb/hr) and all were confirmed to have the GLA IVS4 + 919G > A mutation. FD patients presented with heart failure (n = 5), heart block (n = 2), ventricular tachycardia (n = 1), chest pain (n = 3), and/or murmur (n = 1). Uncontrolled hypertension (n = 4) and/or severe mitral/aortic valve pathology (n = 2) were frequent. Ethnic subgroups included Teochew (n = 5), Canton (n = 2), and Wenzhou (n = 1). Endomyocardial biopsy (n = 6) revealed hypertrophic myocytes with vacuolization and dense lamellar bodies. Late-onset IVS4 + 919G > A FD is prevalent among Chinese LVH patients, and should be considered as a cause of LVH in adult patients even when hypertension and/or valve pathology are present.

Screening for Fabry Disease in patients with unexplained left ventricular hypertrophy

Fabry Disease (FD) is a systemic disorder that can result in cardiovascular, renal, and neurovascular disease leading to reduced life expectancy. FD should be considered in the differential of all patients with unexplained left ventricular hypertrophy (LVH). We therefore performed a prospective screening study in Edmonton and Hong Kong using Dried Blood Spot (DBS) testing on patients with undiagnosed LVH. Participants found to have unexplained LVH on echocardiography were invited to participate and subsequently subjected to DBS testing. DBS testing was used to measure α-galactosidase (α-GAL) enzyme activity and for mutation analysis of the α-galactosidase (GLA) gene, both of which are required to make a diagnosis of FD. DBS testing was performed as a screening tool on patients (n = 266) in Edmonton and Hong Kong, allowing for detection of five patients with FD (2% prevalence of FD) and one patient with hydroxychloroquine-induced phenocopy. Left ventricular mass index (LVMI) by GLA genotype showed a higher LVMI in patients with IVS4 + 919G > A mutations compared to those without the mutation. Two patients were initiated on ERT and hydroxychloroquine was discontinued in the patient with a phenocopy of FD. Overall, we detected FD in 2% of our screening cohort using DBS testing as an effective and easy to administer screening tool in patients with unexplained LVH. Utilizing DBS testing to screen for FD in patients with otherwise undiagnosed LVH is clinically important due to the availability of effective therapies and the value of cascade screening in extended families.

CHARGE syndrome in nine patients from China

CHARGE syndrome (CS) is a multiple congenital anomalies condition with the majority of cases caused by dominant loss-of-function mutations of the CHD7 gene. It is clinically characterized by coloboma of the eyes, heart defects, choanal atresia, retardation of growth and/or development, genital and/or urinary anomalies and ear malformations associated with deafness and vestibular disorder(s). This case series reported nine molecularly confirmed Chinese CS patients from nine unrelated families in Hong Kong. Clinical phenotype and facial features of these nine Chinese CS patients together with four previously reported Chinese patients were reviewed. Typical presentations like coloboma and choanal atresia were not universally present. The prevalence of choanal atresia in these Chinese CS patients was found to be significantly lower than that in previous cohorts of other ethnic groups. This report highlighted the existence of phenotypic variation of CS among different ethnicities and suggested that a high index of suspicion is necessary for diagnosis of CS in Chinese patients.

Genetic landscape of RASopathies in Chinese: Three decades' experience in Hong Kong

RASopathies are a group of genetic disorders due to dysregulation of the RAS-MAPK signaling pathway, which is important in regulating cell growth, proliferation, and differentiation. These include Noonan syndrome (NS), Noonan syndrome with multiple lentigines (NSML), cardiofaciocutaneous (CFC) syndrome, and Costello syndrome (CS), clinical manifestations include growth retardation, developmental delay, cardiac defects, and specific dysmorphic features. There were abundant publications describing the genotype and phenotype from the Western populations. However, detailed study of RASopathies in Chinese population is lacking. We present here the largest cohort of RASopathies ever reported in Chinese populations, detailing the mutation spectrum and clinical phenotypes of these patients. The Clinical Genetic Service, Department of Health, and Queen Mary Hospital are tertiary referral centers for genetic disorders in Hong Kong. We retrospectively reviewed all the genetically confirmed cases of RASopathies, including NS, NSML, CFC syndrome, and CS, over the past 29 years (from 1989 to 2017). Analyses of the mutation spectrum and clinical phenotypes were performed. One hundred and ninety-one ethnic Chinese patients with genetically confirmed RASopathies were identified, including 148 patients with NS, 23 NSML, 12 CFC syndrome, and eight CS. We found a lower incidence of hypertrophic cardiomyopathy in individuals with NSML (27.3%), and NS caused by RAF1 mutations (62.5%). Another significant finding was for those NS patients with myeloproliferative disorder, the mutations fall within Exon 3 of PTPN11 but not only restricted to the well-known hotspots, that is, p.Asp61 and p.Thr731, which suggested that re-evaluation of the current tumor surveillance recommendation maybe warranted.