Wenyin Loh

Allergic rhinitis and non-allergic rhinitis in children in the tropics: prevalence and risk associations.

The age‐related comparative prevalence of allergic rhinitis (AR) and non‐allergic rhinitis (NAR) in children is poorly defined. We aimed to characterize AR and NAR in children.

A stepwise approach in the management of chronic spontaneous urticaria in children

Background There is limited literature in the management of chronic urticaria in children. Treatment algorithms are generally extrapolated from adult studies. Objective Utility of a weight and age-based algorithm for antihistamines in management of chronic spontaneous urticaria (CSU) in childhood. To document associated factors that predict for step of control of CSU and time taken to attain control of symptoms in children. Methods A workgroup comprising of allergists, nurses, and pharmacists convened to develop a stepwise treatment algorithm in management of children with CSU. Sequential patients presenting to the paediatric allergy service with CSU were included in this observational, prospective study. Results Ninety-eight patients were recruited from September 2012 to September 2013. Majority were male, Chinese with median age 4 years 7 months. A third of patients with CSU had a family history of acute urticaria. Ten point two percent had previously resolved CSU, 25.5% had associated angioedema, and 53.1% had a history of atopy. A total of 96.9% of patients achieved control of symptoms, of which 91.8% achieved control with cetirizine. Fifty percent of all the patients were controlled on step 2 or higher. Forty-seven point eight percent of those on step 2 or higher were between 2 to 6 years of age compared to 32.6% and 19.6% who were 6 years and older and lesser than 2 years of age respectively. Eighty percent of those with previously resolved CSU required an increase to step 2 and above to achieve chronic urticaria control. Conclusion We propose a weight- and age-based titration algorithm for different antihistamines for CSU in children using a stepwise approach to achieve control. This algorithm may improve the management and safety profile for paediatric CSU patients and allow for review in a more systematic manner for physicians dealing with CSU in children.

Tolerance to etoricoxib in children with nonsteroidal anti-inflammatory drug hypersensitivity

Background Cyclooxygenase-2 (COX-2) inhibitors have been found to be safe alternatives in adults with cross-intolerant hypersensitivity to nonsteroidal anti-inflammatory drugs (NSAIDs). However they are usually not prescribed in children and there is little information about their tolerance in the pediatric age group. Objective This study aims to evaluate the tolerance to etoricoxib in children with hypersensitivity to multiple antipyretics. Methods A retrospective case series of children diagnosed with hypersensitivity reactions to NSAIDs and/or paracetamol who underwent a drug provocation test (DPT) with etoricoxib. Information on atopy, family history of allergic diseases, and medication usage was collected. Outcomes of the DPTs and tolerance to etoricoxib were also evaluated. Results A total of 24 children, mean age 13.5 years, had a diagnosis of cross-intolerant hypersensitivity to NSAIDs and/or paracetamol. All except one patient successfully tolerated an oral challenge with etoricoxib. Of those who passed the DPT, the majority continued to use etoricoxib with no problems. It was found to be moderately effective in reducing fever and pain. Conclusion Etoricoxib can be used as a safe alternative in older children with hypersensitivity to multiple antipyretics.

Pilot study of the use of Yin Qiao San in children with conventional antipyretic hypersensitivity

Background Children with a diagnosis of cross-reactive hypersensitivity to both paracetamol and nonsteroidal anti-inflammatory drugs are limited in their choice of antipyretics. Objective The aim of this pilot study is to evaluate the feasibility of using a Chinese proprietary medicine, Yin Qiao San (YQS), for fever relief. Methods A single centre, open label, prospective clinical trial exploring the tolerability and feasibility of using YQS for fever relief in children who are unable to use conventional antipyretic medications. Children between 1-18 years of age with hypersensitivity to multiple antipyretics were recruited. Eligible participants underwent an oral provocation test with YQS. Children who passed the oral provocation test were instructed to take a prescribed dose of YQS when the temperature was >38.0℃ and continued till the fever settled. Time taken for fever resolution and any adverse events were collected. Results A total of 21 children, mean age 10.7 years, had a diagnosis of paracetamol and ibuprofen hypersensitivity. All except one patient successfully tolerated an oral challenge of YQS. Of the 88 doses of YQS taken for fever over 38.0℃, 16 (18%) had documented temperature reduction 2 hours after ingestion and 30 (34%) had documented temperature reduction 4 hours after ingestion. There were 2 reports of urticaria after YQS use which were attributed to flare of recurrent spontaneous urticaria during the illness. None of the patients developed symptoms of circulatory compromise or respiratory distress. Conclusion YQS is generally well tolerated in patients with paracetamol and ibuprofen hypersensitivity.

An unusual case of infant seizures with anaphylaxis to wheat

Wheat allergy is one of the commonest food allergies in childhood and it typically presents with IgE mediated reactions, including anaphylaxis. Seizures are not typically reported to be a direct manifestation of anaphylaxis, though it can occur secondary to hypoxia following significant haemodynamic compromise. We describe a case of a previously well infant, who presented with anaphylactic shock to wheat and responded well to the initial management, but subsequently developed a cluster of brief generalised tonic clonic seizures without any ongoing haemodynamic instability. The tryptase level that was performed at 4–5 hours post reaction was raised at 49.1 µg/L. Skin prick test to wheat, wheat specific IgE, the omega-5 gliadin IgE were positive. Extensive work-up was performed to look for an underlying cause of seizures and all returned negative. To our knowledge, this is the first case report describing an unusual presentation of multiple seizures in a young infant, in association with an anaphylactic episode. In the absence of any other seizure provoking factor and underlying cause, we believe the association is more likely causative than coincidental.

Cashew nut allergy in Singaporean children

Background There has been an increasing trend of nut allergies in Singapore. Objective The aim of this study was to review the clinical characteristics of children with cashew nut allergy. Methods A retrospective analysis was conducted in a tertiary paediatric referral centre in Singapore from 2008 to 2015. A total of 99 subjects with positive specific IgE (≥0.35 IU/L) to cashew nut were identified. Clinical features including demographics, clinical reaction to cashew nut, associations with other nuts and test specific measurements were recorded. Results The results showed that cutaneous symptoms (71.2%) were the most common allergic manifestations. Anaphylaxis occurred in 3.8% of children. In addition, all cashew nut allergic subjects were cross-reactive (either sensitized or allergic) to pistachio. Cross-reactivity rate with peanuts was 53.8%. There was a strong prevalence of atopy among cashew nut allergic subjects. Conclusion In conclusion, cashew nut allergy is a significant tree nut allergy in Singapore.

Cause and Clinical Presentation of Anaphylaxis in Singapore: From Infancy to Old Age

Background: The study objective was to compare age-related differences in the cause and clinical presentation of anaphylaxis. Methods: We conducted a prospective study of patients visiting the emergency department for anaphylaxis. Data were collected from 3 emergency departments from 1 April 2014 to 31 December 2015. Patient electronic records with the diagnoses of allergy, angioedema, urticaria, and anaphylaxis (ICD-9 codes 9953, 9951, 7080, 9950, 7089) were screened and cases fulfilling World Allergy Organisation criteria for anaphylaxis were included. Results: A total of 426 cases of anaphylaxis were identified with a median age of 23 years (range 3 months to 88 years and 9 months). The causes of anaphylaxis were food (n = 236, 55%), drugs (n = 85, 20%), idiopathic (n = 64, 15%), and insect bites or stings (n = 28, 7%). The most common food was shellfish (n = 58, 14%) and the most common drugs were non-steroidal anti-inflammatory drugs (n = 26, 6%). There were more cases of food anaphylaxis in children than in adults (72 vs. 42%, p < 0.001) and more cases of drug anaphylaxis in adults than in children (28 vs. 10%, p < 0.001). Compared to patients of other ages, infants and young children had more gastrointestinal symptoms (adjusted odds ratio [aOR] 2.1, 95% CI 1.1-3.9), while schoolchildren and adolescents had more respiratory symptoms (aOR 2.7, 95% CI 1.4-5.2). Adults had more cardiovascular symptoms (aOR 2.9, 95% CI 1.8-4.6) and hypotension (aOR 3.7, 95% CI 2.1-6.8) compared to children. However, 42% of the infants lacked blood pressure measurements. Conclusions: Knowledge of age-related variation in the cause and clinical presentation of anaphylaxis aids in diagnosis and acute management.

Absence of esophageal eosinophilia in a toddler with severe eosinophilic esophagitis

Eosinophilic esophagitis (EoE) is a clinicopathologic disease characterised by esophageal dysfunction and eosinophil-predominant inflammation. Diagnosing EoE in children is particularly challenging as they tend to present with nonspecific symptoms and their mucosal specimens may have less than the threshold number of eosinophils. Reluctance to subject children to multiple endoscopic procedures and anesthesia often results in treatment with a proton pump inhibitor (PPI) first to evaluate clinical response. This approach presents a problem as a diagnosis of EoE may be missed. Here we present a case of a child with severe EoE whose initial biopsy did not show esophageal eosinophilia but progressed on to advance dis ease despite clinical response to PPI therapy.