Abhilash Balakrishnan

Aeroallergen sensitization in pediatric allergic rhinitis in Singapore: Is air-conditioning a factor in the tropics?

Singapore is a unique blend of a tropical environment with a high standard of hygiene and public health care. The objective was to define the prevalence, clinical characteristics, and environmental risk factors of specific aeroallergen sensitization in pediatric allergic rhinitis patients in this unique environment. The method adopted was a retrospective analysis of allergic rhinitis patients, undergoing aeroallergen skin prick testing (SPT), in the outpatient specialty clinic of the KK Childrens hospital, from July 2001 to June 2002. A total of 202 patients were included, 161 (80%) males, 167 (83%) Chinese, age mean 7.6 yr (range 2–14 yr). The most prevalent clinical symptoms were: watery rhinorrhea 61%, blocked nose 61%, sneezing 52%, snoring 17%, and epistaxis 12%. SPT results were positive for house dust mites in 97% of children, pets (20%), molds (19%), pollens (15%), and kapok (10%). Mold sensitization was significantly more prevalent in households without air‐conditioning (aircon), 49% vs. 10% with aircon (odds ratio 9.4, 95% CI 3.8–22.9). Polysensitization (sensitization to three or more allergens) was similarly more prevalent in households without aircon, 51% vs. 14% with aircon (odds ratio 6.4, 95% CI 2.8–14.7). It was concluded that indoor aeroallergen sensitization is the major associated factor with clinical allergic rhinitis in children in Singapore. Patients living in households without air‐conditioning are at increased risk of mold sensitization and polysensitization.

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.

Bimodal skin reactivity to histamine in atopic children in Singapore: influence of specific sensitizations

Histamine skin prick test (SPT) is used as the ‘golden standard’ for positive control in in vivo immediate type hypersensitivity testing. The skin reactivity to histamine can, however, be modulated by a bevy of extraneous factors. We aimed to define whether histamine skin reactivity in atopic children in Singapore is influenced by age, ethnic origin, gender, environmental exposure or specific sensitization patterns. A retrospective analysis of children, with specific aeroallergen sensitization (as measured by at least one allergen‐specific SPT with a wheal size >3 mm compared with the negative control) from the outpatient speciality clinic of the KK Childrens Hospital, during 06/2002–06/2003. A total of 315 patients were included, 235 (75%) were males, 252 (80%) were Chinese, age mean was 7.7 yr (range: 2–15). Patients were referred to the SPT with a diagnosis of one or more of: allergic rhinitis 287 (91%), asthma 112 (36%) or atopic dermatitis 60 (19%). The mean histamine response showed a bimodal distribution, independent of age, ethnic origin, gender or phenotypical expression of allergic disease. Histamine skin reactivity was higher in atopic patients with polysensitization (mean 5.0 mm vs. 2.9 mm in monosensitized patients, p < 0.001), and in patients with mould sensitization (mean 5.1 mm vs. 3.3 mm in patient not sensitized to moulds, p < 0.001). The presence of passive smoking increased the likelihood of a diminished histamine skin response. Histamine skin response data strongly suggested the presence of two heterogeneous subpopulations. Children with polysensitization and mould sensitization were more likely to show a large significant histamine response, whereas children with passive smoke exposure, showed a diminished skin reactivity to histamine.

Preauricular sinuses in the pediatric population: Techniques and recurrence rates

AIM To review the outcomes of two surgical techniques in the management of preauricular sinus in the pediatric population. METHODS The clinical records of pediatric patients who underwent surgical excision of preauricular sinus in the Department of Otolaryngology of KK Childrens and Womens Hospital between January 1997 and March 2009 were retrospectively reviewed. Patients were categorized into two groups, based on the method used for sinus tract visualization or delineation: (1) Microscope group and (2) methylene blue dye and probe group. The latest information on recurrence of preauricular sinus and complications after surgery were updated by phone interview. RESULTS 208 out of 305 preauricular sinuses were included in this study (n=114 in microscope group; n=94 in methylene blue dye and probe group). 97 cases were excluded as these patients were not contactable by phone or had inadequate data from the clinical records. The mean age of the patients is 6.5 years old. The overall recurrence rate was 2.4% (95% confidence interval (CI) 0.010-0.055) and the overall complication rate was 6.3% (CI 0.037-0.104). Surgical excision with microscope guidance had significantly lower recurrence rate (0.9%) compared to surgical excision with methylene blue dye and probe guidance (4.3%), with an odds ratio of 28.4 (CI 1.22-659.99, P=0.037). The complication rates were not statistically significant between the two groups. The recurrence and complication rates were not significantly affected by race, gender, sex, location of sinus, indication for surgery, history of previous sinus excision, presence of infection during surgery and duration of surgery. CONCLUSION Surgical excision of preauricular sinus under microscope guidance and under methylene blue and probe guidance in our series had very low overall recurrence and complication rates compared to that reported in the literature. The microscope group had a lower recurrence rate in comparison to that of the methylene blue and probe group.

Laryngeal inflammatory myofibroblastic tumor (IMT): a case report and review of the literature.

BackgroundThis case report is interesting as cases of children with laryngeal inflammatory myofibroblastic tumor are not common and previously had been presented as isolated case reports. This is the first case report in Asia describing a laryngeal inflammatory myofibroblastic tumor and its removal using an endoscopic approach.Case presentationOur patient is a 12-year-old Malay girl from Singapore who presented with hoarseness without respiratory distress. The initial impression was that of a granuloma or a papilloma. We did a biopsy, which confirmed the histology to be inflammatory myofibroblastic tumor, and a magnetic resonance imaging scan showed a contrast-enhanced lesion. The lesion was excised completely using an endoscopic approach. The child was discharged well on the first postoperative day and she has been on follow-up for a year in the clinic.ConclusionsThis report highlights the importance of understanding the differential diagnosis for a child with hoarseness. It is not uncommon for a pediatrician, a general practitioner, and a pediatric otolaryngologist to see a child presenting with hoarseness. In most cases, the diagnosis made would be screamer’s nodules, which is commonly seen in children. In a small group, recurrent respiratory papillomatosis form the diagnosis. Over the past few years, the cases of recurrent respiratory papillomatosis have decreased significantly. Laryngeal tumors are not common in children. However, we must maintain a high index of suspicion when we have a child with hoarseness who does not improve with speech therapy and watchful waiting. In such situations, a stroboscope is usually necessary to diagnose the voice problems and to rule out pathological conditions such as laryngeal tumors. If left untreated, the lesion can grow with time and result in a life-threatening airway condition. We also demonstrate our endoscopic technique in this report, and it has proven to be safe with no increased recurrence and much lower morbidity.

Postoperative Hemostasis Rate following Tonsillectomy at a Singapore Pediatric Tertiary Hospital

Objectives: Tonsillectomies and adenotonsillectomies are among the most common procedures to be carried out in children throughout the world. Postoperative hemorrhages have previously been reported to be at a maximum expected rate of 13.9% with a mean of 4.5%. This study reports the postoperative hemostasis rate at the KK Women’s and Children Hospital, Singapore, a tertiary pediatric hospital. Methods: Retrospective study of tonsillectomy and adenotonsillectomy cases done on children up to 16 years of age from the end of January 2007 till early January 2013. The number of postoperative bleeds that required return to the operating room for hemostasis was recorded. Results: In total there were 2322 tonsillectomy cases. 1581 were adenotonsillectomies, and 741 were bilateral tonsillectomies only (without adenoidectomy). There were 33 cases that required return to the operating room for hemostasis, giving a postoperative hemostasis rate of 1.42%. There were no cases of bleeding from adenoidectomy. All 2322 cases were done with monopolar diathermy. Hemostasis intraoperatively was also done with monopolar diathermy. The operating surgeons ranged from first year residents to senior consultants. Conclusions: The postoperative hemostasis rate following tonsillectomy and adenotonsillectomy at KK Women’s and Children’s Hospital is 1.42%, comparable to the best rates quoted in the literature .