Pantipa Chatchatee

Epidemiology and prophylaxis of viral hepatitis: a global perspective.

Viral hepatitis with various forms of acute and chronic liver disease as potential and ultimately fatal sequelae presents a public health problem worldwide.

Food hypersensitivity in two groups of children and young adults with atopic dermatitis evaluated a decade apart.

There is an impression that children today are experiencing allergic reactions to an increasing variety of foods. We compared two separate groups of children and young adults with atopic dermatitis evaluated a decade apart and found no difference in sensitization rates or overall clinical reactivity to a variety of foods. Allergies to egg, milk, wheat, soy, peanut, tree nuts, and seafood continue to account for ≈ 90% of food‐allergic reactions over the past decade.

Declining trend in the seroprevalence of infection with hepatitis A virus in Thailand

Abstract Since the mid 1970s, infection with hepatitis A virus (HAV) in Thailand has shifted from hyper-endemic to mesoendemic. In 2004, to explore this trend in prevalence further, 3997 subjects from four geographically distinct provinces of Thailand were tested, in a commercial ELISA, for antibodies to HAV. The results indicate that the seroprevalence of HAV continues to fall, almost certainly because the profound socio–economic development that has occurred over the last few decades in Thailand has brought with it significant improvements in sanitation and personal hygiene. As exposure to HAV declines, however, the risks of symptomatic and potentially severe infection in adulthood (rather than asymptomatic infection during childhood) and of epidemics of such infection, which would lead to profound economic loss, increases. Improvements in hygiene and sanitation to reduce exposure to the virus and measures to reduce the incidence of symptomatic disease in those infected, such as vaccination (which may only be cost-effective when targeted at high-risk groups), need to be carefully considered.

A Population-Based Study of Fish Allergy in the Philippines, Singapore and Thailand

Background: Fish allergy is the third most common food allergy after milk and egg in parts of Europe, but there is little data about prevalence in South East Asia where it is an important part of regular diets. Objective: We aimed to obtain an estimate of the population prevalence of fish allergy among older children in the Philippines, Singapore and Thailand. Methods: The population prevalence of fish allergy in 14- to 16-year-old children in the 3 countries was evaluated using a structured written questionnaire which was distributed to students of randomly selected secondary schools. An extended questionnaire to determine convincing fish allergy on the basis of typical clinical manifestations within 2 h of ingestion was administered to those with positive responses. Results: From acohort of 25,842 students, responses were 81.1% in the Philippines (n = 11,434), 67.9% in Singapore (n = 6,498) and 80.2% (n = 2,034) in Thailand. Using criteria for convincing food allergy, fish allergy was much higher in the Philippines [2.29%, 95% confidence interval (CI) 2.02–2.56] than in Singapore (0.26%, 95% CI 0.14–0.79) and Thailand (0.29%, 95% CI 0.06–0.52). Weighted multiple logistic regression analyses showed that compared to the Philippines, prevalence rates were lower in Singapore [odds ratio (OR) 0.40, 95% CI 0.27–0.60, p < 0.0001] and Thailand (OR 0.13, 95% CI 0.05–0.33, p < 0.0001). Females were more likely to have fish allergy compared to males for all children combined (OR 1.32, 95% CI 1.11–1.58, p = 0.002). Most allergies appeared mild, as only 28% of cases sought medical consultation at the time of the reaction and 31.2% of cases reported continued exposure despite allergic symptoms. Conclusion: Fish allergy in late childhood is more common in the Philippines compared to Singapore and Thailand. Differences in food processing, dietary habits and other cultural practices might be important risk factors for the development of fish allergy in these populations.

Molecular characterization of hepatitis-A-virus infections, in the context of two outbreaks in southern Thailand

Abstract As hepatitis A virus (HAV) is usually transmitted through the faecal-oral route, hepatitis A is a communicable disease. In countries of intermediate to low endemicity, sudden outbreaks of human infection with the virus may occur. Between September 2001 and April 2002, there were two outbreaks of HAV infection in the Ruso and Yeengor districts of Narathiwas province, in southern Thailand. Isolates of HAV were recovered during these outbreaks, from 14 in-patients with acute hepatitis in Ruso (12 positive for anti-HAV IgM and all positive for HAV RNA), 16 children with asymptomatic infection in Yeengor (14 positive for anti-HAV IgM and nine for HAV RNA), and four isolated cases in Bangkok (all positive for anti-HAV IgM). Molecular characterization of the VP1-P2A region of each isolate was followed by phylogenetic analysis. All of the isolates from Narathiwas province were found to be of genotype 1a, to have the same VP1 nucleotide sequence, and to show a high level of sequence homology (≥ 99.5%) with the isolates from Bangkok and with previous Thai isolates. These results should facilitate further research into HAV transmission and genotype identification in community outbreaks.

Component-resolved diagnostics for the evaluation of peanut allergy in a low-prevalence area.

Major allergenic components of peanut from distinct geographical regions are widely dispersed. Most of the diagnostic studies are from countries with a high prevalence. There have been only few reports of allergen component sensitizations from countries with a low prevalence of peanut allergy. We aimed to investigate roles of component‐resolved diagnostic (CRD) to differentiate peanut allergy and peanut tolerance in the Asian population from a country with low prevalence of peanut allergy.

The House Dust Mite Major Allergen Der p 23 Displays O-Glycan-Independent IgE Reactivities but No Chitin-Binding Activity.

Background: The in-depth characterization of the recently identified house dust mite (HDM) major allergen Der p 23 requires the production of its recombinant counterpart because the natural allergen is poorly extractable from fecal pellets. This study aimed to provide a detailed physico-chemical characterization of recombinant Der p 23 (rDer p 23) as well as to investigate its IgE reactivity in a cohort of HDM-allergic patients from Thailand. Methods: Purified rDer p 23, secreted from recombinant Pichia pastoris, was characterized by mass spectrometry and circular dichroism analyses as well as for its chitin-binding activity. The IgE-binding frequency and allergenicity of Der p 23 were determined by ELISA and RBL-SX38 degranulation assays, respectively. Results: Purified intact rDer p 23 carried O-mannosylation and mainly adopted a random coil structure. Polyclonal antibodies to rDer p 23 can detect the corresponding natural allergen (nDer p 23) in aqueous fecal pellet extracts, suggesting that both forms of Der p 23 share common B-cell epitopes. Despite its homologies with chitin-binding proteins, both natural Der p 23 and rDer p 23 were unable to interact in vitro with chitin matrices. Of 222 Thai HDM-allergic patients tested, 54% displayed Der p 23-specific IgE responses. Finally, the allergenicity of rDer p 23 was confirmed by the degranulation of rat basophil leukemia cells. Conclusion: Our findings highlighted important levels of Der p 23 sensitizations in Thailand. Our study clearly suggested that rDer p 23 is likely more appropriate for HDM allergy component-resolved diagnosis than HDM extracts.

Disseminated cytomegalovirus infection associated with Pneumocystis carinii pneumonia in a previously normal infant.

We reported a rare case of dual opportunistic infections of Pneumocystis carinii pneumonia and disseminated cytomegalovirus (CMV) infection in a previously normal female infant. Transient T-cell dysfunction was demonstrated and returned to normal after treatment of CMV infection.

The natural course of childhood atopic dermatitis: a retrospective cohort study.

BACKGROUND Atopic dermatitis (AD) is generally considered to be the initial step of the so-called atopic march, which following steps are allergic rhinitis (AR) and asthma. There are few data about the progression of AD, including factors associated with the remission of AD in Asians and further research is needed. OBJECTIVE To study the progression and factors associated with the remission of childhood AD diagnosed by pediatric dermatologists. METHODS This study included 303 AD patients who visited the pediatric dermatology unit at King Chulalongkorn Memorial Hospital, Thailand, between 2002 and 2010. An interview, performed by a physician via telephone using a preformed questionnaire, was completed for 205 children. RESULTS A total of 205 children were observed, with a median observation time of 5.2 (3.5-8.0) years, and an initial AD severity score of mild (61.0%), moderate (29.3%) and severe (9.7%). The prevalence of AD during the first two years of life was 64.4%. AD completely disappeared in 102 cases (49.8%) by the median age of 3.5 (1.5-7.8) years. Early onset and severity of AD were major determinant of prognosis. The prevalence of AR and asthma was 36.6%, and 9.3%, respectively. The risk factors associated with respiratory allergy were the onset of AD after aged two years, a family history of atopy, increased serum IgE level, and sensitization to inhalant allergens. CONCLUSIONS Half of AD had completely disappeared at preschool age. Good prognosis was mostly determined by early onset AD and mild severity. Late onset, family history of atopy and increased serum IgE level are associated with respiratory allergy.

Recurrent purpura fulminans associated with drug-resistant Streptococcus pneumoniae infection in an asplenic girl.

We report a case of purpura fulminans associated with drug-resistant Streptococcus pneumoniae that responded to ceftriaxone therapy. Ultrasonography of the abdomen and splenic scan revealed the absence of a spleen.