Birdshot Retinochoroidopathy: Differences in Clinical Characteristics between Patients with Early and Late Age of Onset

Purpose: To describe differences in the clinical characteristics of birdshot retinochoroidopathy (BSRC) patients diagnosed early and later in life.

Methods: This is a retrospective cohort study. Age was primarily analyzed and 50 years of age at diagnosis was selected as a cut-off point.

Results: A total of 144 patients (288 eyes) were included; 68 with early-onset and 76 with late-onset BSRC. The younger group had a statistically significant higher rate of more severe iritis (p = 0.04); an average number of non-steroidal immunosuppressants and biologic agents (NSIB) (p = 0.04); and a prolonged time to initiation of NSIB (p = 0.01). There were only four patients (3%) who had >0.5+ cells in the anterior chamber.

Conclusions: Patients with early-onset BSRC carried a higher risk for anterior segment inflammation, had a more prolonged delay to initiation of treatment with NSIB, and required a greater number of NSIBs to achieve remission.     

Persistence of antibodies and immune memory to hepatitis B vaccine 20 years after infant vaccination in Thailand

Booster vaccination against hepatitis B (HBV) is not currently recommended, although debate continues on the duration of protection after priming. We assessed antibody persistence and immune memory to hepatitis B 20 years after priming with a recombinant HBV-vaccine during infancy. Infants were vaccinated at birth, 1, 2 and 12 months of age. A subset received a booster dose at Year 5. Antibody persistence was measured approximately yearly until Year 20. Immune memory was assessed by administration of HBV booster dose. At Year 20, anti-HBs seroprotection rates and GMCs tended to be higher in Year 5 boosted than unboosted recipients (83.9% versus 60.5%). After the Year 20 booster dose, anti-HBs anamnestic responses were within the same range 95.8% of subjects in both groups. Primary and booster vaccination with HBV-vaccine in infants induces sustained seroprotection and immune memory against hepatitis B for up to 20 years. Higher persisting seroprotection rates in subjects boosted at Year 5 did not translate into apparent differences in immune memory in a high endemic country.     

Rapid detection of lamivudine-resistant hepatitis B virus mutations by PCR-based methods

Hepatitis B virus (HBV) is one of the major causes of liver disease worldwide, and chronic HBV infection may progress to cirrhosis and hepatocellular carcinoma. Mutations at the active site of DNA polymerase of HBV, tyrosine-methionine-aspartate-aspartate (YMDD) motif, render infected patients resistant to antiviral drug (Lamivudine) therapy. Hence, sensitive and specific methods aimed at detecting the mutants are essential. The purpose of this study was to develop methods for detecting the mutations at YMDD by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and real-time PCR using locked nucleic acid (LNA)-mediated TaqMan probes. The results obtained by these methods were compared with those examined by conventional direct sequencing on serum samples of 77 patients treated with lamivudine. Our results show that both PCR-RFLP and real-time PCR could detect wild type, YMDD, and its mutants, tyrosine-isoleucine-aspartate-aspartate and tyrosine-valine-aspartate-aspartate. In addition, the mixtures of the wild-type virus and its mutants in the serum sample were detected. Importantly, real-time PCR is less time-consuming, and more sensitive for the detection of mixed populations than PCR-RFLP. The real-time PCR with LNA-mediated TaqMan probes is a sensitive, specific and rapid detection method for mutations at the YMDD motif, which will be essential for monitoring patients undergoing lamivudine antiviral therapy.     

Acute urticaria: etiologies, clinical course and quality of life

One hundred patients with acute urticaria were prospectively studied over a 2-year period with respect to etiology, clinical features and outcome, including the patient's quality of life using a Thai version of the Dermatologic Life Quality Index (DLQI). Twenty-one patients (21%) turned out to have chronic and 79 acute urticaria. Itchy sensations had the highest mean DLQI score translating to the highest negative impact on the quality of life. In more than half of the patients, the cause of the acute urticaria could not be identified. The most common identified causes of acute urticaria were infections (36.7%), followed by drugs, foods and insect bite reactions. Among those with acute urticaria, sixteen percent had co-existing angioedema, and one fourth had systemic symptoms, the most common being dyspnea. Patients with extensive wheals tended to have co-existing angioedema and also a statistically significant higher percentage of systemic symptoms, higher mean pruritus and mean DLQI scores than those with less body surface area involvement. Fifty-six percent of the patients with acute urticaria had complete remissions within 1 week; 78.5%, within 2 weeks and 91.1%, within 3 weeks.     

Molecular characterization and phylogenetic analysis of H1N1 and H3N2 human influenza A viruses among infants and children in Thailand

The annual influenza outbreaks can cause a high mortality rate among infants and children. In the tropics, influenza shows no clear dependence on seasons. In the present study, we performed molecular and phylogenetic analysis of H1N1 and H3N2 influenza virus isolated from infants and children diagnosed with respiratory tract illness between February 2006 and February 2007. A total of 33 samples (10.92%) were found positive for human influenza virus infection. Characterization of the hemagglutinin gene revealed conserved sequences at the receptor-binding site as well as variations due to amino acid substitutions at the antigenic site, potentially resulting in an N-linked glycosylation site. As for the neuraminidase gene, amino acid substitutions were found in N1 and N2 but not directly at the catalytic or framework sites of this enzyme. Based on the phylogenetic tree, the hemagglutinin 1 (HA1) region and the neuraminidase (NA) gene of both H1N1 and H3N2 isolated subtypes clustered with the current vaccine strain for the Northern Hemisphere 2007-2008. This finding contributes to understanding the evolution of influenza A viruses in humans and is useful for surveillance and vaccine strain selection.     

Declining hepatitis A seroprevalence among medical students in Bangkok,Thailand, 1981-2001

The severity of clinical symptoms following hepatitis A virus (HAV) infection is age dependent. Hepatitis A in children is mostly an asymptomatic disease while adolescents and adults usually show symptoms of clinical hepatitis. Improved personal hygiene and environmental sanitation has led to a decline in natural immunity acquired in childhood, creating a population of susceptible adults. In the past decade, the incidence and prevalence of hepatitis A disease in Thailand have decreased significantly. In this study, we used enzyme-linked immunosorbent assay to determine the prevalence of anti-HAV antibodies among medical students at two different time points in 1996 and 2001. We then compared these results with data from previous studies in 1981 and 1992. The seroprevalence was 73.01%, 30.23%, 16.67% and 6.67% in 1981, 1992, 1996 and 2001, respectively. A significant decline has happened over the past two decades (p < 0.001). Considering the decreasing immunity to HAV in the younger generations, more cases of symptomatic HAV infection could be anticipated. Further seroprevalence studies in other adolescence groups from different socioeconomic status are needed to elucidate the current situation of HAV infection in the young generation more comprehensively and to develop an appropriate prevention program.     

Regional abdominal fat distribution in lean and obese Thai type 2 diabetic women: relationships with insulin sensitivity and cardiovascular risk factors

To determine the relationships of body fat distribution and insulin sensitivity and cardiovascular risk factors in lean and obese Thai type 2 diabetic women, 9 lean and 11 obese subjects, with respective mean age 41.7 +/- 6.3 (SD) and 48.0 +/- 8.5 years, and mean body mass index (BMI) 23.5 +/- 1.8 and 30.3 +/- 3.7 kg/m2, were studied. The amount of total body fat (TBF) and total abdominal fat (AF) were measured by dual-energy x-ray absorptiometer, whereas subcutaneous (SAF) and visceral abdominal fat areas (VAF) were measured by computerized tomography (CT) of the abdomen at the L4-L5 level. Insulin sensitivity was determined by euglycemic hyperinsulinemic clamp. Cardiovascular risk factors, which included fasting and post-glucose challenged plasma glucose and insulin, systolic (SBP) and diastolic blood pressure (DBP), lipid profile, fibrinogen, and uric acid, were also determined. VAF was inversely correlated with insulin sensitivity as determined by glucose infusion rate (GIR) during the clamp, in both lean (r=-0.8821; P=.009) and obese subjects (r=-0.582; P=.078) independent of percent TBF. SAF and TBF were not correlated with GIR. With regards to cardiovascular risk factors, VAF was correlated with SBP (r=0.5279; P=.024) and DBP (r=0.6492; P=.004), fasting insulin (r=0.7256; P=.001) and uric acid (r=0.4963; P=.036) after adjustment for percent TBF. In contrast, TBF was correlated with fasting insulin (r=0.517; P=.023), area under the curve (AUC) of insulin (r=0.625; P=.004), triglyceride (TG) (r=0.668; P=.002), and uric acid (r=0.49; P=.033). GIR was not correlated with any of cardiovascular risk factors independent of VAF. In conclusion, VAF was a strong determinant of insulin sensitivity and several cardiovascular risk factors in both lean and obese Thai type 2 diabetic women.     

Long-Term Outcomes and Sites of Failure in Locally Advanced,Cervical Cancer Patients Treated by Concurrent Chemoradiation with or without Adjuvant Chemotherapy: ACTLACC Trial

Objectives: To evaluate sites of failure and long-term survival outcomes of locally advanced stage cervical cancer patients who had standard concurrent chemo-radiation (CCRT) versus those along with adjuvant chemotherapy (ACT) after CCRT. Methods: Patients aged 18–70 years who had FIGO stage IIB-IVA without para-aortic lymph node enlargement (excluding by International Federation of Gynecology and Obstetrics (FIGO) 2018 stage IIIC2r), The Eastern Cooperative Oncology Group (ECOG) scores 0–2, and non-aggressive histopathology were randomized to have CCRT with weekly cisplatin followed by observation (arm A) or ACT with paclitaxel plus carboplatin every 4 weeks for 3 cycles (arm B). Results: From 2015-2017, 259 patients were evaluated. The majority of patients were in stage II and had squamous cell carcinoma with a median tumor size of 5 cm. After the median follow-up of 40.87 months, 17.1% of the patients in arm A and 12.3% of the patients in arm B experienced recurrences (p=0.280). Adding all events of failure (persistence/progression/recurrence), treatment failures tended to be lower in arm A than in arm B: 13.2 versus 21.5 % for loco-regional failure (p = 0.076) and 3.9 versus 6.9% for loco-regional failure and systemic failure (p = 0.278). On the other hand, systemic failure tended to be higher in arm A than in arm B: 13.2% versus 6.9% (p =0.094). The 5-year progression-free survival and 5-year overall survival of patients in both arms were not significantly different. Conclusions: ACT with paclitaxel plus carboplatin after CCRT did not improve response or survival of patients compared to CCRT alone. Although systemic failure tended to be lower in patients who had ACT after CCRT than those who had only CCRT, loco-regional failure with or without systemic failure tended to be higher. However, all of these differences were not statistically significant.     

Chronic idiopathic urticaria: prevalence and clinical course

The purpose of our study was to assess the prevalence and clinical course of patients with chronic idiopathic urticaria (CIU), as well as possible causes or associated findings, laboratory findings and the duration of the disease in patients with chronic urticaria (CU). We retrospectively reviewed the 450 case record forms of patients with CU and/or angioedema who attended the Department of Dermatology, Siriraj Hospital, during the period 2000-2004. Of 450 patients with CU, 337 patients (75%) were diagnosed as CIU. Forty-three patients (9.5%) had physical urticaria, while 17 patients (3.8%) had infectious causes. Other possible causes were food, thyroid diseases, atopy, drugs, dyspepsia and collagen vascular diseases. In eighty-nine percent of patients, no abnormalities were detected at the time of physical examination. The most common abnormal laboratory finding was minimal elevation of the erythrocyte sedimentary rate (42%). In 61 patients, autologous serum skin tests had been done. Fifteen patients (24.5%) had positive results i.e. autoimmune urticaria. Anti-thyroglobulin and anti-microsomal antibodies were positive in 16 % and 12% of CIU patients respectively. After 1 year from the onset of the symptoms, 34.5% of CIU patients were free of symptoms and after 1.2 years from the onset of the symptoms, 56.5% of autoimmune urticaria patients were free of symptoms. The median disease duration of CIU and autoimmune urticaria were 390 days and 450 days respectively. Our study provided an overview of CU and CIU in a large series of Thai patients, based on etiological aspects and clinical courses.