HLA-A*24:02/B*51:01 haplotype and lamotrigine-induced cutaneous adverse drug reactions in Koreans

Antiepileptic drugs (AEDs) have been known to induce cutaneous adverse drug reaction (cADR), ranging from a mild maculopapular eruption (MPE) to potentially life-threatening cADRs such as Stevens–Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN). Despite studies examining mechanisms associated with human leukocyte antigen (HLA), the association between lamotrigine (LTG)-induced cADR and HLA alleles still has room to investigate. We investigated HLA-A,-B, and -C alleles in LTG-induced cADR. The medical records of four patients with LTG-induced cADR were retrospectively reviewed. All patients were treated with LTG for epilepsy. All recovered from cADR after stopping LTG treatment and receiving intensive care. HLA-A, -B, and -C genotyping was performed in all four patients using a PCR-sequence-based typing (SBT) method. Two patients had SJS, and the other two had MPE due to LTG. The range of latency to cADR after the initial LTG dose was 19–42 days. Two patients experienced cross-reactivity with other aromatic or new AEDs. Expression of the HLA-A*24:02/B*51:01 haplotype was detected in three (75%) patients with LTG-induced cADR. The other patient carried homozygous HLA-B*58:01 alleles. The results suggest that Korean individuals with the HLA-A*24:02/B*51:01 haplotype may be susceptible to LTG-induced cADR. Further investigations are necessary to confirm these findings.

Genetic polymorphisms of CYP2C9, CYP2C19, CYP2D6, CYP3A4, and CYP3A5 in Vietnamese-Koreans

The Vietnamese-Koreans, especially offspring between a Vietnamese mother and a Korean father constituted the highest proportion (64.2%) of total Kosian population according to a census in 2014. To evaluate genetic characteristics in the Vietnamese-Koreans, a total of 25 alleles from CYP2C9, CYP2C19, CYP2D6, CYP3A4, and CYP3A5 were genotyped using SNaPshot method with DNA samples of 127 Vietnamese-Koreans. The previous reports on the CYPs of Korean and Vietnamese populations were also analyzed for the comparative studies for the frequencies of CYP alleles. The statistical significances in allele and genotype frequencies among the ethnics were analyzed by Chi-square or Fisher's exact probability test. Although most of variants analyzed in 5 CYPs did not reach the statistically significant difference between the Vietnamese-Koreans and Vietnamese, some alleles were only found in Vietnamese-Koreans. Compared with Korean population, frequencies of CYP2D6*1 and CYP2D6*10B were statistically different from Vietnamese-Koreans (p<0.05). This is the first report to describe the CYP genotype profiles of Vietnamese-Koreans, which may provide important insight for the genotype based prediction of CYP activities of this admixture of Korean and Vietnamese.

Stability changes of immediately loaded and delayed loaded implants in edentulous mandible / 대한치과보철학회지

STATEMENT OF PROBLEM: It was reported high success rate of implant-supported fixed prostheses using with 5.6 implants on anterior mandible. Recently, immediate loading protocol was focused to overcome disadvantages of classic 2-stage delayed loading protocol. PURPOSE: This clinical study was to evaluate stability changes with time of immediately loaded and delayed loaded implants in edentulous mandible and to compare stability changes with time according to implantation sites. MATERIALS AND METHODS: Five or six implants were placed on anterior mandible depending on the arch shape. The immediately loading group was consisted of 8 patients received their prostheses within 24.48 hours after implantation. The delayed loading group was consisted of 8 patients received their definitive prostheses following classical prosthetic procedures after a healing period of 3 months. All patients were recalled every 6 months for check-up. The evaluations of radiographic examination, ISQ value measurement and recording of complication were done. To evaluate marginal bone level, intraoral periapical radiographs were taken with long cone paralleling technique. At every evaluation recall, all prostheses were removed and ISQ values were measured with Osstell(TM) on individual implants. RESULTS: 1. None of implants was failed. All implants showed stable marginal bone levels and ISQ values. 2. Marginal bone level changes with time showed statistically significant difference between immediately loading group and delayed loading group (P<0.001). 3. ISQ value changes with time did not show statistically significant difference between immediately loading group and delayed loading group (P=0.079). ISQ value decreased with time in both groups, however, all implants showed stable ISQ value at 30 months-recall evaluation. 4. Marginal bone level changes with time did not show statistically significant differences among implantation sites (P=0.604). 5. ISQ value changes with time showed statistically significant differences among implantation sites (P=0.047). ISQ values of most posterior implants decreased with time comparing to other implants. CONCLUSION: Although the marginal bone level of the terminal abutment didn't different with the other implants, ISQ value of the terminal abutment was lower than that of the other implants. Therefore, further clinical evaluation would be needed in this point of view.