Tesis

Hubungan Antara Kadar Serum Vitamin D (25Hydroxyvitamin D) dan Kadar Plasma Reseptor Vitamin D dengan Indeks Bakteri Pada Pasien Kusta = Association between Serum Level of Vitamin D (25Hydroxyvitamin D) and Plasma Level of Vitamin D Receptor with Bacteriological Index in Leprosy Patients.

Latar belakang: Perjalanan penyakit kusta tidak hanya dipengaruhi oleh faktor bakteri, tetapi juga oleh faktor pejamu yaitu genetik dan imunitas. Salah satu peran sistem imunitas terhadap infeksi M.leprae adalah respons makrofag melalui interaksinya dengan vitamin D dan reseptor vitamin D (RVD). Vitamin D diketahui memiliki peran ekstraskeletal yaitu sebagai imunomoduulator dan antimikroba. Interaksi vitamin D dengan RVD pada berbagai sel imun akan menstimulasi ekspresi peptida antimikroba yaitu katelisidin yang dapat menghancurkan integritas membran sel bakteri. Beberapa penelitian terbaru melaporkan baik kadar vitamin D maupun RVD pada pasien kusta dengan berbagai hasil. Hingga saat ini belum ada penelitian yang menghubungkan kadar vitamin D dan RVD dengan nilai indeks bakteri (IB) pada pasien kusta di Indonesia. Tujuan: Menganalisis kadar serum 25-hydroxyvitamin D(25(OH)D) dan kadar plasma RVD serta hubungannya dengan IB pada pasien kusta di Indonesia. Metode: Penelitian observasional-analitik ini dilakukan dengan desain potong lintang. Sebanyak 28 pasien yang terdiagnosis kusta baru direkrut dalam penelitian ini. Pemeriksaan IB dilakukan dengan slit-skin smear. Diagnosis kusta ditegakkan berdasarkan tanda kardinal kusta. Penelitian ini juga menilai kecukupan pajanan matahari menggunakan kuesioner pajanan matahari mingguan. Kadar serum 25(OH)D diperiksa dengan in vitro chemiluminescent immunoassay (CLIA). Pemeriksaan kadar plasma RVD dilakukan dengan metode enzyme linked immunosorbent assay (ELISA). Analisis statistik yang sesuai dilakukan untuk membuktikan hipotesis penelitian. Nilai p < 0,05 dianggap signifikan secara statistik. Hasil: Median kadar serum 25(OH)D adalah 12,68 ng/ml (4,88 – 44,74). Mayoritas subjek mengalami defisiensi vitamin D (71,4%). Tidak terdapat korelasi antara kadar serum 25(OH)D dengan nilai IB (r = 0,033; p = 0,869). Median kadar plasma RVD adalah 1,36 ng/ml (0,26 – 8,04). Tidak terdapat korelasi antara kadar plasma RVD dengan IB (r = -0,063; p = 0,749). Berdasarkan analisis regresi multivariat, tidak terdapat hubungan antara IB dengan kadar serum 25(OH) dan kadar plasma RVD (R square = 0,055). Selain itu, didapatkan korelasi positif kuat antara kadar serum 25(OH)D dengan skor pajanan sinar matahari (r = 0,863; p < 0,001). Kesimpulan: Tidak terdapat hubungan antara kadar serum 25(OH)D dan kadar plasma RVD dengan IB pada pasien kusta
Kata kunci: vitamin D, reseptor vitamin D, indeks bakteri, pajanan matahari


Background: The clinical course of leprosy is not only influenced by bacterial factor, but also host factors, such as genetics and immunity. One of many immunity system’s roles against M. leprae infection is macrophage response through its interaction with vitamin D and vitamin D receptor (VDR). Vitamin D is known to have extra-skeletal properties, namely immunomodulator and antimicrobial properties. The interaction between vitamin D and VDR in various immune cells will stimulate the expression of antimicrobial peptides, such as cathelicidin which can destroy the integrity of bacterial cell membrane. Several new studies reported vitamin D and VDR levels in leprosy patients with various results. To date, there has been no study which analyzes the association between vitamin D and VDR with bacteriological index (BI) in leprosy patients in Indonesia. Objective: To analyze the serum level of 25-hydroxyvitamin D₃ (25(OH)D) and plasma level of VDR as well as their association with IB in leprosy patients in Indonesia. Methods: This observational analytic study was performed with cross-sectional design. A total of 28 newly-diagnosed leprosy patients were recruited into the study. BI examination was performed with slit-skin smear. The diagnosis of leprosy was established based on the cardinal signs. This study also assessed the patient’s sun exposure with weekly sun exposure questionnaire. Serum level of 25(OH)D was assessed with in vitro chemiluminescent immunoassay (CLIA). Plasma level of VDR was assessed with enzyme linked immunosorbent assay (ELISA) method. Appropriate statistical analysis was performed to prove the study hypothesis. P-value < 0,05 was considered statistically significant. Results: Median serum level of 25(OH)D was 12.68 ng/ml (4.88 – 44.74). Majority of the subjects had vitamin D deficiency (71.4%). There was no correlation between serum level of 25(OH)D and IB (r = 0.033; p = 0.869). Median plasma level of VDRwas 1.36 ng/ml (0.26 – 8.04). There was no correlation between plasma level of VDR and BI (r = -0.063; p = 0.749). Based on multivariate regression analysis, there was no significant association between BI and serum level of 25(OH) and plasma level of VDR (R square = 0.055). In addition, there was strong positive correlation between serum level of 25(OH)D and sun exposure score (r = 0.863; p < 0.001). Conclusions: There was no association between serum level of 25(OH)D and plasma level of RVD with IB in leprosy patients
Keyword: vitamin D, vitamin D receptor, bacteriological index, sun exposure