<em>L. donovani</em> infections (visceral and post kala-azar dermal leishmaniases) are characterized by infection-induced reversible immune suppression. Autoimmunity is a well-documented phenomenon among p...<em>L. donovani</em> infections (visceral and post kala-azar dermal leishmaniases) are characterized by infection-induced reversible immune suppression. Autoimmunity is a well-documented phenomenon among patients with primary immune deficiencies. This study aimed to study auto-immune phenomena accompanying <em>L. donovani</em> infections. In a prospective case-controlled study and following informed consent, 155 individuals with visceral leishmaniasis (VL;<em>n</em> = 62), post kala-azar dermal leishmaniasis (PKDL;<em>n</em> = 31) and apparently healthy volunteers (<em>n</em> = 62) were recruited. Sera antinuclear (ANA), anti-dsDNA, anti-thyroid peroxidase (TPO), anti-smooth muscles (ASMA) and F-actin auto-antibodies were measured using ELISA and indirect immune-fluorescence assay. The mean ages of VL, PDKL patients and apparently healthy volunteers were: 17.5 ± 12.5, 15.0 ± 7.0 and 17.5 ± 9.5 years with Male:Female ratios of 2:0, 1:2 and 1:5 respectively. Significantly high frequencies of F-actin (74.2%;46/62) and ASMA (50%;31/62) auto-antibodies were seen among VL patients (<strong><em>p</em> = 0.003</strong>, <strong><em>p</em> = 0.001</strong>) compared to apparently healthy volunteers. Likewise, significantly high frequencies of F-actin (64.5%;20/31;<strong><em>p</em> = 0.001</strong>), ASMA (42%;13/31;<strong><em>p</em> = 0.003</strong>), ANA (36%;11/31;<strong><em>p</em> = 0.00</strong><strong>1</strong>) and anti-dsDNA (16%;5/31;<strong><em>p</em> = 0.01</strong>) auto-antibodies were seen among PKDL patients. Development of tissue-based autoantibodies in <em>L. donovani</em> infections probably indicates loss of peripheral tolerance with activation of circulating auto-reactive T and B cells probably contributing to disease pathogenesis (increased bilirubin/liver enzymes, prolonged QT interval/arrythmias and blood cytopenias). In conclusion, <em>L. donovani</em> infection-induced immune suppression with development of tissue-based auto-antibodies is prevalent among Sudanese patients with VL and PKDL leishmaniases and contributes to some aspects of the disease pathogenesis.展开更多
文摘<em>L. donovani</em> infections (visceral and post kala-azar dermal leishmaniases) are characterized by infection-induced reversible immune suppression. Autoimmunity is a well-documented phenomenon among patients with primary immune deficiencies. This study aimed to study auto-immune phenomena accompanying <em>L. donovani</em> infections. In a prospective case-controlled study and following informed consent, 155 individuals with visceral leishmaniasis (VL;<em>n</em> = 62), post kala-azar dermal leishmaniasis (PKDL;<em>n</em> = 31) and apparently healthy volunteers (<em>n</em> = 62) were recruited. Sera antinuclear (ANA), anti-dsDNA, anti-thyroid peroxidase (TPO), anti-smooth muscles (ASMA) and F-actin auto-antibodies were measured using ELISA and indirect immune-fluorescence assay. The mean ages of VL, PDKL patients and apparently healthy volunteers were: 17.5 ± 12.5, 15.0 ± 7.0 and 17.5 ± 9.5 years with Male:Female ratios of 2:0, 1:2 and 1:5 respectively. Significantly high frequencies of F-actin (74.2%;46/62) and ASMA (50%;31/62) auto-antibodies were seen among VL patients (<strong><em>p</em> = 0.003</strong>, <strong><em>p</em> = 0.001</strong>) compared to apparently healthy volunteers. Likewise, significantly high frequencies of F-actin (64.5%;20/31;<strong><em>p</em> = 0.001</strong>), ASMA (42%;13/31;<strong><em>p</em> = 0.003</strong>), ANA (36%;11/31;<strong><em>p</em> = 0.00</strong><strong>1</strong>) and anti-dsDNA (16%;5/31;<strong><em>p</em> = 0.01</strong>) auto-antibodies were seen among PKDL patients. Development of tissue-based autoantibodies in <em>L. donovani</em> infections probably indicates loss of peripheral tolerance with activation of circulating auto-reactive T and B cells probably contributing to disease pathogenesis (increased bilirubin/liver enzymes, prolonged QT interval/arrythmias and blood cytopenias). In conclusion, <em>L. donovani</em> infection-induced immune suppression with development of tissue-based auto-antibodies is prevalent among Sudanese patients with VL and PKDL leishmaniases and contributes to some aspects of the disease pathogenesis.
