The HLA Class II Associations with Rheumatic Heart Disease in South Indian Patients: A Preliminary Study

A case of rheumatic valvular heart disease and autoimmune gastritis

We present a case of a 50-year-old female patient with a history of depressive disorder and anaemia (attributed to menorrhagias). She was admitted to the cardiology department with symptoms of fatigue on moderate exertion for several months, with worsening in the month before hospitalisation. Echocardiography revealed a severe mitral stenosis of rheumatic aetiology. Laboratory tests showed microcytic and hypochromic anaemia, reduced iron stores and vitamin B12 levels, and positive serum antiparietal cells autoantibodies. Endoscopy showed focal areas of erythema in the stomach, corresponding histologically to chronic atrophic gastritis. In this context, two distinct clinical entities were diagnosed in the same patient: severe rheumatic mitral stenosis and autoimmune gastritis. The patient was started on vitamin B12 and iron supplementation and underwent surgical correction of the valvular disease. There was symptomatic improvement in her signs of fatigue.

Rheumatic heart disease in Uganda: the association between MHC class II HLA DR alleles and disease: a case control study

BACKGROUND

Rheumatic heart disease (RHD), the only long term consequence of acute rheumatic fever, remains a leading cause of morbidity and mortality among young adults in Uganda. An inherited susceptibility to acute rheumatic fever centers around the major histocompatibility class II human leucocyte antigens. However, there is paucity of data from sub-Saharan Africa. This study compares the frequency of HLA class II DR alleles between RHD cases and normal controls in Uganda.

METHODS

One hundred ninety-nine participants including 96 established RHD cases aged 5-60 years and 103 age and sex matched normal controls were recruited for participation. DNA was manually extracted from buffy coat samples and HLA analysis was performed. HLA-DR allelic frequency comparison between cases and controls were estimated using conditional logistic regression with 95% confidence intervals. P -values were corrected for multiple hypothesis testing.

RESULTS

199 participants (103 female, 51.8%) completed the study. The mean (SD) age in years for cases and controls were 29.6 (10.2) and 29(18), respectively. After conditional logistic regression and multiple hypothesis testing, HLA-DR1was associated with a decreased risk of RHD (OR = 0.42, CI 0.21-085, P = 0.01, Corrected P value (PC) = 0.09,) while HLA-DR11 was associated with increased risk of RHD (OR = 3.31, CI 1.57-6.97, P = <0.001, Pc < 0.001). No other significant associations were found.

CONCLUSION

In this first study of HLA genetic susceptibility to RHD in Uganda, HLA- DR1 was more common in normal controls while HLA- DR11 was more common among RHD cases suggesting a disease susceptibility association. In future studies, high resolution HLA analysis and genome wide studies should be carried out to confirm this pattern.