Epidemiological, Clinical and Progressive Aspects of Hemolytic-Uremic Syndrome in N’Djamena, Chad

Introduction: Hemolytic-uremic syndrome (HUS) is an endothelial disease often associated with renal damage with an evolution that can be deleterious. Chronic kidney disease is rare and represents 3% of cases. Few studies have been initiated in sub-Saharan Africa. In Dakar, in 2016, in a series that included 4 cases of typical post-infectious hemolytic-uremic syndrome over a period of 5 and a half years, there were 3 deaths and 1 case progressed to chronic renal failure in 6 months. Atypical hemolytic-uremic syndrome is a rare disease that is secondary to failure to control the activation of the serum complement alternative pathway. Atypical hemolytic-uremic syndrome is a rare disease that is associated primarily with mutations or autoantibodies leading to dysregulated complement activation. No studies had been carried out in Chad. The aim of this study is to describe the clinical, paraclinical and progressive characteristics of hemolytic-uremic syndrome in N’Djamena, Chad.

Methodology: This is a descriptive cross-sectional study carried out over a period of 4 years from January 1, 2018 to December 31, 2022 in the nephrology department of the Renaissance University Hospital Center in N’Djamena, Chad. Patients aged 18 years and above, hospitalized for hemolytic-uremic syndrome were included.

Results: There were 13 patients that were included in the study. The median age was 45 ±18.8 years [6 to 60 years]. There were 11 male patients (84.6%), giving a sex ratio of 5.5. We noted in the series, the presence of 6 children with an average age of 6.4 years (4 to 15 years). The main reason for consultation was vomiting in 6 patients (46.2%) and abdominal pain in 3 patients. On examination, 5 patients (38.5%) had anuria and 2 patients (15.4%) had fever. All patients had elevated levels of C-reactive protein (>6 mg/l) with a median level of 83.1 mg/l [27-145 mg/l]. All patients presented with mechanical hemolytic anemia. The median serum creatinine was 977.3 μmol/l [423.6-1664.7 μmol/l]. There were 7 patients (53.8%) who had severe acute renal failure (KDIGO stage 3). The etiology found 6 cases of severe post-malaria hemolytic-uremic syndrome (HUS), 3 cases of typical HUS, 2 cases of atypical HUS, 1 case of HUS secondary to HIV infection and 1 case of post-pneumococcal HUS.

Conclusion: Hemolytic-uremic syndrome is a rare but often poorly described pathology in sub-Saharan Africa. Its prevalence in Chad is 0.88%. The causes of HUS remain dominated by severe malaria in adults and digestive E. coli infections in children. The high mortality is partly explained by the severity of the symptoms but also by a lack of appropriate care.

Abbreviations: HUS: Hemolytic-uremic syndrome; CKD: chronic kidney disease; AKI: acute kidney injury.

Keywords: Hemolytic-uremic Syndrome, Acute renal failure, Chad.