Chronic Kidney Disease of Unknown Origin: A Mysterious Epidemic

Abstract

Amongst the many threats to health in our world, the most challenging ones are the ones with unknown causes. There is a mysterious epidemic of kidney disease called chronic kidney disease of unknown etiology (CKDu) that is occurring in many parts of the world. Unrelated to known risk factors such as diabetes and hypertension, CKDu mostly affects the young and middle-aged, with slight preponderance in males. It mostly occurs in people living in rural areas, especially working in agricultural jobs. Worldwide, the number of people with chronic kidney disease, and those who need dialysis and renal replacement, is increasing every year as compared to other chronic conditions like diabetes and AIDS. It's not just alarming but a great challenge to healthcare systems across the world, especially in resource-poor countries. CKDu has become a silent killer for most patients. The occurrence of end-stage renal disease (ESRD) in CKDu can be catastrophic for individuals, especially in countries with limited medical facilities, causing a significant socio-economic burden. Even within these economically developing nations, people affected by CKDu usually are from the most vulnerable and underserved populations. As a definitive etiology has not been postulated for CKDu to date, this comprehensive review was undertaken to throw light on the poorly understood epidemiologic risk factors and the course of the disease.

Chronic kidney disease with unknown cause across the global spectrum

“…Smoking was associated with CKDu in Sri Lanka, although not in Guatemala [19,20]. Nonsteroidal anti-inflammatory agents (NSAIDs) were commonly taken by up to 77.9% of CKDu patients in some areas of Central America but not others, and infrequently used in Sri Lanka [7 ▪ ,16]. Indigenous and over-the-counter pain medication use was reported frequently in CKDu patients in India while ayurvedic medication is a possible risk factor in Sri Lanka [4].…”

“…Around the world, CKDu has common clinical features including an asymptomatic period with late presentation, nonnephrotic range proteinuria and blood pressure of less than 140/90 in early disease. Some features appear to be geographically restricted [16] (Table 2). Diabetes, significant hypertension, and high-grade proteinuria are considered exclusionary, although may occur in later stages of CKDu [17].…”

Chronic kidney disease of unknown aetiology in Africa: A review of the literature

“…Over the past two decades, an epidemic of CKD unrelated to these traditional risk factors has been recognized in many LMICs. 6,7 CKD of nontraditional causes, or unknown aetiology (CKDu) mainly affects young working-age adults in poor rural communities and is often fatal due to rapid disease progression and lack of dialysis or transplant options in the affected areas. 8,9 CKDu is a growing public health concern, causing in excess of 30 000 deaths each year and is estimated to have the highest age-standardized rate of disability adjusted life years of all causes of CKD.…”

“…[10][11][12] CKDu has a devastating effect on individuals, families and the community, and imposes an enormous burden on healthcare systems. 7,13 Although the aetiology of CKDu still remains unknown, it is thought to be a disease of multifactorial origin primarily resulting from environmental factors. 9,14,15 Identification of potential risk factors is therefore crucial in mitigating exposures and ultimately reduction of disease associated morbidity and mortality.…”

“…9,14,15 Identification of potential risk factors is therefore crucial in mitigating exposures and ultimately reduction of disease associated morbidity and mortality. 7,16 In Africa, CKD is an increasingly important public health problem with risk factors that include communicable and noncommunicable diseases. 17,18 It primarily affects the economically productive young adults and appears to be a more severe form than in developed countries.…”