Urolithiasis and cholelithiasis are public health problems, the prevalence of which has been increasing worldwide [1–3]. Urolithiasis refers to the formation of stone(s) in the urinary tracts . This includes nephrolithiasis (renal calculi, or kidney stones), ureterolithiasis (ureter calculi), and cystolithiasis (bladder calculi) [5–6]. Urolithiasis is mostly lodged in the kidney(s) , and is the third common disease of the urinary tract . Nephrolithiasis is a systemic disorder and has been associated with chronic kidney disease (CKD)-end-stage renal failure [9–11], cardiovascular diseases , diabetes mellitus, hypertension and obesity [2, 13–14]. Even mild CKD is associated with significant adverse cardiovascular events . Clinical manifestations of nephrolithiasis include renal colic, blockage of urine flow, kidney swelling, bloody urine and secondary bacterial infection . This imposes a significant impact on quality of life and the nation’s economy .
The cause for kidney stones is multi-factorial including epidemiological, biochemical, and genetic factors [18–20]. The pathogenesis of kidney stone formation is a complex biochemical process and remains incompletely understood . A kidney stone is formed as the result of an imbalance between promoters and inhibitors in the urine, kidneys . The types of kidney stones are calcium stones, struvite or magnesium ammonium phosphate stones, uric acid stones or urate, cystine or ammonium acid citrate stones and drug-induced stones . Calcium stones comprise about 80% of the urinary tract stones . After the first episode of a stone, the 10-year recurrence rate is more than 50% [25–26].
Globally, the prevalence of kidney stones is between 2% and 20% [27–28] including infants . It affects approximately 1 in 11 people in the United States . This prevalence may be influenced by variations in sex, age, race, and changes in dietary practices and global warming . Sun exposure enhances vitamin D production which leads to an increase in 25-hydroxy vitamin D . The classic effect of vitamin D is to facilitate the intestinal absorption of calcium by mediating active calcium transport across the intestinal mucosa .
In Germany, there has been an increase in the prevalence of urolithiasis within the last 22 years. It was reported that most kidney stones are frequently formed in men than in women between 20 and 49 years old . In addition, Ahuja et al. (33) reported higher stone occurrences in men than in women between the ages of 30 and 39. In contrast, the majority of kidney stones have been reported to occur in females than males of the age group 20 to 40 .
Gallstone disease is a widespread disorder all over the world . Cholesterol-supersaturated bile is the first requirement for gallstone formation, and Gallbladder stores bile secreted from the liver and passes it in response to a fat-rich diet. When the bile contains a high level of cholesterol, it becomes hardened or crystalline to form cholelithiasis or gallstones (Chung-Jyi et al., 2004). The most predominant type of gallstone is cholesterol stone which constitutes more than 80% of gallstones in the Western world (Acalovschi, 2001). The rare types of gallstones are pigment stones (composed of bile pigments) and the mixed stones (bile salts)(Channa et al., 2007b). In general, cholelithiasis is a leading cause of emergency hospital admission among gastrointestinal problems (Portincasa et al., 2006). Cholecystectomy is one of the most common elective abdominal operations in Europe and the United States. Most gallstones never generate symptoms, but they can cause biliary pain and biliary complications such as acute cholecystitis, jaundice, ascending cholangits, and acute pancreatitis. Such complications of gallstones contribute substantially to health care costs .
Beside a genetic predisposition the likelihood of gallstone formation is influenced by some known risk factors. The main risk factors for gallstone formation includes obesity, estrogen treatment and pregnancy [35, 13, 36] metabolic syndrome [13, 37], Diabetes mellitus , being female gender and increasing age [35,39]. Moreover, lifestyle modifications such as dietary habits, and lack of physical exercise are also associated with gallstones [40–41]. The risk of developing renal stone is higher among patients with gallstones than without it. Also, the prevalence of gallstones was significantly higher among patients with chronic kidney disease. However, whether renal stones and gallstones share a pathophysiological mechanism remains unclear .
Globally, the national prevalence of gallstones vary, and over 10% of people have gallstones in Western countries . There has been an increase in the Hospital admission rates for cholelithiasis in males (30%) and in females (64%) , and substantially increased the economic burden on nations’ health care systems [45–46]. Gallstones can be asymptomatic or accompanied by various clinical symptoms such as biliary colic, cholecystitis, obstructive jaundice and pancreatitis .
The recurrent stone disease causes not only pain and distress in patients, but it also imposes a significant economic burden due to loss of working days and associated health care costs. Currently, less invasive surgical therapies such as extracorporeal shockwave lithotripsy (ESWL), percutaneous nephrolithotomy (PCNL), or ureteroscopy (URS) have revolutionized acute and complex stone management. However, these often result in incomplete stone clearance . Although the analysis of stone chemical composition may influence the choice of intervention , open surgery is still the mainstay of treatment . In Ethiopia, reports on the prevalence of urolithiasis and gallstones are scarce. Therefore, the present study intends to determine the prevalence of urolithiasis and gallstone diseases among patients that attended St. Paulos Referral Hospital during the past 13 years (2005/6 to 2017/18).