Purpose: Analysis of urinary stones is important to provide adequate treatment, prevention, and health educations. The purpose of this study was to determine the type, composition, age, gender and anatomic sites of urinary stones, and their relationships with metabolic syndromes in patients treated at NCKH during the period from 2010 to 2015.
Materials and Methods: We retrospectively reviewed patients who received stone analysis from 2010 to 2015 in a single medical center in South Taiwan. A total 1061 patients was enrolled. Stone specimen was submitted by patients or collected by endoscopic surgery to NCKUH. All stone analyses were performed at the clinical laboratory. Other than stone analyses, serum creatinine, urine pH value, 24hr urine calcium, and 24hr urine citrate were all collected. Based on preoperative image, stone location and stone size were also recorded.
Results: Among all, CaOx remained the most common stone component (53.3%), which followed by Ca3(PO4)2 (27.9%). Mean age of all patients was 58.79 year old. Brushite stone accounted for 1.8%. Patients with metabolic stones were significantly older than CaOx or Ca3(PO4)2 (69 v.s. 55 and 58) (p < 0.01 ). The ratio of male and female was obviously high in CaOx (8.3:1) and metabolic group (28.0:1). Infection stone was dominant in female population (1:2.8). Urine pH was lower in CaOx and metabolic groups (pH = 5.9 and 5.8). 24hr urine calcium was significantly higher in CaOx group (219 mg/day, p < 0.01 ). Pre-operative renal function was worst in metabolic group (eGFR = 51.4 mL/min/1.73m2 ). Infection stones were prone to recur than other stone components, which need 2.2 times of procedure to manage. On the other hand, the stone component distribution changed within age. Older people will have more Ca3(PO4)2 and infection stones.
Conclusion: CaOx was still the most common stone components in South Taiwan. However, Ca3(PO4)2 accounted for more percentage in South Taiwan than other reports before. Interesting, metabolic stones shared higher incidence in South Taiwan, which may be explained to be related to unique climate and diet habits. Metabolic stones had also higher incidence in older groups.