A study of correlation between nut-cracker phenomenon and varicocele in adults

Abstract

Objective To explore the correlation and significance between adult nut-cracker phenomenon (NCP) and varicocele. Methods The clinical characters of 226 adult patient (including inpatients and outpatients)with NCP diagnosed by color Doppler ultrasound examination were analyzed retrospectively, whose chief complaints were asymptomatic bematuria or/and orthostatic proteinuria (microalbuminuria). The ratio of left renal vein inner diameter before and after being compressed≥2 was regarded as the criteria of diagnosis of NCP. Among 226 cases, 184 male NCP patients were taken as study group, and the incidence of varicocele was tested. One hundred and fifty-six male adults who had physical examination in the same period and whose ages matched with study group were taken as control group, they were not NCP patients examined by color Doppler ultrasound. The incidence of varicocele was compared between two groups. The indexes associated NCP were examined in detail in study group. Logistic regression analysis was used to study the correlation between NCP and left varicocele. Results There were 184 male patients in study group, among which there were 22 patients with left sub-clinical varicocele (accounted for 11.96%), 47 patients with left varicocele (accounted for 25.54%).The total incidence of varicocole was 37.50%(69/184). There were 156 male adults in control group, among which there were 13 patients with sub-clinical varicocole(accounted for 8.33%), 8 patients with varicocele (accounted for 5.13%).The total incidence of varicocele was 13.46%(21/156). The total incidence of varicocele in study group was significantly higher than that in control group (P=0.000). In study group, there were 22 patients with left sub-clinical varicocele,with average age (24.73±1.03) years. The inner diameter of left renal vein(LRV) in front of spine was (3.65±0.11) mm(a),the inner diameter of LRV at left side of spine was (8.41±0.11)mm(b), and b/a ratio was 2.31± 0.06. The angle between superior mesenterie artery (SMA) and abdominal aorta(AA) was (15.95±0.59)°. There were 47 patients with left varicocele, with average age(26.62±1.74)years. The inner diameter of LRV in front of spine was (3.43±0.08)mm(a),the inner diameter of LRV at left side of spine was (8.72±0.14) mm (b), and b/a ratio was 2.54±0.08. The angle between SMA and AA was (14.54±0.53)°. In study group, Lagistic regression analysis proved that male patients with NCP were complicated with varicocele easier when the angle between SMA and AA became smaller, the inner diameter of LRV at the left side of spine (b)and age increased. Conclusions Male adult patients with NCP are complicated with left varicocele, which is significantly higher than that in non-NCP male adults at the same age. It shows that NCP is one important cause for varicocele and there is a close correlation between NCP and varicocele in male adults. Key words: Adult; Varicocele; Albuminuria; Nut-cracker phenomenon