Urinalysis and urine culture are part of the standard diagnostic prior stone treatment to provide an appropriate sensitive antibiotic therapy in case of an UTI [4,5]. Yet, infectious complications can occur even with sterile urine culture prior treatment . The potential mismatch between a culture mid-stream urine and urine from the renal pelvis or a stone culture is a known issue [10,20]. In a recently published prospective, multicenter trial from Argentina and Chile with 122 PCNL patients the prior findings were confirmed. In this study was just a weak correlation (13%) between preoperative and intraoperative urine cultures seen. Postoperative infectious complications occurred in seven patients (5.7%) despite negative urine culture preoperatively, while four (57.1%) of these patients had a positive intrarenal urine or stone culture. In conclusion, the use of an intrarenal urine culture and stone culture was recommended to adapt antibiotic therapy in case of postoperative infectious complications [27▪].
Since the established preoperative diagnostic cannot provide complete certainty about the potential risk for postoperative infectious complications, more parameters are warranted.
Another study prospectively analyzed the value of CRP and white blood cell count for patients with acute renal colic pain presenting in the emergency department. 200 consecutive patients were enrolled in the study, prior antibiotic intake was an exclusion criteria. Although elevated CRP (42%) and leukocytosis (36%) were common, UTI proven by urine culture was seldom (13%). White blood cell count did not correlate with UTI in Receiver Operating Characteristic Curve (ROC Curve) curve analysis. In a multivariate model, suspicious urinalysis, five-fold increased CRP value and age at least 54 years were predictive for UTI. Especially in the subgroup of patients at least 54 years of age and not clearly suspicious urinalysis, a five-fold increased CRP was a significant predictor for UTI [odds-ratio (OR) 6.508; 95%-confidence interval (CI): 1.826–23.192]. Suspicious urinalysis was defined as either positive nitrite in dipstick or bacteria more than 20/hpf (high power field) or leukocytes more than 20/hpf in urine sediment. The authors concluded that a routine antibiotic usage is just necessary in colic patients with obvious suspicious urinalysis and CRP might be helpful in older patients with inconclusive urinalysis [28▪].
AUA best practice guidelines recommend intravenous antibiotics for 24 h or less in patients undergoing URS. Chew et al. analyzed the impact of prolonged antibiotic therapy postoperatively in a double center cohort, retrospectively. Out of 42 patients who received preoperative single-dose antibiotics, two developed an UTI within a 4-month period postoperatively (4.8%). This was compared with 39 patients who received an additional postoperative antibiotic therapy at surgeon's discretion and encountered four UTIs (10.2%). Epidemiological and perioperative parameter were balanced in both groups. In conclusion, single-dose antibiotics prior URS are supposed to be sufficient and a prolonged antibiotic intake postoperatively not beneficial for UTI prevention .
These results are supported by a recent retrospective trial with 1068 patients undergoing a URS in four academics hospitals. Patients with positive or missing preoperative urine culture were excluded. 337 patients with a single-dose antibiotic (group 1) were compared with 731 patients with supplemental antibiotics (group 2). Although the BMI was slightly higher in group 2 (29.6 vs. 30.5; P = 0.039), the rate of postoperative ureteral stent placement was higher in group 1 (40.1 vs. 32.4%; P = 0.0149), otherwise the groups were balanced. Within a 30-days follow-up a difference was neither seen in the postoperative UTI rate (3.6 vs. 2.9%, P = 0.546), nor in the unplanned hospital encounters (27.0 vs. 23.7%, P = 0.240). In multivariate analysis only culture-proven UTI within 1 year prior URS correlated significantly with a postoperative UTI, irrespective of antibiotic group (OR 10.8, P < 0.0001) [31▪].
An intravenous single-dose antibiotic is recommended for all patients prior PCNL with an unremarkable urine culture and no other risk factors [4,5]. In the past, a pretreatment of 1 week with Ciprofloxacin 250 mg twice daily was an established procedure, since this reduced the risk of postoperative SIRS three times . A recent randomized controlled trial of Chew et al. analyzed perioperative antibiotics prior to PCNL in a low infection risk population. 43 patients were randomized to nitrofurantoin 100 mg twice daily for 7 days preoperatively while a control arm of 43 patients received no oral antibiotics. All participants received perioperative doses of ampicillin and gentamicin. Prone PCNL was performed by urologists blinded to randomization. The primary outcome was the development of sepsis. The sepsis rate was not statistically different between the treatment and control groups (12 and 14%, respectively, 95% CI −0.163–0.122, P = 1.0). The authors concluded that there is no advantage providing 1 week of preoperative oral antibiotics in patients at low risk for infectious complications who undergo PCNL [32▪▪]. On the whole, this methodically profound study showed that reducing antibiotic usage is possible and save which is an important approach to ABS.
Beside preoperative factors which might increase the risk of postoperative infectious complications, several intraperative and postoperative risk factors are known (Table 1). In a prospective single center cohort study the impact of residual stone fragments after 30F PCNL on the occurrence of postoperative SIRS was assessed. Antibiotic prophylaxis was started directly with surgery and given until the 14F nephrostomy tube was removed after 2–3 days. Patients with UTI in preoperative urine culture received sensitive antibiotics for at least 7 days prior surgery. 94 (13%) of 729 patients developed SIRS postoperatively. Positive intrarenal urine or stone culture were more common in the SIRS group (26.6 vs. 12.3%, P = 0.003), so were residual fragments (37.2 vs. 26.5%, P = 0.03) assessed by radiograph or computed tomography scan [11▪].
More high-quality studies are warranted to select patients on risk for infectious complications and to optimize their perioperative antibiotic therapy. Furthermore, such data is needed to safely cut down antibiotic usage for patients undergoing urolithiasis therapy.
Improved diagnostics like DNA sequencing and the growing knowledge about the human microbiome might improve our antibiotic strategy in the future .
Papers of particular interest, published within the annual period of review, have been highlighted as:
1. Sasse A, Mertens R, Sion JP, et al. Surgical prophylaxis in Belgian hospitals: estimate of costs and potential savings. J Antimicrob Chemother 1998; 41:267–272.
2. Çek M, Tandoğdu Z, Naber K, et al. Antibiotic prophylaxis
in urology departments, 2005–2010. Eur Urol 2013; 63:386–394.
4. Assimos D, Krambeck A, Miller NL, et al. Surgical management of stones: American Urological Association/Endourological Society Guideline, PART I. J Urol 2016; 196:1153–1160.
6. Somani BK, Giusti G, Sun Y, et al. Complications associated with ureterorenoscopy
(URS) related to treatment of urolithiasis
: the Clinical Research Office of Endourological Society URS Global study. World J Urol 2017; 35:675–681.
7. de La Rosette J, Assimos D, Desai M, et al. The Clinical Research Office of the Endourological Society Percutaneous Nephrolithotomy
Global Study: indications, complications, and outcomes in 5803 patients. J Endourol 2011; 25:11–17.
8. Michel MS, Trojan L, Rassweiler JJ. Complications in percutaneous nephrolithotomy
. Eur Urol 2007; 51:899–906. discussion 906.
9. Seitz C, Desai M, Häcker A, et al. Incidence, prevention, and management of complications following percutaneous nephrolitholapaxy. Eur Urol 2012; 61:146–158.
10. Mariappan P, Smith G, Bariol SV, et al. Stone and pelvic urine culture and sensitivity are better than bladder urine as predictors of urosepsis following percutaneous nephrolithotomy
: a prospective clinical study. J Urol 2005; 173:1610–1614.
11▪. Degirmenci T, Bozkurt IH, Celik S, et al. Does leaving residual fragments after percutaneous nephrolithotomy
in patients with positive stone culture and/or renal pelvic urine culture increase the risk of infectious complications? Urolithiasis
2018; [Epub ahead of print].
The prospective trial underlines the importance of the stone-free status after percutaneous nephrolithotomy (PCNL) to prevent infectious complications postoperatively.
12. Chen L, Xu Q-Q, Li J-X, et al. Systemic inflammatory response syndrome after percutaneous nephrolithotomy
: an assessment of risk factors. Int J Urol 2008; 15:1025–1028.
13. Gonen M, Turan H, Ozturk B, Ozkardes H. Factors affecting fever following percutaneous nephrolithotomy
: a prospective clinical study. J Endourol 2008; 22:2135–2138.
14. Gutierrez J, Smith A, Geavlete P, et al. Urinary tract infections and postoperative fever in percutaneous nephrolithotomy
. World J Urol 2013; 31:1135–1140.
15. Ganesan V, Brown RD, Jiménez JA, et al. C-reactive protein and erythrocyte sedimentation rate predict systemic inflammatory response syndrome after percutaneous nephrolithotomy
. J Endourol 2017; 31:638–644.
16. Sharifi Aghdas F, Akhavizadegan H, Aryanpoor A, et al. Fever after percutaneous nephrolithotomy
: contributing factors. Surg Infect 2006; 7:367–371.
17. Fernandez A, Foell K, Nott L, et al. Percutaneous nephrolithotripsy in patients with urinary diversions: a case–control comparison of perioperative outcomes. J Endourol 2011; 25:1615–1618.
18. Draga ROP, Kok ET, Sorel MR, et al. Percutaneous nephrolithotomy
: factors associated with fever after the first postoperative day and systemic inflammatory response syndrome. J Endourol 2009; 23:921–927.
19. Dogan HS, Guliyev F, Cetinkaya YS, et al. Importance of microbiological evaluation in management of infectious complications following percutaneous nephrolithotomy
. Int Urol Nephrol 2007; 39:737–742.
20. Korets R, Graversen JA, Kates M, et al. Postpercutaneous nephrolithotomy systemic inflammatory response: a prospective analysis of preoperative urine, renal pelvic urine and stone cultures. J Urol 2011; 186:1899–1903.
21. Zhong W, Zeng G, Wu K, et al. Does a smaller tract in percutaneous nephrolithotomy
contribute to high renal pelvic pressure and postoperative fever? J Endourol 2008; 22:2147–2151.
22. AlSmadi J, Fan J, Zhu W, et al. The influence of super-mini percutaneous nephrolithotomy
on renal pelvic pressure in vivo. J Endourol 2018; 32:819–823.
23. Kreydin EI, Eisner BH. Risk factors for sepsis after percutaneous renal stone surgery. Nat Rev Urol 2013; 10:598–605.
24. Seyrek M, Binbay M, Yuruk E, et al. Perioperative prophylaxis for percutaneous nephrolithotomy
: randomized study concerning the drug and dosage. J Endourol 2012; 26:1431–1436.
25. Tuzel E, Aktepe OC, Akdogan B. Prospective comparative study of two protocols of antibiotic prophylaxis
in percutaneous nephrolithotomy
. J Endourol 2013; 27:172–176.
26. Cai T, Verze P, Brugnolli A, et al. Adherence to European Association of Urology Guidelines on Prophylactic Antibiotics: an important step in antimicrobial stewardship. Eur Urol 2016; 69:276–283.
27▪. Walton-Diaz A, Vinay JI, Barahona J, et al. Concordance of renal stone culture: PMUC, RPUC, RSC and post-PCNL sepsis – a nonrandomized prospective observation cohort study. Int Urol Nephrol 2017; 49:31–35.
The prospective multicenter study from South America supports the clinical importance of intraoperative culture from urine of renal pelvis and stones, as these information can be helpful in case of postoperative infectious complications.
28▪. Rosenhammer B, Spachmann PJ, Burger M, et al. Prospective evaluation of predictive parameters for urinary tract infection in patients with acute renal colic. J Emerg Med 2018; 55:319–326.
The prospective cohort study clarifies that raised white blood cell count is common in patients with acute renal colic but nonpredictive for urinary tract infection (UTI), though a five-fold increased C-reactive protein protein can be sign for UTI.
29. Alexander CE, Gowland S, Cadwallader J, et al. Routine antibiotic prophylaxis
is not required for patients undergoing shockwave lithotripsy: outcomes from a national shockwave lithotripsy database in New Zealand. J Endourol 2016; 30:1233–1238.
30. Chew BH, Flannigan R, Kurtz M, et al. A single dose of intraoperative antibiotics is sufficient to prevent urinary tract infection during ureteroscopy. J Endourol 2016; 30:63–68.
31▪. Greene DJ, Gill BC, Hinck B, et al. American Urological Association antibiotic best practice statement and ureteroscopy: does antibiotic stewardship help? J Endourol 2018; 32:283–288.
The retrospective multicenter study supports the sufficiency of single-dose antibiotic prophylaxis during ureterorenoscopy, an prolonged antibiotic intake was not beneficial for UTI prevention.
32▪▪. Chew BH, Miller NL, Abbott JE, et al. A randomized controlled trial of preoperative prophylactic antibiotics prior to percutaneous nephrolithotomy
in a low infectious risk population: a report from the EDGE Consortium. J Urol 2018; 200:801–808.
The methodically profound randomized controlled trial supports a single-dose antibiotic prophylaxis to be sufficient for low-risk patients undergoing PCNL.
33. Gravas S, Montanari E, Geavlete P, et al. Postoperative infection rates in low risk patients undergoing percutaneous nephrolithotomy
with and without antibiotic prophylaxis
: a matched case control study. J Urol 2012; 188:843–847.
34. Mariappan P, Smith G, Moussa SA, Tolley DA. One week of ciprofloxacin before percutaneous nephrolithotomy
significantly reduces upper tract infection and urosepsis: a prospective controlled study. BJU Int 2006; 98:1075–1079.
35. Mouraviev V, McDonald M. An implementation of next generation sequencing for prevention and diagnosis of urinary tract infection in urology. Can J Urol 2018; 25:9349–9356.