A systematic review and meta‐analysis of clinical signs, symptoms, and imaging findings in patients with suspected renal colic

Abstract

Study Objective The objective of this study was to conduct a systematic review and meta‐analysis of the diagnostic accuracy of the clinical signs, symptoms, laboratory investigations, and imaging modalities commonly used in patients with clinically suspected renal colic. Methods We conducted this systematic review and meta‐analysis according to an a priori, registered protocol (PROSPERO CRD42017055153). A literature search was performed using MEDLINE and EMBASE from inception to July 2, 2020. We assessed the risk of bias using Quality Assessment of Diagnostic Accuracy Studies–2, calculated likelihood ratios (LRs), and applied a random‐effects model for meta‐analysis. Results Among 7641 references screened, 76 were included in the systematic review and 53 were included in the meta‐analyis. The overall pooled prevalence for ureteral stones was 63% (95% confidence interval [CI], 58%–67%). No individual demographic feature, symptom, or sign when present had an LR+ ≥2.0 for identifying ureterolithiasis. A (Sex, Timing and Origin of pain, race, presence or absence of Nausea, and Erythrocytes) STONE score ≥10 increased (sensitivity 0.49, specificity 0.91, LR 5.3 [95% CI, 4.1–6.7]) and a STONE score <6 reduced the likelihood of ureteral stones (sensitivity 0.94, specificity 0.43, LR 0.15 [95% CI, 0.10–0.22]). Standard‐dose (sensitivity 0.96, specificity 0.94, LR+ 16 [95% CI, 11–23], LR− 0.05 [95% CI, 0.03–0.07]) and low‐dose computed tomography (CT) scanning (sensitivity 0.93, specificity 0.94, LR+ 17 [95% CI, 8.8–31], LR− 0.08 [95% CI, 0.03–0.19]) were the most useful imaging techniques for identifying patients with or without ureteral stones. Conclusions Individual signs, symptoms, or the presence of microscopic hematuria do not substantially impact the likelihood of ureteral stones in patients with clinically suspected renal colic. The STONE score at high and low thresholds and a modified STONE score at a high threshold may sufficiently guide physicians’ decisions to obtain imaging. Low‐dose, non‐contrast CT imaging provides superior diagnostic accuracy compared with all other imaging index tests that are comparable with standard CT imaging. Limitations of the evidence include methodological shortcomings and considerable heterogeneity of the included studies.

Does the kidney actually swell during an acute urinary tract obstruction?

“…The typical patient with an acute obstructive ureteral stone presents with flank pain (1). Computed tomography (CT) is the imaging technique of choice in the evaluation of patients presenting with acute flank pain and suspected ureterolithiasis due to its high sensitivity and specificity for calcifications (2–6). Hydronephrosis (dilatation of the renal pelvis and calyces), hydroureter (dilatation of the ureter proximal to the obstruction), perirenal stranding (edema in the perirenal fatty tissue), thickening of the renal fascia, and unilateral renal swelling are radiological features and secondary signs corresponding to the acute obstruction and increased pressure proximal to the ureteral obstruction (7).…”