Blood glucose-to-potassium ratio may help diagnose testicular torsion, retrospective study finds

Testicular torsion is one of the few diagnoses in the emergency department where hours literally decide whether an organ survives. When the spermatic cord twists, blood supply to the testicle is cut off, and ischaemia lasting more than four to eight hours typically causes irreversible damage requiring removal of the testicle. Yet the condition is notoriously difficult to separate from epididymo-orchitis, an infection or inflammation of the epididymis and testicle that produces nearly identical scrotal pain but demands the opposite treatment: antibiotics rather than immediate surgery. A new retrospective study, published in Basic and Clinical Andrology, reports that a simple ratio calculated from two routinely measured blood values, serum glucose divided by serum potassium, may help clinicians make that distinction faster and more objectively.

The research, led by Yasin Aktaş and Adem Tunçekin at a single institution in Turkey, analysed 373 patients treated between 2020 and 2024. The participants were divided into three groups based on their final diagnoses: 103 patients with surgically and sonographically confirmed testicular torsion, 120 patients with epididymo-orchitis, and 150 control patients with non-specific acute scrotal pain in whom both torsion and epididymo-orchitis had been excluded by physical examination and colour Doppler ultrasonography. Blood samples were drawn on admission, before any treatment, and the glucose/potassium ratio was computed alongside a panel of standard inflammatory indices, including the neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, and several composite systemic inflammation scores.

The rationale for looking at glucose and potassium together comes from the biology of acute stress. In severe ischaemic states, catecholamines and cortisol surge through the circulation, raising blood glucose while driving potassium down. The glucose/potassium ratio has already been studied as a prognostic marker in stroke, myocardial infarction, aortic dissection and trauma, but the authors state that its diagnostic value in suspected testicular torsion had not previously been explored. Their hypothesis was that the abrupt ischaemic pain of torsion triggers a stronger sympathoadrenal response than the more gradual inflammatory process of epididymo-orchitis, and that this metabolic signature would be visible in ordinary blood tests.

The results showed a clear stepwise pattern. The median glucose/potassium ratio was highest in the torsion group at 23.6, intermediate in the epididymo-orchitis group at 21.0, and lowest in the non-specific pain controls at 20.4, a difference that was statistically significant across all three pairwise comparisons. By contrast, the conventional inflammatory markers, including white blood cell count, neutrophil count and the composite indices, were significantly elevated in both the torsion and epididymo-orchitis groups compared with controls, but showed no significant difference between those two groups. In other words, the traditional markers could signal that something was wrong, but could not tell clinicians which of the two dangerous possibilities it was.

When the researchers tested diagnostic performance using receiver operating characteristic analysis, the glucose/potassium ratio outperformed every individual marker evaluated, achieving an area under the curve of 0.738. Using a cut-off value of 21.8, determined by the Youden index, the ratio showed a sensitivity of 66.7 percent and a specificity of 65.0 percent, with a positive predictive value of 42.1 percent and a negative predictive value of 83.7 percent. Patients with a ratio above 21.8 were 3.52 times more likely to have torsion than those below it, with an odds ratio of 3.52 and a 95 percent confidence interval of 1.97 to 6.25. Notably, the ratio showed no correlation with patient age, suggesting its diagnostic information is independent of the demographic differences between the groups.

The single-marker performance, however, was not strong enough for the authors to recommend the ratio on its own. Its sensitivity of 66.7 percent means roughly one in three torsion cases would be missed if the ratio were used alone, and the false-positive problem is real: among patients above the cut-off, 41.8 percent actually had epididymo-orchitis. To address this, the team built a combined model using binary logistic regression that integrated three independent predictors identified in multivariate analysis: younger age, higher white blood cell count, and higher glucose/potassium ratio, with respective odds ratios of 0.92, 1.30 and 1.14. The combined model achieved an area under the curve of 0.839, with a sensitivity of 75.6 percent, a specificity of 81.5 percent, a positive predictive value of 60.9 percent and a negative predictive value of 89.7 percent.

The authors frame this model not as a replacement for imaging but as a low-cost adjunctive triage tool. Colour Doppler ultrasonography remains the gold standard for diagnosing acute scrotal conditions, but it is operator-dependent and can produce equivocal results, particularly in early or partial torsion where blood flow is partially preserved. In out-of-hours settings where ultrasound access is delayed, the discussion accompanying the study argues that a model built from blood tests already collected during triage could accelerate the decision to proceed to surgical exploration without adding sequential delay, since awaiting the laboratory results does not extend the pathway if the samples are drawn at presentation.

The study carries substantial limitations that the authors acknowledge explicitly. Its retrospective, single-centre design introduces potential selection bias, and the model has not been externally validated. Serum glucose is affected by fasting status, which cannot be standardised in emergency presentations, and detailed medication histories that might transiently alter glucose or potassium levels could not be fully assessed. Because final diagnoses were confirmed using colour Doppler ultrasonography as the reference standard, the study could not perform a direct head-to-head prospective comparison between the combined model and imaging. The authors therefore describe their findings as preliminary and hypothesis-generating, calling for multicentre prospective studies with independent validation cohorts before any routine clinical implementation.

Even with those caveats, the study opens an intriguing line of investigation into how metabolic stress signatures might complement inflammatory markers in time-critical diagnostics. The epidemiological context underscores the stakes: testicular torsion predominantly affects males under 21, with an incidence of roughly 15 per 100,000, and delayed evaluation measurably increases orchiectomy rates. In the cohort studied, 61.2 percent of torsion patients underwent detorsion while 38.8 percent required orchiectomy due to testicular necrosis. If future prospective studies confirm the 21.8 cut-off value and the performance of the combined model in independent populations, a calculation that costs nothing beyond blood tests already ordered in nearly every emergency admission could become a genuinely useful piece of the diagnostic puzzle, helping clinicians prioritise urgent surgical review for the patients who need it most.

Subject of Research: Diagnostic value of the glucose/potassium ratio and a combined logistic model for distinguishing testicular torsion from epididymo-orchitis

Article Title: Glucose/potassium ratio and a novel combined model for the differential diagnosis of testicular torsion: a retrospective study

Article References: Aktaş, Y., & Tunçekin, A. (2026). Glucose/potassium ratio and a novel combined model for the differential diagnosis of testicular torsion: a retrospective study. Basic and Clinical Andrology, 36(1), Article 15. https://doi.org/10.1186/s12610-026-00313-5

Image Credits: AI Generated

DOI: 10.1186/s12610-026-00313-5

Keywords: testicular torsion, glucose/potassium ratio, epididymo-orchitis, diagnostic biomarker, retrospective study, emergency medicine, ROC analysis, colour Doppler ultrasonography, ischaemia, inflammatory markers, logistic regression, urology