Urine nerve growth factor (NGF) level, bladder nerve staining and symptom/problem scores in patients with interstitial cystitis

Interstitial cystitis (IC)/bladder pain syndrome (BPS) is a challenging disease, affecting thousands of people all around the world, especially women. Although there have been numerous theories regarding IC/BPS etiology, the physiopathology of the disease still remains unclear and there is a lack of certain treatment.

The aim of the study was to assess the role of nerve fibers and nerve growth factor (NGF) in the etiopathogenesis of IC/BPS symptoms by demonstrating if there is a correlation between urine NGF levels, amount of peripheral nerves in bladder mucosa and symptom severity.

A prospective clinical study was conducted with 15 IC/BPS patients and 18 controls. Urine NGF levels were measured by enzyme-linked immunosorbent assay (ELISA). Bladder punch biopsies were obtained from 15 IC/BPS patients and 9 controls. Immunohistochemistry was performed for S-100 to highlight peripheral nerve twigs in bladder mucosa. The O'Leary-Sant Interstitial Cystitis Symptom and Problem Index (OSICSPI) was used to assess symptom severity and effects of the disease on the patients' life.

NGF normalized to urine creatinine (NGF/Cr) levels in IC/BPS patients were significantly higher than in controls, 0.34 ±0.22 and 0.09 ±0.08 pg/mL: mg/dL, respectively (p < 0.001). The mean symptom score in IC patients was 12.27 ±2.4 (median: 12) and the mean problem score was 10.9 ±2.3 (median: 12). The mean mucosal nerve (S-100 stained) area in the IC/BPS group was significantly higher than in the controls, 2.53 ±1.90 vs 1.0 ±0.70, respectively (p = 0.018). In correlation analyses, the NGF/Cr level in IC/BPS patients was found significantly correlated with the O'Leary-Sant IC Symptom and Problem Index scores independently (p = 0.001 and p = 0.028, respectively).

NGF seems to be a promising biomarker in IC/BPS. It may help clinicians in diagnoses and patient follow-up. Thus, unnecessary, expensive and invasive tests, interventions and treatments might be avoided.

Advances in clinical and experimental medicine : official organ Wroclaw Medical University. 2018 Feb [Epub]

Senol Tonyali, Deniz Ates, Filiz Akbiyik, Duygu Kankaya, Dilek Baydar, Ali Ergen

Department of Urology, Hacettepe University School of Medicine, Ankara, Turkey., Department of Pathology, Hacettepe University School of Medicine, Ankara, Turkey., Department of Medical Biochemistry, Hacettepe University School of Medicine, Ankara, Turkey., Department of Pathology, Ankara University School of Medicine, Ankara, Turkey.