Urinary nerve growth factor shows diagnostic value

By Joanna Lyford, Senior medwireNews Reporter

Urinary nerve growth factor (NGF) could be a useful biomarker for the diagnosis of overactive bladder (OAB) and a predictive biomarker to help guide treatment, Chinese researchers believe.

Their conclusion is based on a meta-analysis of nine studies, which also indicated that urinary NGF could be valuable in distinguishing between diagnoses of OAB and interstitial cystitis/painful bladder syndrome (IC/PBS).

The research, which appears in PLoS ONE, identified nine relevant studies involving 259 patients with IC/PBS, 67 patients with OAB and 208 healthy controls. All patients met clinical criteria for IC/PBS, namely, suprapubic pain with a full bladder that was relieved after voiding and associated with severe frequency and nocturia.

Compared with controls, IC/PBS patients had significantly higher urinary NGF and NGF/creatinine (Cr) levels, with standard mean differences (SMDs) of 1.94 and 1.79, respectively.

But relative to OAB patients, those with IC/PBS had significantly lower urinary NGF and NGF/Cr levels, with SMDs of –0.62 and –0.70, respectively.

Among IC/PBS patients who were followed longitudinally, meta-analysis revealed that urinary NGF levels declined significantly after successful treatment, with an average decrease of 1.74.

These findings were confirmed in a sensitivity analysis restricted to the four highest-quality studies.

Ping Wang (The Fourth Affiliated Hospital of China Medical University, Shenyang, Liaoning) and colleagues say that IC/PBS is “a debilitating bladder dysfunction of unknown etiology” that is diagnosed on the basis of characteristic symptoms.

“The symptoms of IC/PBS overlap with those of OAB, except that bladder pain typically presents in IC/PBS and urgency or urge incontinence presents in patients with OAB”, they write. “As a result, IC/PBS can be diagnosed and treated as OAB. To overcome this problem, a biomarker is needed to differentiate between the two diseases.”

They note that the current evidence is limited, and call for a large, multicentre, randomised controlled trial with long-term follow-up to confirm their findings.

Licensed from medwireNews with permission from Springer Healthcare Ltd. ©Springer Healthcare Ltd. All rights reserved. Neither of these parties endorse or recommend any commercial products, services, or equipment.