Clinical trial NCT05678127: A Pilot Study to Explore the Use of Skin Biopsy as Diagnostic Tool in Anterior Cutaneous Nerve Entrapment Syndrome (ACNES)
Official title: Skin Biopsy as Diagnostic Tool in Anterior Cutaneous Nerve Entrapment Syndrome (ACNES): A Pilot Study
Study type: INTERVENTIONAL
Overall status: UNKNOWN
Phase: NA
Conditions: Anterior Cutaneous Nerve Entrapment Syndrome
Nerve Entrapment Syndrome
Chronic Pain Syndrome
Diagnosis
Keywords: Diagnostic test for ACNES
Intraepidermal nerve fibre density (IENFD)
Lead sponsor: Maxima Medical Center
Sponsor class: OTHER
First posted: 2023-01-10
Enrollment: 12
Sex: ALL
Minimum age (years): 21
Maximum age (years): 50
Standard ages: ADULT
Accepts healthy volunteers: no
Allocation: NA
Intervention model: SINGLE_GROUP
Intervention model description: Skin biopsies will be performed on patients with an unilateral ACNES. Biopsies will be taken at the triggerpoint (affected side) and contralateral, non-affected side of the abdominal wall.

Affected vs non-affected will be compared. The non-affected side serves as control.
Primary purpose: DIAGNOSTIC

Brief summary: ACNES is a neuropathic pain condition of the abdominal wall. It is a clinical diagnosis based on patient's history and physical examination. No diagnostic test is available to confirm the diagnosis.

This pilot study will determine if skin biopsies can be used as diagnostic test. Two 3mm biopsies will be taken and used to count the small nerve fibres in the skin. The number of small nerve fibres of the painful skin will be compared to non-painful skin. Skin biopsy and small fibre nerve count is already used as diagnostic test in patients with small-fibre neuropathy.

The investigators hypothesize that patients with ACNES will have a reduced number of small nerve fibres in the affected skin, compared to the non-affected skin.


Eligibility criteria: Inclusion Criteria:

* Duration of pain \>3 months
* Newly diagnosed unilateral ACNES
* Fully completed intake questionnaire
* Obtained written informed consent

Exclusion Criteria:

* Inability to understand Dutch language
* Bilateral ACNES
* Previously administered injections with corticosteroids at trigger point (injection with a local anaesthetic is allowed)
* Previous Pulsed Radiofrequency (PRF)-treatment at trigger point
* History of open abdominal surgery
* History of neurectomy
* Known neuromuscular or neurodegenerative disease
* Antiplatelet or anticoagulants use or known coagulation disorders
* Disorder known to cause a reduced IENFD;

  * Diabetes
  * Hypothyroidism
  * Renal failure
  * Vitamin B12 deficiency
  * Monoclonal gammopathy
  * Alcohol abuse (\>5 IU a day)
  * Malignancies
  * Medication that cause neuropathy (for example chemotherapy)

Primary outcomes:
measure: Intraepidermal Nerve Fibre density (IENFD)
timeFrame: Both biopsies will be taken at the same time, as their difference will be studied. The biopsies will be taken at the second outpatient visit, 2 or 3 weeks after the first visit, just after the second triggger point injection (standard of care).
Secondary outcomes:
measure: Pain score
timeFrame: Assessed at first outpatient visit, used as baseline data.
measure: Duration of pain
timeFrame: Assessed at first outpatient visit, used as baseline data.
measure: Treatment response
timeFrame: Treatment response will be assessed 2 to 6 weeks after each treatment (trigger point injections, PRF and neurectomy), as standard of care.
Other outcomes:
Locations:
city: Veldhoven
country: Netherlands
facility: Maxima Medical Center
Study officials:
affiliation: Maxima Medical Center
name: Rudi Roumen, MD, PhD
role: PRINCIPAL_INVESTIGATOR
References: