# A Case of Complex Regional Pain Syndrome With Hypermobile Ehlers-Danlos Syndrome and Mast Cell Activation Syndrome: The Role of Unconventional Therapies

**Authors:** Zian Shabbir, Layla Mazdeyasnan, Mary McLain

PMC · DOI: 10.7759/cureus.87898 · Cureus · 2025-07-14

## TL;DR

A patient with complex chronic pain conditions showed some improvement with unconventional treatments targeting mast cell inflammation.

## Contribution

This case study explores novel mast cell-targeted therapies for CRPS linked to hEDS and MCAS.

## Key findings

- Montelukast and cromolyn sodium showed initial pain improvement in a complex CRPS case.
- A digestive regimen with anti-inflammatory supplements was trialed alongside mast cell stabilizers.
- A subjective narrative scoring system better captured the patient's fluctuating symptoms than traditional pain scales.

## Abstract

Complex regional pain syndrome (CRPS) type 2 is a chronic pain condition that develops after a nerve injury and is characterized by severe pain, allodynia, and functional impairments. Ehlers-Danlos syndrome hypermobility type (hEDS) and mast cell activation syndrome (MCAS) are connective tissue and inflammatory disorders that may contribute to the development of CRPS. Despite various treatment approaches, effective pain management remains a challenge, particularly in complex cases involving underlying genetic predispositions. We report the case of a 42-year-old female with a history of CRPS type 2, who was recently diagnosed with hEDS and had a family history of MCAS. Her clinical symptoms of chronic pain and gastrointestinal (GI) disturbances were unresponsive to typical therapeutic interventions. She was being managed with multiple medications. With this thought in mind, montelukast, a leukotriene receptor antagonist, was introduced, and the patient reported an initial improvement in pain. Cromolyn sodium, a mast cell stabilizer, was also added to her treatment regimen to further target her pain exacerbation. Finally, an anti-inflammatory focused GI regimen including betaine HCl, quercetin with bromelain, and other digestive enzymes was trialed. Her progress was monitored using a pain scale over the next six months. However, due to declining health, a subjective narrative scoring system replaced the Visual Analog Scale to represent her fluctuating and multifaceted symptom experience better. The relationship between hEDS, MCAS, and CRPS suggests a multifactorial pathogenesis involving connective tissue fragility, mast cell dysregulation, and neurogenic inflammation. Montelukast, cromolyn sodium, and GI supplementation represent potential therapeutic interventions for managing patients with CRPS linked to MCAS. These treatments offer a novel approach by targeting mast cell-mediated inflammation. This case emphasizes the need for further research into the role of mast cell stabilization in CRPS treatment to improve patient outcomes.

## Linked entities

- **Chemicals:** montelukast (PubChem CID 5281040), cromolyn sodium (PubChem CID 27503), betaine HCl (PubChem CID 11545), quercetin (PubChem CID 5280343)
- **Diseases:** Complex Regional Pain Syndrome (MONDO:0019369), Ehlers-Danlos syndrome hypermobility type (MONDO:0007523), mast cell activation syndrome (MONDO:0100004)

## Full-text entities

- **Genes:** DPP4 (dipeptidyl peptidase 4) [NCBI Gene 1803] {aka ADABP, ADCP2, CD26, DPPIV, TP103}, TAC1 (tachykinin precursor 1) [NCBI Gene 6863] {aka Hs.2563, NK2, NKNA, NPK, TAC2}
- **Diseases:** injury (MESH:D014947), neuropathic disorder (MESH:D009437), causalgia (MESH:D002422), pain syndromes (MESH:C538101), excessive flexibility (MESH:D005413), dysmotility (MESH:D015154), connective tissue disorders (MESH:D003240), Ehlers-Danlos syndrome hypermobility type (MESH:C536196), edema (MESH:D004487), MCAS (MESH:D000090267), nerve injury (MESH:D000080902), pain (MESH:D010146), fatigue (MESH:D005221), pyogenic papules of the heel (MESH:C563167), syndrome (MESH:D013577), impaired mobility (MESH:D014086), tissue fragility (MESH:D005600), neuropsychiatric (MESH:C000631768), neuroinflammatory (MESH:D000090862), anxiety (MESH:D001007), postural orthostatic tachycardia syndrome (MESH:D054972), autonomic dysfunction (MESH:D001342), malabsorption (MESH:D008286), nausea (MESH:D009325), Hypermobile Ehlers-Danlos Syndrome (MESH:D004535), GI (MESH:D005767), diarrhea (MESH:D003967), constipation (MESH:D003248), back pain (MESH:D001416), allodynia (MESH:D006930), weight loss (MESH:D015431), MCAS disorder (MESH:D000090362), hypersensitivity (MESH:D004342), joint hypermobility (MESH:D007593), skin hyperextensibility (MESH:D012871), neurogenic inflammation (MESH:D020078), chronic pain (MESH:D059350), Inflammation (MESH:D007249), vomiting (MESH:D014839), CRPS (MESH:D020918), shoulder dislocation (MESH:D012783), depression (MESH:D003866), joint dislocations (MESH:D004204), acute and chronic pain (MESH:D059787), hypochlorhydria (MESH:D000126)
- **Chemicals:** gabapentin (MESH:D000077206), lidocaine (MESH:D008012), leukotriene (MESH:D015289), serotonin-norepinephrine re-uptake inhibitor (-), Cromolyn Sodium (MESH:D004205), ibuprofen (MESH:D007052), ondansetron (MESH:D017294), hydrocodone (MESH:D006853), baclofen (MESH:D001418), GABA (MESH:D005680), histamine (MESH:D006632), propranolol (MESH:D011433), carbohydrates (MESH:D002241), Quercetin (MESH:D011794), lorazepam (MESH:D008140), Betaine HCl (MESH:D001622), duloxetine (MESH:D000068736), acetaminophen (MESH:D000082), Montelukast (MESH:C093875)
- **Species:** Homo sapiens (human, species) [taxon 9606], Rattus norvegicus (brown rat, species) [taxon 10116]

## Full text

_Full body text omitted from this summary view._ Fetch the complete paper as Markdown: https://tomesphere.com/paper/PMC12346194/full.md

## Figures

2 figures with captions in the complete paper: https://tomesphere.com/paper/PMC12346194/full.md

## References

20 references — full list in the complete paper: https://tomesphere.com/paper/PMC12346194/full.md

---
Source: https://tomesphere.com/paper/PMC12346194