Abstract Background/Aims A 79-year-old lady of White British ethnicity developed a sudden right-sided tongue swelling resulting in dysphasia and dysphagia. She had only been on ACE inhibitors for hypertension, which were stopped to ensure this was not angioedema. There was no neck pain, fever or history of arthritis in other joints. Neck movements and other cranial nerves examination were normal. Methods Case report detailing the presentation and management. Results Bloods showed raised rheumatoid factor at 276IU/mL and uric acid 359micromol/L. CRP, anti-CCP antibodies and ANA were normal. MRI neck reported pannus formation abutting the hypoglossal nerve, causing acute hypoglossal nerve palsy. CT spine reported active synovitic lesion distorting medulla, in continuity with pannus formation at C1-C2. This was consistent with calcium pyrophosphate crystal deposition. Temporal artery ultrasound was normal. Local steroid injection and surgery were deemed high risk. Hence, oral prednisolone 30mg with colchicine 500mcg daily was started. However, the symptoms did not change. Prednisolone was then stopped. MRI at 5 months showed persistent crowned dens with new displacement of right intracranial vertebral artery. She was then given an intramuscular steroid of 120mg. MRI at 8 months showed no improvement. Her colchicine was doubled and low dose prednisolone re-started with slow weaning. At 12 months, she developed occipital pain on head flexion which improved with a further increase in Colchicine at 500mcg in the morning and 1mg at night. She has been referred for an occipital nerve block. Conclusion Crowned dens syndrome (CDS) is an uncommon manifestation of calciumpyrophosphate dihydrate (CPPD) or hydroxyapatite crystal deposition around the odontoid process. It predominantly affects older females and presents with neck pain, stiffness, and restriction, occasionally fever and raised inflammatory markers. Diagnosis is best established with non-contrast CT of C1-C2 with pathognomonic crown or halo of peri-odontoid calcifications. MRI is less sensitive. Dual-energy CT characterises crystal type. CDS is frequently misdiagnosed as meningitis or giant-cell arteritis. Most patients respond rapidly to NSAIDs or a short corticosteroid course, whereas surgical decompression and internal fixation are reserved for severe or refractory neurological compromise. Persistent headaches and upper cervical radiculopathy are rare. In exceptional cases, quadriplegia due to cervico-medullary compression can occur. While cranial nerve involvement is rarely seen in typical CDS, retro-odontoid CPPD lesions can occasionally extend to the brainstem. A published case describes a CPPD pseudotumour rupturing into the brainstem with acute cranial neuropathy, illustrating a plausible mechanism for this complication. These reports broaden the recognised neurological spectrum of CDS and emphasise the importance of timely CT diagnosis and targeted management. Our patient uniquely had a cranial nerve palsy without initial neck pain or fever. Her lack of response (clinical and radiological) and partial and delayed response to colchicine makes a unique and challenging presentation. Disclosure K. Sharma: None. H. Irvine: None. U. Ahmed: None. M. Iftikhar: None. A. Ahmed: None.
Sharma et al. (2026) studied this question.