Case Presentation:
This is a 77/F with Diabetes Mellitus, Hypertension and severe osteoarthritis who was admitted with 1 day history of mental status change, headache and neck pain with progressive pain in her hands, wrist and knee. Vitals signs revealed fever to 103F, BP 142/72, HR 72 and RR 16. Patient was lethargic but arousable, oriented only to self, unsure of year or place or why she was in the hospital. Neck was tender to palpation with decreased range of motion. There was synovitis in her left 2/3 proximal interphalangeal joint, bilateral wrists, right shoulder and left knee. A CT Brain was negative for any acute intracranial process. Labs demonstrated a WBC 15.61 TH/UL (79.8% PMNS) and creatinine of 1.6 mg/dL from a baseline of 0.73mg/dL. Urine toxicology screen was negative and urinalysis and chest xray did not show any evidence of infection. A lumbar puncture was performed and the patient was started on intravenous fluids with 0.9% normal saline and empiric meningitis treatment with Vancomycin, Ceftriaxone and Ampicillin. Despite treatment, patient remained febrile with continued alteration of mental status. CSF fluid results showed WBC: 58 with 77% neutrophils, Protein: 43, Glucose: 95. At 48 hours, CSF gram stain and cultures remained negative along with HSV PCR, cryptococcal antigen, and enterovirus PCR. MRI brain and spine were then done, which showed fluid in the facet joints at multiple levels and mild focal dural thickening enhancement at the C5-C6 level. By this time, acute polyarticular synovitis most consistent with crystal deposition disease was considered as the patient was not getting better with antibiotics. A CT scan of the spine showed ligamentous calcifications at the central C1-C2 articulation, attributed to calcium pyrophosphate deposition. A left knee aspiration was performed and this revealed WBC 10,400 /mm3 with 95% polys and intracellular CPPD crystals. Uric acid was normal, ESR and CRP were markedly elevated and synovial fluid cultures returned negative. Left knee xray showed CPPD arthropathy. Prednisone was started at a dose of 20mg PO daily. After just a single dose of prednisone, the patient’s pain got better and mental status started to improve. Antibiotics were subsequently discontinued and she was discharged on a steroid taper.
Discussion:
Calcium pyrophosphate dehydrate deposition disease occurs frequently in the cartilage, joint capsule, synovium, bursae, tendons, and ligaments. It can also affect facet joints, the ligamentum flavum, or other tissues in proximity to the spinal cana. CPPD most commonly occurs at the knee, elbow, wrist, hip and shoulder joints. It is rarely known to affect the spine such as in this case, and when it does, patients can be misdiagnosed as meningitis. The term ‘Crowned dens syndrome’ is an underrecognized clinical and radiological disease characterized by acute neck pain ascribed to CPPD deposits and calcification surrounding the odontoid process. Imaging studies with computed tomography scan and magnetic resonance, focusing on C1 and C2, are complementary and polarized-light microscopy examination are utilized to aid in the diagnosis of this disease.
Conclusions: Atyical presentation of CPPD crystal deposition in the cervical spine can be misleading but it should be recognized as a rare but important mimic for meningitis. There are very few cases reported in literature; hence the need for further research to obtain a better understanding of this disease entity. Steroids should be considered without delay for treatment in the absence of active infection.