Palmar fasciitis and polyarthritis syndrome

Complex Regional Pain Syndrome or Limb Pain: A Plea for a Critical Approach

Most frequently, complex regional pain syndrome (CRPS) develops after a trauma and affects distal parts of the limbs. Early recognition and initiation of adequate treatment is crucial for a favorable outcome. On the other hand, misdiagnosing other disorders as CRPS is detrimental because more appropriate treatment may be withheld from the patients. Despite intensive research, a specific biomarker or paraclinical measure for CRPS diagnosis is still lacking. Instead, clinical criteria approved by the International Association for the Study of Pain (IASP) and latest adapted in 2019 are central for diagnosing CPRS. Thus, the CRPS diagnosis remains challenging with the risk of a “deliberate diagnosis” for unexplained pain, while at the same time a delayed CRPS diagnosis prevents early treatment and full recovery. CRPS is a diagnosis of exclusion. To clinically diagnose CRPS, a vigorous exclusion of “other diseases that would better explain the signs and symptoms” are needed before the patients should be referred to tertiary centers for specific pain treatment. We highlight red flags that suggest “non-CRPS” limb pain despite clinical similarity to CRPS. Clinical and neurological examination and paraclinical evaluation of a probably CRPS patient are summarized. Finally, we pinpoint common differential diagnoses for CRPS. This perspective might help CRPS researchers and caregivers to reach a correct diagnosis and choose the right treatment, regardless whether for CRPS mimics or CRPS itself.

Palmar Fasciitis and Polyarthritis Syndrome: A Rare Paraneoplastic Syndrome in a Patient With Prostate Carcinoma

A 73-year-old patient was seen in our hospital for treatment of metastatic adenocarcinoma of the prostate (pT_1aN₀M_1a R₀, BRCA-2 gene mutation). Prostatectomy and regional radiotherapy were performed and goserelin, a luteinizing hormone-releasing hormone (LHRH) analog, had been started because of disease progression. Castration-resistant progressive disease developed, and enzalutamide was added. A decrease of the prostate-specific antigen (PSA) level was achieved. Before the start of enzalutamide, the patient developed bilateral pain and stiffness of both hands combined with thickening of the hands. The symptoms progressed rapidly to bilateral flexion and extension contractures. The patient became unable to tie his shoelaces and had to use adjusted cutlery to eat. Consultation of the rheumatologist, X-rays, ultrasound and palmar skin biopsy of the hands were performed. The clinical picture resembles descriptions of “palmar fasciitis and polyarthritis syndrome” (PFPAS), a rare paraneoplastic syndrome. Positive effects of immunosuppressive medication have been reported in some cases. In our patient, treatment with oral prednisone (30 mg daily) showed no effect, therefore treatment was switched to methylprednisone pulses and methotrexate. PFPAS is an uncommon paraneoplastic syndrome characterized by rapid onset of bilateral arthritis of the hands, fasciitis of the palms, progressive stiffness and contractures. The scarcity of knowledge about PFPAS makes it difficult to recognize it at an early stage. As a paraneoplastic syndrome, it has been linked to various malignancies. Thus far, PFPAS has been described in only two other cases of prostate cancer.