Fever of unknown origin following parathyroidectomy prior to onset of typical polymyalgia rheumatica symptoms: a case report

Abstract

Polymyalgia rheumatica (PMR) is a disease commonly seen in elderly individuals, however, the etiology has not been reported. Typical clinical features include bilateral shoulder pain and morning stiffness, while serologic autoantibody test findings are negative. Approximately 40%–50% of affected patients present with low-grade fever, fatigue, and appetite loss, which we often experience in the field of general medicine, and thus, the condition should not be given low priority. However, knowledge regarding such constitutional manifestations is also limited. We encountered an elderly woman with a fever of unknown origin that developed following a parathyroidectomy for a single parathyroid adenoma, after which severe shoulder pain and morning stiffness emerged, leading to a diagnosis of PMR. The fever developed several days prior to appearance of severe pain, which is an uncommon presentation in PMR cases. Our patient had low-grade inflammation without pyrexia prior to the surgery, which might have been an important reason for the accelerated immoderate immune activation leading to PMR induced by surgery in this case. Furthermore, she was infected with the influenza A virus 3 weeks before coming to us. Some reports have suggested a relationship between the influenza virus or vaccine and PMR. It is difficult to conclude regarding the definite trigger in our patient, though the details of this case should be helpful for a better understanding of the disease.

Fever Correlation with Erythrocyte Sedimentation Rate (ESR) and C-Reactive Protein (CRP) Concentrations in Patients with Isolated Polymyalgia Rheumatica (PMR): A Retrospective Comparison Study between Hospital and Out-of-Hospital Local Registries

“…Indeed, in these patients, fever is thought to be caused by some cytokines, most notably interleukin-6 and interleukin-1 (IL-6 and IL-1), strongly associated with a CRP increase. On the other hand, fever may itself induce a CRP increase [ 23 , 24 ]. The Belgian researchers suggested that a long delay to a PMR diagnosis might explain this discrepancy possibly caused by laboratory alterations (among these, anemia of chronic disease type) that can influence only ESR [ 22 ].…”