# Polymyalgia Rheumatica Mimicking Infection and Malignancy: A Diagnostic Challenge Ruled Out by PET-CT

## TL;DR

This paper discusses a case where polymyalgia rheumatica was mistaken for infection or cancer, but a PET-CT scan helped confirm the correct diagnosis.

## Contribution

The paper highlights the diagnostic utility of PET-CT in atypical cases of polymyalgia rheumatica.

## Key findings

- PET-CT helped rule out malignancy and infection in a patient with polymyalgia rheumatica.
- A rapid response to corticosteroid therapy confirmed the PMR diagnosis.
- PET-CT can reduce unnecessary invasive investigations in atypical PMR cases.

## Abstract

Polymyalgia rheumatica (PMR) is an inflammatory disorder affecting older adults, typically presenting with pain and stiffness in the shoulder and pelvic girdle. The clinical features may overlap with infection or malignancy, often leading to delayed treatment and extensive, sometimes unnecessary, investigations. We present a case of an elderly patient with prolonged shoulder pain and elevated inflammatory markers who underwent a comprehensive evaluation. MRI of the shoulder and PET-CT were performed to exclude alternative diagnoses. The imaging findings, combined with the clinical presentation and a rapid response to corticosteroid therapy, confirmed the diagnosis of PMR. This case underscores the pivotal role of PET-CT in the diagnostic workup of atypical PMR, facilitating the exclusion of sinister pathologies such as malignancy or infection, guiding clinical decision-making, and reducing the need for unnecessary invasive investigations.