11institutetext: Knowledge-based Systems and Document Processing Research Group Faculty of Computer Science Otto-von-Guericke-University Magdeburg 11email: katrin.krieger@ovgu.de
Discussion:
Septic arthritis among individuals who use intravenous (IV), or intramuscular (IM) tramadol can be a serious complication, especially considering the potential for introducing pathogens into the bloodstream or deep tissues during drug administration. Studies have shown a strong association between the practice of injecting drugs and the incidence of septic arthritis caused by Staphylococcus aureus, including MRSA strains. Individuals with a history of injecting drugs have been found to be at higher odds of developing septic arthritis due to S. aureus, highlighting the role of this risk factor in the pathogenesis of the infection6.
In this case report, the patient had MRSA-positive sternoclavicular septic arthritis following repeated intravenous and intramuscular tramadol and multivitamin injections. Sternoclavicular joint (SCJ) infection is an uncommon condition, accounting for only 0.5% - 1.0% of all septic arthritis cases and less than 0.5% of septic arthritis in healthy patients7.
The proximity of the sternoclavicular joint to the mediastinum complicates differentiating between mediastinal masses and malignancies. A similar case was reported of septic arthritis being initially mistaken for malignancy, but that case involved Methicillin-Sensitive Staphylococcus aureus (MSSA) and rhGH (Recombinant human growth hormone) abuse, which could have influenced the infection’s development5. In contrast, our case involved Methicillin-Resistant Staphylococcus aureus (MRSA) and tramadol/multivitamin abuse, with no apparent role of the drugs in infection pathogenesis. Our patient was managed with embolization, long-term IV antibiotics, and physiotherapy, whereas the above-mentioned patient required multiple surgeries and extended antibiotics due to an inadequate initial response.
We believe that the spread of infection to the sternoclavicular joint in particular was due to the injections being frequently administered in the deltoid region. This is supported by a study that discussed the possibility of bacteria entering the sternoclavicular joint from adjacent veins after the injection of contaminated drugs into the upper extremity8.
Our case of sternoclavicular septic arthritis presenting as a mediastinal malignancy contributes to the literature by highlighting the diagnostic challenges when infections mimic malignancies. It demonstrates the importance of distinguishing between severe infections and cancer through comprehensive diagnostic approaches and underscores the effectiveness of advanced imaging and surgical interventions, such as embolization of a pseudoaneurysm. The case also illustrates the need for tailored treatment strategies and interdisciplinary collaboration in managing complex infections, providing practical insights into clinical decision-making and resource considerations.
The case has several limitations: it focuses on immediate treatment without long-term follow-up on recurrence or outcomes; advanced diagnostic and therapeutic techniques used may not be available in low-resource settings; the patient’s multiple pre-existing conditions may have complicated the infection’s presentation and management; and the initial mimicry of a malignancy required extensive and potentially delayed diagnostic workup, which may not be feasible in all clinical settings.