Total hip arthroplasty infection caused by an unusual organism, Salmonella; its successful management and literature review

Prosthetic hip infection due to Salmonella enterica serovar Enteritidis

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Prosthetic joint infection (PJI) due to Salmonella spp. is uncommon, with an estimated prevalence of <0.3 % of all PJI.

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Salmonella enterica serovar Enteritidis and Salmonella enterica serovar Typhimurium are the most common isolates causing PJI.

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Risk factors include malignancy, hemoglobinopathies, diabetes mellitus, HIV/AIDS, alcohol dependency and immunosuppressed state.

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PJI due to Salmonella spp. can occur without significant preceding gastrointestinal symptoms of infection.

Prosthetic joint infection (PJI) is a serious complication of prosthetic joint implantation with a prevalence of about 1–2 % of all prosthetic joint surgeries. While Staphylococcus spp. are the most common organisms isolated, Salmonella spp. are a rare cause of PJI (estimated prevalence < 0.3 %). We present a case of a 62-year-old patient with a history of previous joint trauma complicated by osteonecrosis, infection and chronic alcohol abuse with late hematogenous prosthetic hip infection due to Salmonella enterica serovar Enteritidis. PJI due to Salmonella spp. should be considered in the differential diagnosis when a patient has risk factors such as malignancy, hemoglobinopathies, diabetes mellitus, human immunodeficiency virus/acquired immunodeficiency syndrome, alcohol dependency or immunosuppressed state, even without significant preceding gastrointestinal symptoms. Our patient had a few of these risk factors and required surgical debridement in addition to antimicrobials for treatment of his PJI.

Infected Hematoma After Endoscopic Sciatic Nerve Decompression

We present a 24-year-old male who developed an infected hematoma that resulted in sciatic nerve injury after he underwent an endoscopic sciatic nerve decompression. He underwent urgent hematoma evacuation and cultures speciated as Salmonella. At 4 months’ follow-up, the patient’s nerve had improved motor and sensory function. This case highlights the importance of obtaining appropriate hemostasis at the end of an endoscopic sciatic nerve decompression.

From Crosstalk between Immune and Bone Cells to Bone Erosion in Infection

Bone infection and inflammation leads to the infiltration of immune cells at the site of infection, where they modulate the differentiation and function of osteoclasts and osteoblasts by the secretion of various cytokines and signal mediators. In recent years, there has been a tremendous effort to understand the cells involved in these interactions and the complex pathways of signal transduction and their ultimate effect on bone metabolism. These crosstalk mechanisms between the bone and immune system finally emerged, forming a new field of research called osteoimmunology. Diseases falling into the category of osteoimmunology, such as osteoporosis, periodontitis, and bone infections are considered to have a significant implication in mortality and morbidity of patients, along with affecting their quality of life. There is a much-needed research focus in this new field, as the reported data on the immunomodulation of immune cells and their signaling pathways seems to have promising therapeutic benefits for patients.