A rare case of Prosthetic Joint Infection associated with Coxiella burnetii

Hip periprosthetic joint infection due to Coxiella burnetii in an adult male

Coxiella burnetii is an obligate intracellular Gram-negative bacterium. "Query fever" (Q fever) first described in 1939 is a disease caused by Coxiella burnetii. This bacterium infects animals including goats, sheep, and cattle, and has been recognized as a pathogen causing acute illness in humans. A patient living on a farm with a history of a right total hip arthroplasty presented with right hip pain. Arthrocentesis revealed a total nucleated count of 4288 (93% neutrophils), however his synovial fluid culture remained negative. His Q fever phase I IgG and phase II IgG were elevated at 1:4096 and 1:2048, respectively. He underwent incision and drainage with exchange of the femoral head and acetabular component, with retention of the femoral stem. PCR of tissue samples returned positive for Coxiella burnettii. He was diagnosed with a persistent localized prosthetic joint infection (PJI) of the right hip. Coxiella burnetii PJI is a rare but increasingly recognized form of persistent localized Q fever infection. Q fever should be considered in the differential diagnosis of culture-negative PJI, especially among patients with exposure to sheep, goats, or cattle. Initial screening for Coxiella burnetii includes serology, but tissue PCR and immunohistochemical staining may be obtained to confirm joint infection.

Diagnosis of Coxiella burnetii Prosthetic Joint Infection Using mNGS and ptNGS: A Case Report and Literature Review

BACKGROUND

Coxiella burnetii (C. burnetii) is the causative agent of Q fever and is found worldwide; however, prosthetic joint infections caused by C. burnetii are rarely seen. Because of advances in molecular diagnostic techniques, prosthetic joint infection (PJI) caused by C. burnetii can now be diagnosed.

CASE PRESENTATION

A 77-year-old male who had undergone total knee arthroplasty had a displaced prosthesis and periprosthetic osteolysis; he had no obvious signs of infection, and microbiological culture was negative. However, C. burnetii was detected by metagenomic next-generation sequencing (mNGS) and pathogen-targeted next-generation sequencing (ptNGS). Finally, polymerase chain reaction (PCR) confirmed the diagnosis of C. burnetii prosthetic joint infection (PJI). After revision surgery (one-stage revision) and oral antibiotics (doxycycline and moxifloxacin hydrochloride), the patient's symptoms disappeared, and he regained the ability to walk. During the 6-month follow-up, the patient's knee showed no signs of swelling, pain or the recurrence of infection, and he experienced no significant complications. We also present a review of the literature for other cases of C. burnetii PJI.

CONCLUSIONS

The symptoms of C. burnetii PJI may be different from those of Q fever, which may lead to misdiagnosis. mNGS and ptNGS may be helpful for the identification of C. burnetii. Once the diagnosis of C. burnetii PJI is confirmed, doxycycline in combination with a fluoroquinolone can be effectively administered after revision surgery.

Diagnosis of Coxiella burnetii infection via metagenomic next-generation sequencing: a case report

BACKGROUND

Coxiella burnetii, the etiologic agent of Q fever, is mainly responsible for endocardite. But there are only a few cases of Coxiella burnetii-caused wound infection have been published, because the pathogen is very difficult to isolate using conventional culture methods.

CASE PRESENTATIONS

A 76-year-old man, underwent endovascular repair of ruptured left iliac aneurysm plus abdominal aortic aneurysm under general anesthesia in 2018. Left iliac fossa mass resection was performed in 2020. After operation, the wound in the left iliac fossa was repeatedly ruptured and not healing. We used the wound tissue to perform the Metagenomics next-generation sequencing (mNGS), Coxiella burnetii was detected. Sanger sequencing and serologic verification of Coxiella burnetii all showed positive results.

CONCLUSIONS

This study proved that mNGS was an effective method to detect clinically unexplained infections, and showed the ability of pathogen identification with high sensitivity and accuracy.

Meta-analysis of synovial fluid polymerase chain reaction for diagnosing periprosthetic hip and knee infection

Background and objective

The purpose of this study was to estimate the diagnostic performance of synovial fluid polymerase chain reaction (PCR) in periprosthetic hip and knee infection, and whether synovial fluid PCR has greater diagnostic significance than conventional methods.

Methods

The literature databases PubMed, Scopus, and the Web of Science were searched for English articles describing periprosthetic joint infection (PJI) diagnosis by synovial fluid PCR. Articles were limited to the period between January 1990 and December 2019. Subsequently, conventional methods that were used on at least two occasions were included for further analysis. Data analysis was performed using the Meta-DiSc and Stata software.

Results

Eleven studies with 1360 cases were included in the meta-analysis. The pooled sensitivity, specificity, and diagnostic odds ratio (DOR) of synovial fluid PCR were 0.70 (95% CI 0.66–0.74), 0.92 (95% CI 0.90–0.93), and 37.4 (95% CI 17.77–78.74), respectively.

Conclusions

Synovial fluid PCR provides an effective tool for rapid diagnosis of PJI, and also in the early stages of culture-negative bacterial infections.

Reactivation of Q fever: case report of osteoarticular infection developing at the site of a soft tissue injury

Coxiella burnetii, the causative agent of Q fever, is known to cause acute and persistent infection, but reactivation of infection is rarely reported. This case demonstrates reactivation of a distant, untreated Q fever infection after a relatively innocuous soft tissue injury in an adjacent joint without pre-existing pathology. A 52-year-old male abbatoir worker sustained an adductor muscle tear in a workplace injury. He was unable to walk thereafter, and developed a chronic, progressive, destructive septic arthritis of the adjacent hip with surrounding osteomyelitis of the femur and acetabulum. He had evidence of prior Q fever infection, with a positive skin test and serology 15 years beforehand. He was diagnosed with chronic osteoarticular Q fever on the basis of markedly elevated phase I antibodies, and symptomatic and serological response to prolonged antibiotic treatment with doxycycline and hydroxychloroquine. He required a two-stage hip arthroplasty. This case illustrates reactivation of latent C. burnetii infection at the site of a soft tissue injury. Clinicians need to be aware of this possibility in patients with previous Q fever infection, and in the setting of undiagnosed osteoarticular pathology following soft tissue injury.