[Primary meningococcal infection of the knee. A rare cause of septic arthritis]

Neisseria meningitidis serogroup C causing primary polyarthritis in an octogenarian

A man in his 80s presented to the hospital with a 36-hour history of fever, myalgia, bilateral shoulder and right knee pain. Joint fluid aspirates from his shoulders and right knee isolated Gram-negative diplococci. After failing to grow on standard and selective media, Neisseria meningitidis was identified by 16s PCR and subsequently typed as serogroup C. He had no clinical features of meningitis or meningococcaemia. Blood cultures were negative and an EDTA blood sample was negative for meningococcal ctrA gene. Urine PCR was negative for Neisseria gonorrhoeae He was treated successfully with two arthroscopic joint washouts of his right knee, aspirates of both shoulders, 40 days of intravenous ceftriaxone and intensive physiotherapy as both an inpatient and outpatient. In the literature, we have not found any previously documented cases of serogroup C meningococcus causing polyarticular primary septic arthritis in this age group or guidance on duration of antibiotic treatment. Literature on the impact of rehabilitation to baseline function was also found to be lacking. Although rare, primary meningococcal arthritis (PMA) should be considered as a differential diagnosis in cases of acute polyarticular septic arthritis. Polyarticular PMA in older adults may require prolonged rehabilitation before one might expect to return to premorbid function.

Detection of Neisseria meningitidis in a paediatric patient with septic arthritis using multiplexed diagnostic PCR targeting meningitis/encephalitis (ME)

BACKGROUND

Neisseria meningitidis is associated with meningitis and septicemia. Septic meningococcal arthritis is relatively uncommon and its diagnosis associated with clinical and microbiological challenges. Early recognition and treatment is required to prevent joint destruction.

PURPOSE

We describe a case of an eleven-year-old boy with septic arthritis and the first reported use of a multiplexed diagnostic PCR test, capable of simultaneous rapid detection of 14 pathogens directly from CSF samples, to determine presence of N. meningitides in a synovial fluid sample.

RESULTS

In this case, blood cultures and an aspiration of the joint fluid were negative for microbial growth, but leucocytes were present. Analysis of samples using the multiplexed FilmArray^® meningitis/encephalitis panel (MEP) proved positive for N. meningitidis. In parallel, samples forwarded to an accredited reference laboratory confirmed the findings by bacterial 16S rRNA gene amplification and sequencing. Subsequent to these results, empiric treatment with intravenous flucloxacillin was discontinued and oral amoxicillin administered for 1 month. The status of the patient improved with etiology-based antimicrobial therapy.

CONCLUSIONS

This case demonstrates difficulties associated with clinical and microbiological diagnosis of primary septic meningococcal arthritis. We describe the first successful use of the FilmArray^® MEP assay in detection of N. meningitidis in that context.

Neisseria meningitidis Serogroup C Causing Primary Arthritis in a Child: Case Report

INTRODUCTION

Neisseria meningitidis (N. meningitidis) is associated with severe invasive infections such as meningitis and fulminant septicemia. Septic arthritis due to N. meningitidis is rare and bone infections have been reported exceptionally. We report the case of a 1-year old girl who presented with a painful, swollen right knee, accompanied by fever and agitation. Arthrocentesis of the right knee, while patient was under anesthesia, yielded grossly purulent fluid, so we made arthrotomy and drainage. The culture from synovial fluid revealed N. meningitidis, sensitive to Ceftriaxone. The patient received intravenous antibiotherapy with Ceftriaxone. The status of the patient improved after surgical drainage and intravenous antibiotic therapy. She recovered completely after 1 month.

CONCLUSION

This observation illustrates an unusual presentation of invasive meningococcal infection and the early identification of the bacteria, combined with the correct treatment, prevent the complications and even death.