Septic arthritis of the shoulder due toUreaplasma urealyticumafter emergency caesarean section: a case report

Background Ureaplasma urealyticumis an intra-cellular bacterium frequently found colonizing the genital tract. Known complications include localized infections, which can result in premature deliveries. Septic arthritis due toU. urealyticumin healthy patients is exceptionally rare, although opportunistic septic arthritis in agammaglobulinemic patients have been reported. However, there are no reports of septic arthritis due toU. urealyticumfollowing caesarean section or in the post-partum period. Case presentation A 38-year-old immunocompetent woman presented with severe right shoulder pain, 1 month following emergency caesarean section at 26 weeks of gestation for pre-eclampsia and spontaneous placental disruption with an uncomplicated post-operative recovery. Our suspicion of septic arthritis was confirmed with abundant pus following arthrotomy by a delto-pectoral approach. Awaiting culture results, empirical antibiotic treatment with intravenous amoxicilline and clavulanic acid was initiated. In spite of sterile cultures, clinical evolution was unfavorable with persistent pain, inflammation and purulent drainage, requiring two additional surgical debridement and lavage procedures. The 16S ribosomal RNA PCR of the purulent liquid was positive forU. urealyticumat 2.95 x 10(6)copies/ml, specific cultures inoculated a posteriori were positive forU. urealyticum. Levofloxacin and azithromycine antibiotherapy was initiated. Susceptibility testing showed an intermediate sensibility to ciprofloxacin and clarithromycin. The strain was susceptible to doxycycline. Following cessation of breastfeeding, we started antibiotic treatment with doxycycline for 4 weeks. The subsequent course was favorable with an excellent functional and biological outcome. Conclusions We report the first case of septic arthritis due toU. urealyticumafter caesarean section. We hypothesize that the breach of the genital mucosal barrier during the caesarean section led to hematogenous spread resulting in purulent septic arthritis. The initial beta-lactam based antibiotic treatment, initiated for a purulent arthritis, did not provide coverage for cell wall deficient organisms. Detection of 16S rRNA allowed for a correct microbiological diagnosis in a patient with an unexpected clinical course.