Ultrasound diagnosis of pyogenic flexor tenosynovitis in a 9-month-old infant: a rare case report.

Pyogenic flexor tenosynovitis (PFT) is an aggressive infection of the flexor tendon sheath, requiring prompt intervention to minimize adverse outcomes. The diagnosis of pediatric PFT is often delayed due to the variable presence of Kanavel's signs in children and communication difficulties. A 9-month-old male presented to the emergency department with one of four Kanavel signs. The diagnosis of PFT was delayed until ultrasound was used to identify a fluid collection within the flexor tendon sheath. He was successfully treated with surgical debridement and antibiotic therapy, achieving full recovery by 6-month follow-up. This represents the youngest reported case of PFT. Difficulties with communication and physical exam as well as the variability of Kanavel's signs in young children can delay the diagnosis of pediatric PFT. Ultrasound can be a useful adjunct when clinical history and exam are equivocal, especially in children who present prior to language acquisition.

Hemolysis Is a Diagnostic Adjuvant for Propionibacterium acnes Orthopaedic Shoulder Infections.

INTRODUCTION: The purpose of this study was to further evaluate the pathogenicity of hemolytic and nonhemolytic phenotypes of Propionibacterium acnes (P acnes) isolates from shoulders of orthopaedic patients. METHODS: Thirty-one patient records were reviewed, which had a positive P acnes shoulder culture from joint aspiration fluid and/or intraoperative tissues for demographics, clinical course, culture, and laboratory data. Patients were categorized as definite infection, probable infection, or probable contaminant. Antibiotic resistance patterns and hemolysis characteristics were subsequently analyzed. RESULTS: Hemolysis demonstrated 100% specificity with a positive predictive value of 100% and 80% sensitivity with a negative predictive value of 73% for determining definite and probable infections. Hundred percent of the patients in the hemolytic group and only 27% of patients in the nonhemolytic group were classified as infected. Presenting inflammatory markers were markedly higher in the hemolytic group. Clindamycin resistance was found in 31% of the hemolytic strains, whereas no antibiotic resistance was observed in the nonhemolytic group. CONCLUSION: Hemolytic strains of P acnes exhibit enhanced pathogenicity to their host by eliciting a more prominent systemic inflammatory response, increased antibiotic resistance, and a more challenging clinical course. Hemolysis may serve as a specific marker for assisting in diagnosing true infection with P acnes. LEVEL OF EVIDENCE: Level III retrospective comparative study.

Propionibacterium acnes Susceptibility and Correlation with Hemolytic Phenotype.

BACKGROUND: Many studies have noted an increase in the number of recognized cases of invasive infections due to Propionibacterium acnes, especially after shoulder replacement surgery. The increase in the number of recognized cases of P. acnes, a nonspore-forming, anaerobic, Gram-positive organism, appears due to both an increase in the number of shoulder operations being performed and more specimens being sent for anaerobic cultures. Nevertheless, the optimal surgical and antibiotic management of P. acnes remains controversial. METHODS: We tested the susceptibility of 106 P. acnes strains from sterile body sites collected at the Erie County Medical Center between 2012 and 2015, using Etest gradient antibiotic strips. RESULTS: P. acnes is very susceptible to the penicillins and the first-generation cephalosporins. We noted an association between hemolytic phenotype on Brucella Blood Agar and clindamycin resistance. CONCLUSIONS: Antimicrobial susceptibility testing of P. acnes should no longer just be confined to the research laboratory but expanded and incorporated into routine microbiological evaluation of P. acnes. This would improve patient care as well as help clarify the relationship between hemolysis and clindamycin resistance.