Periprosthetic joint infection:A South African perspective.

BACKGROUND: South African data on the bacteriology and sensitivity profile of periprosthetic joint infection is lacking.  Current regimens for systemic and local antibiotic therapy are based on international literature. These regimens are different for the United States of America and Europe and might thus not be relevant to South Africa. OBJECTIVES: To determine the characteristics of periprosthetic joint infection in a South African clinical setting by identifying the most common organisms cultured and establishing their antibiotic sensitivities in order to propose the most appropriate empiric antibiotic treatment regimen. In the case of two-stage revision procedures, we aim to compare the organisms cultured during the first stage versus organisms cultured during the second stage in second-stage procedures that had positive cultures.  Furthermore, in these culture-positive second-stage procedures we aim to correlate the bacterial culture with the erythrocyte sedimentation rate/ C-reactive protein result. METHODS: We performed a retrospective cross-sectional study looking at all hip and knee periprosthetic joint infections in patients 18 years and older, treated at a government institution and a private revision practice in Johannesburg, South Africa between January 2015 and March 2020. Data were collected from the Charlotte Maxeke Johannesburg Academic Hospital hip and knee and the Johannesburg Orthopaedic hip and knee databanks. RESULTS: We included 69 patients whom underwent 101procedures relating to periprosthetic joint infection. Positive cultures were found in 63 samples, 81 different organisms were identified. The most common organisms cultured were Staphylococcus aureus (n = 16, 19.8%) and Coagulase negative Staphylococcus (n = 16, 19.8%), followed by Streptococci species (n = 11, 13.6%).  The positive yield in our cohort was 62.4% (n = 63). A polymicrobial growth was found in 19% (n = 12) of the culture positive specimens. Of all the microorganisms cultured, 59.2% (n = 48) were Gram-positive versus 35.8% (n = 29) Gram-negative. The remainder were fungal and anaerobic organisms at 2.5% (n = 2) each. Gram-positive cultures displayed 100% sensitivity to Vancomycin and Linezolid, whereas Gram-negative organisms displayed 82% sensitivity towards Gentamycin and 89% sensitivity towards Meropenem respectively. CONCLUSION: Our study identifies the bacteriology of periprosthetic joint infections and their sensitivities in a South African setting. We recommend that empiric antibiotic-loaded cement spacers and systemic antibiotic regimens should consist of Meropenem or Gentamycin; Vancomycin and Rifampicin to achieve the broadest spectrum of coverage and most likely success in eradicating infection.

The effect of time to surgery on outcomes and complication rates following total hip arthroplasty for fractured neck of femur.

INTRODUCTION: Total hip arthroplasty is recommended for elderly patients with fractured neck of femur who are independently mobile, have few co-morbidities and are not cognitively impaired. Providing a daily total hip arthroplasty service is challenging for some units in the UK and considering that these patients may be physiologically distinct from the average hip fracture patient, loss of the best practice tariff as a result of surgical delay may be unjustified. The aim of this study was to determine whether time to surgical intervention for patients eligible for total hip arthroplasty had a negative impact on patient complications, length of stay and functional outcomes. METHODS: All patients undergoing total hip arthroplasty for fractured neck of femur at our institution over a ten-year period were identified. Complications and functional outcomes were compared between patients receiving total hip arthroplasty before and after 36 hours. RESULTS: Of 112 consecutive patients undergoing total hip arthroplasty, 70 responded to a questionnaire or telephone consultation. Four patients were excluded owing to delayed presentation, the presence of advanced rheumatoid arthritis or a pathological fracture. Two-thirds (64%) of the remaining 66 patients underwent surgery within 36 hours of presentation. There were no significant differences between the groups of patients receiving surgery before or after 36 hours with regard to postoperative length of stay, complications, Oxford hip scores or visual analogue scale scores for state of health. CONCLUSIONS: Delaying surgery for patients eligible for total hip arthroplasty as per the National Institute for Health and Care Excellence guidelines is justified and should not incur loss of the best practice tariff.

Surgery for portal hypertension in children: A 12-year review.

BACKGROUND: Portal hypertension is a common and potentially devastating condition in children. Notwithstanding advances in the nonsurgical management of portal hypertension, surgery remains an important treatment modality in select patients. We report here on our experience in the past 12 years. OBJECTIVES: To describe the profile of, indication for, and complications of shunt surgery in children with portal hypertension. METHODS: Twelve children underwent shunt surgery between 2005 and 2017. Patient records were reviewed. RESULTS: Fourteen procedures were performed on 12 patients during the study period. The median age at surgery was 6.5 (range 1 - 18) years. Six patients were male. Gastrointestinal bleeding that was not amenable to endoscopic control was the most common indication for surgery. Portal vein thrombosis was the most common cause of portal hypertension in our series (n=11). Two-thirds (8/12) of all patients had an identifiable underlying risk factor for portal vein thrombosis. One-third of all patients (4/12) underwent a meso-portal bypass procedure (Rex shunt), while 58% (7/12) were managed with a distal splenorenal shunt. All patients received postoperative thromboprophylaxis. We experienced a single mortality, 1 patient experienced shunt thrombosis that required revision shunt surgery, and 2 patients experienced anastomotic strictures, with one being managed with revision surgery and the other currently awaiting radiological venoplasty. CONCLUSIONS: Surgery is a safe and important tool in the management of children with non-cirrhotic portal hypertension and those with sufficient hepatic reserve who fail to respond to more conservative methods for the treatment of side effects of portal hypertension.

Pyomyositis of the pectineus muscle in an adolescent male.

The 'irritable hip' continues to pose a challenge for clinicians. Even with predictive clinical algorithms, decision making can be difficult. Emergency treatment is required if septic arthritis is suspected. Other differential diagnoses such as transient synovitis, pyomyositis of the pelvic girdle muscles and osteomyelitis must be considered in order to help guide appropriate investigations and allow early treatment. We report the case of a 13-year-old boy presenting to our institution with an acutely painful left hip but still able to weight bear. Despite a fever and raised inflammatory markers, the clinical examination did not correspond to that of an infected hip joint. Urgent magnetic resonance imaging (MRI) confirmed pyomyositis of the pectineus muscle. To our knowledge, this is the first reported case in the literature. The child was treated with seven days of intravenous antibiotics. There was a good clinical response as well as normalisation of the C-reactive protein level and white cell count. The patient was discharged home with a further week of oral antibiotics. Follow-up MRI at two weeks demonstrated a dramatic reduction in the inflammation of the pectineus. At the clinic follow-up appointment, the child was asymptomatic and back to normal function. Pyomyositis is typically found in tropical areas but its rates in temperate climates have been rising. It usually affects large groups of muscles such as the quadriceps and gluteal muscles. MRI is the gold standard investigation. If diagnosed early, the condition can be treated successfully with intravenous antibiotics alone. Given the widespread availability of MRI, we recommend its increased use to distinguish between pyomyositis and other paediatric hip pathologies.