Postoperative infections: Aetiology, incidence and risk factors among neurosurgical patients in Mthatha, South Africa.

BACKGROUND: Despite progress in hospital care, infections continue to represent one of the major complications among hospitalised patients. OBJECTIVES: To determine the aetiology and incidence of hospital-acquired infections and their associated risk factors following neurosurgical procedures. METHODS: A retrospective study was conducted from October 2013 to September 2014. Data including demographics, hospitalisation period, type of operation and primary diagnosis were collected. Post-surgical infections were confirmed microbiologically. SPSS (Statistical Package for the Social Sciences) version 23 was used for statistical analysis. RESULTS: Among a total of 1 688 patients who underwent neurosurgical operations, the incidence of post-surgical infections was 4.2% per year. Post-surgical infections were significantly associated with craniotomy (p<0.0001), prolonged stay in hospital (≥30 days) (p=0.008), and patient age ≥35 years (p=0.05). Staphylococcus aureus was the most frequently isolated pathogen (19.7%), followed by Klebsiella pneumoniae (12.7%). A total of 42.9% of S. aureus isolates were methicillin-resistant S. aureus (MRSA), but all these isolates were susceptible to vancomycin; 44.4% of K. pneumoniae isolates were extended-spectrum beta-lactamase (ESBL)-positive, but were susceptible to carbapenems, piperacillin-tazobactam and amikacin. CONCLUSIONS: Post-surgical infections remain an important problem in neurosurgery. Increased resistance to causative pathogens is a major concern.

Species distribution and antifungal susceptibility patterns of Candida isolates from a public tertiary teaching hospital in the Eastern Cape Province, South Africa.

Candida species are the leading cause of invasive fungal infections, and over the past decade there has been an increased isolation of drug resistant Candida species. This study aimed to identify the species distribution of Candida isolates and to determine their unique antifungal susceptibility and resistance patterns. During a cross-sectional study, 209 Candida isolates (recovered from 206 clinical samples) were collected and their species distribution was determined using ChromAgar Candida. The Vitek-2 system (Biomerieux, South Africa) was used to determine minimum inhibitory concentrations (MICs) to azoles (fluconazole, voriconazole), echinocandins (caspofungin, micafungin), polyenes (amphotericin B) and flucytosine. Four species of Candida were isolated, of which C. albicans was the most frequent, isolated in 45.4% (95/209) of the isolates, followed by C. glabrata: 31.1% (65/209). The MICs of the different antifungal drugs varied amongst the species of Candida. From the 130 isolates tested for MICs, 90.77% (112/130) were susceptible to all antifungal drugs and 6.9% (9/130) of the isolates were multi-drug resistant. C. dubliniensis (n=2) isolates were susceptible to all the above mentioned antifungal drugs. There was no significant difference in species distribution amongst clinical specimens and between patients' genders (P>0.05). An increase in MIC values for fluconazole and flucytosine towards the resistance range was observed. To our knowledge, this is the first report on surveillance of Candida species distribution and antifungal susceptibility at a public tertiary teaching hospital in Eastern Cape, South Africa.

Bacteriological Profile and Antibiogram of Aerobic Burn Wound Isolates in Mthatha; Eastern Cape; South Africa

Burn wound colonisation and infection is not only associated with delayed wound healing and scar formation; but may also lead to sepsisrelated mortality. A wide variety of microorganisms; like staphylococcus aureus; Pseudomonas aeruginosa; and Enterobacteriaceae-like Klebsiella pneumoniae and Escherichia coli; are involved. Resistance is generally increasing; with reports of multidrug-and pan-resistant isolates. This study was conducted to determine the common aerobic bacterial isolates in our setting and describe their antimicrobial susceptibility. This retrospective; descriptive study was carried out on 243 patients; from whom 312 burn wound specimens were received by the Nelson Mandela Academic Hospital microbiology laboratory of the National Health Laboratory Service; Mthatha. All samples were processed according to standard laboratory protocols; isolates were tabulated according to age and gender of the patients; and their percentage susceptibilities to relevant antibacterials were computed. A total of 229 patient specimens showed growth on culture. The total number of isolates was 629; out of which 269 were Gram-positive cocci and 360 were Gram-negative bacilli. The commonest organism was S. aureus (27.7); followed by K. pneumoniae (13.4); Proteus mirabilis (12.4); Group D streptococcus (9.4); P. aeruginosa (8.9) and E. coli (6.2). A generally high level of resistance was observed in many organisms. Methicillinresistant S. aureus accounted for 57.5of the S. aureus. Resistance among the Gram-negative bacilli was; in general; least to imipenem; amikacin and ciprofloxacin. The common organisms causing burn wound infections in our setting include staphylococci; Klebsiella; Proteus and Pseudomonas and there is a high level of resistance against commonly used antimicrobials. Regular surveillance of burn wound organisms and their antimicrobial resistance patterns will help in determining empirical antibiotic therapy for subsequent related septic events

Correlation between Different PBL Assessment Components and the Final Mark for MB ChB III at a Rural South African University

Problem-based learning (PBL) is now an accepted component of many medical school programmes worldwide. Our university also follows the PBL `SPICES' model for MB ChB III. The assessment modalities used are the modified essay questions (MEQ); objective structured practical examination (OSPE); individualised process assessment (IPA) and tutorial continuous assessment (TUT). This study was done to compare the students' performances in individual assessment components with the final mark to determine the correlation between these parameters. Materials and methods. The study was retrospective; descriptive and analytical; based on the integrated marks of all the MB ChB III students at Walter Sisulu University (WSU) in 2007. Assessment marks were stratified according to blocks and different types of assessment (MEQ; TUT; OSPE; IPA). Regression analysis was used to compute and scrutinise these vis-a-vis their correspondence with the final marks for each block.Results. Three hundred and seventy-nine block assessment marks of 96 students from 4 blocks of MB ChB III were analysed and the correlation between the assessment components and final mark were compared. Regression analysis showed good correlation when analysing the assessment modality versus the final mark for the MEQs (r=0.93; 0.93; 0.94; 0.96); followed by OSPEs (r=0.71; 0.70; 0.76; 0.77) and IPAs (r=0.62; 0.51; 0.68; 0.77). However; correlation was not significant with the TUT. Conclusion. There was good correlation between the students' performance in the majority of assessment modalities and the final mark in the different blocks of the MB ChB III examination. There may be a need to make tutorial assessment methods more objective; partly by additional tutor training

Aeromonas species isolated from cases of acute gastroenteritis.

A total of 67 Aeromonas strains were isolated as the sole bacterial pathogen from 1485 patients with acute gastroenteritis. A. hydrophila (64.2%) was the predominant isolate followed by A. sobria (28.4%) and A.caviae (7.4%). Majority of the isolates were sensitive to gentamicin, nalidixic acid but were resistant to ampicillin. Minimum inhibitory concentration (MIC) of resistant strains of Aeromonas to ampicillin ranged from 80-1280 microg/mL.