Fungal diversity in the gut microbiome of young South African children.

BACKGROUND: The fungal microbiome, or mycobiome, is a poorly described component of the gut ecosystem and little is known about its structure and development in children. In South Africa, there have been no culture-independent evaluations of the child gut mycobiota. This study aimed to characterise the gut mycobiota and explore the relationships between fungi and bacteria in the gut microbiome of children from Cape Town communities. METHODS: Stool samples were collected from children enrolled in the TB-CHAMP clinical trial. Internal transcribed spacer 1 (ITS1) gene sequencing was performed on a total of 115 stool samples using the Illumina MiSeq platform. Differences in fungal diversity and composition in relation to demographic, clinical, and environmental factors were investigated, and correlations between fungi and previously described bacterial populations in the same samples were described. RESULTS: Taxa from the genera Candida and Saccharomyces were detected in all participants. Differential abundance analysis showed that Candida spp. were significantly more abundant in children younger than 2 years compared to older children. The gut mycobiota was less diverse than the bacterial microbiota of the same participants, consistent with the findings of other human microbiome studies. The variation in richness and evenness of fungi was substantial, even between individuals of the same age. There was significant association between vitamin A supplementation and higher fungal alpha diversity (p = 0.047), and girls were shown to have lower fungal alpha diversity (p = 0.003). Co-occurrence between several bacterial taxa and Candida albicans was observed. CONCLUSIONS: The dominant fungal taxa in our study population were similar to those reported in other paediatric studies; however, it remains difficult to identify the true core gut mycobiota due to the challenges set by the low abundance of gut fungi and the lack of true gut colonising species. The connection between the microbiota, vitamin A supplementation, and growth and immunity warrants exploration, especially in populations at risk for micronutrient deficiencies. While we were able to provide insight into the gut mycobiota of young South African children, further functional studies are necessary to explain the role of the mycobiota and the correlations between bacteria and fungi in human health.

Antibiotic resistance genes in the gut microbiota of mothers and linked neonates with or without sepsis from low- and middle-income countries.

Early development of the microbiome has been shown to affect general health and physical development of the infant and, although some studies have been undertaken in high-income countries, there are few studies from low- and middle-income countries. As part of the BARNARDS study, we examined the rectal microbiota of 2,931 neonates (term used up to 60 d) with clinical signs of sepsis and of 15,217 mothers screening for blaCTX-M-15, blaNDM, blaKPC and blaOXA-48-like genes, which were detected in 56.1%, 18.5%, 0% and 4.1% of neonates' rectal swabs and 47.1%, 4.6%, 0% and 1.6% of mothers' rectal swabs, respectively. Carbapenemase-positive bacteria were identified by MALDI-TOF MS and showed a high diversity of bacterial species (57 distinct species/genera) which exhibited resistance to most of the antibiotics tested. Escherichia coli, Klebsiella pneumoniae and Enterobacter cloacae/E. cloacae complex, the most commonly found isolates, were subjected to whole-genome sequencing analysis and revealed close relationships between isolates from different samples, suggesting transmission of bacteria between neonates, and between neonates and mothers. Associations between the carriage of antimicrobial resistance genes (ARGs) and healthcare/environmental factors were identified, and the presence of ARGs was a predictor of neonatal sepsis and adverse birth outcomes.

NeoCLEAN: a multimodal strategy to enhance environmental cleaning in a resource-limited neonatal unit.

BACKGROUND: Contamination of the hospital environment contributes to neonatal bacterial colonization and infection. Cleaning of hospital surfaces and equipment is seldom audited in resource-limited settings. METHODS: A quasi-experimental study was conducted to assess the impact of a multimodal cleaning intervention for surfaces and equipment in a 30-bed neonatal ward. The intervention included cleaning audits with feedback, cleaning checklists, in-room cleaning wipes and training of staff and mothers in cleaning methods. Cleaning adequacy was evaluated for 100 items (58 surfaces, 42 equipment) using quantitative bacterial surface cultures, adenosine triphosphate bioluminescence assays and fluorescent ultraviolet markers, performed at baseline (P1, October 2019), early intervention (P2, November 2019) and late intervention (P3, February 2020). RESULTS: Environmental swabs (55/300; 18.3%) yielded growth of 78 potential neonatal pathogens with Enterococci, S. marcescens, K. pneumoniae, S. aureus and A. baumannii predominating. Highest aerobic colony counts were noted from moist surfaces such as sinks, milk kitchen surfaces, humidifiers and suction tubing. The proportion of surfaces and equipment exhibiting no bacterial growth increased between phases (P1 = 49%, P2 = 66%, P3 = 69%; p = 0.007). The proportion of surfaces and equipment meeting the ATP "cleanliness" threshold (< 200 relative light units) increased over time (P1 = 40%, P2 = 54%, P3 = 65%; p = 0.002), as did the UV marker removal rate (P1 = 23%, P2 = 71%, P3 = 74%; p < 0.001). CONCLUSION: Routine environmental cleaning of this neonatal ward was sub-optimal at baseline but improved significantly following a multimodal cleaning intervention. Involving mothers and nursing staff was key to achieving improved environmental and equipment cleaning in this resource-limited neonatal unit.

Carbapenem-resistant Enterobacteriaceae in patients with bacteraemia at tertiary hospitals in South Africa, 2015 to 2018.

Enhanced surveillance for CREs was established at national sentinel sites in South Africa. We aimed to apply an epidemiological and microbiological approach to characterise CREs and to assess trends in antimicrobial resistance from patients admitted to tertiary academic hospitals. A retrospective analysis was conducted on patients of all ages with CRE bacteraemia admitted at any one of 12 tertiary academic hospitals in four provinces (Gauteng, KwaZulu-Natal, Western Cape and Free State) in South Africa. The study period was from July 2015 to December 2018. A case of CRE bacteraemia was defined as a patient admitted to one of the selected tertiary hospitals where any of the Enterobacteriaceae was isolated from a blood culture, and was resistant to the carbapenems (ertapenem, meropenem, imipenem and/or doripenem) or had a positive result for the Modified Hodge Test (MHT) according to the Clinical and Laboratory Standards Institute (CLSI) guidelines. A positive blood culture result obtained after 21 days of the last blood culture result was regarded as a new case. To distinguish hospital-acquired (HA) from the community-acquired (CA) bacteraemia, the following definitions were applied: the HA CRE bacteraemia was defined as a patient with CRE isolated from blood culture ≥ 72 h of hospital admission or with any prior healthcare contact, within 1 year prior to the current episode or referral from a healthcare facility where the patient was admitted before the current hospital. A case of the CA CRE bacteraemia was defined as a patient with CRE isolated from blood culture < 72 h of hospital admission and with no prior healthcare contact. The majority of carbapenem-resistant Enterobacteriaceae (CRE) (70%) were hospital-acquired (HA) with Klebsiella pneumoniae being the predominant species (78%). In-hospital mortality rate was 38%. The commonest carbapenemase genes were bla-OXA-48 (52%) and bla-NDM (34%). The high mortality rate related to bacteraemia with CRE and the fact that most were hospital-acquired infections highlights the need to control the spread of these drug-resistant bacteria. Replacement with OXA-48 is the striking finding from this surveillance analysis. Infection control and antibiotic stewardship play important roles in decreasing the spread of resistance.

Paediatric antimicrobial use at a South African hospital.

BACKGROUND: Data on antimicrobial use among hospitalized children in Africa are very limited due to the absence of electronic prescription tracking. METHODS: This study evaluated antimicrobial consumption rates, the antimicrobial spectrum used, and the indications for therapy on a paediatric ward and in the paediatric intensive care unit (PICU) at Tygerberg Hospital, Cape Town, South Africa. Antimicrobial prescription and patient demographic data were collected prospectively from May 10, 2015 to November 11, 2015. For the same period, data on antimicrobials dispensed and costs were extracted from the pharmacy electronic medicine management system. The volume of antimicrobials dispensed (dispensing data) was compared with observed antimicrobial use (prescription data). RESULTS: Of the 703 patients admitted, 415/451 (92%) paediatric ward admissions and 233/252 (92%) PICU admissions received ≥1 antimicrobials. On the ward, 89% of prescriptions were for community-acquired infections; 29% of PICU antimicrobials were prescribed for healthcare-associated infections. Ampicillin and third-generation cephalosporins were the most commonly prescribed agents. Antimicrobial costs were 67541 South African Rand (ZAR) (5680 United States Dollars (USD)) on the ward and 210484 ZAR (17702 USD) in the PICU. Ertapenem and meropenem were the single largest contributors to antimicrobial costs on the ward (43%) and PICU (30%), respectively. The volume of antimicrobials dispensed by the pharmacy (dispensing data) differed considerably from observed antimicrobial use (prescription data). CONCLUSIONS: High rates of antimicrobial consumption were documented. Community-acquired infections were the main indication for prescription. Although pharmacy dispensing data did not closely approximate observed use, this represents a promising method for antimicrobial usage tracking in the future.

Neonatal and paediatric bloodstream infections: Pathogens, antimicrobial resistance patterns and prescribing practice at Khayelitsha District Hospital, Cape Town, South Africa.

BACKGROUND: The epidemiology of neonatal and paediatric community-acquired and healthcare-associated bloodstream infections (BSI) at South African (SA) district hospitals is under-researched. OBJECTIVE: Retrospective review of neonatal and paediatric BSI (0 - 13 years) at Khayelitsha District Hospital, Cape Town, SA, over 3 years (1 March 2012 - 28 February 2015). METHODS: We used laboratory, hospital, patient and prescription data to determine BSI rates, blood culture yield and contamination rates, pathogen profile, antimicrobial resistance, patient demographics, BSI outcome and antibiotic prescribing practice. RESULTS: From 7 427 blood cultures submitted, the pathogen yield was low (2.1%, 156/7 427) while blood culture contamination rates were high (10.5%, 782/7 427). Paediatric and neonatal BSI rates were 4.5 and 1.4/1 000 patient days, respectively. Gram-positive BSI predominated (59.3%); Staphylococcus aureus (26.8%) and Escherichia coli (21.6%) were common pathogens. The median patient age was 3 months, with a predominance of males (57.7%) and a 12.8% prevalence of HIV infection. Crude BSI-associated mortality was 7.1% (11/156), the death rate being higher in neonates than in infants and children (6/40 (15.0%) v. 5/116 (4.3%), respectively; p=0.03) and in patients with Gram-negative compared with Gram-positive bacteraemia (6/66 (9.1%) v. 5/89 (5.6%), respectively; p=0.5). Most BSI episodes were community-acquired (138/156; 88.5%), with high levels of extended-spectrum ß-lactamase (ESBL) carriage among Klebsiella pneumoniae and E. coli isolates (5/5 (100%) and 8/33 (24.2%), respectively). Antimicrobial management of BSI was inappropriate in 30.6% of cases (45/147), including incorrect empirical antibiotic (46.7%), dual antibiotic cover (33.3%) and inappropriately broad-spectrum antibiotic use (17.8%). CONCLUSIONS: Antimicrobial-resistant pathogens (notably ESBL-producing Enterobacteriaceae) were common in community-acquired BSI. Paediatric clinicians at district hospitals require ongoing training in antibiotic stewardship and blood culture sampling.

A small proportion of community-associated methicillin-resistant Staphylococcus aureus bacteraemia, compared to healthcare-associated cases, in two South African provinces.

We compared the proportion of cases of community-associated and healthcare-associated methicillin-resistant Staphylococcus aureus (CA-MRSA and HA-MRSA, respectively) bacteraemia among patients at five hospitals in the Gauteng and Western Cape provinces in South Africa and described the molecular characteristics and antimicrobial susceptibility trends. This was a cross-sectional study using data collected by enhanced surveillance for S. aureus bacteraemia. A total of 2511 cases of S. aureus bacteraemia were identified from January 2013 to January 2016. Among 1914 cases of S. aureus, 557 (29.1%) cases were identified as MRSA infection. Forty-four cases (44/1914 [2.3%] of all S. aureus cases) were considered CA-MRSA infection and 513/1914 (26.8% of all cases) had HA-MRSA infection; the majority were neonates. CA-MRSA constituted 7.9% (44/557) of all cases of MRSA infection. Staphylococcus aureus isolates demonstrated significantly reduced susceptibility to the following classes of antimicrobial agents: macrolides, tetracyclines, aminoglycosides and cotrimoxazole, in 2015 compared to 2013 (p < 0.05). Of the 557 MRSA isolates, 484 (87%) were typed for SCCmec elements and spa types: the most common SCCmec type was type III (n = 236, 48.76%), followed by type IV (n = 144, 29.76%). The most common spa types were t037 (n = 229, 47.31%) and t1257 (n = 90, 18.60%). Of 28 isolates selected for multilocus sequence typing (MLST), the most common sequence types (STs) were ST239 and ST612 of clonal complex 8 (CC8) (n = 8 each) and a novel ST (ST4121) was obtained for one isolate. This study demonstrates that S. aureus bacteraemia is common in South African academic centres and characterised by HA-MRSA SCCmec types III and IV. A small proportion of CA-MRSA cases were caused by a few different sequence types.

A framework for preventing healthcare-associated infection in neonates and children in South Africa.

Healthcare-associated infection (HAI) is a frequent and serious complication affecting 4 - 8% of hospitalised children and neonates in high-income countries. The burden of HAI in South African (SA) paediatric and neonatal wards is substantial but underappreciated, owing to a lack of HAI surveillance and reporting. Maternal and child health and infection prevention are priority areas for healthcare quality improvement in the National Core Standards programme. Despite increasing recognition in SA, infection prevention efforts targeting hospitalised children and neonates are hampered by health system, institutional and individual patient factors. To ensure safe healthcare delivery to children, a co-ordinated HAI prevention strategy should promote development of infection prevention norms and policies, education, patient safety advocacy, healthcare infrastructure, surveillance and research. We present a framework for SA to develop and expand HAI prevention in hospitalised neonates and children.

Burden, spectrum, and impact of healthcare-associated infection at a South African children's hospital.

BACKGROUND: In most African countries the prevalence and effects of paediatric healthcare-associated infection (HCAI) and human immunodeficiency virus (HIV) infection are unknown. AIM: To investigate the burden, spectrum, risk factors, and impact of paediatric HCAI by prospective clinical surveillance at a South African referral hospital. METHODS: Continuous prospective clinical and laboratory HCAI surveillance using Centers for Disease Control and Prevention (CDC)/National Healthcare Safety Network (NHSN) definitions was conducted at Tygerberg Children's Hospital, South Africa, from May 1st to October 31st in 2014 and 2015. Risk factors for HCAI and associated mortality were analysed with multivariate logistic regression; excess length of stay was estimated using a confounder and time-matching approach. FINDINGS: HCAI incidence density was 31.1 per 1000 patient-days (95% CI: 28.2-34.2); hospital-acquired pneumonia (185/417; 44%), urinary tract infection (UTI) (45/417; 11%), bloodstream infection (BSI) (41/417; 10%), and surgical site infection (21/417; 5%) predominated. Device-associated HCAI incidence in the paediatric intensive care unit (PICU) was high: 15.9, 12.9 and 16 per 1000 device-days for ventilator-associated pneumonia, central line-associated BSI and catheter-associated UTI, respectively. HCAI was significantly associated with PICU stay (odds ratio: 2.0), malnutrition (1.6), HIV infection (1.7), HIV exposure (1.6), McCabe score 'fatal' (2.0), comorbidities (1.6), indwelling devices (1.9), blood transfusion (2.5), and transfer in (1.4). Two-thirds of paediatric deaths were HCAI-associated, occurring at a median of four days from HCAI onset with significantly higher crude mortality for HCAI-affected vs HCAI-unaffected hospitalizations [24/325 (7.4%) vs 12/1022 (1.2%); P<0.001]. HCAI resulted in US$371,887 direct costs with an additional 2275 hospitalization days, 2365 antimicrobial days, and 3575 laboratory investigations. CONCLUSION: HCAI was frequent with significant morbidity, mortality, and healthcare costs. Establishment of HCAI surveillance and prevention programmes for African children is a public health priority.

Surveillance of healthcare-associated infection in hospitalised South African children: Which method performs best?

BACKGROUND: In 2012, the South African (SA) National Department of Health mandated surveillance of healthcare-associated infection (HAI), but made no recommendations of appropriate surveillance methods. METHODS: Prospective clinical HAI surveillance (the reference method) was conducted at Tygerberg Children's Hospital, Cape Town, from 1 May to 31 October 2015. Performance of three surveillance methods (point prevalence surveys (PPSs), laboratory surveillance and tracking of antimicrobial prescriptions) was compared with the reference method using surveillance evaluation guidelines. Factors associated with failure to detect HAI were identified by logistic regression analysis. RESULTS: The reference method detected 417 HAIs among 1 347 paediatric hospitalisations (HAI incidence of 31/1000 patient days; 95% confidence interval (CI) 28.2 - 34.2). Surveillance methods had variable sensitivity (S) and positive predictive value (PPV): PPS S = 24.9% (95% CI 21 - 29.3), PPV = 100%; laboratory surveillance S = 48.4% (95% CI 43.7 - 53.2), PPV = 55.2% (95% CI 50.1 - 60.2); and antimicrobial prescriptions S = 66.4% (95% CI 61.8 - 70.8%), PPV = 88.5% (95% CI 84.5 - 91.6). Combined laboratory-antimicrobial surveillance achieved superior HAI detection (S = 84.7% (95% CI 80.9 - 87.8%), PPV = 97% (95% CI 94.6 - 98.4%)). Factors associated with failure to detect HAI included patient transfer (odds ratio (OR) 2.0), single HAI event (OR 2.8), age category 1 - 5 years (OR 2.1) and hospitalisation in a general ward (OR 2.3). CONCLUSIONS: Repeated PPSs, laboratory surveillance and/or antimicrobial prescription tracking are feasible HAI surveillance methods for low-resource settings. Combined laboratory-antimicrobial surveillance achieved the best sensitivity and PPV. SA paediatric healthcare facilities should individualise HAI surveillance, selecting a method suited to available resources and practice context.

Clinical implications of molecular drug resistance testing for Mycobacterium tuberculosis: a TBNET/RESIST-TB consensus statement.

The emergence of drug-resistant strains of Mycobacterium tuberculosis is a challenge to global tuberculosis (TB) control. Although culture-based methods have been regarded as the gold standard for drug susceptibility testing (DST), molecular methods provide rapid information on mutations in the M. tuberculosis genome associated with resistance to anti-tuberculosis drugs. We ascertained consensus on the use of the results of molecular DST for clinical treatment decisions in TB patients. This document has been developed by TBNET and RESIST-TB groups to reach a consensus about reporting standards in the clinical use of molecular DST results. Review of the available literature and the search for evidence included hand-searching journals and searching electronic databases. The panel identified single nucleotide mutations in genomic regions of M. tuberculosis coding for katG, inhA, rpoB, embB, rrs, rpsL and gyrA that are likely related to drug resistance in vivo. Identification of any of these mutations in clinical isolates of M. tuberculosis has implications for the management of TB patients, pending the results of in vitro DST. However, false-positive and false-negative results in detecting resistance-associated mutations in drugs for which there is poor or unproven correlation between phenotypic and clinical drug resistance complicate the interpretation. Reports of molecular DST results should therefore include specific information on the mutations identified and provide guidance for clinicians on interpretation and on the choice of the appropriate initial drug regimen.

Role of infection control in combating antibiotic resistance.

Infection control has been identified as one of the key interventions in controlling the threat of antibiotic resistance. Reducing thetransmission of multidrug-resistant organisms (MDROs) reduces the need for broad-spectrum antibiotics in particular, while interventionsthat decrease the risk of infection have an impact on the use of any antibiotic. Hand hygiene remains the cornerstone of decreasing thetransmission of MDROs. Alcohol-based hand rubs are a cheap, effective and convenient means of performing hand hygiene. Patientscolonised or infected with MDROs should be placed on contact precautions, although implementation remains challenging in resourcelimitedenvironments. Screening for certain MDROs may play a role in curbing transmission of these organisms. If implemented, screeningmust be part of a comprehensive infection control strategy. In resource-limited settings, the costs and potential benefits of screeningprogrammes need to be carefully weighed up. Care bundles have been shown to reduce the incidence of common healthcare-associatedinfections, including catheter-associated urinary tract infection, ventilator-associated pneumonia, central line-associated bloodstreaminfection and surgical site infection. These bundles are relatively inexpensive, and can play an important role in reducing antibiotic use andimproving clinical outcomes.

Two-stage activity-safety study of daily rifapentine during intensive phase treatment of pulmonary tuberculosis.

BACKGROUND: Rifapentine (RPT) has potent activity against Mycobacterium tuberculosis; however, the optimal dose for anti-tuberculosis treatment is unknown. OBJECTIVE: To determine the antimicrobial activity, safety and tolerability of RPT 450 mg or 600 mg administered daily during the first 8 weeks of treatment for pulmonary tuberculosis (TB). DESIGN: In a two-stage, randomised open-label study, adults with sputum smear-positive TB were randomised to receive RPT 450 mg, RPT 600 mg or rifampicin (RMP) 600 mg daily for 8 weeks with isoniazid, pyrazinamide and ethambutol. The primary endpoint was sputum culture status on Löwenstein-Jensen (LJ) medium at completion of 8 weeks of treatment. RESULTS: A total of 153 participants were enrolled. Both RPT regimens met pre-specified criteria to advance to stage 2. At completion of 8 weeks of treatment, LJ culture conversion occurred in 85% (35/41), 96% (43/45) and 94% (34/36) of participants in the RPT 450 mg, RPT 600 mg and RMP groups, respectively. The proportions of participants discontinuing treatment were similar (respectively 1/54 [2.0%], 1/51 [2.0%] and 4/48 [8.3%] in the RPT 450 mg, RPT 600 mg and RMP groups), as were ⩾grade 3 adverse events (0/54 [0%], 1/51 [2.0%] and 4/48 [8.3%]). CONCLUSIONS: There was a trend towards greater efficacy with RPT 600 mg than with RPT 450 mg. Daily RPT was safe and well-tolerated.

A controlled trial of sputum induction and routine collection methods for TB diagnosis in a South African community.

The diagnostic yield of pulmonary tuberculosis (TB) by sputum induction (SI) at the first point of contact with health services, conducted in all patients with suspected TB regardless of the ability to expectorate spontaneously, has not been evaluated. We compared the diagnostic yield of SI to routine sputum collection in a South African community setting. Ambulatory patients with suspected TB provided a 'spot' expectorated sputum sample, an SI sample by hypertonic (5 %) saline nebulization, and early morning expectorated sputum sample. The diagnostic yield of sputum smear microscopy and liquid culture (denominator all subjects with any positive Mycobacterium tuberculosis culture), and time-to-positivity of culture were compared between SI and expectorated samples. A total of 555 subjects completed the SI procedure, of whom 132 (24 %) were human immunodeficiency virus (HIV)-infected. One hundred and twenty-nine samples (129, 23 %) were M. tuberculosis culture-positive. The time-to-positivity of Mycobacteria Growth Indicator Tube (MGIT) culture was shorter for SI (median difference 2 days, p = 0.63) and for early morning expectorated sputum (median difference 2 days, p = 0.02) compared to spot expectorated sputum. However, there was no difference in the culture-positive diagnostic yield between SI and spot expectorated sputum [difference +0.7 %; confidence interval (CI) -7.0 to +8.5 %, p = 0.82] or SI and early morning expectorated sputum (difference +4.7 %; CI -3.2 to +12.5 %, p = 0.20) for all subjects or for HIV-infected subjects. SI reduces the time to positive M. tuberculosis culture, but does not increase the rate of positive culture compared to routine expectorated sputum collection. SI cannot be recommended as the routine collection method at first contact among ambulatory patients with suspected TB in high-burden communities.

Chronic otorrhoea: spectrum of microorganisms and antibiotic sensitivity in a South African cohort.

BACKGROUND: Chronic otorrhoea is difficult to treat, with treatment in South Africa (SA) being protocol driven and generally initiated at the primary healthcare level. There is a lack of local studies that focus on the bacteriology and antimicrobial sensitivities of chronic otorrhoea, which underpins the management advice offered. AIMS: To determine the microbiological profile and antimicrobial susceptibility of patients with chronic otorrhoea and the validity of the Department of Health's (DoH) current guideline. METHODS: We conducted a prospective study at Groote Schuur Hospital from 2005 to 2009. We included patients with chronic otorrhoea classified as either otitis media or otitis externa, according to our definitions. Pus swabs were taken, from which microorganisms were cultured and tested for antimicrobial susceptibility. RESULTS: Of 79 patients with otorrhoea, 50 had otitis media, 21 had otitis externa and the condition was not determined in 8 patients. The most common organism isolated with otitis media was Proteus mirabilis (18/50; 36%) and with otitis externa, Pseudomonas aeruginosa (7/21; 33%). Otorrhoea had a different microbial spectrum compared with international reports, with methicillin-resistant Staphylococcus aureus infection in a single patient. The organisms isolated were susceptible mainly to fluoroquinolones (96%) and aminoglycosides (81%). CONCLUSION: Amoxicillin is a poor choice of antibiotic due to its low sensitivity, which calls into question the current DoH guideline for otorrhoea. Antimicrobial treatment protocols should be based on local data and be revisited from time to time. This study suggests that, should first-line treatment fail, an antibiotic with Gram-negative cover, e.g. a topical fluoroquinolone, should be considered.

Twin birth: an additional risk factor for poorer quality maternal interactions with very preterm infants?

BACKGROUND: Twin birth can be considered an additional risk factor for poor interactions between mothers and their very preterm (VP; <32 weeks' gestation) infants. AIMS: To explore if mothers of (VP) twins experience higher levels of stress than mothers of singletons and if mother-twin infant dyads experience poorer quality interactions. METHOD: Mothers of VP twin infants (N=17) were closely matched to mothers of VP singleton infants (N=17). Mother-infant interaction was assessed before discharge from hospital and during a home visit at three months corrected age using the Nursing Child Assessment Teaching Scale (NCATS). Mothers' responsiveness to their infants was assessed using the Responsivity subscale of the Home Observation for Measurement of the Environment (HOME) and mothers completed the Parenting Stress Index short form (PSI-SF). RESULTS: Mothers of twins had significantly lower HOME responsiveness scores (median 9 vs. 10) at three months corrected age and were more likely to have total PSI-SF scores in the clinical range (>90th percentile) compared to mothers of singletons (Fishers exact probability=0.05). Twin infants had lower mean Total Child Domain NCATS scores than singletons both at discharge (9.07 vs. 11.33) and at three months corrected age (13.18 vs. 15.71) indicating they were less responsive communicators. CONCLUSIONS: VP twins present a greater challenge than singletons as their mothers experience high levels of parenting stress. Although mothers appear to compensate for twin infants' poorer clarity of cues in a structured, one to one task, mothers of twins were less responsive than mothers of singletons in an unstructured setting.

The Clostridium difficile problem: a South African tertiary institution's prospective perspective.

BACKGROUND AND OBJECTIVES: The aim of this study is to report the incidence of Clostridium difficile-associated disease (CDAD) in a tertiary-care hospital in South Africa and to identify risk factors, assess patient outcomes and determine the impact of the hypervirulent strain of the organism referred to as North American pulsed-field type 1 (NAP1). METHODS: Adults who presented with diarrhoea over a period of 15 months were prospectively evaluated for CDAD using stool toxin enzyme immunoassay (EIA). Positive specimens were evaluated by PCR. Patient demographics, laboratory parameters and outcomes were analysed. RESULTS: CDAD was diagnosed in 59 (9.2%) of 643 patients (median age 39 years, IQR 30 - 55). Thirty-four (58%) were female. Recent antibiotic exposure was reported in 39 (66%), 27 (46%) had been hospitalised within 3 months, and 14 (24%) had concomitant inflammatory bowel disease (IBD). Nineteen (32%) had community-acquired CDAD (CA-CDAD). The annual incidence of hospital-acquired CDAD (HA-CDAD) was 8.7 cases/10 000 hospitalisations. Two cases of the hypervirulent strain NAP1 were identified. Seven (12%) patients underwent colectomy (OR 6.83; 95% CI 2.41 - 19.3). On logistic regression, only antibiotic exposure independently predicted for CDAD (OR 2.9; 95% CI 1.6 - 5.1). Three (16%) cases of CA-CDAD reported antibiotic exposure (v. 90% of HA-CDAD, p<0.0001). Twelve (86%) patients had concomitant IBD (p<0.0001 v. HA-CDAD). CA-CDAD was significantly associated with antibiotic exposure (OR 0.04, 95% CI 0.01 - 0.24) and IBD (OR 9.6, 95% CI 1.15 - 79.8). CONCLUSION: The incidence of HA-CDAD in the South African setting is far lower than that reported in the West. While antibiotic use was a major risk factor for HA-CDAD, CA-CDAD was not associated with antibiotic therapy. Concurrent IBD was a predictor of CA-CDAD.

The effect of physiological concentrations of bile acids on in vitro growth of Mycobacterium tuberculosis.

BACKGROUND: Intestinal tuberculosis occurs mainly in the terminal ileum and caecum, where the concentration of bile acids is lowest, and rarely in the upper digestive tract. OBJECTIVES: We examined the effect of physiological concentrations of bile acids on the in vitro growth of Mycobacterium tuberculosis (MTB). METHODS: The 4 major bile acids, lithocolic acid, cholic acid, deoxycholic acid and chenodeoxycholic acid, were added to individual Lowenstein-Jensen (LJ) culture media at physiological concentrations. A combined LJ medium was also prepared using all 4 bile acids. These were double-diluted 4 times by the addition of LJ media. Each culture medium was inoculated with the H37Rv strain of MTB and incubated at 37°C for 8 weeks. MTB growth was measured at 2 and 8 weeks in a semiquantitative fashion using cut-offs of >5, >10, >20, >100 colony-forming units. RESULTS: All lithocolic acid cultures showed uninhibited TB growth at 2 and 8 weeks. Chenodeoxycholic acid, deoxycholic acid and cholic acid alone, and in combination, showed concentration-dependent inhibition of MTB growth at 2 and 8 weeks. Four cultures were lost to contamination. CONCLUSIONS: Certain bile acids alone and in combination, at physiological concentrations, inhibit the growth of MTB in vitro. This might explain why intestinal TB occurs in the ileocaecum in the majority of cases and why gallbladder TB is very rare.

Complement component C5 and C6 mutation screening indicated in meningococcal disease in South Africa.

BACKGROUND: Invasive meningococcal disease (MD), caused by Neisseria meningitidis infection, is endemic in South Africa, with a seasonal peak in winter and spring. There were 2 432 laboratory-confirmed cases between 2006 and 2010. Human deficiency of the fifth complement component (C5D) or complete absence of the sixth component (C6Q0) leads to increased risk of MD, which is often recurrent. All attacks are serious and can lead to death or severe long-term consequences. OBJECTIVE: To determine the frequency of specific disease-associated C5 and C6 gene mutations in patients presenting with MD in the Western Cape. RESULTS: In 109 patients with confirmed invasive MD investigated for local mutations known to cause C5D and C6Q0, 3 were C5D and 11 were C6Q0. In 46 black patients tested, 3 were C5D and 7 were C6Q0. In 63 coloured patients, none were C5D and 4 were C6Q0. All deficient patients were followed up and offered prophylaxis. CONCLUSION: C5D and C6Q0 are not rare genetic diseases in South Africa and affected patients are susceptible to repeated MD; 12.8% of MD patients tested were C5D or C6Q0. Blacks were at greatest risk with 21.7% being either C5D or C6Q0. We strongly recommend diagnostic testing for complement C5 and C6 deficiency in the routine work-up of all MD cases in South Africa. Prophylactic treatment should be started in susceptible individuals.