Delayed diagnosis of anorectal malformations (ARM): causes and consequences in a resource-constrained environment.

PURPOSE: Delay in diagnosis or referral of patients with an anorectal malformation (ARM) is associated with significant morbidity and mortality. We describe the frequency and consequences of delay in recognition or referral of patients with ARM. Our study aims to determine whether the source healthcare facility affects the timing of diagnosis and to identify modifiable factors that may expedite diagnosis and referral. METHODS: Retrospective study of patients referred to a pediatric surgical service with a newly diagnosed ARM between July 2002 and December 2010. Data retrieved included patient demographics, perinatal history, time of diagnosis, clinical findings, management, and morbidity and mortality. Delay was defined as diagnosis after 24 h of birth or transfer to the tertiary referral centre more than 24 h after diagnosis. RESULTS: 273 patients (186 males, 87 females) were referred during the study period. Delays were seen in 158 (57.9%) patients with morbidity in 58 (36.7%, p < 0.001) and mortality in 9 (5.7%, p = 0.008). Delay was more frequent amongst babies born in community health centres (CHCs) than in hospitals (90.5 vs. 55.1%, p = 0.002). The median age at diagnosis was 3 days (range 2 days to 5 years). CONCLUSION: There is a need for staff education, particularly in CHCs, concerning routine neonatal examination and normal perineal anatomy. Girls, in whom a decompressive fistula is often present, are at particular risk of diagnostic delay. Delay causes increased morbidity and mortality.

The academic progress of female general surgery and orthopaedic surgery trainees in South Africa.

BACKGROUND: Globally, medical institutes have seen an increase in female graduates, however surgical disciplines remain male-dominated. An epidemiological shift towards non-communicable diseases and trauma may result in a shortage of surgical specialists. One strategy to improve the surgical workforce is the recruitment of female graduates. METHODS: A non-validated questionnaire was administered to females registered for the Master of Medicine (MMED) degree in General and Orthopaedic Surgery at the University of KwaZulu-Natal (UKZN) between 2000 and 2015. The study evaluated reasons for choice of surgery as a career, challenges faced on the domestic and work front, as well as factors that assisted with successful completion of training. RESULTS: Seventy-two female trainees in General Surgery and Orthopaedics were identified from the UKZN databases. The contact details for 62 of these trainees were available. The overall response rate was 71.0% (44/62). A total of 95.5% (42/44) of participants selected surgery due to a passion for the field. Major challenges identified were a poor home and work-life balance (72.1%, 31/43) and poor working conditions (62.8%, 27/43). Female trainees perceived that they were viewed as inferior by patients (65.9%, 29/44). Successful trainees had a good home support system (89.3%, 25/28) and mentorship during training (60.7%, 17/28), and 85.7% (24/28) did not regret their career choice. CONCLUSION: The recruitment and retention of females in surgery will contribute to maintaining an adequate surgical workforce. Training programmes need to improve work-life balance without compromising on producing competent surgeons. Improved visibility of female surgeons in leadership roles should be encouraged to promote mentorship and recruitment of trainees.

Antivirals for the treatment of mild and moderate COVID-19 in South Africa.

While the majority of COVID-19 cases in South Africa (SA) are mild, patients with severe COVID-19 requiring hospitalisation present with significant morbidity and mortality and place a substantial burden on healthcare services. Given the low vaccine uptake in SA and other low- and middle-income countries in sub-Saharan Africa, the high prevalence of comorbidities and limited healthcare system capacity, evidence-based interventions that reduce the risk of severe disease and death should be considered for implementation. Several antiviral classes have been newly developed or repurposed to treat COVID-19 early after infection to retard progression to severe disease and reduce the risk of death, particularly in the elderly and/or in patients with comorbidities. COVID-19 antivirals such as remdesivir, nirmatrelvir/ ritonavir and molnupiravir are safe and cost-effective and have received either full approval or emergency use authorisation from regulators. Using a proposed test-and-treat strategy, judicious use of antivirals could be impactful.

Placental histopathology, maternal characteristics and neonatal outcome in cases of preterm birth in a high-risk population in South Africa.

BACKGROUND: Preterm birth remains a global health concern and is one of the most common pregnancy complications associated with perinatal morbidity and mortality. OBJECTIVE: To investigate placental pathology and its associations with obstetric, maternal and neonatal outcomes in the Eastern Cape region of South Africa (SA) in order to help understand its associations with preterm birth in that region. METHODS: In this prospective study, placentas were collected consecutively from patients attending a public tertiary referral hospital in SA, delivering preterm (n=100; 28 - 34 weeks gestational age) and term (n=20; >36 weeks gestational age). Placentas were submitted for histopathology, and comparisons with maternal characteristics and neonatal outcomes in preterm birth were undertaken. RESULTS: Histological analysis revealed pathology in all preterm placentas (100%), with maternal vascular malperfusion (47%) and abruptio placentae (41%) most commonly identified. Acute chorioamnionitis (21%) was associated with term births (p=0.002). Maternal characteristics and neonatal outcomes significantly associated with preterm birth included pre-eclampsia (p=0.006), neonatal respiratory distress syndrome (p=0.004) and neonatal jaundice (p=0.003). Intrauterine demise (p=0.004) and alcohol abuse (p≤0.005) were significantly associated with term delivery. The number of mothers delivering preterm who were HIV-positive was high (41%). CONCLUSION: The pathology identified in all preterm placentas supports the need to update institutional policies for submission of placentas from all preterm births for histopathology, particularly in countries with a high burden of preterm birth.

Neurological manifestations of syphilis-HIV coinfection in South Africa.

OBJECTIVE: Syphilis and HIV coinfection is highly prevalent in South Africa, and both can cause neurological complications. We describe the clinical presentation and outcome of neurosyphilis in patients with and without HIV coinfection diagnosed at a tertiary facility, Groote Schuur Hospital (GSH), in South Africa. METHODS: We retrospectively analyzed folders of adults with positive cerebrospinal fluid (CSF) fluorescent treponemal antibody absorption test in 2018 and 2019, with follow-up data collected until 2022. RESULTS: HIV-coinfection was identified in 35% of the 69 included patients. Patients with HIV-coinfection were more likely to be female (58% vs 25% female, p < 0.01), and present earlier (median age = 31 years vs. 40 years, p < 0.001). Neuropsychiatric manifestations (confusion, dementia, psychosis), and strokes were the commonest clinical presentations in both groups. Those with HIV-coinfection were significantly less likely to be diagnosed with neurosyphilis by the treating clinician (71% vs. 91%, p < 0.05), as were those with a negative CSF Venereal Disease Research Laboratory (74% vs. 94%, p < 0.05). Accurate diagnosis of neurosyphilis was associated with an increased 12-month survival (alive: N = 36 [63%]) relative to those who did not receive an accurate diagnosis (alive: N = 2 [17%], p < 0.05). Those who were optimally treated with antibiotics had significantly higher 12-month survival (alive: N = 33, 63%) compared to those with suboptimal treatment (alive: N = 5, 29%), p < 0.01. CONCLUSION: Neurosyphilis presented similarly in those with and without HIV-coinfection. Accurate identification and optimal antibiotic treatment of neurosyphilis, particularly in CSF VDRL negative patients and those with HIV-coinfection, is necessary to improve patient survival.

Antibiotic susceptibilities and resistance genes of Ureaplasma parvum isolated in South Africa.

OBJECTIVES: There is only limited information on the antimicrobial susceptibilities and resistance genes of Ureaplasma parvum in South Africa. This study was designed to detect and characterize resistance genes in U. parvum. METHODS: Fifteen U. parvum isolates were investigated employing the broth microdilution method (tetracycline, doxycycline, ofloxacin, erythromycin, azithromycin and josamycin). Gene analyses were performed on target regions of: tet(M); gyrA, gyrB, parC and parE; erm(A), erm(B), erm(C) and erm(E); msr(A), msr(B), msr(C) and msr(D); 23S rRNA operons; and L4 and L22 ribosomal proteins. RESULTS: Seven of the U. parvum isolates were fully susceptible to the antibiotics tested. Five strains exhibited resistance to tetracycline (MICs 16-256 mg/L), one strain was resistant to ofloxacin (MIC 128 mg/L) and four strains were resistant to macrolides (MICs 128 mg/L); two strains showed dual resistance to tetracycline and erythromycin. The five tetracycline-resistant strains were found to have mosaic tet(M) genes, with one strain containing different specific regions to those previously described. Mutations in the L22 ribosomal protein were seen in three strains that were resistant to erythromycin (two strains) and erythromycin + azithromycin (one strain). For a further strain that was resistant to erythromycin and azithromycin, possible mechanisms of resistance remained elusive. CONCLUSIONS: This is the first report of quinolone, erythromycin and azithromycin resistance development in U. parvum from South Africa. A point mutation in parC (Pro-57 → Leu) and two novel mutations in parE (Ile-73 → Thr and a methionine insertion at codon 86) were found in an ofloxacin-resistant strain. The study reinforces the adaptability of U. parvum to develop resistance and acquire, modify and maintain transposon-located resistance genes.

Biofilm productivity and concomitant cell autolysis in a membrane bioreactor.

Phanerochaete chrysoporium morphology and manganese peroxidase (MnP) productivity was characterised in a scalable, modularised 1145 cm(3) membrane gradostat reactor in response to switching between an enhanced production medium and a nutrient limited feed (50% C and N reduction). Irrespective of the feed composition used nutrients permeating from the lumen of the ultrafiltration membrane matrix established nutrient gradients across the immobilised biofilm with distinct primary, stationary and decline growth phases observed. Severe nutrient C and N limitation did not change the cyclic nature of enzyme production (MnP(max) = 189.5 U l(-1)) but did reduce the overall bioreactor efficiency from 32 to 22 U l(-1) day(-1). Stress induced secondary metabolism resulted in concomitant cell autolysis causing biomass loss and increased operational flux after 20 days in the 33 day bioreactor operation cycle.

A multicentre cross-sectional descriptive study evaluating the cardiovascular risk profile of preoperatively identified patients with hypertension.

BACKGROUND: The prevalence of hypertension in adults in South Africa (SA) is 35%. Hypertension is the most important modifiable risk factor for cardiovascular (CV) and chronic kidney disease (CKD) in sub-Saharan Africa. However, 49% of people are unaware of their blood pressure status. Screening for hypertension prior to surgery provides a unique opportunity to diagnose and treat affected individuals. Furthermore, assessing overall CV risk identifies patients at highest risk for complications, and improves the utilisation of scarce resources. OBJECTIVES: To evaluate the CV risk profile of hypertensive patients in the adult population of the Western Cape Province presenting for elective non-cardiac, non-obstetric surgery. METHODS: This report documents the CV risk profile of patients recruited to the HASS-2 study (Hypertension and Surgery Study 2), which was undertaken in seven Western Cape hospitals. Patients were screened for hypertension and pharmacological treatment was initiated or adjusted in patients with stages 1 and 2 disease. Stage 3 patients were referred to a physician. In the present substudy, patients with stages 1 and 2 hypertension were assessed for associated CV risk factors, the presence of target organ damage, and documented CV or kidney disease; they received an overall risk stratification according to the 2018 European Society of Cardiology and the European Society of Hypertension Guidelines. RESULTS: Sixty-one patients with stage 1 and 12 with stage 2 hypertension were analysed. Established CV disease was present in 13.7% of the study population, and CKD (eGFR <60 mL/min) in 10.8%. Seventy-one percent of the study group had a raised body mass index, and 55.9% underlying metabolic syndrome. Prediabetes and diabetes were present in 16.1% and 14.5%, respectively. According to the 2018 European guidelines, 34.7% were at moderate, 33.3% at high and 16.7% at very high risk for a CV event in the following 10 years. CONCLUSIONS: The perioperative period is a critical time during which surgeons, nurses and anaesthetists can influence patients' CV risk of adverse events. This involves appropriate screening, education and treatment. In this study population, nearly 9 out of 10 elective surgical patients with stage 1 or 2 hypertension had CV risk factors placing them at moderate to very high risk. The simultaneous assessment of these additional CV risk parameters, in addition to diagnosis and management of hypertension, may further decrease the health and financial burden in resource-limited facilities in SA, and improve CV outcomes.

Prevalence of genital mycoplasmas, ureaplasmas and chlamydia in pregnancy.

The study was designed to determine the prevalence of genital mycoplasmas, ureaplasmas and Chlamydia on women attending their first prenatal visit, in conjunction with pre-term labour or HIV status. For pre-term labour (2003), 199 women were monitored for pre-term delivery (<37 weeks); for colonisation and HIV (2005), 219 women were screened. Microbial detection was performed on DNA extracted from endocervical swabs employing PCR techniques. Colonisation was seen to be highest in the 14-20 year age group from 2003. In women aged > or = 21 years, co-colonisation was 13%, although there was a shift from co-colonisation with Mycoplasma hominis and Ureaplasma urealyticum in 2003, to other dual/triple combinations in 2005. Overall, major trends from both collection periods were that the prevalence of U. urealyticum tended to be higher in women > or = 26 years, while the prevalence of Chlamydia trachomatis and M. hominis lower. No association was evident between colonisation with M. hominis, U. urealyticum, Ureaplasma parvum and labour outcome. HIV status had no effect on the prevalence/co-colonisation of M. hominis, U. urealyticum or C. trachomatis. The importance of genital mycoplasmas, ureaplasmas and C. trachomatis in long-term aetiologies requires further investigations, certainly in relation to syndromic management regimens that fail to reduce colonisation rates.

Impact of HIV on bone and joint surgery.

In 2007, approximately 33 million people were living with human immunodeficiency virus (HIV) infection worldwide. Sub-Saharan Africa has been hardest hit by the HIV pandemic. In this chapter the impact of HIV infection on bone and joint surgery is reviewed. The management of orthopaedic trauma and diseases specific to HIV infection (such as osteonecrosis, bone tumours, and bone and joint infection) in patients with HIV infection are discussed. The importance of universal protection during surgical procedures is emphasized. The guidelines developed by the Centers for Disease Control for HIV-positive health workers and their involvement in the treatment of these are discussed.

The supraodontoid space or "apical cave" at the craniocervical junction: a microdissection study.

The extradural supraodontoid space lies anteriorly at the craniocervical junction (CCJ) between the alar ligaments and foramen magnum. It occupies the space between the tectorial and atlanto-occipital membranes. A variety of benign and traumatic lesions may result in neurological compression here with harmful effects. Decompression by the transoral surgical approach often provides relief from these effects. Knowledge of the detailed microanatomy of this space is fragmentary. The purpose of this study was to identify the boundaries and contents of this space by microdissection. Twenty-three en bloc preserved adult cadaveric specimens of the CCJ were dissected to identify the boundaries and contents of the supraodontoid space. The posterior bony elements of the CCJ were removed to enable microdissection (Zeiss DXE Microscope 4-40x) from the tectorial membrane (TM) forwards. The cave-like space faced posteriorly. It had a roof which extended into a wall (anterior atlanto-occipital membrane), a floor (superior surface of the alar ligament), and a mouth covered by the TM. The apical ligament and a thin lining membranous fatty layer divided the cave into a pair of symmetrical halves. The contents, from dorsal to ventral, lay deep to a thin subtectorial membrane. These were the superior fasciculus of the cruciate ligament, a fat-ensheathed knot of plexiform veins (which communicated with the surrounding CCJ vertebral venous plexuses), an arterial arcade between the veins, a pair of fat pads, and branches of the sinuvertebral nerves of the CCJ (lying on the floor). No synovial membrane was found. Knowledge of the anatomy of the apical cave may be of some assistance in transoral (extra- and transdural) surgical approaches to the anterior CCJ region.

Sacral chordoma : A review of literature.

Chordoma is a rare malignant tumor with predilection for the sacrum. A favorable outcome depends on early diagnosis and surgical excision with tumor free margins. AIM: To review the incidence and prevalence of sacral chordoma and the appropriate surgical management and formulate a criteria for early diagnosis. MATERIALS AND METHODS: Thirty eight articles on the subject of sacral chordoma and extrapolated data of clinical and surgical significance. RESULTS: The commonest presenting feature in patients with sacral chordoma was lower back pain which was worse on sitting and up to a third of these patients had associated urinary tract infections, constipation or symptoms of disc herniation. The hallmark of sacral chordoma is lower back pain with poor response to non-steroidal anti-inflammatory drugs.Disease free eradication in chordoma is rare and not without neurological deficit. The common sacral levels involved ie. S2,3 have to be sacrificed to achieve adequate margins4. Whilst wide excision via posterior surgery shows a decrease in recurrence, the overall survival still remains low.

Validity of automated threshold audiometry in school aged children.

BACKGROUND: Automated hearing tests have the potential to reduce the burden of disease amongst learners by introducing such services within the school context. METHODS: The aim of the study was to conduct a validation study on normal and hearing impaired learners, comparing air and bone conduction automated test results to conventional test results in 50 school aged learners (n = 100 ears) within a noise controlled school environment using a cross sectional comparative study design. The KuduWave 5000 (Emoyo.net) was used in this study. DATA ANALYSIS: The spearman's correlation coefficient was calculated to determine test-retest reliability. The mean and standard deviation (SD) was measured for each frequency. The absolute mean difference (AMD) and SD was calculated for both air and bone conduction testing at each frequency for automated testing. A paired sampled t-test and a one way ANOVA was used to identify any significant differences. Alpha was set as 0.05. RESULTS: There was significant correlation between thresholds obtained for automated test one and test two for normal hearing and hearing impaired group. The spearmans correlation coefficient was high (close to +1) for majority of the results for both groups across the frequency range. Both air and bone conduction testing across the frequency range of 250 Hz-2000 Hz and at 8000 Hz were not statistically signfiicant (p < .005) for both groups, however at 4000 Hz for bone conduction testing in the hearing impaired group, there was a statisticially signficant difference (p = .003). This was attirubted to the variaibilty in bone conduction test results often due to force and placement of the bone vibrator. CONCLUSION: The findings indicate that automated audiometry can yield relaible results that are comparable to conventional test results. Key clinical considerations include extending the response time, regular rest periods, improving instructions and comfort levels.

Affinity chromatography using biocompatible and reusable biotinylated membranes.

A novel, reusable biotinylated affinity chromatography strategy for the bio-specific binding of bioactive avidin tagged enzymes or polypeptides is reported. Using an avidin coupled peroxidase fusion protein as a test system; non-specific protein shielding and matrix regeneration were also shown. The amphiphilic surfactant Pluronic F108 was used as an affinity linker, by non-covalent binding to membrane chromatographic matrices while the terminal hydroxyl groups of Pluronic were covalently coupled to the biological ligand biotin. Planar nonporous membranes of varying surface chemistry were synthesised to test the matrix dependent affinity binding of biotinylated Pluronic and their respective ability to resist non-specific protein adsorption. Membrane regeneration using sodium dodecyl sulphate (SDS) was capable of displacing both adsorbed proteins and Pluronic. SDS micelles (34 mM) were effective in desorbing membrane bound protein while 5mM SDS removed up to 85% of the bound ligand after 20 h incubation at 20 degrees C. In this study, polyvinylidene membranes had the highest ligand binding capacity of 0.22 mg cm(-2) and specific, competitive affinity binding of avidin-peroxidase was shown in the presence of up to 0.2 mg ml(-1) 'contaminant' proteins. The resultant biocompatible affinity chromatographic system was regenerated and reused with no significant change in performance for up to five cycles.

The use of telehealth services to facilitate audiological management for children: A scoping review and content analysis.

Approximately 32 million children globally present with disabling hearing loss. Despite evidence describing the negative consequences of hearing loss, there is still a lack of hearing screening programmes in South Africa. Audiologists have been exploring the use of information and communication technologies (tele-audiology) to provide services to children and it is currently being evaluated to determine its feasibility. Aims We aim to describe tele-audiology services conducted to facilitate audiological management for children in both the rural and urban context and to determine the strengths, challenges and clinical implications of such services. Methods A scoping review was conducted by searching for peer-reviewed publications from five databases. Inclusion criteria and search strategies were outlined. Results Of the 23 studies that met the inclusion criteria, reliability of automated testing was comparable to conventional testing; however, these studies were based primarily on screening programmes. Eight (35%) of the 23 papers were concordance studies evaluating feasibility and validity of tele-audiology systems when compared with conventional testing, while one study (4%) evaluated a tele-audiology service. A further four studies (17%) evaluated the feasibility of introducing telehealth methods to evaluate middle ear pathology. Tele-auditory brainstem response was investigated in three studies (13%) and another five (22%) used smartphone and/or iPad technology to screen hearing. Only two studies (9%) evaluated the feasibility of providing intervention through telehealth methods. All included studies demonstrated improved access to and coverage of rural areas. Services such as video otoscopy and synchronous (online) hearing testing in remote areas were successfully implemented. Challenges included lack of diagnostic studies, inadequate training of staff and the need to standardize protocols and procedures in order to ensure that tele-audiology services are provided in a standardized and valid manner. Conclusion Tele-audiology services are feasible and can be useful in identifying auditory pathology for children in rural and remote areas.

MULTILOCUS SEQUENCE TYPING OF CARBAPENEM RESISTANT PSEUDOMONAS AERUGINOSA ISOLATES FROM PATIENTS PRESENTING AT PORT ELIZABETH HOSPITALS, SOUTH AFRICA.

BACKGROUND: Pseudomonas aeruginosa is an important nosocomial pathogen that exhibits multiple drug resistance with increasing frequency, especially to carbapenems making patient treatment difficult. Carbapenem-resistance may be caused by porin gene mutations, active drug efflux, and carbapenemase production. This study evaluated the incidence of genes responsible for carbapenemase production in carbapenem-resistant Pseudomonas aeruginosa and assessed the genetic relatedness of the isolates by multi locus sequence typing (MLST). MATERIALS AND METHODS: Identification and antimicrobial susceptibility testing of P. aeruginosa isolates (n=234) by the VITEK 2 system detected 81 carbapenem resistant P. aeruginosa isolates. PCR and DNA sequencing were used to screen isolates for three metallo-ß-lactamase encoding genes. MLST included amplification of seven housekeeping genes and sequence type alignment using the online P. aeruginosa MLST database. RESULTS: Only the blaVIM-2 gene was detected in 15 of the 81 carbapenem resistant isolates. MLST indicated six different novel sequence types among the blaVIM-2 positive P. aeruginosa isolates with the majority of the isolates (9/15) containing identical allelic profiles of the sequence type allocated ST1 (provisionally assigned sequence type, awaiting addition of new sequence types to PubMLST database). Five of these ST1 isolates were from patients and an environmental sample in the same hospital ward suggesting an environmental reservoir. Carbapenem resistance in the blaVIM-2 negative isolates may be due to other mechanisms. CONCLUSION: The incidence of genes responsible for carbapenemase production in carbapenem-resistant Pseudomonas aeruginosa and genetic relatedness of these isolates in public healthcare facilities within the Port Elizabeth area is of concern and requires further investigation.

Vestibular-dependent inter-stimulus interval effects on sound evoked potentials of central origin.

Todd et al. (2014ab) have recently demonstrated the presence of vestibular-dependent contributions to auditory evoked potentials (AEPs) when passing through the vestibular threshold as determined by vestibular evoked myogenic potentials (VEMPs), including a particular deflection labeled as an N42/P52 prior to the long-latency AEPs N1 and P2. In this paper we report the results of an experiment to determine the effect of inter-stimulus interval (ISI) and regularity on potentials recorded above and below VEMP threshold. Five healthy, right-handed subjects were recruited and evoked potentials were recorded to binaurally presented sound stimulation, above and below vestibular threshold, at seven stimulus rates with ISIs of 212, 300, 424, 600, 848, 1200 and 1696 ms. The inner five intervals, i.e. 300, 424, 600, 848, 1200 ms, were presented twice in both regular and irregular conditions. ANOVA on the global field power (GFP) were conducted for each of four waves, N42, P52, N1 and P2 with factors of intensity, ISI and regularity. Both N42 and P52 waves showed significant ANOVA effects of intensity but no other main effects or interactions. In contrast both N1 and P2 showed additional effects of ISI, as well as intensity, and evidence of non-linear interactions between ISI and intensity. A source analysis was carried out consistent with prior work suggesting that when above vestibular threshold, in addition to bilateral superior temporal cortex, ocular, cerebellar and cingulate sources are recruited. Further statistical analysis of the source currents indicated that the origin of the interactions with intensity may be the ISI sensitivity of the vestibular-dependent sources. This in turn may reflect a specific vestibular preference for stimulus rates associated with locomotion, i.e. rates close to 2 Hz, or ISIs close to 500 ms, where saccular afferents show increased gain and the corresponding reflexes are most sensitive.

Poor Performance of the Chlamydia Rapid Test Device for the Detection of Asymptomatic Infections in South African Men: A Pilot Study.

Background. To the best of our knowledge, there have been no published reports on the diagnostic performance of the Chlamydia Rapid Test (CRT) Device for male urine samples. We evaluated the performance of the CRT Device when compared with that of the BD ProbeTec ET PCR Assay in a population of asymptomatic men. Methods. The study enrolled 100 men between June and July 2015. From each consenting male, 20-30 mL of urine was collected. Sensitivity and specificity of the rapid test compared to PCR were calculated. All analysis was performed in STATA version 13. Results. All men had valid rapid and PCR test results. The test showed a low sensitivity against PCR (20%) (95% CI 3.7-6.2%); however, an excellent specificity was observed (100%) (one sided 97.5% CI: 96.0-100). Conclusions. This test was not found to be suitable as a screening tool for genital Chlamydia infections in men. Our findings emphasize the need for more sensitive POC tests to be developed since the current approach for the management of STIs in Africa is confounded by poor sensitivity and specificity resulting in many infected individuals not being treated.

Optimisation and characterisation of bioadhesive controlled release tetracycline microspheres.

A Box-Behnken experimental design was employed to statistically optimise the formulation parameters of a tetracycline microsphere preparation for maximum bioadhesivity and controlled drug release. The quantitative effect of the formulation parameters at different levels on bioadhesion and drug release could be predicted using polynomial equations. A formulation comprising of 3% (w/w) chitosan, 10% (w/w) tetracycline HCl and 9% (w/v) tripolyphosphate was identified for maximising bioadhesivity and obtaining controlled drug release. The optimal microsphere preparation was subsequently characterised in terms of hydration dynamics, release kinetics, antimicrobial activity, thermal properties, morphology and surface pH. Kinetic models revealed that drug release followed Fickian diffusion while textural analysis showed minimal hydration over the test period. Antimicrobial studies showed that the drug concentrations in the in vitro release samples were above the minimum concentration of drug required for inhibition of Staphylococcus aureus growth. Thermal analyses showed a possible interaction between the drug and polymer. Scanning electron microscopy confirmed the integrity of the microspheres and identified the morphological changes following drug release. Surface pH of the microspheres was similar to salivary pH and did not show extremes in changes over the test period.

A robust approach to studying the adsorption of Pluronic F108 on nonporous membranes.

A method for poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) desorption from synthetic nonporous polymeric membranes, using hexane:isopropanol treatment and subsequent colorimetric quantification, is described. The polymers polysulfone, poly(vinyldiene fluoride), and poly(ether imide) were used to fabricate solid adsorption matrices. The desorbed Pluronic F108 forms a color complex with ammonium ferrothiocyanate (NH4FeSCN) and is based on partitioning of a chromophore present in NH4FeSCN from an aqueous phase to a chloroform phase in the presence of Pluronic. The protocols for Pluronic desorption and detection are simple, sensitive, inexpensive, rapid, and reproducible over a wide range of Pluronic coating concentrations and membrane surface chemistries. A linear response over the concentration range from 3 to 130 microg ml(-1) is obtained. The adsorption isotherms for flat sheet membranes are also described and the Langmuir equation provides the best fit for the adsorption data obtained within the concentration range studied. The absence of any significant interference from certain proteins, vitamins, carbohydrates, plasma, and halogenated derivatives makes the assay equally suitable for the estimation of Pluronic F108 in the attendant Pluronic conjugates or in biomedical applications. Using nonporous hollow fine fibers and capillary membranes as model curved substrates we were also able to correlate an increase in the radius of curvature with a corresponding increase in the surface interfacial adsorption of Pluronic F108.