Browsing by Subject "Infection"

Now showing 1 - 13 of 13
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    Chronic otorrhoea: Spectrum of microorganisms and antibiotic sensitivity in a South African cohort
    (2013) Meyer, E; Whitelaw, A; Edkins, O; Fagan, J J
    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.
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    Decreasing household contribution to TB transmission with age: a retrospective geographic analysis of young people in a South African township
    (BioMed Central Ltd, 2014) Middelkoop, Keren; Bekker, Linda-Gail; Morrow, Carl; Lee, Namee; Wood, Robin
    BACKGROUND: Tuberculosis (TB) transmission rates are exceptionally high in endemic TB settings. Adolescence represents a period of increasing TB infection and disease but little is known as to where adolescents acquire TB infection. We explored the relationship between residential exposure to adult TB cases and infection in children and adolescents in a South African community with high burdens of TB and HIV. METHODS: TB infection data were obtained from community, school-based tuberculin skin test (TST) surveys performed in 2006, 2007 and 2009. A subset of 2007 participants received a repeat TST in 2009, among which incident TB infections were identified. Using residential address, all adult TB cases notified by the community clinic between 1996 and 2009 were cross-referenced with childhood and adolescent TST results. Demographic and clinic data including HIV status were abstracted for TB cases. Multivariate logistic regression models examined the association of adult TB exposure with childhood and adolescent prevalent and incident TB infection. RESULTS: Of 1,100 children and adolescents included in the prevalent TB infection analysis, 480 (44%) were TST positive and 651 (59%) were exposed to an adult TB case on their residential plot. Prevalent TB infection in children aged 5-9 and 10-14 years was positively associated with residential exposure to an adult TB case (odds ratio [OR]:2.0; 95% confidence interval [CI]: 1.1-3.6 and OR:1.5; 95% CI: 1.0-2.3 respectively), but no association was found in adolescents [greater than or equal to]15years (OR:1.4; 95% CI: 0.9-2.0). HIV status of adult TB cases was not associated with TB infection (p=0.62). Of 67 previously TST negative children, 16 (24%) converted to a positive TST in 2009. These incident infections were not associated with residential exposure to an adult TB case (OR: 1.9; 95% CI: 0.5-7.3). CONCLUSIONS: TB infection among young children was strongly associated with residential exposure to an adult TB case, but prevalent and incident TB infection in adolescents was not associated with residential exposure. The HIV-status of adult TB cases was not a risk factor for transmission. The high rates of TB infection and disease among adolescents underscore the importance of identifying where infection occurs in this age group.
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    Hepatitis C virus infection rate in volunteer blood donors from the Western Cape : comparison of screening tests and PCR
    (1997) Tucker, TJ; Voigt, M; Bird, A; ROBSON, S; Gibbs, B; KANNEMEYER, J; Galloway, M; Kirsch, AE; SMUTS, H
    INTRODUCTION: Hepatitis C virus (HCV) antibody seroprevalence studies overestimate the true infection rate. No data exist on the incidence of HCV or its clinical features in blood donors of sub-Saharan Africa. AIMS: To establish the true incidence of HCV infection in volunteer blood donors in the Western Cape, and compare risk factors and clinical and biochemical features of viraemic and non-viraemic subjects. METHODS: All donors attending the Western Province Blood Transfusion Service between December 1992 and August 1994 were screened prospectively for anti-HCV using the Abbott second-generation assay. Positive donors were evaluated clinically and biochemically. Their sera were examined for HCV-RNA by the polymerase chain reaction (PCR). RESULTS: Of 66314 donors screened, 275 (0.41%) were anti-HCV-positive. Of these 13.6% were PCR-positive (0.056% of all donors). PCR-positive patients had more risk factors for HCV acquisition (P < 0.01), symptoms of hepatitis (P = 0.02) and clinical signs of liver disease (P = 0.05) and higher alanine (P < 0.0001) and aspartate aminotransferase levels (P < 0.0001) than PCR-negative donors. However, clinical and biochemical features did not discriminate adequately between PCR-positive and negative donors. Liver biopsies performed in 9 of 13 PCR-positive cases showed mild inflammation, but no cirrhosis.
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    National sentinel site surveillance for antimicrobial resistance in Klebsiella pneumoniae isolates in South Africa, 2010 - 2012
    (2014) Perovic, Olga; Singh-Moodley, Ashika; Dusé, Adriano; Bamford, Colleen; Elliott, G; Swe-Han, Khine Swe; Kularatne, Ranmini; Lowman, Warren; Whitelaw, Andrew; Nana, Trusha; Wadula, Jeanette; Lekalakala, Ruth; Saif, Adrienne; Fortuin-de Smit, Melony; Marais, Else
    ABSTRACT BACKROUND: The increasing rates of antimicrobial resistance observed in the nosocomial pathogen Klebsiella pneumoniae are of major public health concern worldwide. OBJECTIVES: To describe the antibiotic susceptibility profiles of K. pneumoniae isolates from bacteraemic patients submitted by sentinel laboratories in five regions of South Africa from mid-2010 to mid-2012. Molecular methods were used to detect the most commonly found extended-spectrum beta-lactamase (ESBL) and carbapenemase resistance genes. METHODS: Thirteen academic centres serving the public healthcare sector in Gauteng, KwaZulu-Natal, Free State, Limpopo and Western Cape provinces submitted K. pneumoniae isolates from patients with bloodstream infections. Vitek 2 and MicroScan instruments were used for organism identification and susceptibility testing. Multiplex polymerase chain reactions (PCRs) were used to detect blaCTX-M, blaSHV and blaTEM genes in a proportion of the ESBL isolates. All isolates exhibiting reduced susceptibility to carbapenems were PCR tested for blaKPC and blaNDM-1 resistance genes. RESULTS: Overall, 68.3% of the 2 774 isolates were ESBL-positive, showing resistance to cefotaxime, ceftazidime and cefepime. Furthermore, 46.5% of all isolates were resistant to ciprofloxacin and 33.1% to piperacillin-tazobactam. The major ESBL genes were abundantly present in the sample analysed. Most isolates (95.5%) were susceptible to the carbapenems tested, and no isolates were positive for blaKPC or blaNDM1 There was a trend towards a decrease in susceptibility to most antibiotics. CONCLUSION: The high proportion of ESBL-producing K. pneumoniae isolates observed, and the prevalence of ESBL genes, are of great concern. Our findings represent a baseline for further surveillance in SA, and can be used for policy and treatment decisions.
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    Neurocysticercosis : experience at the teaching hospitals of the University of Cape Town
    (1993) Thomson, AJG
    In the 15 years 1975-1989, 239 patients attending the associated teaching hospitals of the University of Cape Town have been identified retrospectively as having neurocysticercosis. One hundred and twenty-three (51,46%) were children 12 years of age or younger, 14 (5,86%) were adolescents aged 13-19 years, and 102 (42,68%) were adults 20 years of age or older. Two hundred and twelve (88,7%) of these patients were black, almost exclusively Xhosa-speakers originating from the eastern Cape homeland regions of Transkei and Ciskei. Although the clinical features of neurocysticercosis are protean, these patients could be divided into three clinicoradiological groups - a group with seizures, a group with raised intracranial pressure, and an asymptomatic group.In the 15 years 1975-1989, 239 patients attending the associated teaching hospitals of the University of Cape Town have been identified retrospectively as having neurocysticercosis. One hundred and twenty-three (51,46%) were children 12 years of age or younger, 14 (5,86%) were adolescents aged 13-19 years, and 102 (42,68%) were adults 20 years of age or older. Two hundred and twelve (88,7%) of these patients were black, almost exclusively Xhosa-speakers originating from the eastern Cape homeland regions of Transkei and Ciskei. Although the clinical features of neurocysticercosis are protean, these patients could be divided into three clinicoradiological groups - a group with seizures, a group with raised intracranial pressure, and an asymptomatic group.
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    Nitroblue tetrazolium: its use in the diagnosis of infection and in the study of leukocytes, lipoproteins and liposomes
    (1974) Segal, Anthony Walter
    A rapid, objective indicator of pyogemc infection would be of great value in the practice of clinical medicine. On the basis of earlier studies it was claimed that the nitroblue tetrazolium ( NBT) test might fulfill such a role. In view of the potential value of this test, it was reassessed m order to determine its diagnostic accuracy and clinical value. The results obtained in this study did not conform with those previously published. Elevated NBT scores were not diagnostic of pyogenic infection, there was a wide overlap of the results of tests performed on patients with pyogenic disease, patients with other diseases and normal subjects. In addition, there was a significant observer error in the interpretation of the slide preparations. The extent of this error was reduced with experience, but was still considerable in the hands of experienced observers. In the NBT test, the dye enters neutrophils by phagocytosis of NBT in particulate form, complexed to heparin and/or '·fibrinogen. The proportion of neutrophils which phagocytose these complexes seems to be related to the severity of illness of the patient. As serum from these patients is capable of enhancing phagocytosis of complexed dye by normal cells, a humeral factor could be responsible for the increased phagocytosis of complexed NBT indicated by a positive test. , Of the compounds tested, man m vitro model system designed to simulate the NBT test, 3 a,l_acid glycoprotein, immunoglobulins and endotoxin, in concentrations that occur in vivo, enhanced NBT reduction. Any one of these compounds, singly or in combination, could be responsible for positive NBT tests.
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    Plasma vitamin A and zinc levels in HIV-infected adults in Cape Town, South Africa
    (2003) Visser, M E; Maartens, G; Kossew, G; Hussey, G D
    A cross-sectional study of 132 adults attending an HIV clinic in Cape Town, South Africa, was conducted to determine predictors of low plasma vitamin A and Zn levels. No patients were on antiretroviral therapy. The possible confounding effect of the acute-phase response was controlled by including C-reactive protein levels in multivariate analysis and by excluding active opportunistic infections. Retinol levels were low (< 1.05 μmol/l) in 39% of patients with early disease (WHO clinical stages I and II) compared with 48 and 79 % of patients with WHO stage III and IV respectively (P<0.01). Plasma Zn levels were low (< 10.7 μmol/l) in 20% of patients with early disease v. 36 and 45 % with stage III and IV disease respectively (P< 0.05). C-reactive protein levels were normal in 63 % of subjects. Weak, positive associations were found between CD4+lymphocyte count and plasma levels of retinol (r 0.27; 95 % CI 0.1, 0.43) and Zn (r 0.31; 95% CI 0.25, 0.46). Multivariate analysis showed the following independent predictors of low retinol levels: WHO stage IV (odds ratio 3.4; 95 % CI 2.1, 5.7) and body weight (odds ratio per 5 kg decrease 1.15; 95% CI, 1-08, 1.25), while only body weight was significantly associated with low Zn levels (OR per 5 kg decrease 1.19; 95% CI 1.09, 1.30). CD4+lymphocyte count <200/μl was not significantly associated with either low retinol or Zn levels. In resource-poor settings, simple clinical features (advanced disease and/or weight loss) are associated with lowered blood concentrations of vitamin A and/or Zn. The clinical significance of low plasma retinol and/or Zn levels is unclear and more research is required to establish the role of multiple micronutrient intervention strategies in HIV disease.
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    Respiratory microbes present in the nasopharynx of children hospitalised with suspected pulmonary tuberculosis in Cape Town, South Africa
    (2016) Dube, Felix S; Kaba, Mamadou; Robberts, F J Lourens; Ah Tow, Lemese; Lubbe, Sugnet; Zar, Heather J; Nicol, Mark P
    Abstract Background Lower respiratory tract infection in children is increasingly thought to be polymicrobial in origin. Children with symptoms suggestive of pulmonary tuberculosis (PTB) may have tuberculosis, other respiratory tract infections or co-infection with Mycobacterium tuberculosis and other pathogens. We aimed to identify the presence of potential respiratory pathogens in nasopharyngeal (NP) samples from children with suspected PTB. Method NP samples collected from consecutive children presenting with suspected PTB at Red Cross Children’s Hospital (Cape Town, South Africa) were tested by multiplex real-time RT-PCR. Mycobacterial liquid culture and Xpert MTB/RIF was performed on 2 induced sputa obtained from each participant. Children were categorised as definite-TB (culture or qPCR [Xpert MTB/RIF] confirmed), unlikely-TB (improvement of symptoms without TB treatment on follow-up) and unconfirmed-TB (all other children). Results Amongst 214 children with a median age of 36 months (interquartile range, [IQR] 19–66 months), 34 (16 %) had definite-TB, 86 (40 %) had unconfirmed-TB and 94 (44 %) were classified as unlikely-TB. Moraxella catarrhalis (64 %), Streptococcus pneumoniae (42 %), Haemophilus influenzae spp (29 %) and Staphylococcus aureus (22 %) were the most common bacteria detected in NP samples. Other bacteria detected included Mycoplasma pneumoniae (9 %), Bordetella pertussis (7 %) and Chlamydophila pneumoniae (4 %). The most common viruses detected included metapneumovirus (19 %), rhinovirus (15 %), influenza virus C (9 %), adenovirus (7 %), cytomegalovirus (7 %) and coronavirus O43 (5.6 %). Both bacteria and viruses were detected in 73, 55 and 56 % of the definite, unconfirmed and unlikely-TB groups, respectively. There were no significant differences in the distribution of respiratory microbes between children with and without TB. Using quadratic discriminant analysis, human metapneumovirus, C. pneumoniae, coronavirus 043, influenza virus C virus, rhinovirus and cytomegalovirus best discriminated children with definite-TB from the other groups of children. Conclusions A broad range of potential respiratory pathogens was detected in children with suspected TB. There was no clear association between TB categorisation and detection of a specific pathogen. Further work is needed to explore potential pathogen interactions and their role in the pathogenesis of PTB.
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    Respiratory microbes present in the nasopharynx of children hospitalised with suspected pulmonary tuberculosis in Cape Town, South Africa
    (BioMed Central, 2016-10-24) Dube, Felix S; Kaba, Mamadou; Robberts, F J Lourens; Tow, Lemese A; Lubbe, Sugnet; Zar, Heather J; Nicol, Mark P
    Background: Lower respiratory tract infection in children is increasingly thought to be polymicrobial in origin. Children with symptoms suggestive of pulmonary tuberculosis (PTB) may have tuberculosis, other respiratory tract infections or co-infection with Mycobacterium tuberculosis and other pathogens. We aimed to identify the presence of potential respiratory pathogens in nasopharyngeal (NP) samples from children with suspected PTB. Method: NP samples collected from consecutive children presenting with suspected PTB at Red Cross Children’s Hospital (Cape Town, South Africa) were tested by multiplex real-time RT-PCR. Mycobacterial liquid culture and Xpert MTB/RIF was performed on 2 induced sputa obtained from each participant. Children were categorised as definite-TB (culture or qPCR [Xpert MTB/RIF] confirmed), unlikely-TB (improvement of symptoms without TB treatment on follow-up) and unconfirmed-TB (all other children). Results: Amongst 214 children with a median age of 36 months (interquartile range, [IQR] 19–66 months), 34 (16 %) had definite-TB, 86 (40 %) had unconfirmed-TB and 94 (44 %) were classified as unlikely-TB. Moraxella catarrhalis (64 %), Streptococcus pneumoniae (42 %), Haemophilus influenzae spp (29 %) and Staphylococcus aureus (22 %) were the most common bacteria detected in NP samples. Other bacteria detected included Mycoplasma pneumoniae (9 %), Bordetella pertussis (7 %) and Chlamydophila pneumoniae (4 %). The most common viruses detected included metapneumovirus (19 %), rhinovirus (15 %), influenza virus C (9 %), adenovirus (7 %), cytomegalovirus (7 %) and coronavirus O43 (5.6 %). Both bacteria and viruses were detected in 73, 55 and 56 % of the definite, unconfirmed and unlikely-TB groups, respectively. There were no significant differences in the distribution of respiratory microbes between children with and without TB. Using quadratic discriminant analysis, human metapneumovirus, C. pneumoniae, coronavirus 043, influenza virus C virus, rhinovirus and cytomegalovirus best discriminated children with definite-TB from the other groups of children. Conclusions: A broad range of potential respiratory pathogens was detected in children with suspected TB. There was no clear association between TB categorisation and detection of a specific pathogen. Further work is needed to explore potential pathogen interactions and their role in the pathogenesis of PTB.
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    Single-dose benzathine penicillin in infants at risk of congenital syphilis : results of a randomised study
    (1997) Radcliffe, M; Meÿer, M; Roditi, D; Malan, A
    OBJECTIVE: To determine the efficacy of single-dose benzathine penicillin G in infants at high risk of congenital syphilis. DESIGN: Randomised study comparing benzathine penicillin with no therapy. SETTING: Peninsula Maternal and Neonatal Service, Cape Town. SUBJECTS: Asymptomatic infants born to mothers with untreated syphilis whose VDRL titre was 32 or more. OUTCOME MEASURES: The number of cases of congenital syphilis was determined by results of IgM Western blots and follow-up VDRL titres. RESULTS AND CONCLUSIONS: Of 8 patients followed up in the non-treatment group, 4 had congenital syphilis while 0/11 had the disease (P = 0.035) in the group receiving benzathine penicillin. Although the exact failure rate is unknown, benzathine penicillin is effective in preventing symptomatic congenital syphilis when administered to high-risk newborns.
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    The burden of imported malaria in Gauteng Province
    (2010) Weber, Ingrid B; Baker, Lee; Mnyaluza, Joy; Matjila, Maila J; Barnes, Karen; Blumberg, Lucille
    OBJECTIVES: To describe the burden of malaria in Gauteng Province, and to identify potential risk factors for severe disease. DESIGN: We conducted a prospective survey of malaria cases diagnosed in hospitals throughout Gauteng from December 2005 to end November 2006. OUTCOME MEASURES: Malaria frequency, severity, and treatment. Results. We identified 1 701 malaria cases; 1 548 (91%) were seen at public sector hospitals and 153 (9%) at private hospitals; 1 149 (68%) patients were male. Median age was 27 years (range 1 month - 89 years). Most (84%) infections were acquired in Mozambique. Disease severity did not differ by age or sex. Patients who were South African-born were more likely to have severe disease (OR=1.43 (1.08 - 1.91)), as were patients who experienced a delay >48 hours between onset of symptoms and diagnosis or treatment (OR=1.98 (1.48 - 2.65)). While most patients appropriately received quinine, only 9% of severe malaria cases received the recommended loading dose. CONCLUSIONS: The incidence of malaria in Gauteng was higher than previously reported, emphasising the need to prevent malaria in travellers by correct use of non-drug measures and, when indicated, malaria chemoprophylaxis. Disease severity was increased by delays between onset and treatment and lack of partial immunity. Providers should consult the latest guidelines for treatment of malaria in South Africa, particularly about treatment of severe malaria. A change in drug policy to artemisinin combination therapy for imported uncomplicated malaria in non-malaria risk provinces should be strongly considered.
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    Therapeutic efficacy of sulfadoxine-pyrimethamine for Plasmodium falciparum malaria : A study 5 years after implementation of combination therapy in Mpumalanga, South Africa
    (2005) Mabuza, Aaron; Govere, John; La Grange, Kobus; Mngomezulu, Nicros; Allen, Elizabeth; Zitha, Alpheus; Mbokazi, Frans; Durrheim, David; Barnes, Karen
    Objectives. To assess the therapeutic efficacy of sulfadoxine-pyrimethamine (SP) after 5 years of use as first-line treatment of uncomplicated Plasmodium falciparum malaria, and thus guide the selection of artemisinin-based combination therapy in Mpumalanga, South Africa. Design. An open-label, in vivo therapeutic efficacy study of patients with uncomplicated P. falciparum malaria treated with a single oral dose of SP, with response to treatment monitored clinically and parasitologically on days 1, 2, 3, 7, 14, 21, 28 and 42. Setting. Mangweni and Naas public health care clinics, Tonga district in rural Mpumalanga. Subjects, outcome measures and results. Of 152 patients recruited sequentially, 149 (98%) were successfully followed up for 42 days. One hundred and thirty-four patients (90%) demonstrated adequate clinical and parasitological response. Of the 15 patients (10%) who failed treatment, 2 (1.3%) had an early treatment failure, and polymerase chain reaction confirmed recrudescent infection in all 13 patients (8.7%) who had late parasitological (N = 11) or clinical (N = 2) failure. Gametocyte carriage was prevalent following SP treatment (84/152) and this has increased significantly since implementation in 1998 (relative risk 2.77 (confidence interval 1.65 - 4.66); p = 0.00004). Conclusion. Asexual P. falciparum parasites in Mpumalanga remain sensitive to SP, with no significant difference between the baseline cure rate (94.5%) at introduction in 1998, and the present 90% cure rate (p = 0.14). However, since gametocyte carriage has increased significantly we recommend that SP be combined with artesunate in Mpumalanga to reduce gametocyte carriage and thus decrease malaria transmission and potentially delay antimalarial resistance.
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    TNF-dependent regulation and activation of innate immune cells are essential for host protection against cerebral tuberculosis
    (BioMed Central Ltd, 2015) Francisco, Ngiambudulu; Hsu, Nai-Jen; Keeton, Roanne; Randall, Philippa; Sebesho, Boipelo; Allie, Nasiema; Govender, Dhirendra; Quesniaux, Valerie; Ryffel, Bernhard; Kellaway, Lauriston; Jacobs, Muazzam
    BACKGROUND: Tuberculosis (TB) affects one third of the global population, and TB of the central nervous system (CNS-TB) is the most severe form of tuberculosis which often associates with high mortality. The pro-inflammatory cytokine tumour necrosis factor (TNF) plays a critical role in the initial and long-term host immune protection against Mycobacterium tuberculosis (M. tuberculosis) which involves the activation of innate immune cells and structure maintenance of granulomas. However, the contribution of TNF, in particular neuron-derived TNF, in the control of cerebral M. tuberculosis infection and its protective immune responses in the CNS were not clear. METHODS: We generated neuron-specific TNF-deficient (NsTNF / ) mice and compared outcomes of disease against TNF f/f control and global TNF / mice. Mycobacterial burden in brains, lungs and spleens were compared, and cerebral pathology and cellular contributions analysed by microscopy and flow cytometry after M. tuberculosis infection. Activation of innate immune cells was measured by flow cytometry and cell function assessed by cytokine and chemokine quantification using enzyme-linked immunosorbent assay (ELISA). RESULTS: Intracerebral M. tuberculosis infection of TNF / mice rendered animals highly susceptible, accompanied by uncontrolled bacilli replication and eventual mortality. In contrast, NsTNF / mice were resistant to infection and presented with a phenotype similar to that in TNF f/f control mice. Impaired immunity in TNF / mice was associated with altered cytokine and chemokine synthesis in the brain and characterised by a reduced number of activated innate immune cells. Brain pathology reflected enhanced inflammation dominated by neutrophil influx. CONCLUSION: Our data show that neuron-derived TNF has a limited role in immune responses, but overall TNF production is necessary for protective immunity against CNS-TB.