A South African central hospital's experience with malignant colorectal obstruction.

BACKGROUND: The spectrum and outcome of colorectal cancer (CRC) presenting with obstruction is not well studied in low- to middle-income countries (LMIC) and could have implications for health policy. This study aimed to address this deficit in an LMIC setting. METHODS: A retrospective analysis was conducted of patients with large bowel obstruction, during the period 2000-2019 from the prospective Inkosi Albert Luthuli Central Hospital (IALCH) CRC registry data. Data analysed included the site of CRC, tumour differentiation, management of patients with obstructive CRC, resection margins post resection, oncological management and reasons for failure to receive oncological therapy. Patient follow-up and recurrence were recorded. RESULTS: Malignant obstruction from CRC occurred in 510 patients (20% of the CRC registry). Median age at presentation was 57 years (IQR 48-67). One hundred and seventy-six (34.5%) and 135 (26.5%) had stage III and IV disease respectively. Moderately differentiated cancer was seen in 335 (65.6%). Management was resection (370; 72.5%), diverting colostomy (123; 24.1%) and stent insertion (55; 10.8%). Twenty-one patients (5.7%) had positive resection margins. Recurrence occurred in 34 patients (6.7%), all of whom had initially undergone resection, giving a recurrence rate of 9.8% in those receiving surgery. Median disease-free interval for patients developing recurrence was 21 months (IQR 12-32). CONCLUSION: One in five patients with CRC presented with obstruction. These patients were younger than in high incomecountry (HIC) series. Over 70% underwent resection. Stomas were used twice as frequently as stents to relieve the obstruction, a finding that is the reverse of that in HICs.

Prevalence of Aflatoxin Contamination in Peanuts and Peanut Butter from an Informal Market, Harare, Zimbabwe.

Peanuts and peanut butter play an important role nutritionally in improving the diets of individuals in many parts of Africa, especially in the fight against child malnutrition. However, in developing countries such as Zimbabwe, most of the raw peanuts and peanut butter produced in backyard industries are sold in informal markets and rarely undergo formal safety inspection for aflatoxin contamination. The objective of the study was to determine the prevalence of aflatoxins in raw peanuts and backyard peanut butter sold at Mbare informal market. Ten (10) raw peanut samples and twenty (20) peanut butter samples were collected from Mbare informal market. Aflatoxin contamination was determined using liquid chromatography-mass spectrometry (LC-MS). The results revealed that sixty percent (60%) of the raw peanut samples were contaminated with total aflatoxin ranging from <0.75 to 426.4 µg/kg. One hundred percent (100%) of peanut butter samples were contaminated with total aflatoxins ranging from 4.7 µg/kg to 435.0 µg/kg. Aflatoxin B1 was the most prevalent aflatoxin in both raw peanuts (range, 1.2 µg/kg to 90.8 µg/kg) and peanut butter (range, 4.7 to 382.9 µg/kg). Forty percent (40%) of the raw peanuts and 95% of peanut butter samples exceeded the maximum limits of AFB1 as set by Zimbabwe legislation. The results suggest that raw peanuts and especially the peanut butter from backyard industries are heavily contaminated with aflatoxins and could constitute a possible health risk to consumers who regularly purchase these food commodities from informal markets.

The use of South African botanical species for the control of blood sugar.

ETHNOPHARMACOLOGICAL RELEVANCE: Diabetes mellitus (DM) is one of the most prevalent diseases globally and is of considerable concern to global health. Approximately 425 million people are estimated to have DM globally and this is predicted to increase to >642 million by 2040. Whilst the prevalence of DM in South Africa is slightly lower than the global average, it is expected to rise rapidly in future years as more South Africans adopt a high calorie "westernised" diet. Traditional medicines offer an alternative for the development of new medicines to treat DM and the usage of South African plants is relatively well documented. AIM OF THE STUDY: To critically review the literature on the anti-diabetic properties of South African plants and to document plant species used for the treatment of DM. Thereafter, a thorough examination of the related research will highlight where research is lacking in the field. MATERIALS AND METHODS: A review of published ethnobotanical books, reviews and primary scientific studies was undertaken to identify plants used to treat DM in traditional South African healing systems and to identify gaps in the published research. The study was non-biased, without taxonomic preference and included both native and introduced species. To be included, species must be recorded in the pharmacopeia of at least one South African ethnic group for the treatment of DM. RESULTS: One hundred and thirty-seven species are recorded as therapies for DM, with leaves and roots most commonly used. The activity of only 43 of these species have been verified by rigorous testing, and relatively few studies have examined the mechanism of action. CONCLUSION: Despite relatively extensive ethnobotanical records and a diverse flora, the anti-diabetic properties of South African medicinal plants is relatively poorly explored. The efficacy of most plants used traditionally to treat DM are yet to be verified and few mechanistic studies are available. Further research is required in this field.

Silicosis and pulmonary tuberculosis in deceased female South African miners.

BACKGROUND: Implementation of South Africa's 2002 Mining Charter increased women's participation in underground mining. However, occupational lung diseases (OLDs) in female gold miners have not been studied. AIMS: To compare autopsy-diagnosed pulmonary silicosis, lymph gland silicosis (a precursor of pulmonary silicosis) and active pulmonary tuberculosis (PTB) in South African gold miners. METHODS: The law allows for autopsies on miners for OLD compensation. Information is stored on the Pathology Automation (PATHAUT) database. We selected records of deceased miners who had worked only in gold mines, started employment from 2002, and were autopsied between 2005 and 2015. Using descriptive statistics, we compared demographic and employment characteristics, and disease proportions by sex. RESULTS: The study comprised 847 gold miners: 68 women and 779 men. There were no statistically significant differences in proportions of autopsy-diagnosed pulmonary silicosis [3 (4%) in women and 54 (7%) in men], lymph gland silicosis [11 (16%) and 171 (22%)] or PTB [29 (43%) and 254 (33%)]. Age and employment duration in women and men with disease were similar. Most miners with pulmonary silicosis had started employment from 2003 [315 (77%)] and worked for under 10 years. CONCLUSION: It is important to report research findings by sex. Proportions of silicosis and PTB were comparable in women and men, suggesting similar exposures. Silicosis detection after short employment indicates inadequate dust control, particularly as most entered the industry after implementation of interventions to control silica dust in 2003.

What causes symptoms suggestive of tuberculosis in HIV-positive people with negative initial investigations?

OBJECTIVE: To identify the causes of symptoms suggestive of tuberculosis (TB) among people living with the human immunodeficiency virus (PLHIV) in South Africa. METHODS: A consecutive sample of HIV clinic attendees with symptoms suggestive of TB (1 of cough, weight loss, fever or night sweats) at enrolment and at 3 months, and negative initial TB investigations, were systematically evaluated with standard protocols and diagnoses assigned using standard criteria. TB was 'confirmed' if Mycobacterium tuberculosis was identified within 6 months of enrolment, and 'clinical' if treatment started without microbiological confirmation. RESULTS: Among 103 participants, 50/103 were pre-antiretroviral therapy (ART) and 53/103 were on ART; respectively 68% vs. 79% were female; the median age was 35 vs. 45 years; the median CD4 count was 311 vs. 508 cells/mm³. Seventy-two (70%) had 5% measured weight loss and 50 (49%) had cough. The most common final diagnoses were weight loss due to severe food insecurity (n = 20, 19%), TB (n = 14, 14%: confirmed n = 7; clinical n = 7), other respiratory tract infection (n = 14, 14%) and post-TB lung disease (n = 9, 9%). The basis for TB diagnosis was imaging (n = 7), bacteriological confirmation from sputum (n = 4), histology, lumbar puncture and other (n = 1 each). CONCLUSION: PLHIV with persistent TB symptoms require further evaluation for TB using all available modalities, and for food insecurity in those with weight loss.

Rapidly increasing body mass index among children, adolescents and young adults in a transitioning population, South Africa, 2008-15.

Background: There is a global epidemic of overweight and obesity; however, this rate of increase is even greater in some low- and middle-income countries (LMIC). South Africa (SA) is undergoing rapid socioeconomic and demographic changes that have triggered a rapid nutrition transition. The paper focuses on the recent rate of change of body mass index (BMI) among children, adolescents and young adults, further stratified by key sociodemographic factors. Methods: We analysed mean BMI of 28 247 individuals (including children) from 7301 households by age and year, from anthropometric data from four national cross-sectional (repeated panel) surveys using non-linear fitted curves and associated 95% confidence intervals. Results: From 2008 to 2015, there was rapid rise in mean BMI in the 6-25 age band, with the highest risk (3-4+ BMI unit increase) among children aged 8-10 years. The increase was largely among females in urban areas and of middle-high socioeconomic standing. Prominent gains were also observed in certain rural areas, with extensive geographical heterogeneity across the country. Conclusions: We have demonstrated a major deviation from the current understanding of patterns of BMI increase, with a rate of increase substantially greater in the developing world context compared with the global pattern. This population-wide effect will have major consequences for national development as the epidemic of related non-communicable disease unfolds, and will overtax the national health care budget. Our refined understanding highlights that risks are further compounded for certain groups/places, and emphasizes that urgent geographical and population-targeted interventions are necessary. These interventions could include a sugar tax, clearer food labelling, revised school feeding programmes and mandatory bans on unhealthy food marketing to children.The scenario unfolding in South Africa will likely be followed in other LMICs.

Childhood Cancers in Zimbabwe: A 10 year review of the Zimbabwe National Cancer Registry data.

OBJECTIVE: To document the pattern of cancer in children (0-14 years) registered in the Zimbabwe National Cancer Registry from 2000-2009. DESIGN: Retrospective descriptive analysis. METHODS: Analysis of data from the Zimbabwe National Cancer Registry for the period 2000-2009. SETTING: The Zimbabwe National Cancer Registry. RESULTS: Childhood Cancer constituted 3.8% of all malignancies recorded at the cancer registry during the study period. The common cancers were: Wilm's Tumour 286 (16.2%), Kaposi Sarcoma 277 (15.7%), Retinoblastoma 231 (13.1%), Non- Hodgkins lymphoma 182 (10.3%), leukemia 158 (8.9%), brain and nervous tissue 107 (6.1%), connective tissue 105 (5.9%), bone 97 (5.5%), Hodgkins lymphoma 57 (3.2%), Non-melanoma skin 33 (1.9%). All the other remaining cancers were 233 (13.2%). Burkits lymphoma constituted only 2% of all cancers. The noted pattern of cancers in this study were compared to patterns from other countries and similarities and differences are discussed. CONCLUSION: This study showed high incidence rates of Nephroblastoma, Retinoblastoma and Kaposi sarcoma. In contrast to high income countries leukemia and brain tumours are more prevalent in older age group. Compared to other countries in Africa, Burkits lymphoma was rare. Further research is required to identify factors that influence relative frequencies in childhood cancers in Zimbabwe. Findings from this study provide baseline data for future studies.

Critical review of research literature on climate-driven malaria epidemics in sub-Saharan Africa.

OBJECTIVES: To obtain a better understanding of existing research evidence towards the development of climate-driven malaria early warning systems (MEWS) through critical review of published literature in order to identify challenges and opportunities for future research. STUDY DESIGN: Literature review. METHODS: A comprehensive search of English literature published between 1990 and 2009 was conducted using the electronic bibliographic database, PubMed. Only studies that explored the associations between environmental and meteorological covariates, El Nino Southern Oscillation (ENSO) and malaria as the basis for developing, testing or implementing MEWS were considered. RESULTS: In total, 35 relevant studies revealed that the development of functional climate-based MEWS remains a challenge, partly due to the complex web of causality and partly due to the use of imprecise malaria data, spatially and temporally varying covariate data, and different analytical approaches with divergent underlying assumptions. Nevertheless, high resolution spatial and temporal data, innovative analytical tools, and new and automated approaches for early warning and the development of operational MEWS. CONCLUSIONS: Future research should exploit these opportunities and incorporate the various aspects of MEWS for functional epidemic forecasting systems to be realized.

Synthesis and structural studies of pentacycloundecane-based HIV-1 PR inhibitors: a hybrid 2D NMR and docking/QM/MM/MD approach.

Pentacycloundecane (PCU) lactam-peptide based HIV protease inhibitors were synthesized and nanomolar activity against the resistance-prone wild type C-South African HIV protease is reported. NMR investigations indicated that the activity is related to the chirality of the PCU moiety and its ability to induce conformations of the coupled peptide side chain. EASY-ROESY NMR experiments gave information about the 3D structure of the cage peptides and 3D solution structure could be linked to the experimental IC(50) activity profile of the considered inhibitors. QM/MM/MD simulations of the inhibitors in solution confirmed the NMR observed conformations. Docking experiments and QM/MM/MD simulations of the inhibitor-HIV PR complexes were also performed. These computational results complimented the experimental inhibition activities and enabled us to report a unique binding mode for PCU-based inhibitors at the active site of HIV-protease enzyme. A conserved hydrogen bonding pattern between the norstatine type functional group of the PCU hydroxylactam and active site residues, ASP25/ASP25', was observed in all active compounds. The biological significance and possible mode of inhibition by PCU-based HIV PR inhibitors discussed herein provide us with a deeper understanding of the mode of action of these novel inhibitors. The PCU-peptides are between 6000 and 8500 time less toxic to human MT-4 cells than Lopinavir. This potentially creates new application avenues for these putative inhibitors to be investigated against a vast number of other disease-related proteases.

Presentation patterns of invasive cancer of the cervix: results from Parirenyatwa Oncology and Radiotherapy Centre, Harare, Zimbabwe 1998-2010.

MAIN OBJECTIVE: The study sought to identify the presentation patterns of invasive uterine cancer of the cervix (CaCx) in Zimbabwe in terms of histology, stage of the disease, ages of patients and socio-economic status. DESIGN: Retrospective study from 1998 to 2010. SUBJECTS: All patients who registered for the first time with invasive CaCx over a systematically selected sample period of four years (1998, 2002, 2006 & 2010). SETTING: The main referral Radiotherapy and Oncology centre in Harare the capital city of Zimbabwe. RESULTS: Majority of patients (91.75%) presented with squamous cell carcinoma, 5.5% presented with adenocarcinomas and 2.75% presented with other types of histology. Late presentation was noted with the majority of the patients (89%) presenting with stage IIB and above. The common ages of patients at presentation were between 40 to 60 years. The majority of the patients (59.5%) were of low socio-economic status. CONCLUSION: In the developed countries CaCx is reducing in frequency, presentation tends to be early, treatment effective and there is decreasing mortality rate from this disease. However in developing countries the situation is not as positive and the disease remains a major concern. This is shown by the presentation pattern of patients with invasive CaCx in Zimbabwe. The patients are shown to present with late stage disease of the squamous cell type, primarily in the age ranges of 40 to 60 years and with the majority of the patients belonging to the low socio-economic status group.

Properties of a new mouthrinse for patients receiving radiation therapy.

INTRODUCTION: Patients receiving radiation therapy due to oral cancer develop complications such as hyposalivation, mucositis, oral infections, dental hypersensitivity and caries. Mouthrinses can alleviate some of these problems. AIMS AND OBJECTIVES: To investigate the in vitro antimicrobial properties and cytotoxicity of an experimental mouthrinse. METHODS: The mouthrinse contained 30% hexylene glycol (glycerine), 7% potassium nitrate and 0.025% sodium fluoride. The minimal inhibitory concentration (MIC) of these ingredients and the mixture was determined for C. albicans, S. aureus and S. mutans over 24 hours at different concentrations. The MICs of two commercial mouthrinses, Corsodyl and Plax, were also determined using the same organisms. All mouthrinses were then tested to determine the percentage kill over 1, 2, and 3 minutes. RESULTS: The MICs for hexylene glycol were 10%, 30% and 10% for C. albicans, S. aureus and S. mutons respectively. Potassium nitrate and sodium fluoride had no antimicrobial effects. The MIC of Corsodyl was 0.016 mg/ml for all the test organisms. The MIC for Plax varied from 0.0002 mg/ml to 0.001 mg/ml. The kill rates for all mouthrinses were acceptable, with no statistical differences between them. The experimental mouthrinse was not toxic to human oesophageal SCC cells after 1 minute exposure. At the time of the experiment, the costs of a similar quantity of the experimental mouthrinse, Corsodyl and Plax were R5.24, R30.00 and R10.00 respectively. CONCLUSIONS: The experimental mouthrinse was cost-effective and proved to have an antimicrobial effect and could be used safely to alleviate oral infections, desensitize teeth, improve oral hygiene and control dental caries in cancer patients after radiation therapy.

Palliative radiation therapy practice for advanced esophageal carcinoma in Africa.

While numerous surveys of pattern of practices of palliative radiotherapy (RT) in advanced esophageal cancers have been published in developed countries, there is no such survey in African countries. During and after a regional training course by the International Atomic Energy Agency (IAEA) in palliative cancer care, a questionnaire was distributed to African RT centers to gather information about infrastructure and human resources available, and the pattern of practice of palliative RT for esophageal cancers. Twenty-four of the 35 centers (60%) completed the questionnaire. Twenty out of 23 (87%) centers treat patients with esophageal cancer presenting with dysphagia using external beam RT (16 centers external beam RT alone and 4 centers also use brachytherapy as a boost). Twelve (60%) centers prescribe RT doses of 30 Gy in 10 fractions and 2 centers 20 Gy in 5 fractions. Eighteen centers (78%) have low dose rate (LDR) brachytherapy, and 9 (39%) centers have high dose rate (HDR) brachytherapy. One center only used HDR brachytherapy alone to a dose of 16 Gy in 2 fractions over 8 days. RT remains a major component of treatment of patients with esophageal cancers in African countries. Still, there is a great variety among centers in both indications for RT and its characteristics for a treatment indication.

Cholangiocarcinoma presenting in an adolescent with vertically acquired HIV infection.

An adolescent with long-standing HIV infection who was severely immunosuppressed during HIV diagnosis developed cholangiocarcinoma 1.5 years after starting antiretroviral therapy.

Antimicrobial resistence of Shigella species isolated during 2004 and 2005 from selected sites in Zimbabwe.

OBJECTIVE: To determine the predominant serotype and antibiotic sensitivity pattern of Shigella isolates during 2004 and 2005 in Zimbabwe. DESIGN: Cross sectional study. SETTING: National Microbiology Reference Laboratory (NMRL), Harare, Zimbabwe. SAMPLE: 259 clinical isolates of Shigella species isolated during 2004 and 2005 in Zimbabwe were studied. These samples had been referred to the NMRL for further testing. MAIN OUTCOME MEASURES: Serotype and antibiotic sensitivity pattern of Shigella species. RESULTS: Of the 259 clinical isolates of Shigella tested the following species were serotyped; 141 (54.4%) were S. flexneri; 70 (27%) S. sonnei; 38 (14.7%) S. dysenteriae and 10 (3.9%) S. boydii. About 4% of all Shigella isolates tested showed full sensitivity to commonly used antibiotics, 20.8% were resistant to one antibiotic only while 75.3% were resistant to at least two antibiotics. The most common resistance among Shigella species was to cotrimoxazole (89%), tetracycline (73%), ampicillin (49%) and chloramphenicol (41%). High susceptibility among Shigella species was observed to nalidixic acid (86%), ciprofloxacin (99%) and ceftazidine (99%). CONCLUSION: There was a low drug resistance of Shigella species to nalidixic acid, a drug of choice in Zimbabwe, except among Shigella dysenteriae type 1 strains. Continuous monitoring of the susceptibility patterns of Shigella species is important in order to detect the emergence of drug resistance and to update guidelines for antibiotic treatment in shigellosis.

Factors associated with tumour stage at presentation in invasive cervical cancer.

OBJECTIVE: The main objective of the study was to determine the demographic, social, clinical, laboratory and histologic factors associated with late stage presentation in cervical cancer. DESIGN: A cross sectional study. SETTING: Government tertiary referral institutions, Harare, Zimbabwe STUDY POPULATION: One hundred consecutive cases of histology proven cervical cancer that presented for treatment between November 2001 and April 2002. MAIN OUTCOME MEASURES: The patients were categorized as early invasive cancer (stage I and II) and late invasive cancer (stage III and IV). RESULTS: The median age of the patients was 48 years (Q1=39 and Q3= 60). Eighty percent presented with late stage disease. Squamous cell carcinoma was the commonest histology (96%) with adenocarcinoma constituting only 4% of all tumours. Poorly differentiated tumour histology and no history of prior cervical cancer screening were found to be significantly associated with late tumour stage at presentation. The odds of presenting with late stage disease in women with a poorly differentiated tumour were 12.97 (95% CI 2.03 to 82.55; p = .007), whilst the odds of late stage presentation in the absence of a history of screening were 11.13 (95% CI 1.33 to 93.21; p = .026). CONCLUSIONS: Intrinsic tumour characteristics were the most important in this population in determining late stage at diagnosis and the value of screening was also highlighted by the results. The odds ratios had wide 95% confidence intervals, thus limiting their usefulness as point estimates.

Radical radiotherapy for carcinoma of the cervix--the Zimbabwean experience.

OBJECTIVE: Carcinoma of the cervix accounts for over 30% of all female malignancies in Zimbabwe. Patients treated with radiotherapy tend to have advanced disease. This study examines some presentation patterns, radiotherapy treatment parameters, outcomes of treatment and identifies some prognostic factors in this set up. DESIGN: Retrospective study. SETTING/SUBJECTS: The study was undertaken on all patients (273) who presented to the Parirenyatwa Hospital Radiotherapy Centre (RTC) between November 1990 and December 1991 with a diagnosis of cervical carcinoma. Of these patients 93 were suitable for radical treatment and they were studied. MAIN OUTCOME MEASURES: Complete remission rates in relation to total dose given and stage of disease, incidence of acute complications, local recurrence and development of metastases. RESULTS: Of the 93 patients studied 72 (77.4%) were Stages I and II and 21 (22.6%) were stage III. Fifty nine percent of the patients gave a history of three to eight months symptom duration and 21.5% symptom duration longer one year. The mean length of follow up time was 13.4 months. The overall complete remission (CR) rate 49%. Ninety seven percent of patients achieving a CR had received 70 Gy or more as total dose to Point A. Patients with both pelvic wall and lower one third vaginal involvement (Stage A + B) did more poorly than other Stage III patients. Acute complications were mainly mild and seen in patients whose overall treatment time was under seven weeks. Most recurrences and metastases occurred within one year of completion of treatment. CONCLUSION: It is only a minority of patients (34.1%) that present to the Radiotherapy Centre with cervical carcinoma who are suitable for radical treatment. These are patients who become aware of their symptoms early. Treatment achieves a good complete remission rate. Follow up of treated patients is poor. The sub group of patients with Stage III A + B must be recognised for their poorer response compared to other patients with Stage III disease.

Traditional smoking of children under five years in Gwanda District

Health workers in Gwanda district have seen children presenting with respiratory infections; measles and diarrhoea with dehydration; whose condition was worsened by the practice of traditional smoking. In traditional smoking; an infant is held over a fire; in which herbs are burnt. Inhalation of the smoke is thought to protect the child against witchcraft and at times is used to treat illnesses. The extent of the practice and its adverse effects have not been known. This study describes the prevalence; methods; indications and perceptions of hazards related to traditional smoking. In a descriptive study 200 mothers; 20 traditional healers and 15 faith healers were selected for interview by a stratified sampling method. In addition; 5 focus group discussions were held with traditional midwives. Doctors in Gwanda district and paediatricians from the referral hospitals in Bulawayo were asked to complete a self-administered questionnaire. The practice of traditional smoking is common in Gwanda district with 98.5of the mothers/guardians interviewed confirming the practice in their villages. The major indication for smoking is for prophylaxis at birth to prepare the child to face the world and to prevent evil spirits.