Browsing by Author "Khumalo, Nonhlanhla P"

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    Open Access
    Does hair curl variation influence the efficacy of scalp cooling in the prevention of chemotherapy-induced alopecia in breast cancer patients? A randomized controlled pilot study
    (2021) Obuseng, Odirile; Khumalo, Nonhlanhla P; Naiker, Thurandrie; Thebe, Tselane
    Background: Chemotherapy-induced alopecia (CIA) is a common side-effect of breast cancer treatment. Scalp cooling is reported to reduce CIA; however, it is unknown whether the efficacy is influenced by hair curvature. Methods: This 20-month randomized controlled trial recruited females, (18-65 years) with breast cancer to receive chemotherapy (Adriamycin or Epirubicin and Cyclophosphamide followed by Paclitaxel) with or without scalp cooling. The main outcomes were percentage alopecia (Severity ALopecia Tool scored by 3 dermatologists) in straight versus curly hair and treatment retention rates. Results: Forty-eight patients (24 per group) were randomized; 4 in each group withdrew before study visit1 and photographs of 3 in the cooling group could not be found for severity assessment. Thus 77% constituted the intention to treat population (17 cooling versus 20 control). Agreement on alopecia severity was good overall (ICC=0,94; 95% CI: 0.85 - 0.97) and at 6 of 7 time points. Overall, cooling significantly reduced CIA, relative to no cooling (58.15 ± 28.46 versus 37.29 ± 20.52; p:0.0167), however, percentage alopecia was cosmetically significant. There was no difference in CIA between cooling participants with straight (8) versus curly hair (9), (p:0.0740). The number of patients completing the various cycles of chemotherapy, declined from 77.1% at cycle 1 to 18.8% at cycle 7 for the whole study; from 100% each to 17.6% and 30% for cooling and control groups, respectively (p:0.451). Conclusions: This small study suggests that hair curvature has no significant impact on the efficacy of scalp cooling to reduce CIA, however this requires confirmation.
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    Open Access
    The Epidermiology of Hairstyle related african hair disdorders, in and Urban Township in South Africa
    (2007) Khumalo, Nonhlanhla P; Ehrlich, Rodney; Jessop, S
    The hair of indigenous people of Africa varies from the north to the south of the continent. Although the variation in hair colour from light brown to black occurs, the most significant difference is in the curls which are tightest, and spiral, in indigenous sub Saharan Africans. African hair for the purpose of this thesis refers to the latter hair phenotype. The unique morphology of this hair type is associated with specific responses to grooming. In addition hairstyle preferences may be influenced by politics and fashion. Specific scalp disorders have been anecdotally reported to be more prevalent in Africans. These are acne (folliculitis) keloidalis (AKN), central centrifugal cicatricial alopecia (CCCA) and traction alopecia (TA). For many years all these conditions have been suspected to have a causal association with hairstyles. However, preliminary investigation suggested a lack of population studies demonstrating the latter association. In addition the possible influence of the unique African hair follicle on disease pathogenesis had not been determined. The aims of this thesis were to: Present a systematic 1. literature review of published prevalence and incidence data on the above three conditions. 2. Conduct cross sectional studies to investigate the prevalence of AKN, CCCA and TA in a population of school children and adults and the prevalence of different hairstyles, and to describe any associations between hairstyles and disease. 3. Develop and test for reliability a new severity scoring system for TA the commonest of the above conditions [the marginal traction alopecia severity (M-TAS) scoring instrument]. 4. Evaluate the determinants of both TA presence and severity in African females using data from our cross sectional studies in school children and adults.
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    Open Access
    Human scalp hair: geometry, biochemistry, growth parameters and mechanical characteristics
    (2016) Mkentane, Kwezikazi; Khumalo, Nonhlanhla P; Davids, Lester M
    Scalp hair is increasingly being used as a testing substrate for toxins and monitoring treatment adherence. The biochemistry of human hair is assumed to be similar; however, a recent study reported higher concentration of lipids in African hair. The effect of hair curvature, if any, on drug incorporation (e.g. lipid soluble drugs) is unknown. Racial description of hair morphology is unscientific. A geometric classification of hair into 8 groups (I-straight to VIII-tightly curly) was recently proposed, however its reliability has not been confirmed. The aim of this thesis was to investigate the reliability of the geometric classification (and to assess whether it could be improved) and investigate relationships between morphology and other hair characteristics. Virgin hair was collected from 128 volunteers using a standardized protocol. Geometric measurements of hair using published templates were conducted for classification. Reliability was assessed using Kappa statistics. Characteristics assessed included mechanical properties (miniature tensile tester), growth rate and hair density (TrichoScan® trichogram), biochemistry (Vanillin assay for lipids and Fourier Transform Infrared adsorption) and imaging (Electron and Fluorescent Light Microscopy). Inter-observer agreement was poor for 8-groups (k=0.418) but improved for 6-groups (k=0.671). The intra-observer agreement also improved [ranges: k=0.444 to 0.648 (8-groups) and k=0.599 to 0.836 (6-groups)]. The yield strength of all hair groups was higher than reported for racially grouped samples. Curly hair groups had lower growth rates and tensile strengths. The TrichoScan based growth rate was for fastest for the straightest (0.72±0.3 cm/month) and slowest for the curliest (0.39 ± 0.2 cm/month) hair. No correlation with biochemistry was detected for either the 8 or 6-group classification, although a trend toward higher absorption of lipid (C-H) bands was noted for curly hair. A supervised statistical approach applied to 4 hair groups using the FTIR data improved classification success to 79% (range: 69% - 88%), which needs confirmation but would be more objective than using race for hair testing in Medicine and Forensic Science. This thesis supports a geometric classification with fewer groups (6, based kappa statistics and 4, based on biochemistry); it is also the first to report correlations between hair geometry, biochemistry and physical properties.
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    Open Access
    “Next generation sequencing identifies mutations in GNPTG gene as a cause of familial form of scleroderma-like disease”
    (BioMed Central, 2017-12-29) Arowolo, Afolake T; Adeola, Henry A; Khumalo, Nonhlanhla P
    A letter to the editor making some recommendations on the article entitled “Next generation sequencing identifies mutations in GNPTG gene as a cause of familial form of scleroderma-like disease”.
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    Open Access
    Primary cutaneous malignancies in the Northern Cape Province of South Africa: A retrospective histopathological review
    (2018) York, Katherine; Khumalo, Nonhlanhla P; Dlova, Ncoza; Mosam, Anisa
    Background: Excessive sun exposure and high human immunodeficiency virus prevalence increase skin cancer risk in South Africa. Objective: To describe the nature and extent of skin cancers presenting in public and private health sectors of the Northern Cape Province. Methods: A retrospective analysis of histologically-confirmed new primary cutaneous malignancies from 1/1/2008 to 31/12/2012 was conducted using public and private health sector databases. Types, quantity and distribution of common invasive malignancies by population group, age, gender, anatomical site and health sector were explored. One-year cumulative incidence was calculated and logistic regression models were used to analyse incidence and melanoma thickness trends. Results: 4270 biopsies (14 cutaneous malignancies) were identified. Most common were Squamous Cell Carcinoma (SCC), Basal Cell Carcinoma (BCC), Kaposi Sarcoma (KS), Cutaneous Malignant Melanoma (CMM) and Basosquamous carcinoma. The odds of a White male developing SCC increased by 8% each year (OR: 1.08; CI: 1.01-1.15; p-value: 0.022) whilst the odds of a Black male developing SCC and KS decreased by 9% (OR: 0.91; CI: 0.84-0.99; p-value: 0.033) and 18% (OR: 0.82; CI: 0.70-0.97; p-value: 0.022) each year, respectively. SCC and CMM were diagnosed at more advanced stages within public versus private sectors. CMM is being detected earlier, as indicated by low stage depth increasing by 72% annually (OR: 1.72; 95% CI: 1.04-3.01; p-value: 0.042). Conclusion: Results suggest that reported skin cancer patterns are changing. There is a need for further research and equitable appropriation of financial resources and effort toward developing primary skin cancer prevention initiatives in South Africa.
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    Open Access
    The Use of Hair Cortisol as a Biomarker of Chronic Stress in Patients with a recent Acute Myocardial Infarction
    (2018) Mabotha, Ernest Magee; Van Wyk, Jennifer; Khumalo, Nonhlanhla P
    Background Acute Myocardial infarction (MI) or heart attack is a leading cause of death worldwide. Since an MI is a stressful life event, plasma cortisol levels are expected to increase significantly from the baseline. Cortisol and dehydroepiandrosterone (DHEA) as products of the hypothalamicpituitary-adrenal (HPA)-axis have been used to diagnose endocrine disorders in serum, urine and saliva. However, these body fluids reflect short-term assessments. Hair is a promising alternative and offers several advantages over serum e.g. hair collection is painless, provides a longer detection window (days to months depending on length) and is easy to store. Recent studies confirm good correlation between hair cortisol levels and validated stress questionnaires (i.e., hair cortisol is a biomarker of stress). It is unclear whether stress is a result or cause of acute MI (i.e., chicken or egg). The primary aim of this study was to determine whether hair cortisol is higher in patients with acute MI versus healthy controls and whether the higher levels pre-date acute MI (i.e. is hair cortisol a reliable biomarker of chronic stress that predates acute MI). Methods This pilot study aimed to include 25 age-matched controls and acute MI cases, both 25 STelevation myocardial infarctions (STEMIs) and 25 non-ST-elevation myocardial infarctions (NSTEMIs). Complete versus partial coronary artery occlusion is associated with STEMIs and NSTEMIs respectively. Cortisol levels were measured in 3 cm segments of hair representing 9-12 months of growth (which would be before the heart attack in acute MI cases). The proximal 3 cm closest to the scalp, is estimated to represent 3 months before heart attack. The samples were prepared and analyzed for cortisol concentrations using an enzyme-linked immunoassay kit. In addition, at least three strands of hair from each participant were mounted on a glass slide and subjected to Fourier-Transform Infrared (FTIR) spectroscopy. For cortisol concentrations two-sample Wilcoxon rank-sum (Mann-Whitney) was used for within an individual comparisons and Kruskal-Wallis test was used for within group comparisons (P<0.05 considered significant) For FTIR data Principal Component Analysis (PCA), Orthogonal Projections to Latent Structures Discriminant Analysis (OPLS-DA) and Partial Least Squares (PLS) models were used to compare groups. Results Of the intended sample size of 75, 64 participants (48 acute MI cases and 16 healthy controls) were recruited. The total hair cortisol concentration was significantly higher in acute MI cases than controls [median 23.66 (3.73-209.18) vs. 3.32 (0.37-11.24) pg/mg], (p<0.001), and higher in the hair of STEMI versus NSTEMI cases[35.18 (8.15-209.180 vs. 17.24 (3.73-148.22) pg/mg], (p< 0.01). Further, cortisol levels were similar in proximal versus distal hair segments (within an individual) of STEMIs (p< 0.05) but significantly different in those of NSTEMIs [29.64 (5.87- 148.42) vs 9.94 (5.15-32.95)], (p=0.002). In view of the fact that all 16 controls included were female, the analysis was repeated to include only female study participants[16 controls and 27 cases (10 STEMIs and 17 NSTEMIs)]. The total hair cortisol concentration was also significantly higher in female acute MI cases than controls [median 21.59 (3.73-209.18) vs. 3.32 (0.37-11.24)], (p< 0.001), as well as higher in the hair of STEMI vs. NSTEMI cases [median 37.21 (8.15-209.18) vs. 14.11 (3.73- 148.22pg/mg], (p< 0.05). Further, cortisol levels were similar in proximal versus distal hair segments of STEMIs (p< 0.05) but significantly different in those of NSTEMIs [median 15.26 (5.91-100.41) vs. 9.94 (3.73-37.57)], (p< 0.01). Controls had the lowest cortisol levels and there was no significant difference between proximal and distal hair within the individuals [median 3.18(1.43-7.09) vs. 2.30 (0.68-4.62) pg/mg], (p> 0.05). For FTIR data, OPLS-DA showed a separation between acute MI cases and controls, as well as a separation between STEMIs and NSTEMIs. Further, there was also good correlation between total cortisol concentrations and FTIR spectral data (correlation coefficient = 0.85). Study limitations Although not all intended participants were recruited during the study period, repeating the analysis for only female participants did not alter the findings. Discussion and Conclusions Hair cortisol levels were higher in acute MI cases than controls and significantly higher in STEMIs versus NSTEMIs. Further, FTIR data separated acute MI cases from controls and correlated with cortisol concentrations. Patients with Cushing Disease (CD) are reported to have a higher prevalence of thromboembolic events compared to Cushing Syndrome from adrenal sources, this is thought to be a result of high cortisol levels associated with CD. In this study, STEMIs had the highest cortisol levels which not only predated the acute MI but were unchanged in hair segments correlating with the preceding 9 months (i.e., were chronically consistently high). Interestingly, high cortisol levels also predated the acute MI but more than doubled in the proximal 3 cm hair segments (correlating with 3 months) before the heart attack in NSTEMIs. This study suggests that based on hair cortisol concentrations as a biomarker, chronic constantly high stress predates STEMIs. Although also high in NSTEMIs it is lower than in STEMIs and more than doubles before the onset of an acute MI. The effects of chronic very high cortisol levels on the thromboembolic pathway may be to cause complete (versus partial) coronary artery occlusion in STEMIs. These results require validation in larger studies.
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    Open Access
    The use of collagen IV immunohistochemistry in the diagnosis of bullous pemphigoid
    (2017) De Silva, Roxanne; Khumalo, Nonhlanhla P; Ngwanya, Mzudumile R
    Background: Autoimmune bullous dermatoses present with overlapping clinical features that require histopathological correlation. Immunofluorescence is the most routinely used reliable investigation for diagnosis but requires specialised equipment and is technically sophisticated. Collagen IV immunohistochemistry is reported as a reliable test for the diagnosis of epidermolysis bullosa acquisita whereby It stains the roof of a subepidermal blister and would be expected on the floor in bullous pemphigoid. This technique could be performed as an easily accessible alternative to direct immunofluorescence and has been used anecdotally at our hospital. Aim: To investigate whether collagen IV immunohistochemistry can be used as a reliable histopathological confirmation of bullous pemphigoid. Methods: Two major investigations: 1. A systematic literature search was undertaken of all studies describing the use of collagen IV immunohistochemistry and those comparing it with immunofluorescence in the diagnosis of bullous pemphigoid. 2. A retrospective study of patients diagnosed with bullous pemphigoid over 12 years seen at Groote Schuur Hospital was performed. Patient records that had results for both direct immunofluorescence and collagen IV immunohistochemistry were selected. The positive percentage agreement was calculated. Results: 1. Two studies were found that investigated the use of collagen IV immunohistochemistry in bullous pemphigoid. All reported 33 (100%) cases demonstrated collagen IV at the floor of a subepidermal blister. Of these, 25/25 cases were in agreement with direct immunofluorescence and 7/8 with indirect immunofluorescence which were used as reference standard investigations. 2. In this study, collagen IV was positive in 96% (79/82) of cases and direct immunofluorescence was positive in 85% (72/82) of cases. A positive percentage agreement of 80.5% suggested a strongly positive test accordance. Limitations: 1. The literature search was limited to articles written in english only. 2. The retrospective design and the lack of controls without bullous pemphigoid made it impossible to calculate sensitivity and specificity as well as the kappa statistic. Conclusion: Collagen IV immunohistochemistry is a valid, simple and widely available test which demonstrates accordance with routinely used direct immunofluorescence in the confirmation of bullous pemphigoid. Through clinical and histomorphological correlation, it may be a useful test in resourcelimited settings without facilities for direct immunofluorescence. However, larger controlled studies are warranted to confirm this.