Dr George Mukhari Hospital

IntroductionSpectral CT is an advanced imaging technique that distinguishes X-ray energies at the detector level to provide energy-resolved images for enhanced tissue characterization and quantitative capabilities. Despite its increasing availability, there is limited information on global clinical use and quality assurance. To address this gap, the International Atomic Energy Agency conducted a global survey to assess current practices and inform future guidance development.MethodsAn online survey was disseminated internationally between October 2024 and June 2025. The questionnaire collected data on the presence and use of spectral CT, quality assurance (QA) and quality control (QC), clinical applications, dosimetry, and training. Responses were analyzed using descriptive statistics.ResultsEighty-three validated responses were received. Only a small fraction of spectral CT systems was photon-counting, nearly all installed from 2024 onward. A wide range of clinical applications was reported, including oncology, urology, cardiology, and neurological imaging. While many institutions reported access to spectral CT, utilization remains limited. Many facilities do not perform dedicated quality control (53%) and retain dosimetry practices (61%). Training gaps—especially among medical physicists—were evident. Respondents cited barriers such as insufficient training, workflow complexity, additional time for image review, limited post-processing tools, and uncertainty about clinical relevance.ConclusionsThis preliminary global survey reveals that while spectral CT access is expanding, its clinical integration and QA/QC practices remain inconsistent. Standardized protocols, targeted training—particularly for medical physicists—and international guidance are urgently needed to support safe and effective adoption of spectral imaging in routine clinical care.Critical relevance statementThis global IAEA survey highlights critical gaps in spectral CT implementation and quality assurance, providing foundational insights that support future clinical advances through standardized protocols, targeted training, and globally harmonized guidance for more effective integration into radiology practice.Key PointsSpectral CT adoption outpaces its clinical use and quality assurance integration.The survey shows limited training, quality control, and routine spectral CT use.Standardized guidelines and targeted training are essential for broader implementation.Graphical

Abstract Background Literature has highlighted the gut microbiota’s role in metabolic functions, suggesting a potential link between gut microbiota composition and T2DM. The purpose of the study was to identify microbial signatures unique to T2DM patients and non-diabetic individuals, to compare microbial profiles between the two groups and to investigate how gut microbiota may be related to inflammation associated with T2DM. Methods A cross-sectional study was conducted involving 51 T2DM patients and 99 non-diabetic South African individuals. Faecal samples were collected and analysed using 16S rRNA gene sequencing to characterize the gut microbiota. Blood samples were obtained to perform HbA1c, CRP and ferritin tests. Bioinformatic and statistical analyses were performed to identify differences in microbial composition and diversity between the two groups. Results The gut microbiota in T2DM patients was predominantly composed of Firmicutes (47.7%), Bacteroidota (37.5%), and Proteobacteria (11.4%), while the non-diabetic group showed a slightly different microbial profile with higher Bacteroidota (41.9%) and a notable presence of Actinobacteriota (4.5%). Abundant families in the T2DM group included Bacteroidaceae (22.8%), Prevotellaceae (7.4%), Enterobacteriaceae (7.4%), Erysipelotrichaceae (6.0%) and Lachnospiraceae (5.2%). The non-diabetic group exhibited dominant families such as Lachnospiraceae 26.7%, Prevotellaceae (25.3%), Bacteroidaceae (12.7%), Ruminococcaceae (9.5%) and Oscillospiraceae (3.8%). At the genus level, Bacteroides (22.8%), Escherichia-Shigella (5.0%), Holdemanella (4.8%), Phascolarctobacterium (3.2%) and Blautia (2.8%) were prevalent in the T2DM group, while Prevotella_9 (22.1%), Bacteroides (12.7%), Agathobacter (6.7%), Blautia (6.3%) and Faecalibacterium (5.1%) were dominant in the non-diabetic group. Differential abundance testing revealed 5 phyla, 16 families, and 25 genera that were either enriched/depleted in T2DM patients relative to non-diabetic individuals. The comparison of alpha diversity metrics between the two groups revealed significant differences across all four measures (P < 0.001), with non-diabetic individuals showing higher values than T2DM patients. HbA1c and CRP levels showed correlations with the relative abundance of various gut microbes at various phyla, family, and genus levels, as well as with all alpha diversity metrics. Conclusion The study revealed distinct differences in gut microbiota composition between T2DM patients and non-diabetic individuals, with T2DM patients showing a higher prevalence of certain phyla, families, and genera linked to metabolic dysregulation. Non-diabetic individuals exhibited greater microbial diversity and beneficial taxa, highlighting a potential protective microbial profile.

BackgroundInfection remains a major cause of morbidity and mortality, regardless of advances in antimicrobial therapy and improved knowledge of microorganisms. With the major global threat posed by antimicrobial resistance, fast and accurate diagnosis of infections, and the reliable identification of intractable infection, are becoming more crucial for effective treatment and the application of antibiotic stewardship. Molecular imaging with the use of nuclear medicine allows early detection and localisation of infection and inflammatory processes, as well as accurate monitoring of treatment response. There has been a continuous search for more specific radiopharmaceuticals to be utilised for infection imaging. This review summarises the most prominent discoveries in specifically bacterial infection imaging agents over the last five years, since 2019.Main bodySome promising new radiopharmaceuticals evaluated in patient studies are reported here, including radiolabelled bacterial siderophores like [68Ga]Ga-DFO-B, radiolabelled antimicrobial peptide/peptide fragments like [68Ga]Ga-NOTA-UBI29-41, and agents that target bacterial synthesis pathways (folic acid and peptidoglycan) like [11C]para-aminobenzoic acid and D-methyl-[11C]-methionine, with clinical trials underway for [18F]fluorodeoxy-sorbitol, as well as for 11C- and 18F-labelled trimethoprim.ConclusionIt is evident that a great deal of effort has gone into the development of new radiopharmaceuticals for infection imaging over the last few years, with remarkable progress in preclinical investigations. However, translation to clinical trials, and eventually clinical Nuclear Medicine practice, is apparently slow. It is the authors’ opinion that a more structured and harmonised preclinical setting and well-designed clinical investigations are the key to reliably evaluate the true potential of the newly proposed infection imaging agents.

Abstract Serum testosterone levels decrease in the aging male, while the risk for prostate cancer (PCa) increases concomitantly. Higher levels in younger men have been linked with racially driven PCa disparities, with African men disproportionately impacted. In turn, higher levels of serum lipids have been associated with aggressive disease, while racial disparity between serum testosterone, cholesterol and cancer mortality has been suggested. Having previously reported a 2.1-fold increased age-adjusted risk for aggressive PCa in Black South African over Black American men, we determined the serum testosterone and associated lipid levels in 250 Black South African men either with or without clinicopathologically diagnosed disease. Observing no associations with serum lipid levels, Black South Africans presented with testosterone levels between 1.24 (< 60 years) and 1.3-fold (≥ 60 years) greater than African Americans. Notably, a rapid drop in total-, bioavailable- and free testosterone levels in men 65 years or older was significantly associated with PCa risk (P = 0.0057, 0.009 and 0.005, respectively), while irrespective of age, further associated with advanced disease (P = 0.004, 0.0012 and 0.0036, respectively). These preliminary data provide insights into the potential role of androgens in driving PCa health disparities, with important consequence for tailoring treatment for Black men.

Hepatocellular carcinoma (HCC) is a major global health problem. Theragnostic is a term that refers to the integration of diagnostic and therapeutic modalities into a single system for personalized medicine. Theragnostic care in HCC involves the use of imaging techniques to diagnose the cancer and assess its characteristics, such as size, location, and extent of spread. Theragnostics involves the use of molecular and genetic tests to identify specific biomarkers that can help guide treatment decisions and, post-treatment, assess the dosimetry and localization of the treatment, thus guiding future treatment. This can be done through either positron emission tomography (PET) scanning or single photon emission tomography (SPECT) using radiolabeled tracers that target specific molecules expressed by HCC cells or radioembolization. This technique can help identify the location and extent of the cancer, as well as provide information on the tumor's metabolic activity and blood supply. In summary, theragnostics is an emerging field that holds promise for improving the diagnosis and treatment of HCC. By combining diagnostic and therapeutic modalities into a single system, theragnostics can help guide personalized treatment decisions and improve patient outcomes.

IntroductionReactivation of hepatitis B virus (HBV) infection induced by immunosuppressive cancer therapy is associated with fulminant liver disease and death. While national guidelines recommend HBV screening and antiviral prophylaxis for patients with cancer prior to initiating immunosuppressive therapy, compliance with these measures is unclear. This study characterized the burden of HBV infection among patients diagnosed with gynecological or dermatological cancers, with or without underlying HIV infection, before initiating immunosuppressive therapy. MethodsBetween 2016 – 2018, we recruited study patients from the Dr George Mukhari Academic Hospital in Tshwane, South Africa. Demographic (age, sex) and clinical data (HIV test results, HIV antiviral regimen, type of cancer) were recorded using a standardized data collection form. All participants were tested for HBV surface antigen (HBsAg), and antibodies to the surface (anti-HBs) and core antigens (anti-HBc). For detection of HBV DNA, a nested polymerase chain reaction was used to amplify polymerase gene fragments which were Sanger-sequenced and analyzed using bioinformatics software. All statistical analyses were performed using R version 4.1.0 (2021-05-18) and R studio version 2022.07.2. ResultsStudy participants were predominantly female (96.3%, 103/107) with a median (IQR) age of 50 (17.5) years. Cervical cancer was the most frequent cancer diagnosis (72%). Over half (52.3%; 56/107) of the participants were HIV positive and all but four (92.9%) on highly active antiretroviral therapy at the time of enrollment. The prevalence of chronic hepatitis B in the study population was 11.2% [95% CI:6.2-19.1], increasing to 14.3% [95% CI:6.8-26.8] in the HIV positive sub-population. The overall prevalence of occult HBV infection was 20% [95% CI:12.8-29.7], 57.9% [95% CI:33.97-78.9] of whom tested negative for all serological markers. Phylogenetic inference showed that all polymerase gene sequences generated in this study were sub-genotype A2. Mutational analysis did not reveal any drug resistance-associated amino acid variations in this study. ConclusionThese findings suggest that chronic and occult HBV infections are more prevalent among cancer patients with or without underlying HIV infection compared to what has previously been reported for the general South African population. This underscores the need to scale-up universal HBV serological and molecular screening with timely institution of prophylaxis prior to initiating immunosuppressive cancer therapy.

BackgroundA broad spectrum of non-neoplastic conditions can radiologically and clinically present as an intracranial tumour. The causes may include infectious diseases such as tuberculosis and non-infectious which may range from benign to malignant tumours. In these cases, a histological diagnosis is crucial since it determines the specific course of treatment the patient needs. MethodsA retrospective study of cerebral tuberculoma diagnosed between 2012 and 2022. The laboratory information system and patient records were used to retrieve the clinico-radiological, pathological, and therapeutic characteristics. ResultsA total of 10 cases cerebral tuberculoma were diagnosed which consisted of men exclusively with mean age of 34.4 years. Human immunodeficiency virus was noted in 70% of the cases, all of which were on antiretroviral therapy. Seizures were the most common symptoms followed by headache. The radiological differential diagnosis ranged from infectious to malignant processes. All the patients underwent successful neurosurgical intervention and received anti-tuberculous treatment with good clinical outcomes. ConclusionCerebral tuberculoma and neoplastic diseases can share clinical and radiological characteristics. In HIV prevalent region, it is crucial to have a high index of suspicion for cerebral tuberculoma. The ability to distinguish between this infection and a neoplastic process by histopathology allows for early and precise therapy, which reduces morbidity and death.

Germline testing for prostate cancer is on the increase, with clinical implications for risk assessment, treatment, and management. Regardless of family history, NCCN recommends germline testing for patients with metastatic, regional, very-high-risk localized, and high-risk localized prostate cancer. Although African ancestry is a significant risk factor for aggressive prostate cancer, due to a lack of available data no testing criteria have been established for ethnic minorities. Through deep sequencing, we interrogated the 20 most common germline testing panel genes in 113 Black South African males presenting with largely advanced prostate cancer. Bioinformatic tools were then used to identify the pathogenicity of the variants. After we identified 39 predicted deleterious variants (16 genes), further computational annotation classified 17 variants as potentially oncogenic (12 genes; 17.7% of patients). Rare pathogenic variants included CHEK2 Arg95Ter, BRCA2 Trp31Arg, ATM Arg3047Ter (2 patients), and TP53 Arg282Trp. Notable oncogenic variants of unknown pathogenicity included novel BRCA2 Leu3038Ile in a patient with early-onset disease, whereas patients with FANCA Arg504Cys and RAD51C Arg260Gln reported a family history of prostate cancer. Overall, rare pathogenic and early-onset or familial-associated oncogenic variants were identified in 6.9% (5/72) and 9.2% (8/87) of patients presenting with a Gleason score ≥8 or ≥4 + 3 prostate cancer, respectively. In this first-of-its-kind study of southern African males, we provide support of African inclusion for advanced, early-onset, and familial prostate cancer genetic testing, indicating clinical value for 30% of current gene panels. Recognizing current panel limitations highlights an urgent need to establish testing guidelines for men of African ancestry. We provide a rationale for considering lowering the pathologic diagnostic inclusion criteria and call for further genome-wide interrogation to ensure the best possible African-relevant prostate cancer gene panel.