Day: April 1, 2025

Categories : Lab Tests and Imaging Metabolic DisordersTags :

Radiology’s Role in the Diagnosis and Management of Diabetic Complications

On By ModernMedia
SCP -Using modern CT technology, radiologists can search for narrowed arteries in various parts of the body, including the neck and brain. This process is called CT angiography.

Radiology provides crucial insights into the complications caused by diabetes, allowing for timely diagnosis, effective management and monitoring of disease progression. Early detection of these complications can significantly improve patient outcome and quality of life.

What is diabetes?

Diabetes is known as a ‘silent killer’ because it is quite often asymptomatic at the onset. Diabetes, a major lifestyle disorder, has become one of the most dangerous and common diseases in the world. It is a chronic disease that causes high blood sugar levels and occurs when the body doesn’t produce enough insulin or use insulin properly.

Types of diabetes

  • Type 1 diabetes: The body’s immune system destroys the cells that produce insulin
  • Type 2 diabetes: The body doesn’t produce enough insulin or the body’s cells don’t react to insulin as they should
  • Gestational diabetes: Sometimes occurs during pregnancy when the placenta releases hormones that cause insulin resistance. This tampers with the expectant mom’s blood sugar level, changing the amount of glucose in the blood

Around 4.2 million people in South Africa have diabetes – 90% of whom have type 2 diabetes, a lifestyle disease exacerbated by dietary factors, coupled with too little physical activity and high levels of obesity.

Dr Jean de Villiers, senior partner and radiologist at SCP Radiology, discusses the imaging techniques used to identify and manage complications of diabetes.

Cardiovascular Disease: People with diabetes are at higher risk of developing heart disease and other cardiovascular problems. Imaging techniques such as CT angiography can be used to assess the heart’s blood vessels and detect issues such as atherosclerosis, coronary artery narrowing or blockage of the arteries. CT angiography is also used for the neck, arm and leg arteries, as well as the arteries to the gut.

Stroke: Diabetes increases the risk of stroke by damaging blood vessels through high blood sugar levels, leading to the formation of fatty deposits and clots within the arteries. This can increase the chance of clot formation and block blood flow to the brain and cause a stroke. Imaging techniques such as MRI, CT scans, and ultrasound may be able to detect these fatty deposits in the arteries. The deposits are generally seen as areas of narrowing in the involved arteries or calcification of the walls of the arteries.

Blood vessel damage: Chronic high blood sugar levels can directly damage the lining of blood vessels, making them more susceptible to inflammation and clot formation. Essentially, the excess glucose in the blood weakens and stiffens the blood vessel walls, making them more prone to blockages. CT or MRI scans can be critical in identifying and assessing strokes, transient ischemic attacks (TIAs) or other cerebrovascular issues in diabetic patients.

High blood pressure association: People with diabetes often also have high blood pressure, which can exacerbate the damage to blood vessels and increases stroke risk.  A CT of the coronary arteries is used to visualise blockages in the coronary blood vessels and assess the severity of atherosclerosis in diabetic patients. This helps in planning for interventions like stent placement or bypass surgery.

Kidney disease: Diabetes affects your kidneys by potentially damaging the blood vessels within the kidneys due to high blood sugar levels. This can lead to impaired kidney function, causing the kidneys to leak protein into the urine and eventually progressing to chronic kidney disease if left uncontrolled. This condition is often referred to as ‘diabetic nephropathy.’

Diabetic nephropathy can lead to kidney damage and radiology plays a role in assessing kidney size, structure and function. Renal ultrasound can help assess kidney size and detect signs of chronic kidney disease (CKD). In advanced cases, a CT scan or MRI can be used to further evaluate the kidneys for the presence of complications such as renal artery stenosis or renal scarring.

Diabetic neuropathy: Diabetic neuropathy is a complication of diabetes where high blood sugar levels damage nerves throughout the body.  Most commonly affected are the nerves in the legs and feet, leading to symptoms like numbness, tingling, pain and sometimes muscle weakness.  It can also impact internal organs, depending on which nerves are affected and is considered a serious diabetes complication that can affect up to 50% of diabetics.

While radiology is not typically used for direct diagnosis of diabetic neuropathy, it can help rule out other causes of neuropathy. MRI and CT scans can assess for structural issues, such as spinal problems or other nerve impingements that may be contributing to symptoms.

Infections: Diabetic patients have a higher susceptibility to infections due to impaired immune response.

Diabetic foot ulcers and infections: Over time, high blood sugar levels damage nerves, blood vessels and skin in the feet. Damaged nerves can cause loss of feeling in the feet, while damaged blood vessels slow blood flow to the feet, preventing the healing of injuries.

Imaging techniques like CT, MRI and ultrasound are useful for detecting and monitoring bone and soft tissue infections. These can be critical for determining the appropriate course of antibiotic treatment or surgical intervention. X-rays, CT and MRI can be used to assess for infection in diabetic foot, such as ulcers, osteomyelitis or abscesses that may progress to amputation if left untreated.

Liver disease: Non-alcoholic fatty liver disease (NAFLD) is commonly seen in diabetic patients. Ultrasound is the primary tool for detecting fatty liver, while CT and MRI may offer further details on liver fat content or cirrhosis. Regular monitoring through imaging can help prevent more severe liver damage.

Osteoporosis: Long-term diabetes, especially type 1, can increase the risk of osteoporosis due to lower bone density. A DEXA scan helps assess bone mineral density (BMD), aiding in the early detection of osteoporosis and providing information on fracture risk.

‘As with any lifestyle disease, prevention is best. However, second to this is early detection and timely diagnosis, effective management and monitoring of the disease,’ says Dr de Villiers. ‘In the case of diabetes, we work with physicians and patients to detect possible complications early enough to help improve medical care, monitor treatment response and ultimately, improve quality of life.’

Categories : CancerTags :

Three out of Ten Breast Cancers are Detected Between Screenings

On By ModernMedia
Photo by National Cancer Institute

In a new study, researchers from Karolinska Institutet have shown that so-called interval cancers, which are detected between two screening sessions, account for a significant proportion of breast cancer cases and that certain risk factors may increase the likelihood of developing this type of cancer. The study was published in the journal JAMA Oncology.

Mammography screening has been shown to be effective in reducing breast cancer mortality by detecting cancer at an early stage. Despite this, some cancers are not diagnosed during screening but between screening rounds, known as interval cancers. This type of cancer can be more aggressive and difficult to treat than breast cancer detected during a scheduled screening.

The study, which covers half a million women in Stockholm between 1989 and 2020, shows that interval cancer accounts for a significant proportion of all breast cancer cases.

“We found that interval cancers account for about 30 per cent of all breast cancers detected by screening and this percentage has remained constant over three decades, despite advances in screening technology,” says Yuqi Zhang, postdoctoral fellow at the Department of Medical Epidemiology and Biostatistics, Karolinska Institutet and lead author of the study.

The researchers identified several factors that increase the risk of developing interval cancer. These factors include high breast density, hormone therapy, higher education level and older age at first childbirth.

“Women with high breast density and use of hormone therapy are at increased risk of being missed at screening due to false negative results,” says Yuqi Zhang.

Rapid growth of tumour

In addition, the study showed that women with a family history of breast cancer, especially interval cancer, are at a higher risk of developing interval cancer themselves. Women with a family history of breast cancer were 1.9 times more likely to develop interval cancer, and this risk increased to 2.9 times if they had a family history of interval cancer specifically.

“This is often due to the rapid growth of tumours between screening rounds rather than missed detections. The study therefore emphasises the need for more frequent or improved screening methods specifically designed for women with these particular risk factors,” says Yuqi Zhang. 

“Adapting screening protocols to reflect individual risk profiles – whether through more frequent mammography, supplemental imaging like contrast-enhanced mammography, or incorporating genetic testing – could significantly improve early detection rates,” says last author Professor Kamila Czene at the same department. 

“By identifying cancers earlier, we can offer more effective and less invasive treatments, improve long-term survival outcomes, and reduce the emotional and physical toll on patients.”

Source: Karolinska Institutet

Categories : Metabolic DisordersTags :

Fatty Liver Linked to Increased Mortality Risk From Several Diseases

On By ModernMedia
Human liver. Credit: NIH

People with fatty liver disease have almost twice the mortality rate of the general population, according to a comprehensive study from Karolinska Institutet. They have an increased mortality risk from both liver diseases and common diseases such as cancer and cardiovascular disease, according to the study published in The Journal of Hepatology.

In Sweden, it is estimated that one in five people has fatty liver disease known as MASLD (metabolic dysfunction-associated steatotic liver disease), and globally it may be as many as one in four. The disease is caused by overweight or obesity and is characterised by an excessive accumulation of fat in the liver, which can lead to severe liver damage and liver cancer.

Hidden health condition

“Many people are not aware that they have fatty liver disease because it rarely causes any symptoms in the earlier stages,” says Axel Wester, assistant professor at the Department of Medicine, Huddinge, Karolinska Institutet and physician at Karolinska University Hospital. “Our study shows that people diagnosed with MASLD have an increased risk of dying from many different diseases, not just liver disease.”

The researchers identified all patients diagnosed with MASLD in Sweden between 2002 and 2020, more than 13,000 patients in total, and analysed their risk of death from different causes compared to the general population.

The overall mortality rate for people with MASLD was almost twice as high. The risk was elevated for nearly all causes of death studied, but especially for death from liver disease (27 times higher mortality) and liver cancer (35 times higher mortality). However, the most common causes of death were cardiovascular disease and non-liver cancer, with mortality rates 54 and 47 per cent higher, respectively.

A holistic approach

People with MASLD also had an increased risk of dying from infections, gastrointestinal diseases, respiratory diseases, endocrine diseases or external causes, but not from mental illness.

“It is important that we do not only focus on the liver when treating patients with fatty liver disease,” says Hannes Hagström, adjunct professor at the Department of Medicine, Huddinge, Karolinska Institutet and senior physician at Karolinska University Hospital. “A holistic approach and early intervention involving different medical specialities can be crucial to improve the prognosis for these patients.”

Source: Karolinska Institutet

Categories : HIVTags :

8 Million People Living with HIV in SA, According to Latest Estimates

On By ModernMedia
Photo by Miguel Á. Padriñán

By Marcus Low

The number of people living with HIV in South Africa has for the first time reached the eight million mark. Of these, around 6.2 million are on treatment, according to new estimates.

The number of people living with HIV in South Africa continues to rise, surpassing eight million in 2024. This is according to just-released estimates from Thembisa, the leading mathematical model of HIV and TB in South Africa. The eight million amounts to 12.8% of the population.

The continued rise is due to the fact that there are more people becoming newly infected with HIV than there are people with HIV who are dying. The increasing numbers are thus a reflection of the fact that antiretroviral medicines are keeping people alive who would otherwise have died.

There was an estimated 178 000 new HIV infections in 2023/2024 (mid-2023 to mid-2024). Over the same period, around 105 000 people with HIV passed away – 53 000 due to HIV-related causes and 52 000 for reasons not related to HIV.

The estimates of new HIV infections are slightly higher than in last year’s Thembisa publications. According to Dr Leigh Johnson, of the University of Cape Town and the key developer of the Thembisa model, this is mainly due to the model factoring in new evidence that condom usage is declining.

78% treatment coverage

Of the eight million people living with HIV, around 6.2 million, or 78%, were taking antiretroviral treatment in 2024. Around one in five people living with the virus were thus not on treatment. Treatment is recommended for everyone living with HIV.

On the UNAIDS 95-95-95 targets, also endorsed in South Africa’s National Strategic Plan for HIV, TB and STIs 2023 – 2028, the middle target, helping people start and stay on treatment, continues to be the main area of underperformance. Around 95% of people living with HIV in South Africa knew their status in 2024, around 81.5% of these were on antiretroviral treatment, and of those on treatment, around 92% had viral suppression. (Note that the 78% treatment coverage figure is the product of multiplying the performance on the first two 95 targets.)

There continues to be stark gender disparities in South Africa’s HIV epidemic. On the one hand, there are many more women living with HIV than men – 5.2 million compared to 2.6 million as of mid-2024. On the other hand, slightly more men died of HIV-related causes than women in 2023/2024 – 27 100 men compared to 24 200 women.

Worrying trends

One ongoing area of concern is that many people only start treatment once their immune systems have been severely compromised. In 2023/2024, around 54 000 adults started treatment for the first time with CD4 counts below 200 cells/mm3. A CD4 count above 500 cells/mm3 is generally considered to be healthy. CD4 cells are a type of white blood cell that is vital to the functioning of the immune system. People who start treatment with low CD4 counts tend to have worse long-term outcomes.

The latest Thembisa outputs also contain worrying findings on the extent to which people drop in and out of care. In 2023/2024, an estimated 714 000 people restarted antiretroviral treatment after previously having stopped for at least a month – of these, around 326 000 had CD4 counts below 200 cells/mm3.

Finally, on a more positive note, the latest Thembisa outputs continue to show a rise in life expectancy in South Africa. As shown in the above graph, life expectancy declined severely round the turn of the century, largely due to people dying of AIDS, but then increased over time as antiretroviral therapy started keeping people living with HIV alive. The blip in 2020 and 2021 is due to the COVID-19 pandemic.

Note: This article is based on outputs from Thembisa version 4.8 – published in late March 2025. We have quoted 2023/2024 figures since they are based on more data, and thus more reliable than the estimates for 2024/2025. We have rounded some numbers to make the text more accessible. Graphs were made using the R package ggplot2. Spotlight will soon publish an #InTheSpotlight special briefing in which we will unpack the Thembisa 4.8 outputs in more detail.

Republished from Spotlight under a Creative Commons licence.

Read the original article.

Categories : Cancer PaediatricsTags :

Radiopharmaceuticals Being Tested for Brain Tumours in Children

On By ModernMedia
Credit: National Cancer Institute

Neuroblastoma is a rare disease that affects children, often before the age of two. Some are born with the disease. Paediatric surgeon Jakob Stenman is investigating whether targeted radioactive drugs can slow down the disease in those with the most severe form.

Neuroblastoma is a complicated disease, with the most aggressive variant called high-risk neuroblastoma. Children with this disease are treated very intensively. They may undergo surgery, chemotherapy, high-dose chemotherapy with stem cell transplantation, radiotherapy and antibody treatment. Treatment often lasts up to a year and a half.

Despite this, the survival rate is around 60%, according to the Swedish Childhood Cancer Foundation.

“Some relapse in their disease, and we currently lack curative treatment for them,” says Jakob Stenman, a researcher at the Department of Women’s and Children’s Health at Karolinska Institutet.

It is these children, those who have relapsed, that he is treating in a study with targeted radioactive drugs. These are molecules that attach to the surface of cancer cells. These molecules have an appendage: the radioactive substance lutetium-177. The drug first moves through the bloodstream but then attaches to the cancer cells. The emitted radiation damages the cancer cells but unfortunately also the neighbouring healthy cells.

“We have treated ten children so far. Unfortunately, the disease has not disappeared in any of these cases, but it seems to be slowing down, and some benefit more than others from the treatment. When it comes to side effects, the children have tolerated the treatment well,” says Jakob Stenman.

The hope is to be able to prevent relapse

He reports that the interest has been great from clinics in other countries where these children are treated. Hospitals from Lithuania, the Netherlands, the United Kingdom and are now involved.

In neuroblastoma, cancer cells often look very different, even in the same patient. In some metastases, there may be many cells with a surface where the drug attaches, while in other metastases there may be fewer such cells. This means that the targeted drug attaches to fewer cells in some of the metastases. As a result, the local radiation dose is too low in these metastases, which can then continue to grow and spread further.

Jakob Stenman therefore believes that the treatment could be more effective if the radioactive substance used is even more potent, which in this context means that it emits even more energy (ie, radiation). If it then attaches to fewer cells in a metastasis, it might still be able to eliminate all the cancer cells there. But it must act even more locally to protect other tissues from the higher radiation dose.

The researchers have identified several substances they believe could work in this way. These include actinium-225, astatine-211 or lead-212. The effects and side effects of actinium-225 are now being investigated in cell studies and animal experiments. The goal is to start a clinical trial with actinium in three to five years.

“If what we believe turns out to be true, we hope to be able to prevent relapse and thereby enable a cure for a larger proportion of children who have developed high-risk neuroblastoma,” says Jakob Stenman.

Text: Annika Lund for Medicinsk Vetenskap nr 4 2024 

Source: Karolinska Institutet

Categories : Immune SystemTags :

Persistent Parasites are Not Totally Protected from Immune Response

On By ModernMedia
Source: Wikimedia CC0

Most humans have long-lived infections in various tissues, including in the nervous system, that typically do not result in disease. The microbes associated with these infections, such as Toxoplasma gondii, enter a latent stage during which they quietly hide in cells, playing the long game to evade capture and ensure their own survival. But a lack of natural models to study these quiescent stages has led to gaps in scientists’ understanding of how latency contributes to pathogen persistence and whether these stages can be targeted by the immune system.

Now, a team led by University of Pennsylvania School of Veterinary Medicine researchers shows that the immune system indeed recognises the latent stage of the parasite Toxoplasma gondii, which causes toxoplasmosis. The work, published in Nature Microbiology, challenges some common assumptions about how the immune system deals with infections in the brain. Senior author Christopher A. Hunter, professor at PennU Vet, says this knowledge supports the idea that Toxoplasma gondii cysts can be targeted and perhaps even cleared, and the findings have implications for other infections and potential future therapies. The paper also demonstrates how cysts promote the mutual survival of the parasite and host.

In its latent stage, Toxoplasma gondii forms long-lived cysts in neurons in the brain, which helps the parasite evade the host’s immune response. In this study, the researchers found that certain T cells can target neurons containing cysts, thereby promoting parasite control. But there’s a tradeoff: They also found that when cysts are not formed, there is an even higher parasite burden and increased damage to the brain. The study is published in Nature Microbiology.

“There’s this balance of the pathogen needing to take hold in the host but not expand so much that it’s detrimental to the host, because if the host dies, the pathogen may not survive,” says author Lindsey A. Shallberg, who at the time of the research was a doctoral student in Hunter’s lab.

Toxoplasma gondii causes toxoplasmosis, an infection that is asymptomatic for most healthy people but poses a greater risk for those who are immunocompromised or pregnant. It is caused by eating contaminated, poorly cooked meat and by exposure to infected cat faeces, as felines are the only animal in which the parasite can sexually reproduce.

Co-author Julia N. Eberhard, an immunology doctoral student, points to two findings that run counter to preexisting literature and common notions among immunologists. She says scientists long thought that Toxoplasma gondii cysts could hide out in neurons to prevent immune recognition, but this study showed that “neurons aren’t this complete refuge for pathogens.”

This image shows Toxoplasma gondii (red) and a neuron (green) in a mouse brain.
(Image: Courtesy of Anita Koshy)

Eberhard says another commonly held belief was that the parasite needs to form cysts to be able to persist, but in looking at a parasite strain that couldn’t convert to the cyst stage, the researchers found that the immune system did not clear the parasite. They could still identify parasites in mice six months later, which Eberhard found very surprising.

Mathematical modelling independently confirmed experimental findings and indicated that immune pressure on the latent stage of Toxoplasma gondii could explain the observed rise and fall in cyst numbers. This was done by Aaron Winn, a doctoral student in the Department of Physics and Astronomy.

Shallberg says this paper came about because co-author Sebastian Lourido, an associate professor of biology at MIT, had identified the key molecular mechanism that allows the parasite to become latent and wanted to know what would happen if the parasite could not form cysts. In addition, co-author Anita Koshy, a neurologist and scientist at the University of Arizona, had evidence that some neurons could rid themselves of this infection. 

While Toxoplasma gondii is a relevant microorganism to study in and of itself, it is also useful in furthering scientists’ understanding of nervous system infections with latent stages in humans that don’t have mouse models, such as cytomegalovirus. “What makes it special is the fact that it’s a tractable model that we can use in the lab and then apply what we’ve learned to other infections,” Shallberg says.

Looking ahead, Hunter says that his laboratory continues to investigate whether T cells directly recognise the neurons and to study the T cell response in more detail.

Source: University of Pennsylvania