Birt-Hogg-Dubé syndrome (BHD) is a rare inherited condition associated with changes in the gene folliculin (FLCN). Most people are diagnosed through a genetic test to check for changes in the FLCN gene. However, a small proportion of people do not have a detectable change (or variant) in FLCN. This group of people can still be diagnosed with BHD based on the presence of clinical criteria. Features of BHD include skin lesions called fibrofolliculomas, lung cysts and collapsed lungs and an increased risk of kidney cancer.

A recent study described an individual who was initially diagnosed with BHD. They came to the clinic aged 33 with multiple skin lesions. These included fibrofolliculomas on the face and chest, skin tags, lesions in their mouth and multiple lipomas. They had no lung cysts but had one small kidney cyst. They were diagnosed with BHD based on the presence of fibrofolliculomas, but genetic testing did not find a FLCN variant. There was a family history of lipomas, other skin lesions and kidney cancer. By the age of 48, they had more than 50 lipomas surgically removed and many more still present. The patient then consented to whole exome sequencing to search for changes in other genes that might be responsible for these features. A variant in a gene called PRDM10 was found. The same change was also found in affected family members.

The authors of the study then looked at the function of PRDM10 in cells. They made cell lines (cells grown in a laboratory) that contained the PRDM10 variant. PRDM10 is proposed to function as a transcription factor. Transcription factors function to turn genes on and off to control which proteins are produced. The particular mutation in PRDM10 that this family was found to have is in a part of the protein important for turning on target genes. In a previous study in mice, it was shown that PRDM10 can turn on the FLCN gene. In this study, the authors found the same effect in human cells. This was confirmed in cells with the PRDM10 variant where the levels of FLCN were almost undetectable. They compared the cells with the PRDM10 variant to cells that were lacking FLCN and found many of the same changes. This included an increase in a protein called GPNMB which has been found in high levels in kidney tumours from people with BHD.

Linking their work in the lab back to the features found in the patient and their family, the authors suggested that the fibrofolliculomas and kidney cancer could be due to the reduction in FLCN. However, there were no lung cysts present which is a common feature of BHD. It was suggested that perhaps the levels of PRDM10 are lower in the lung than the skin and kidney. The levels of FLCN in cells may be under control of multiple different transcription factors. Lipomas were a very common feature in this patient and their family. It is yet to be discovered how the PRDM10 variant drives the formation of these. PRDM10 is likely to control other genes aside from FLCN. Although lipomas have been found in people with BHD, the authors thought that a loss of FLCN was unlikely to be responsible for this.

In summary, the authors of this study have identified a new syndrome with overlapping features of BHD. However, more work is needed to fully understand the role of PRDM10 in the development of this new condition. Identification of other families with the same variant in PRDM10 would also strengthen the data provided in this study. At the BHD Foundation, we found this study interesting as it increases our knowledge of BHD and similar conditions. We look forward to seeing future work on this, and potentially the identification of new BHD-like conditions.

As we put together a calendar of events for 2023, we reflect on our achievements from the last year. After the relaunch of the BHD Foundation in 2021, we were keen to drive the charity’s efforts to fund research and provide support for people with Birt-Hogg-Dubé syndrome (BHD) in 2022 and beyond. We are proud of what we achieved last year and would like to thank everyone who contributed to our work.

Here, we share our 2022 highlights.

Events

We kickstarted 2022 with a ‘Meet the Expert’ event hosted by the BHD Foundation team. We shared our achievements from 2021 and set out our plans for 2022. We then held 2 further ‘Meet the Expert’ events. In April, Dr Ed Cowen (NIH, USA) shared his work on BHD and the skin. We also held a panel discussion in July on BHD, genetics and pre-implantation genetic testing/IVF.

Join us for our next Meet the Expert with Professor Lisa Henske on February 1^st. Lisa will be talking about her work on BHD and lung cysts. Get your free ticket now.

Our biggest event of 2022 was the BHD Community Symposium. This symposium was the first deliberately designed to be accessible to all members of the community. We were thrilled to welcome people with BHD and their families alongside clinicians and researchers to further connect the community. We were delighted to have over 200 people registered from 22 countries across 5 continents for this virtual event. Read the research and patient-focused highlights.

Research and Conferences

One of our proudest achievements of 2022 was launching the BHD Syndrome International Registry (BIRT) at the end of March. We launched BIRT with the aim of driving forward research and giving people with BHD the opportunity to participate in research. We now have over 200 people registered and we look forward to this growing over the coming years. Read our 6 month registry update.

We took part in several conferences this year to raise awareness of BHD among researchers and clinicians. We developed a BHD awareness leaflet (a printable version is also available) that was shared on a virtual platform at the European Respiratory Society Congress and WONCA, the general practitioner conference. We were also delighted to be able to present our work on BIRT at the European Conference on Rare Diseases and the 4^th International Conference on Rare Diseases.

We were also delighted to announce our grant holders from 2021 in February. We also held another grant funding round in 2022 and will be announcing our new grant holders very soon. Research is an integral part of our work at the Myrovlytis Trust and BHD Foundation. Advancing research into BHD is important so that we can better understand it and develop new treatments

Raising Awareness and Social Media

2022 was also a busy year for getting involved in social media and raising awareness of BHD to the wider community. In January, we took part in Medics 4 Rare Diseases ‘Mystery Monday’ which educates future doctors about rare diseases. We also took part in Rare Disease Day and led the World Pneumothorax Day campaign. We got to share personal stories of BHD on these days including Lea’s story ‘From Lung Collapse to Ironman’ and Joanna’s story  ‘Married on a Mountain with a Collapsed Lung’. We look forward to taking part in these events in 2023 and sharing more of your inspiring stories.  

Read more about our work raising awareness of BHD in 2022.

Fundraising

We were thrilled to launch our fundraising programme this year. We held a Prize Draw this year and raised over £650 towards a new BHD Foundation website. There are several other ways you can get involved and we would love to hear your fundraising ideas!

We would like to say a huge heartfelt thanks to everyone who got involved with us in 2022 and can’t wait to continue building and supporting the BHD community in 2023 and beyond.

At the end of 2022, we sent out a survey to the BHD community about our work at the BHD Foundation. We wanted to make sure you had a say in the projects that we prioritise in 2023.  In this blog, we summarise some of the common themes and ideas highlighted by the survey and how we are addressing them.

Connecting with Others

You said:

• You would be interested in meeting other people with BHD.
• You would be interested in face-to-face conferences.
• You enjoy the Meet the Expert sessions and are most interested in hearing from lung and kidney experts and BHD researchers.
• You would like a list of BHD specialists in different countries.

We did:

• We direct all new BHD patients to the BHD patient led Facebook group where they can share experiences, ask for advice and connect with others.
• We have confirmed a date for the 2023 BHD Research Symposium. This year’s event will be aimed at clinicians and researchers. We also encourage patients to attend as an opportunity to learn more about the latest research. The symposium will be hosted both in person and online. More details about this will be announced soon.
• We have confirmed a date for the first Meet the Expert Session of 2023. On Wednesday 1^st February we will be joined by Lisa Henske. She will be talking about her research into BHD and lung cysts. Register now.
• We have an interactive map where you can search for BHD experts. We have also added an option to download a list of BHD experts in different countries.

We are planning:

• To explore creating a ‘virtual coffee’ morning. These virtual meetings will be a platform where people with BHD can meet and share their experiences. If you are interested in helping with these sessions get in touch with us at contact@bhdsyndrome.org.
• To host a dedicated patient conference every other year following the success of the BHD Community Symposium in 2022. This will include opportunities to connect with researchers, clinicians and other people with BHD.

Medical Records and Research

You said:

• You would like to hear more about current research.
• You would like to be involved with research.
• You would like to see more research in the following areas:
  • non-kidney cancers
  • genetics
  • skin
• You said that research reports are not always accessible to people who do not have research backgrounds. 
• You would like information on the difference between cysts and tumours.
• You would like all your medical records to be in one place.

We did:

• We have a weekly blog post. We blog about the majority of new BHD research that is published.
• We launched the BHD Syndrome International Registry (BIRT) which will help to advance research into BHD. Anyone with a BHD diagnosis can take part and contribute to research. 
• We established the first BHD patient advisory board. This year they will be involved in reviewing grant applications to ensure the research we fund is relevant and impactful for people with BHD.
• We are currently funding several research projects into different aspects of BHD. This includes a project looking at BHD genetics and a project looking at the skin. We are in regular contact with our grant holders and will keep you up to date with these research projects.
• We are PIF TICK accredited and complete a yearly assessment. This means that we have processes in place to ensure that any new resources we make are accessible to people with non-research backgrounds. This includes involving members of the BHD community (patients and experts) throughout the development and testing of new resources.  

We are planning:

• To announce our 2022 grant holders very soon so you can find out more about our newly funded research.
• To explore how best to support people to get involved with research.
• To soon announce our 2023 research funding call.
• To redesign the BHD website and include information on a range of topics based on your feedback.  For example, the difference between tumours and cysts. If you have anything you’d like to see on the new website let us know at contact@bhdsyndrome.org.   
• To explore different platforms where you can upload medical records.

BHD Syndrome International Registry (BIRT)

You said:

• You would like to know where you can find information about BIRT.
• You would like to share the link to the BHD registry.
• You have concerns about sharing personal information in the BHD registry.
• You would like the registry to be available in multiple languages.
• You would like more information on how to navigate BIRT and how the data is used for research.   

We did:

• Information about the BHD registry can be found on the BHD Foundation website. We will be updating the BHD Foundation website this year and will ensure that the registry is clearly signposted.
  • Link to information about the registry: https://bhdsyndrome.org/for-families/bhd-syndrome-international-registry/
• We are very happy for you to share links to the registry.
  • Link to the registry: https://birt.healthie.net/register
• The Pulse Infoframe platform follows rigorous, international regulatory data standards and ensures the highest data security and privacy.
• The registry will soon be available in French, German and Spanish.

We are planning:

• To write a FAQ on BIRT that will address all your questions. The blog will be published in February. Until then please contact us at contact@bhdsyndrome.org with any questions.

Awareness

You said:

• It can be challenging to talk to family members about BHD.
• We need to raise awareness of BHD among doctors.  

We did:

• We have a letter that you can give to family members that explains what BHD is and information about genetic testing.
• We created a BHD symptom leaflet for doctors.
• We are preparing for Rare Disease Day 2023 and World Pneumothorax Day 2023. These days will help to raise awareness of BHD.

We are planning:

• To present and exhibit at conferences to raise awareness of BHD among doctors.

We will continue to review the feedback as the year progresses and update you on our progress. Thank you to everyone who took part in the survey. We wish you all a wonderful start to the new year.

The Myrovlytis Trust and BHD Foundation would like to say a massive thank you to everyone who has got involved with our work this year! We are very grateful to each of you for sharing your story, taking part in World Pneumothorax Day, attending our Meet the Expert events and our first every community-focused symposium. We look forward to seeing as many of you as possible at our 2023 events to raise awareness and drive forward research into BHD together.

We are always keen to receive your feedback about what you would like to see from us in the future. We would greatly appreciate it if you could complete this short survey and let us know what is important to you. The survey will close on Tuesday 3^rd January. Take the survey now.

We also launched our fundraising programme this year and are extremely thankful to the community for helping us to raise money towards a new BHD website which we will be launching next year. We look forward to hearing your fundraising ideas in 2023.

Our offices will be closed from Friday 23^rd December 2022 and will reopen on Tuesday 3^rd January 2023. We will respond to any enquiries upon our return.

From all of us at the Myrovlytis Trust and BHD Foundation, we wish you a wonderful holiday season and a happy new year!

Kidney cancer occurs in up to 1 in 3 people with Birt-Hogg-Dubé syndrome (BHD). Normally, any kidney tumours are surgically removed if they reach 3 cm in size. Surgeons will aim to preserve as much of the kidney as possible.  This is because people with BHD may need multiple surgeries. However, surgery may not always be the best option. For example, the tumours may be in a part of the kidney that is difficult to operate on or in which surgery would lead to reduced kidney function. Therefore, alternative options to surgery for BHD kidney cancer are needed. A report was published looking at the outcomes of people with BHD who underwent percutaneous thermal ablation (PTA) to treat their kidney cancer.

What is percutaneous thermal ablation?
PTA is a non-surgical procedure that uses extreme heat or cold to destroy cancer cells. It is used to treat many different cancers. However, it is not routinely used in the treatment of BHD kidney cancer. There are many types of PTA. The most common are called radiofrequency, microwave and cryoablation. The type you get may depend on the experience of the person carrying out the procedure as well as the size and location of the tumour.

What did the researchers do?

This study looked at anyone with BHD who underwent PTA between 2007 and 2021 under the Reference Centre of the National Network for Rare Cancers in Adult PREDIR in France. In this timeframe, 6 people with BHD were identified. 4 people had previous surgery on the same kidney and one person had their other kidney completely removed. A total of 19 tumours were treated across 14 PTA sessions. Most of these tumours were treated using radiofrequency PTA. One was treated using microwave PTA and another tumour was treated using cryoablation.

All the tumours were treated successfully. This means that there was no evidence of the tumour remaining or spreading after treatment during the follow-up period (an average of 74 months). 5 of the people treated had chronic kidney disease. There was a slight reduction in kidney function after PTA in these people. However, none of the people treated developed kidney failure or required dialysis.

What did they learn?

In this study, PTA was found to be a successful way of treating kidney cancer in people with BHD. PTA has both benefits and limitations compared with surgery. PTA can be carried out without the need for general anaesthetic. General anaesthetic can increase the risk for having a collapsed lung in people with lung cysts due to BHD. It also appears that multiple rounds of PTA can be carried out successfully. However, it should be noted that surgery can be more challenging after ablation.

PTA could be particularly relevant for people in which surgery might not be suitable. This includes the elderly or people with reduced kidney function. However, the number of people in this study was very small. A larger study that could directly compare the effectiveness of PTA with surgery would be warranted.

Take part in research

As BHD is a rare condition, it is often difficult to get enough people to take part in a study to be able to draw conclusions. We launched the BHD Syndrome International Registry to capture as much information about BHD as possible. Sign up to the registry now to help us speed up and drive forward research.

Birt-Hogg-Dubé syndrome (BHD) is associated with an increased risk of kidney cancer. Currently, people with BHD should get their kidneys monitored regularly to check for tumours. If these tumours reach 3 cm, surgery is done to remove them. However, there may be some situations where surgery isn’t appropriate. Therefore, there is a need to develop new treatment strategies for kidney cancer in BHD. To do this, we need a good understanding of how kidney cancer develops in BHD. This includes knowing which type of kidney cell the cancer came from and how these cells differ in their gene expression patterns.

A study published earlier this year looked at different inherited kidney cancers at a single cell level. This means looking at the individual cells that make up the cancer. They did this by taking samples from kidney tumours that were being surgically removed. In this study, there was one chromophobe kidney cancer tumour and one hybrid oncocytic chromophobe tumour (HOCT) from people with BHD. They then split the tumour into individual cells and used a technique called RNA sequencing.  This technique tells us which genes are turned on or off in cells. Doing this at a single cell level (instead of the entire tumour) allows us to know what is happening in each cell. This is important because tumours are complex and made up of many different cell types. A “map” can be created from the RNA sequencing data, where each cell is placed based on which genes are turned on in that cell. The cell type can be identified based on which genes were found. Cells that have similar genes turned on will be close to each other on the map. On this map, the researchers found that cells from BHD kidney cancers were close to a type of kidney cell called collecting duct. This suggests that BHD kidney cancers may originate from this cell type.

Next, the researchers looked at which genes were turned on specifically in the different types of BHD kidney cancer. It is common to only know which type of kidney cancer you have after surgery to remove the tumour. However, it may be useful to know which type of kidney cancer you have before treatment as this may influence the treatment you get. For example, different types of kidney cancer grow at different rates and some are more likely to spread than others. The researchers found that different genes were turned on/off in chromophobe cancer vs HOCT. In the future, a test may be able to look for these genes to identify which type of cancer a person has. Of particular interest, the authors of the study also identified a gene called MET found at high levels in BHD kidney cancers compared with other kidney cancers. There are already MET inhibitors that are approved for treating cancer, including kidney cancer. Therefore, the use of these inhibitors should be investigated further in BHD kidney cancer.

Altogether, this study used the latest technologies to further understand inherited kidney cancers. We look forward to seeing more research to understand how kidney cancer develops and how it can be treated in the future.

Katty was diagnosed with Birt-Hogg-Dubé syndrome (BHD) in 2019 and was advised not to fly by her doctors. Having been a travel artist and looking forward to exploring the world with her sons, this news was very difficult.

In 2022, Katty wrote to the BHD Foundation in search of more information about BHD. Based on discussions with BHD experts and results from published research we explained that we do not advise against flying and it’s an individual’s choice. Current research suggests that if 1000 people with BHD flew on a plane, 1 or 2 of them would have a lung collapse. Pleurodesis may reduce this risk.

Although you can fly with BHD, you should not fly if you have a collapsed lung. This is because it will likely make it worse. If you have any symptoms of a collapsed lung you should see a doctor immediately.  

We spoke to Katty about her experiences being diagnosed with BHD and the challenges she faced when trying to find information about flying.

Watch the full interview below or read the transcript.

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Every few months we highlight some of the recent Birt-Hogg-Dubé syndrome (BHD) case reports. A case report is a detailed account of (normally) a single person’s diagnosis and treatment journey. Case reports are published in medical journals and are an opportunity for clinicians to learn about how different conditions may present.

In this blog we look at two cases of cancer in BHD patients. 

BHD is characterised by skin bumps (fibrofolliculomas), lung cysts, collapsed lungs and kidney tumours. The kidney tumours are normally slow-growing so with regular scans they can be monitored and removed if they reach 3cm. At the BHD Foundation, we often get asked if BHD is associated with any other cancer types. This is a difficult question as 1 in 2 people will get some type of cancer in their lifetime and most of these people do not have BHD.  Therefore, how do we determine if other cancers are caused by BHD or are unrelated?  

The case reports below describe two different types of cancer in people with BHD. A case study on its own cannot prove a link between BHD and a cancer. To find a link you need lots of data. This is where the BHD syndrome international registry (BIRT) comes in. BIRT is a patient-reported database where patients can upload information about their BHD. This data will feed into research and help answer vital questions. The reason case studies are still important is they can help researchers to identify areas of potential research.  

Cancer in the adrenal gland

The first case* described a 38-year-old man with a tumour on his left adrenal gland. The adrenal glands are two small glands that sit on top of the kidneys and produce hormones. Further investigations led to a formal diagnosis of a rare type of cancer called adrenal cortical carcinoma (ACC). In other words, cancer in the outer layer of the adrenal gland. He was treated with surgery and chemotherapy.

The next step for the clinicians was to find out why he developed this cancer. ACC is a rare cancer and is linked to genetic conditions including Li-Fraumeni syndrome. Therefore, they performed genetic testing. The test revealed a mutation in the gene folliculin (FLCN). Variants in this gene cause BHD. A diagnosis of BHD was further supported by the finding of skin bumps and lung cysts.

Once the diagnosis of BHD was confirmed, the doctors speculated on whether there could be a link between adrenal gland cancers and BHD. So far 5 cases of adrenal gland cancer have been reported in BHD patients including one other case of ACC.

Follicular Dendritic Cell Sarcoma

The next case discussed a 34-year-old man with low iron and blood in his stools. He had a camera test to check the inside of his bowels and they found a mass. He had surgery to remove the mass and was then diagnosed with a rare cancer called follicular dendritic cell sarcoma (FDCS). FDCS is a cancer that develops from specialised immune cells. It normally occurs in lymph nodes but can occur anywhere in the body including the digestive tract as seen in this case.

Next, the clinicians investigated the cause of his cancer. The patient had an extensive family history of cancer which suggested there may be a genetic component.  He was tested for several cancer-causing genes and had a positive FLCN mutation. Similar to the previous case, he was then found to have skin bumps to support a diagnosis of BHD.

This is the first case of FDCS to be reported in a BHD patient. It must be noted FDCS is very rare cancer with only 32 cases of FDCS in the digestive tract reported. The authors felt that it was unclear whether BHD was the cause of the FDCS or if it was just a coincidence that the patient had the mutation.  

Key messages

These case reports describe two rare cancers in people with BHD. However, as discussed above this does not mean that they are caused by BHD. As more data accumulates in the registry we can start to build a clearer picture of whether any other cancers are associated with BHD and if any other cancer screening is needed.

These cases also highlight the need for increased awareness of BHD. Both patients had skin bumps before their cancer diagnosis. However, neither of them had been investigated for BHD. However, it is promising to see FLCN included in genetic cancer screens. By being diagnosed with BHD, even if it had nothing to do with their symptoms, both patients will receive vital monitoring of their kidneys. This means if they do develop kidney cancer in the future it will be identified and treated as early as possible.

*Please note this paper is unfortunately not freely available. Please email contact@bhdsyndrome.org if you have any questions.

The BHD Foundation was delighted to host the BHD Community Symposium online on October 8th, 2022. If you couldn’t attend, you can read our research report and our advocacy report. We will be making the recording available to all registered attendees very soon.

We asked attendees to complete a short survey at the end of the symposium to provide their feedback. This feedback will help to inform future events. We had 19 responses, 7 from researchers and/or clinicians and 12 from people with BHD. We were thrilled that everyone found the symposium useful and that they learned something new. We asked people to vote for their top 3 sessions. The most popular sessions were

1. Research Talks – we heard from researchers around the world discuss their work on BHD
2. Meet the Experts – we had 3 ‘rooms’ featuring a Q&A with skin, lung and kidney BHD experts
3. ‘BHD and Me’ – a patient-led panel discussion where people with BHD shared their lived experiences

Importantly, everyone thought that the research talks were clear. As this event was designed to be accessible for all members of the BHD community, this was a priority for us. However, the proportion of people who strongly agreed with the statement ‘The research talks were clear’ did differ between researchers/ clinicians and people with BHD. Over half (4/7) researchers/ clinicians strongly agreed that the research talks were clear. A quarter (3/12) people with BHD strongly agreed that the research talks were clear. Everyone else that provided feedback agreed with the statement. At future community-focused symposiums we will strive to improve this statistic.

We also asked 3 open questions:

1. What did you like about the BHD symposium?
2. How could the symposium have been improved?
3. What would you like to see at next year’s symposium?

The responses to the first question have been used to create the word cloud you can see in the poster below and we have included select responses at the end of this blog. When asked how the symposium could be improved, the overwhelming response was that you wanted more! There were requests for more research and longer research talks, more patient testimonies and more opportunities for networking. Another common response was accessing the symposium due to time differences. As a charity that supports people with BHD around the world, we understand that time differences can be challenging. We had over 200 people from 22 different countries registered for this year’s symposium. To reach as many people as possible we recorded the event. We are making the recording available to everyone who registered very soon to watch at your convenience.

When asked what you would like to see at next year’s symposium, again the response was that you wanted more! The feedback we got requested more research, sessions on the treatment of BHD and more panel discussions. There was also a request to feature more work from underrepresented countries. This year, we were delighted to have researchers from 8 different countries present their work. Next year, we hope to welcome even more researchers.

Luckily, our symposium next year will be held over 2 days on October 13^th and 14^th 2023. It will be taking place in London, UK but there will also be an option to join online. Although research-focused, everyone is still invited to attend. We will be announcing further details about next year’s symposium soon. To receive updates, please sign up to our newsletter.

Selected quotes from the feedback survey in response to ‘What did you like about the BHD symposium?’:

“Breakout session enabled me to “meet” other scientists I know from reading but not to talk with. Before the end of the conference I was exchanging emails with one and may well ultimately do research with (just like after and in-person conference).”

“Perfect organisation, not easy to blend a public of patients, clinicians and researcher so well!”

“The chance to speak to experts – since my diagnosis 4 years ago I have tried to get answers to questions but have been given the wrong advice or no response. So thank you so much.”

“It is hopeful to see research is happening and get answers to some of my questions as well as more information for practitioners.”

“I enjoyed the atmosphere of being taken serious and cared for, because most doctors here in Germany have never heard of this disorder. Thank you very much for letting me attend the symposium.”

“I liked hearing about kidney cancer surgery and learning something new every time, especially when presenters can present in a way we can understand as non experts.”

“Seeing how other people from various parts of the world are together with a common goal.”

The 2022 BHD Community Symposium took place virtually on October 8^th. We were delighted to have over 200 people registered from across the world. The symposium was designed to connect people with shared experiences of Birt-Hogg-Dubé syndrome (BHD) and break down the barriers between patients, researchers and clinicians. It was an opportunity to learn from one another and drive forward BHD research.

Connecting with the Experts

Our Meet the Experts session facilitated discussion around the symptoms of BHD. We had three ‘rooms’ dedicated to lung, skin and kidney symptoms. Each room had at least two BHD experts. They provided a platform where patients, researchers and doctors could talk about treating and monitoring the symptoms of BHD.  

Kidney

In the kidney session, we were joined by Consultant Urological Surgeon Mr Rupesh Bhatt (UK) and research scientist Dr Laura Schmidt (USA). Much of the discussion focused on kidney screening in BHD, which currently has no formal guidelines. Both experts agreed that kidney screening should start in early adulthood. They advised against only having CT scans. This is because CT scans use radiation. Instead, the experts recommended MRI scans or ultrasound scans. The frequency of the scans depends on the type of scan being used and whether a person has a tumour. They also explained that as BHD tumours are usually slow growing any kidney tumour detected should be monitored and removed if it reaches 3cm.

Lung

In the lung session, we were joined by Professor Lisa Henske (USA), Professor Nishant Gupta (USA) and Professor Stefan Marciniak (UK). A range of topics were discussed covering many aspects of lung cysts and collapsed lungs. It was queried if lung cysts change over time in BHD. The experts thought there wasn’t much change in BHD, but that this data comes from small numbers of people over relatively short time frames. More work needs to be done to confidently answer this question.

One common question that comes up often is concerning certain activities such as flying or diving with BHD. The risk of having a collapsed lung in BHD is thought to be less than 1 per 100 flights. The risk is thought to be the same for diving, however there is less confidence in this number due to the low numbers reported. The presence of lung cysts is not a reason to avoid flying or diving. However, if you have the symptoms of a collapsed lung, you should not fly or dive.

Skin

We were joined by Professor Joyce Teng (USA) and Dr Ed Cowen (USA) for a fascinating session on the skin.

The session started with a discussion surrounding the incidence of skin bumps (fibrofolliculomas) in the BHD population. This can be age-related, and may explain a lot of the delayed diagnoses seen. However, fibrofolliculomas are thought to only occur in BHD. Therefore, if a biopsy is taken this should be a clear indication of BHD.

The impact of skin bumps on well-being was discussed, with various treatment options outlined. None of the current treatments provide a permanent solution as the skin bumps will return after treatment. However, people have had relative success with various treatments. Due to BHD being a rare condition, with little evidence on these treatments, there are no official guidelines as of yet regarding the most effective treatment.

Connecting with the community

As BHD is a rare condition it is unlikely that your family, friends or even your doctor have heard of it. We know that this can feel lonely. The BHD Foundation is trying to change this by raising awareness and bringing people together through events such as the symposium.

“…there was comfort in participating with a community of individuals facing similar issues as myself. It definitely provided a level of ‘assurance’ that we are not alone in this!” Feedback from BHD community symposium attendee.

In our final session, Bob, Julia and Barnaby shared their personal BHD stories. Although each had different symptoms, there were many similarities between them. This included the challenge of reaching a correct diagnosis. Two of the panel members were doctors and they described how they had never heard of BHD before their diagnosis.  They suggested that although doctors cannot know all 7000+ rare diseases, there should be a ‘collaborative effort between patient and physician to educate each other’.

“I liked that there were specialists in all aspects of BHD, especially that there were physicians who were also BHD patients like the rest of us.” – Feedback from BHD community symposium attendee

Another common theme of this session was how to discuss BHD with family members and things to consider around genetic testing. This included the effects on mental health, access to insurance and changes to lifestyle. As having BHD leads to a change in medical care (regular kidney scans) it was felt that informing family members is important. However, whether to get tested is an individual’s choice.

It was wonderful to see the community coming together with a common goal of raising awareness and advancing research into BHD. Through sharing stories and experiences, we can learn from one another and identify the areas of research that are needed to advance our understanding of BHD and ultimately find a cure.

We look forward to seeing you at next year’s research-focused conference. We are delighted to announce that it will be a hybrid event, so everyone can take part. It will be held both online and in London, UK.

Read part 1 of the BHD Community symposium report to find out about the current research into BHD.